holley billet metering block and emulsion jet question

Posted by: dartman366

holley billet metering block and emulsion jet question - 03/08/18 08:51 PM

long story short, taking my 8082 2 circuit dommy back apart from when it was switched over to E-85 in a futile attempt to run corn squeezin"s and back to 110 octane racing fuel,, I aquired a set of billet metering blocks but not sure what size emulsion jets I need and in how many ports, the blocks have 4 emulsion ports and one has a plug and the rest have none, per side,,I have no Idea where to start for size and placemen as I under stand the emultions set the fuel curve thru out the rpm curve and I definately don't want to be too lean, this is for a drag car only, 512 cubes 12.3 compression, 690 lift cam, 272 duration@50.
Posted by: mopar dave

Re: holley billet metering block and emulsion jet question - 03/08/18 09:39 PM

Yur gonna want to ask Dom, but i can tell you i use .028 emultions on my 1100 pump gas 511. I have 3 emultions with the center plugged. Youll need to pin gauge what you have.
Posted by: krautrock

Re: holley billet metering block and emulsion jet question - 03/08/18 10:39 PM

i think emulsion package sets the fuel curve early on when the boosters come in, after you get further into the fuel curve it's the high speed bleed that takes control.

get advice from dom. more emulsion isn't always better.
Posted by: mopar dave

Re: holley billet metering block and emulsion jet question - 03/09/18 12:27 AM

In my situation i started with .026 and after tuning every circuit the carb was still going fat on top, so per Doms recommendation i went to .028's and it leaned out that top end fat spot. Dom is the guy you need to see for the best carb advise.
Posted by: AndyF

Re: holley billet metering block and emulsion jet question - 03/09/18 12:30 AM

I don't think I've ever talked to anyone who understands emulsion jetting. Everyone just guesses at it. Nobody seems to know why Holley switched from 2 emulsion jets to 4 or 5. Maybe Braswell understands emulsion. At least he claims to but he never explains it so even he might not know.

Having said that, if you copy an old 850 DP you should be fine. Put an 028 in the top hole, blank in second, 028 in third and blank in the bottom. That should work well enough to get you going. You can play around with it if you want but I doubt you'll tell any difference. I've tried a bunch of different emulsion combinations over the years and never really noticed any difference.

If you really want to talk about emulsion jets then Tuner is probably the one guy on the internet who knows his stuff.
Posted by: sgcuda

Re: holley billet metering block and emulsion jet question - 03/09/18 06:49 AM

If the metering blocks were designed as E85 specific, you might need some other changes, too. There is a lot more to metering blocks than just emulsion. Check with Dom.
Posted by: Leigh

Re: holley billet metering block and emulsion jet question - 03/09/18 07:14 AM

Pretty sure he's got gas replacement metering blocks to change back.
Posted by: Mattax

Re: holley billet metering block and emulsion jet question - 03/09/18 07:48 AM

re: Tuner on emulsion
https://www.tapatalk.com/groups/racingfuelsystems/emulsion-tuning-t42.html
Posted by: mopar dave

Re: holley billet metering block and emulsion jet question - 03/09/18 09:03 AM

Very informative. Thanks for the linc. Also, you will need a wide band while tuning those emultions.
Posted by: BradH

Re: holley billet metering block and emulsion jet question - 03/09/18 11:06 AM

Originally Posted By dartman366
... I aquired a set of billet metering blocks... have 4 emulsion ports and one has a plug and the rest have none, per side...

Sounds like QFT/Proform 4-emulsion blocks (same thing except the anodized color). As an FYI, I've cut-n-pasted something about those blocks that I posted recently on another forum:

"I've had 2 sets of the QFT/Proform 4-emulsion billet blocks and their emulsion orifice sizing has been all over the place. The specs I found indicated the as-drilled e-holes are supposed to be .028", and they say to open up the pre-drilled hole to about .050" if you're going to convert to screw-in jets.

The first set ranged from .024" to .028", so I equalized them all to .028". The second set was just under .027" on one block and just over .029" on the other. For that set I simply opened the undersized holes to .029" and figured I'd drill 'em all bigger if I decide to change sizes in the future. The siphon breaks were different between the two blocks, too. The other thing to check are the sizes of the pre-drilled IFRs & PVCRs, which I've also found to vary quite a bit from what advertised specs I can find.

I still think that the QFT & Proform parts are drilled by blind monkeys given how poorly they're done and how inconsistent their sizes can be, too. "Quality Control"... what's that?"

Definitely give 'em the scope before just pluggin' holes and slapping them on.

Are you aware of any other mods that were done to the 8082 as part of the E85 conversion? IIRC, those mods often include changing the sizes of the booster passages to support the additional fuel required for an alcohol tune. That type of thing needs to be "rolled back", if so.
Posted by: Mattax

Re: holley billet metering block and emulsion jet question - 03/09/18 05:01 PM

Originally Posted By mopar dave
Very informative. Thanks for the linc. Also, you will need a wide band while tuning those emultions.


Your welcome. And I agree that logging with a wideband will show if the AFR is staying flat at WOT and the effects of changing air bleed or e-holes until it is.

Jmarkaudio's suggestion in that thread seems to be a good systematic way of approaching the e-hole sizing.
Posted by: dartman366

Re: holley billet metering block and emulsion jet question - 03/09/18 05:26 PM

Thanks guys this is a start, I intend on giving Dom a call but seen on facebook where he is/was down sick and didn't want to call him yet,,but I will, so I decided to post here and see what you guy's have to say about it,,,to my knowledge there is nothing left of anything E-85 I have already replaced the boosters and stakes and polished the throats of the main bores and took some roughness out of them, I have also pinned all the orfices and have numbers,,Idle feed restriction in main body is .098 or #40 drill,,high speed enrichment or PVCR's are .055 or #54 drill emulsions are all open except for a plug in the second one up from the bottom,, idle feed restriction in the block's are.033 or #66 drill,,booster stakes are .168 or # 18 drill, I now have pretty much everything to put this carb together and the only thing I need to do is run a tap in all the threaded holes to make sure it will screw together oh yeah I bought twenty blank jets so to drill them to the size needed,, keep it coming. up P.S. I do have a Innovate LM-2 and intend to get a second O2 sensor and use it heavily and have the program in my laptop so I can read it and save the charts for comparison.
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/09/18 11:45 PM

Originally Posted By AndyF
I don't think I've ever talked to anyone who understands emulsion jetting. Everyone just guesses at it. Nobody seems to know why Holley switched from 2 emulsion jets to 4 or 5. Maybe Braswell understands emulsion. At least he claims to but he never explains it so even he might not know.

Having said that, if you copy an old 850 DP you should be fine. Put an 028 in the top hole, blank in second, 028 in third and blank in the bottom. That should work well enough to get you going. You can play around with it if you want but I doubt you'll tell any difference. I've tried a bunch of different emulsion combinations over the years and never really noticed any difference.

If you really want to talk about emulsion jets then Tuner is probably the one guy on the internet who knows his stuff.


Nothing like insulting lots of smart guys that DO understand emulsion and other passages within a carb just because YOU don't..........Maybe we should bash your products mister wise guy and didn't you write a book that had a "Carb tuning" section..........Maybe EFI is best for you because you can push keys, make TONS of hp on your little optimist dyno but never post em.............THIS reaction from you really pisses me off I must say............... down tsk
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/09/18 11:47 PM

Call me anytime.............
Posted by: RustyM

Re: holley billet metering block and emulsion jet question - 03/10/18 03:51 AM

I honestly don’t think Andy intended his comment as a “ dis” to anyone.
I’ve read a good bit on the subject and a lot of it does seem quite subjective .
Different carb tuners do go about things differently as well.

Just my thoughts - from a guy who appreciates all the input here.
Posted by: 70RT Charger

Re: holley billet metering block and emulsion jet question - 03/10/18 04:29 AM

Andy’s comments sound pretty insulting to me and were geared toward Dom I thought.
Posted by: Bad340fish

Re: holley billet metering block and emulsion jet question - 03/10/18 07:44 AM

Originally Posted By 70RT Charger
Andy’s comments sound pretty insulting to me and were geared toward Dom I thought.


Oh come on, the last thing someone like Andy is going to do is want to stir up some Carb Drama. He didn't direct it at anyone he just stated his opinion. It is easy to find 10 different opinions on emulsion, which makes it easy to believe no one really understands it. I sure as heck don't lol.
Posted by: mopar dave

Re: holley billet metering block and emulsion jet question - 03/10/18 07:56 AM

Dom knows plenty about those emulsions and the rest of the circuits in a Holley carb for that matter. He gave me direction on a emulsion adjustment and the results were just as he said. Spent a bunch of time on the phone with him getting my 1100 tuned and in my opinion Dom knows his way around a Holley carb better than most.
Posted by: Mattax

Re: holley billet metering block and emulsion jet question - 03/10/18 08:53 AM

Originally Posted By 70RT Charger
Andy’s comments sound pretty insulting to me and were geared toward Dom I thought.


Unfortunately have to agree. Andy can say for himself what he intended, but it certainly came across just as Dom said. And just as Dom wrote, it slapped a bunch of guys that Dom and Andy know well. Anyone who pokes around at that link I posted above will figure out who Dom was refering to.

Originally Posted By Bad340fish
.... It is easy to find 10 different opinions on emulsion, which makes it easy to believe no one really understands it. I sure as heck don't lol.


Sure there are lots of opinions, but that doesn't mean no one really understands. It may mean there are a bunch of people willing to spout off as if they know something, whether or not they understand the principles. The people Dom refers to have spent the time and effort to learn the principles which are based in fluid dynamics, physics, and lots of engineering study. It's in NACA and similar research papers, along with the classic books on carburation and combustion engines by guys like Obert, Larew, Taylor. Many of these guys Dom refers to have been pretty helpful in sharing the sources and helping the rest of us understand this stuff enough to use practicaly.


Posted by: BradH

Re: holley billet metering block and emulsion jet question - 03/10/18 09:21 AM

"Tuner", whatever his name is, posted a link to a research paper from the 1960s that a group of Japanese engineers did that covers extensive computer modeling vs test results from an experimental carburetor on... emulsion. The correlation between them was very good.

I have a hard copy, but will see if I can find the link and post it.

Guys... it's science, not magic. I doesn't always do what we THINK it will, but it is reasonably predictable if you understand why. Part of why it's not as simple in the real world is the number of variables that influence it.
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/10/18 11:27 AM

Originally Posted By Mattax
Originally Posted By 70RT Charger
Andy’s comments sound pretty insulting to me and were geared toward Dom I thought.


Unfortunately have to agree. Andy can say for himself what he intended, but it certainly came across just as Dom said. And just as Dom wrote, it slapped a bunch of guys that Dom and Andy know well. Anyone who pokes around at that link I posted above will figure out who Dom was refering to.

Originally Posted By Bad340fish
.... It is easy to find 10 different opinions on emulsion, which makes it easy to believe no one really understands it. I sure as heck don't lol.


Sure there are lots of opinions, but that doesn't mean no one really understands. It may mean there are a bunch of people willing to spout off as if they know something, whether or not they understand the principles. The people Dom refers to have spent the time and effort to learn the principles which are based in fluid dynamics, physics, and lots of engineering study. It's in NACA and similar research papers, along with the classic books on carburation and combustion engines by guys like Obert, Larew, Taylor. Many of these guys Dom refers to have been pretty helpful in sharing the sources and helping the rest of us understand this stuff enough to use practicaly.


I didn't take it so personal myself but saying Braswell, Mark W and any top builders don't know how emulsion works is about as far out there as all of Arrogant Andy's 900+ hp motors..........You are an ex engineer Andy so maybe you should stick to that and it's VERY obvious why you didn't take the THUMPER EFI challenge cos you wouldn't have 1/2 the nut swingers you do now following your bs..........I don't claim to know it all but MOST of my results are good and I try and stay humble and learn as much as I can and ALWAYS answer the phone to help out when I can so there you go boy............What's really funny is that you NEVER defend yourself because you are that fing arrogant and I'm not politically wimpy correct so let this lay where it will......... beer
Posted by: dartman366

Re: holley billet metering block and emulsion jet question - 03/11/18 05:16 PM

the only other thing I found was the Transition slot jetting had been blowed out and I am fixing that problem according to thumpers instructions, just need to order some brass set screws from Fastenal here in town or from Mcmaster Carr then drill them accordingly.
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/12/18 01:28 AM

If there's enuff material there, drill n tap for 8-32 set screws and start at .055 and go up or down as needed but w/out an afr gauge it's a guessing game and LOTS of trial an error..........Good talking to you and if you do what we discussed you should be pretty close then salt to taste........ thumbs
Posted by: BradH

Re: holley billet metering block and emulsion jet question - 03/12/18 02:49 PM

Originally Posted By BradH
... a research paper from the 1960s that a group of Japanese engineers did that covers extensive computer modeling vs test results from an experimental carburetor on... emulsion. The correlation between them was very good.

I have a hard copy, but will see if I can find the link and post it.

No luck finding the link to the research paper mentioned above. I'll update this thread, if I do. scope
Posted by: dartman366

Re: holley billet metering block and emulsion jet question - 03/12/18 08:36 PM

Originally Posted By Thumperdart
If there's enuff material there, drill n tap for 8-32 set screws and start at .055 and go up or down as needed but w/out an afr gauge it's a guessing game and LOTS of trial an error..........Good talking to you and if you do what we discussed you should be pretty close then salt to taste........ thumbs
took the press in jets out the main body and checked and there is enough meat to make it work with 8-32"s, just ordered the brass set screws today from Fastenal, probably get on it this weekend and give you a call back when I get ready to screw this thing together just to make sure I have covered everything. I have a innovate lm-2 and going to get a couple of new SD cards and a second o2 sensor so I can read both banks, thanks for the info and insights, it was good to talk to you also, I feel a whole lot better about this pile of parts on my bench now up
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/12/18 09:26 PM

I love helping people out as others have done for me and you will get a good grasp and understanding of all of the circuits even the EMULSION that no one but Tuner seems to understand.......... drinking
Posted by: Harry's Taxi 2

Re: holley billet metering block and emulsion jet question - 03/13/18 08:07 AM

Originally Posted By Thumperdart
Originally Posted By Mattax
Originally Posted By 70RT Charger
Andy’s comments sound pretty insulting to me and were geared toward Dom I thought.


Unfortunately have to agree. Andy can say for himself what he intended, but it certainly came across just as Dom said. And just as Dom wrote, it slapped a bunch of guys that Dom and Andy know well. Anyone who pokes around at that link I posted above will figure out who Dom was refering to.

Originally Posted By Bad340fish
.... It is easy to find 10 different opinions on emulsion, which makes it easy to believe no one really understands it. I sure as heck don't lol.


Sure there are lots of opinions, but that doesn't mean no one really understands. It may mean there are a bunch of people willing to spout off as if they know something, whether or not they understand the principles. The people Dom refers to have spent the time and effort to learn the principles which are based in fluid dynamics, physics, and lots of engineering study. It's in NACA and similar research papers, along with the classic books on carburation and combustion engines by guys like Obert, Larew, Taylor. Many of these guys Dom refers to have been pretty helpful in sharing the sources and helping the rest of us understand this stuff enough to use practicaly.


I didn't take it so personal myself but saying Braswell, Mark W and any top builders don't know how emulsion works is about as far out there as all of Arrogant Andy's 900+ hp motors..........You are an ex engineer Andy so maybe you should stick to that and it's VERY obvious why you didn't take the THUMPER EFI challenge cos you wouldn't have 1/2 the nut swingers you do now following your bs..........I don't claim to know it all but MOST of my results are good and I try and stay humble and learn as much as I can and ALWAYS answer the phone to help out when I can so there you go boy............What's really funny is that you NEVER defend yourself because you are that fing arrogant and I'm not politically wimpy correct so let this lay where it will......... beer


I suspect andy f is being paid either directly or indirectly for the promotion of EFI, as of late he consistently points out his unproven assessment that EFI is superior to a properly tuned carb.
(it is not yet and likely never will with the exception of cold to warm street drivability)
Posted by: RustyM

Re: holley billet metering block and emulsion jet question - 03/13/18 08:51 AM

As to my comments on this thread, which only further inflamed things it seems:

1. I have been helped greatly by many here.
Over 30 years away from cars/ racing and catching up as been both exciting and difficult .
The folks here have been incredibly helpful.

2. It’s in my nature to to see the best in folks, help resolve conflicts etc. I certainly should have realized with a forum this size and been around this long, there would be a few issues/ conflicts of opinion etc.

3. I’m a guy that thrives on “ think tank” type differences in thinking that usually produce excellent problem solving - I did not realize this thread contained more than that.

4. I’m so far behind in so many areas- emulsion certainly being one- I should have kept my mouth shut .

5. Andy has been helpful to me as has Dwayne , Thumper, Cab, Cm and so many others .
Please forgive my attempt at “ benefit of doubt “ causing greater inflammation .

I appreciate you all- more than you can imagine.

This Moparts team has saved me countless funds, time, mistakes - your really invaluable to many folks - truly .

Just thought you should know that on the wider scales of things- this digital shop makes a real difference because of all of you- differences not withstanding.
Posted by: Mattax

Re: holley billet metering block and emulsion jet question - 03/13/18 12:22 PM

Originally Posted By RustyM
As to my comments on this thread, which only further inflamed things it seems:
...

Rusty, No apology needed.
I'm glad you posted what you did.
A. If you and bad340fish hadn't said anything, then you might still be thinking this area is a matter of unknown variables with lots of opinions. It was an opportunity to set the record straight. BradH summed it up so well:
Quote:
"Guys... it's science, not magic. It doesn't always do what we THINK it will, but it is reasonably predictable if you understand why. Part of why it's not as simple in the real world is the number of variables that influence it."
It takes experience and a bit of an art to stay within the stable range and reduce the number of trials, but it is all grounded known principles. Guys like Dom, BradH, Tuner, Mark W, Shrinker (RIP) and others have all been willing to share the parameters and approaches which have worked (or not) to make it easier for us.

B. There was no way for you and many others to know how insulting Andy's statement was. Sure, if you read the link and poked around RFS, MSV, YB and ST, it might have become apparent. But most guys here aren't doing that. AndyF has been helpful to me on occassion. I appreciate that. I left my response wide open for him to say it was inadvertent.

If you like a "think tank" atmosphere, I'll encourage you to spend some time checking out the RFS forum for carbs, FI, and ignition related discussions.
Posted by: RustyM

Re: holley billet metering block and emulsion jet question - 03/13/18 01:27 PM

Will check that out Mattax- thanks!
Do indeed enjoy the “ think tank” type work - good for the grey matter .

Talked to the Local carb tuner and- have a better grasp now as he stated similar to Brad.
The math is the math.
The problem he stated ( if I got it this time ) is that we are often dealing with less than precision instruments ( carbs) which carb tunes try to rectify and then all the variables of fuels/ air quality etc.

Thus some see this area as “ magic “ while those dealing with the science are dealing with math and- headaches- grin.

He also stated- Carbs are funny things because they go on engines and engines are funny thing because people build them- we don’t get cookie cutter constants and that’s why we get to make a living .

That’s pretty close- best I remember anyway .

He just had one for a 1600 hp , well built engine and carb just “ wouldn’t work “ after everyone tried all they could- sent it to him.

Couldn’t find a thing wrong ,,, until he noticed the scratch “ pattern “ on baseplate.
Checked it for flat- sure enough, wasn’t .
He dyed it and measured- someone had taken a sanding belt to it!
12 thou milled off later- great carb!

Magic?
Nope .

Math and attention to detail?
Yep.


Btw- am I The last guy on here to see “ Thumper carbs “ on Facebook ?

Sheesh - sweet .
Take me another few days to study that page - some really nice pieces there.
Posted by: Mattax

Re: holley billet metering block and emulsion jet question - 03/13/18 01:57 PM

beer

Along the lines of your guy's comment;one point Shrinker made is that a well designed e-bleed system allows more latitude for variations in engines than a solid fuel carb (he should know he made such carbs for his customers).

If you're up for another way of approaching carburetion
Originally Posted By "Shrinker"
.. think of an engine as a machine to raise the energy level of a fuel to as high as possible prior to initiating controlled combustion. That sentence really needs thinking about. If you approach an engine that way it opens a whole new way of thinking...
A little teaser from
"Emulsion" posted at MSV

It sounds very brainy, but just being aware of it I found is helpful.
Posted by: RustyM

Re: holley billet metering block and emulsion jet question - 03/13/18 02:10 PM

yep
Posted by: BradH

Re: holley billet metering block and emulsion jet question - 03/13/18 02:18 PM

To be honest, my carb tuning skills need to be stepped up quite a bit. At times it doesn't feel as if I'm much beyond "If it goes faster with bigger jets, it must be tuned right". What I thought I "knew" about setting up baseline tunes for my carbs last fall sure didn't prove itself well on the dyno, but it gave me a bunch of new questions and approaches to consider. Getting to use a wideband 02 on my car with my carbs should be a learning experience.

Also, I did locate the research paper I'd mentioned above here:

"Effects of Air-Bleed Systems on Carburettor Performance"
Yasuke ASANO, Toshitaka CHUMA, Heiichiro HAGA, Tadahiro MOCHIDA

Overview: https://www.jstage.jst.go.jp/article/jsme1958/11/46/11_46_691/_article

Download: https://www.jstage.jst.go.jp/article/jsme1958/11/46/11_46_691/_pdf/-char/en


It turns out there is also a "sequel", although I haven't found a copy that's been translated into English. Even though it's still in Japanese, I'm going to see if I can make any sense of the diagrams since they're presented in a similar manner to those in the original paper.

"Effects of Multihole Air-Bleed Systems on Carburettor Performance"
Yasuke ASANO, Ichiro ISOBE

Overview: https://www.jstage.jst.go.jp/article/kikai1938/37/297/37_297_1026/_article

Download: https://www.jstage.jst.go.jp/article/kikai1938/37/297/37_297_1026/_pdf/-char/en >> IN JAPANESE <<
Posted by: RustyM

Re: holley billet metering block and emulsion jet question - 03/13/18 05:29 PM

brad: What wide-band system are you going to use?
Posted by: dartman366

Re: holley billet metering block and emulsion jet question - 03/13/18 05:40 PM

Originally Posted By RustyM
As to my comments on this thread, which only further inflamed things it seems:

1. I have been helped greatly by many here.
Over 30 years away from cars/ racing and catching up as been both exciting and difficult .
The folks here have been incredibly helpful.

2. It’s in my nature to to see the best in folks, help resolve conflicts etc. I certainly should have realized with a forum this size and been around this long, there would be a few issues/ conflicts of opinion etc.

3. I’m a guy that thrives on “ think tank” type differences in thinking that usually produce excellent problem solving - I did not realize this thread contained more than that.

4. I’m so far behind in so many areas- emulsion certainly being one- I should have kept my mouth shut .

5. Andy has been helpful to me as has Dwayne , Thumper, Cab, Cm and so many others .
Please forgive my attempt at “ benefit of doubt “ causing greater inflammation .

I appreciate you all- more than you can imagine.

This Moparts team has saved me countless funds, time, mistakes - your really invaluable to many folks - truly .

Just thought you should know that on the wider scales of things- this digital shop makes a real difference because of all of you- differences not withstanding.


I can say I agree with everything you said here with the exception of your comment about being inflametory, some times things typed on a computer is misconstrued and /or misunderstood because tone of voice is missing and also facial or body language is not seen either, which make's it easier to understand how the person intended for the comment to be taken, is that what happened here? don't know, maybe, maybe not, but to me its over and in the past, I am glad it didn't kill the post like so many times before, so to me I see where you did NO wrong and maybe we all can learn some technical stuff. up
Posted by: pittsburghracer

Re: holley billet metering block and emulsion jet question - 03/13/18 05:54 PM

When you type something end it with lol or one of these up then you can always deny it. Lol.
Posted by: G-Money1320

Re: holley billet metering block and emulsion jet question - 03/13/18 07:17 PM

Bill ,you are definitely in good hands with Dom. as I am patiently waiting for my new carb to show up from him!! Lots of phone time and more knowledge than I ever knew existed about carbs!!
Posted by: dartman366

Re: holley billet metering block and emulsion jet question - 03/13/18 07:44 PM

Originally Posted By G-Money1320
Bill ,you are definitely in good hands with Dom. as I am patiently waiting for my new carb to show up from him!! Lots of phone time and more knowledge than I ever knew existed about carbs!!
I believe you are correct but I wish the phone connection was better and I didn't have to make him repeat so many times, don't know what was going on there. shruggy
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/13/18 09:40 PM

Originally Posted By G-Money1320
Bill ,you are definitely in good hands with Dom. as I am patiently waiting for my new carb to show up from him!! Lots of phone time and more knowledge than I ever knew existed about carbs!!


beer
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/13/18 09:45 PM

Originally Posted By RustyM
Will check that out Mattax- thanks!
Do indeed enjoy the “ think tank” type work - good for the grey matter .

Talked to the Local carb tuner and- have a better grasp now as he stated similar to Brad.
The math is the math.
The problem he stated ( if I got it this time ) is that we are often dealing with less than precision instruments ( carbs) which carb tunes try to rectify and then all the variables of fuels/ air quality etc.

Thus some see this area as “ magic “ while those dealing with the science are dealing with math and- headaches- grin.

He also stated- Carbs are funny things because they go on engines and engines are funny thing because people build them- we don’t get cookie cutter constants and that’s why we get to make a living .

That’s pretty close- best I remember anyway .

He just had one for a 1600 hp , well built engine and carb just “ wouldn’t work “ after everyone tried all they could- sent it to him.

Couldn’t find a thing wrong ,,, until he noticed the scratch “ pattern “ on baseplate.
Checked it for flat- sure enough, wasn’t .
He dyed it and measured- someone had taken a sanding belt to it!
12 thou milled off later- great carb!

Magic?
Nope .

Math and attention to detail?
Yep.


Btw- am I The last guy on here to see “ Thumper carbs “ on Facebook ?

Sheesh - sweet .
Take me another few days to study that page - some really nice pieces there.


That page is ok but the page I'm on most and chat through is Dominic Thumper but I appreciate the props and the ONLY reason I got a bit crazy is because of the insults by someone who has no clue. I don't and refuse to take jabs from anyone who doesn't know me or who doesn't know jack about their statements and MOST guys on here ROCK w/a few douche nuggets sprinkled in for good measure.............enjoy....... beer
Posted by: hemi-itis

Re: holley billet metering block and emulsion jet question - 03/13/18 10:09 PM

We need a "like" & "LOL" button!! shruggy
Posted by: Mattax

Re: holley billet metering block and emulsion jet question - 03/13/18 10:34 PM

There's lots of ways to prevent or correct a misunderstanding. Let's see what happens.
Posted by: max_maniac

Re: holley billet metering block and emulsion jet question - 03/13/18 10:36 PM

Originally Posted By dartman366
Originally Posted By G-Money1320
Bill ,you are definitely in good hands with Dom. as I am patiently waiting for my new carb to show up from him!! Lots of phone time and more knowledge than I ever knew existed about carbs!!
I believe you are correct but I wish the phone connection was better and I didn't have to make him repeat so many times, don't know what was going on there. shruggy




Bill if you would finally get rid of the can/line phone you may get a better connection --- haha haha panic
Posted by: Mark Whitener

Re: holley billet metering block and emulsion jet question - 03/13/18 11:53 PM

Well lets see if I can prove Andy wrong here.

You have to understand the reason for an emulsion system. Take your C&S Aerosol billet carbs, they do not us a booster, they use a discharge tube. There is no emulsion used, save for a very small main air bleed and one bleed above float level to act as a kill bleed. A tube senses airflow at a one to one ratio as the pressure difference or vacuum increases, so fuel flows in a direct proportion to the airflow thru the carb, so only a main jet is needed to set the correct amount of fuel. A booster however does not flow one to one, it flows in a straight line as pressure difference or vacuum increases, however the airflow curves towards a horizontal flatline.
As a result an air correction system, emulsion, is needed to allow the booster signal to follow airflow. And it is there mostly for air correction, emulsion or emulsified fuel is a result of the air correction, and should not be relied on to emulsify the fuel. This is where some carbs go off the deep end.

The second part of the air correction/emulsion passage on a standard Holley 4 barrel is that it holds fuel, so as air is pushed from the main air bleed down the well the fuel is pushed out of the emulsion bleeds, making it an added acceleration circuit. Remember this.

So what happens is as the signal becomes strong enough to start fuel flow it also tugs on the emulsion passage. Any bleed above fuel level will delay the start, and will depend on the total area of the bleed or bleeds and the size of the main air bleed. This is where bigger and smaller main air bleeds can delay or speed up a little the start. However once the fuel flow starts the large bleed can actually fatten it quicker, allowing the fuel in the emulsion well to be pulled faster into the mainwell. This can make it excessively rich early with a larger bleed, and combined with a lot of emulsion goes off the deep end. Then as RPM's and demand climbed it shoots the other way, goes lean. I see this when more than 3 bleeds and over .028" emulsions, and over .030 main air bleeds. What also happens is the air goes thru in big slugs making the fuel curve choppy, fuel is not mixed well with the air coming into the mainwell. It leaves the booster in spurts rather than an even mix. Once the fuel is depleted to the bottom open emulsion hole then it just feeds air, until the throttle is closed and the mains stop, and the emulsion well is allowed to fill again.

So what do you want to accomplish? It depends on the application, fuel type, engine demands... What I find is when you use a booster that atomizes fuel well to distribute fuel evenly you don't need any more air than what is needed for correction. For most gas carbs on the street a kill bleed and two .026-.028 holes spaced to go about half way down the well is plenty. I like smaller bleed for racing, and usually space three smaller bleeds. And if I can control the kill bleed size even better. With alcohols and oxygenated fuels, or big engines with two carbs you can place the bottom bleed all the way down, use all the fuel emulsion well. I set most race carbs up this way, but with a small bleed usually at .021 or smaller. I have a blow thru I reworking that will likely get a .021 at the top for a kill, .024 all the way at the bottom. And a last piece of this puzzle to remember is that at WOT the idle circuit that usually pulls from the bottom of the mainwell can now become a bleed into the main circuit, adding more air in....

Now with E85 you have a significantly different fuel in the mix. Too much air makes it stupid rich early, lean at the top. I've seen it chased on a dyno... once emulsion was set small it cleared things up. For E85 go real small, I've got an RS Demon that has .014 in the top, .016 third and .018 forth with the second and fifth plugged. For the Dominator get the top small, .014-.016, and .020-.021's in the third and fourth or third and fifth on 5 hole blocks.
Posted by: MR_P_BODY

Re: holley billet metering block and emulsion jet question - 03/13/18 11:56 PM

I meet a few of the Holley engineers in meetings
when I worked in the carb lab(wish I worked in
that area longer) but even they would argue in
some of those meetings.. I dont know what all
the argument is about but Andy stated his opinion..
I have have gotten good info from both guys and
thanks to both
EDIT
also guys.. remember.. cars are nothing but MATH
and its ALL math.. we dont just think up this stuff
wave
Posted by: RustyM

Re: holley billet metering block and emulsion jet question - 03/14/18 12:32 AM

After being out of this for 30 years , everyday is an adventure in learning .

Fwiw: In other fields I have spent enormous amounts of time on forums, in study groups/ social media groups.
Most of these have a limited useful lifespan and then start disintegrating before generally coming to death .
It seems Moparts has been around a good while - much longer than most formats of this type .
Personalities here “ self manage “ much better than most, including upper end academic groups.
I might also comment on the grace / help shown to new people - extreamly friendly and helpful.

In my opinion - this is a rare place/ combination today and it is that way because of the quality of the people here.
No- I’m not blowing wind up your dresses - just seen a lot - it’s an honest assessment .

I haven’t physically met anyone yet but have talked by phone, e-mailed, messaged and done some financial/ goods transactions - all of which have been as they should be.
I know I can ask questions and get not only help, but options to consider.

I appreciate this place and the people that make it what it is.

One thing that’s both good and rather sad:
I can get better information/ data here than I can from The company’s we all purchase from.
Example : One can get much better data on Trick flow heads here than one can from Trick flow.
Another: One can get much better information/ data here than one can from Holley.
I won’t mention Indy much.

Thought the other day- need sticker: Designed by Moparts
Posted by: cudadon

Re: holley billet metering block and emulsion jet question - 03/14/18 01:46 PM

Thanks Mark!

Don
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/14/18 02:00 PM

Originally Posted By cudadon
Thanks Mark!

Don


Mark W is a wealth of info for sure and has opened my eyes up to the many tuning scenarios involved in these carby thingies........... thumbs
Posted by: jbc426

Re: holley billet metering block and emulsion jet question - 03/14/18 06:23 PM

I was getting ready to increase the size of the fuel restrictor in my metering Promax billet metering block based on a lean wideband reading I was getting at idle. This is on the old Direct Connection 2300 series "racing" carbs with the mechanical outboards that have no idle circuits and blocked power valve holes in the metering blocks. I love these carbs and have been running them for years.

I was thinking that I had enough of an understanding of emulsion circuits and metering blocks to do what I was about to do. Heck, I was able to adjust the main jets using a wide band, so I thought I would just increase the main restiction jet 3 sizes from .031" to .034" and recheck the A/F ratio. I figured it would be richer at idle afterwards. After all, I had been getting readings of 22 & 24 to 1 before the gauge zero out due to leaness at idle. More fuel should work like increasing a main jet at cruise and wide open throttle I thought. It might have.

I knew I had too much of the idle transfer slot uncovered from watching Youtube videos on Holleys. I tried opening the outboard carbs throttle blades very slightly to simulate drilling holes in the center carb throttle plates. As I closed the center carb's throttle blades using the idle screw, a surprising thing began to happen. After a few minutes, I had the center carb closed up significantly, and the outboard carbs open about a half a turn of their idle screw from fully shut.

To my surprise, the A/F ratio was now in the mid to low 15's at 900 rpm. The idle is much more stable and the response off idle is as good or better than it ever has been.

I expected that bypassing more air through the outboards would have leaned out the A/F ratio even more than it had been. It actually richened it up and the car is running better than ever now. Can anyone clarify the physics behind that?

On a side note, I have C&S building me a set of aerosol 500 cfm mechanical carbs using the body of a spare outboard I found on Ebay. I'm looking forward to a back to back chassis dyno test to see if they build more power.
Posted by: ccdave

Re: holley billet metering block and emulsion jet question - 03/14/18 07:03 PM

All I know is not to use those springs with that rocker.
Posted by: dartman366

Re: holley billet metering block and emulsion jet question - 03/14/18 08:02 PM

Originally Posted By max_maniac
Originally Posted By dartman366
Originally Posted By G-Money1320
Bill ,you are definitely in good hands with Dom. as I am patiently waiting for my new carb to show up from him!! Lots of phone time and more knowledge than I ever knew existed about carbs!!
I believe you are correct but I wish the phone connection was better and I didn't have to make him repeat so many times, don't know what was going on there. shruggy




Bill if you would finally get rid of the can/line phone you may get a better connection --- haha haha panic
time to up grade to a better string, but it still beats smoke signals. tonguue
Posted by: Mattax

Re: holley billet metering block and emulsion jet question - 03/14/18 08:20 PM

Quote:
I expected that bypassing more air through the outboards would have leaned out the A/F ratio even more than it had been. It actually richened it up and the car is running better than ever now. Can anyone clarify the physics behind that?
I'll give it a shot.

Originally Posted By jbc426
.... After a few minutes, I had the center carb closed up significantly, and the outboard carbs open about a half a turn of their idle screw from fully shut.

It seems like you balanced it. The engine consumes about the same amount of air - at least by volume. The total restriction to air flow is similar or little more than it was before. Enough so that the vacuum at the idle discharge areas is noticible higher than before.
This increase in pressure difference is moving more fuel through the idle circuits. This more than offset any drop in the air mass flow density.

Even at the lower throttle position, it seems likely in this case that the idle jets are still the main restriction on fuel at idle.

I'm curious, are the idle jets on this carb located below the fuel level?
Posted by: sgcuda

Re: holley billet metering block and emulsion jet question - 03/14/18 08:58 PM

Wow! Thanks, Mark. That is a very quick, fact filled explanation of the carb circuits. Very inspiring.
Posted by: jbc426

Re: holley billet metering block and emulsion jet question - 03/14/18 11:37 PM

Yes, I believe they are, but I'll have to double check.

Thanks for the insight.
Posted by: Mattax

Re: holley billet metering block and emulsion jet question - 03/15/18 09:02 AM

Originally Posted By jbc426
Yes, I believe they are, but I'll have to double check.

I was thinking about this. If the fluid was exactly the same we could compare areas of the discharge restrictions with the feed restriction. But that's not the case, even with the high position, additional air and pressure comes in at the top of the transfer slot.

Low position should be more consistant, so not encouraging a change to high.* Just curious as I was thinking about this.
*Summary and background of why low position is almost always better for us is posted here: Idle Jet Position
Posted by: jbc426

Re: holley billet metering block and emulsion jet question - 03/15/18 11:34 AM

Thanks, that is good stuff. I just found that site as a result of this post.
Posted by: dartman366

Re: holley billet metering block and emulsion jet question - 03/17/18 08:23 PM

well It's all together and ready to put on the motor and try it,,,if it's warm enough to open the doors of the garage, this was a little more involved than I expected, I just don't know how Thumper gets them done as quick as he does, and if it weren't for him I would still be scratchin' my head trying to figure it out. luck
Posted by: mopar dave

Re: holley billet metering block and emulsion jet question - 03/18/18 08:55 AM

Those Dominators are very complex. You change one thing and it also changes something else. Constantly chasing your tail trying to nail down the street tune. Glad i have Doms number.
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/18/18 12:33 PM

It's taken me years, many spark plugs, oil, fuel and wear n tear to finally get a grasp on this carby stuff and still learning every day but it's FINALLY paying off and I'm glad I could help you guys out........... beer
Posted by: dartman366

Re: holley billet metering block and emulsion jet question - 03/18/18 05:15 PM

Well,, it's on the car and running,,,and quite well I might add, once I got the float level set which was a little high and started to work with the curb idle screw's it came around quite nicely and sounds a lot crisper, idle tip in is smooth and there is no more blubbering like the other one(which I think I found the problem there) just smooth as silk up to the point the boosters took over, the other one sounded like it was loaded up a little and then would clean up so that is a big plus,, got it up to running temp for a while then shut it off,, let it sit for about 10 minutes and reached in and hit the start button and it was running and never touched the pedal,,,now for the tracks to open and start to dial this thing in. up and also a big thank you to Dom for bailing me out with good straight forward no BS answers and tech advise. up up
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/18/18 08:29 PM

Originally Posted By dartman366
Well,, it's on the car and running,,,and quite well I might add, once I got the float level set which was a little high and started to work with the curb idle screw's it came around quite nicely and sounds a lot crisper, idle tip in is smooth and there is no more blubbering like the other one(which I think I found the problem there) just smooth as silk up to the point the boosters took over, the other one sounded like it was loaded up a little and then would clean up so that is a big plus,, got it up to running temp for a while then shut it off,, let it sit for about 10 minutes and reached in and hit the start button and it was running and never touched the pedal,,,now for the tracks to open and start to dial this thing in. up and also a big thank you to Dom for bailing me out with good straight forward no BS answers and tech advise. up up



This is what I like to hear and now the tuning will begin but kudos to you for tackling what some consider too hard or impossible to do and I get it.......... beer
Posted by: G-Money1320

Re: holley billet metering block and emulsion jet question - 03/18/18 09:54 PM

Glad to hear Dom got you pointed in the right direction!! up Heres my new Dom built carb waiting on an install and test. I'm still not sure if I need to put it in the China cabinet or on the car!! grin
Posted by: BradH

Re: holley billet metering block and emulsion jet question - 03/20/18 07:36 AM

What size venturi & throttle? Looks like a Holley aluminum replacement main body wrapped in TC's preferred hardware.
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/20/18 12:15 PM

I THINK this one is the 1.610 bore and 1 3/4 blades but shipped so many lately I forgot........... punkrocka
Posted by: dartman366

Re: holley billet metering block and emulsion jet question - 03/20/18 08:48 PM

Originally Posted By Thumperdart
Originally Posted By dartman366
Well,, it's on the car and running,,,and quite well I might add, once I got the float level set which was a little high and started to work with the curb idle screw's it came around quite nicely and sounds a lot crisper, idle tip in is smooth and there is no more blubbering like the other one(which I think I found the problem there) just smooth as silk up to the point the boosters took over, the other one sounded like it was loaded up a little and then would clean up so that is a big plus,, got it up to running temp for a while then shut it off,, let it sit for about 10 minutes and reached in and hit the start button and it was running and never touched the pedal,,,now for the tracks to open and start to dial this thing in. up and also a big thank you to Dom for bailing me out with good straight forward no BS answers and tech advise. up up



This is what I like to hear and now the tuning will begin but kudos to you for tackling what some consider too hard or impossible to do and I get it.......... beer
Well it took me two and a half solid days to do it and several times I had to walk away from it for a while,,, but I guess persistance paid off, or maybe it's just stubborness.LOL whistling
Posted by: Thumperdart

Re: holley billet metering block and emulsion jet question - 03/21/18 02:41 PM

I do that DAILY..............LOL
Posted by: G-Money1320

Re: holley billet metering block and emulsion jet question - 03/21/18 09:05 PM

Yes you are correct Brad. I just have a small 416 though. smile A lot of phone time and I believe Dom has me where I need to be!
Posted by: jbc426

Re: holley billet metering block and emulsion jet question - 04/05/18 04:07 AM

Finally had the plate off, and the jets are above the fuel. Can I just drill and tap them into the lower hole? Or should I get a different metering block from someone who knows how to set one up?
Posted by: sgcuda

Re: holley billet metering block and emulsion jet question - 04/05/18 06:47 AM

You can drill and tap them. By hand, not with a power drill. Get in touch with Thumper for details.
Posted by: Mattax

Re: holley billet metering block and emulsion jet question - 04/05/18 09:16 AM

Use the ones you have.
See "Relocating the Holley Idle Jet"
RFS - Holley - Tips & Info Stickies