Moparts

Anyone Use Extrude Hone for Exhaust Manifolds?

Posted By: YO7_A66

Anyone Use Extrude Hone for Exhaust Manifolds? - 09/24/08 03:15 PM

I read a post that used the company name Extrude Hone out of Irwin Pa. I checked out their web sight and they show some pricing for doing V8 exhaust manifolds for $675.
http://www.gethoned.com/parts.php?get_price=yourparts&show=automotive

Has anyone tried this? If so, do they give a flow rating? Does anyone have any real-world experience that they can share? I hear that they are only worth minimal, but I am looking for actual numbers if anyone can help.
I have read other posts about this process, but I am looking to see if anyone has any dyno or time slip results to compare.

Thanks
Posted By: B G Racing

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/24/08 03:37 PM

Quote:

I read a post that used the company name Extrude Hone out of Irwin Pa. I checked out their web sight and they show some pricing for doing V8 exhaust manifolds for $675.
http://www.gethoned.com/parts.php?get_price=yourparts&show=automotive

Has anyone tried this? If so, do they give a flow rating? Does anyone have any real-world experience that they can share? I hear that they are only worth minimal, but I am looking for actual numbers if anyone can help.
I have read other posts about this process, but I am looking to see if anyone has any dyno or time slip results to compare.

Thanks


Waste of money
Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/24/08 03:37 PM

yes it has been done , what manifold do you want to have done , every design will react differently
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/24/08 03:48 PM

What it's "worth" will vary with every individuals opinion. Does it make a difference? Yes, the degree will vary with the deign as JohnRR suggests, as well as with your other parts in the combo, the benifits will vary depending on where the bottlenecks are in your combo. I have not done flow tests but have had a set of 340 manifolds done, as compared to stck they are not noticabley larger (hogged out, etc.) but they are extremely smooth and clean inside which I'm sure affects the flow in a positive mannor. My guess is 5-10HP gain overall, not much but when every bit counts a gain is a gain.

Attached picture 4707173-CenterPortBeforeExtrudeHone.jpg
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/24/08 03:49 PM

After, same port

Attached picture 4707174-CenterPortAfterExtrudeHone.jpg
Posted By: YO7_A66

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/24/08 03:57 PM

Thank you all for the quick replies.

I was reviewing the process for my 70 340 HP exhaust manifolds. I am currently trying to decide on a Winter project, and I am considering the Dougs or TTI headers. But when I read this thread, it got me curious when the price was lower than the TTi's. I will assume that the extrude hone will not give the performance of the Dougs/TTi's, but that got me curious to see if anyone has done any testing of their own on this process to see that the actual gains may be.

Thanks for the pictures Scott!!

I have emailed them to see if they have done any of their own flow/hp/tq tests but I have yet to hear back from them.

Thanks again.
Posted By: Ludington1

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/24/08 04:12 PM

There's a post in the race forum here on Moparts about F.A.S.T. intake/exhaust manifolds and there is some real-world feedback.

Darren
Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/24/08 05:21 PM

Quote:

Thank you all for the quick replies.

I was reviewing the process for my 70 340 HP exhaust manifolds. I am currently trying to decide on a Winter project, and I am considering the Dougs or TTI headers. But when I read this thread, it got me curious when the price was lower than the TTi's. I will assume that the extrude hone will not give the performance of the Dougs/TTi's, but that got me curious to see if anyone has done any testing of their own on this process to see that the actual gains may be.

Thanks for the pictures Scott!!

I have emailed them to see if they have done any of their own flow/hp/tq tests but I have yet to hear back from them.

Thanks again.




It's not going to give you the gains a set of full length headers do .
Posted By: YO7_A66

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/29/08 01:21 PM

I want to thank everyone for their replies.
I just received an email from Extrude Hone and this is what they said for performace gains on exhaust manifolds:
""Rick says that after processing the average airflow increase is 15% with an approximate 15 to 20 horsepower increase. The cost to Extrude Hone process your exhaust manifolds is $675.00 (per pair) plus shipping. The turn around time will be approximately two weeks""

I just wanted to pass on the information.
Posted By: 451Mopar

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/29/08 02:17 PM

A few years ago Mopar Muscle magazine had a coronet convertible project car with a 440 (If I remember correctly?)
Anyhow, they did a comparison with stock vs. extrude honed manifolds and it only resulted in a small performance gain. They then went to headers and got a pretty good performance gain. Sorry, I don't recall the exact numbers.
I would only do the extrude hone route if you have to use the stock manifolds.
Posted By: AdamR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 12:06 AM

Quote:

There's a post in the race forum here on Moparts about F.A.S.T. intake/exhaust manifolds and there is some real-world feedback.

Darren




I cant find that thread. Do you have a link to it ?
Posted By: Ludington1

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 12:11 AM

Try this link... or do a search in the Race forum for "F.A.S.T." and it will come up.

Darren
Posted By: AdamR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 01:27 AM

Thanks, I tried the search first with no luck.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 01:41 AM

Quote:

want to thank everyone for their replies.
I just received an email from Extrude Hone and this is what they said for performace gains on exhaust manifolds:
""Rick says that after processing the average airflow increase is 15% with an approximate 15 to 20 horsepower increase. The cost to Extrude Hone process your exhaust manifolds is $675.00 (per pair) plus shipping. The turn around time will be approximately two weeks""

I just wanted to pass on the information.





For the record, "Rick" is the guy who helped me get my 340 manifolds done, after seeing the before and after results first hand I find his WAG of 15% - 15-20HP gains pretty optimistic, possible? sure, probable? Not IMO. But I do think you could see roughly half that amount of gain in many cases. They are nice and smooth inside which will help flow, but the volume has changed VERY little, not much material has been removed and I asked for the "Max" amount be removed. I'd dare to say that simply ceramic coating the insides could result in similar gains in flow. For the record I would go to Extrude Hone again if looking for every last bit of HP, I'm happy with the work, not so much with the price, but went in with a conservative hopeful outcome so regardless of how minimal the gain, I'm happy so far. Dyno run is next week, I'm going to try and have some stockers dyno'd during the same run.
Posted By: Anonymous

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 01:58 AM

scott
did you do exhaust only
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 02:00 AM

Yes Tom, just the exhaust. The intake has some simple mods in the carb opening, otherwise it's stock. I believe adding to the plenum volume might be a benifit so EH'n it might have been a good way to go but I chose not to.
Posted By: Anonymous

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 02:06 AM

i,d be curious about doing intake,heads and exhaust as a matched set to see what the results might be
Posted By: SCATPK

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 02:07 AM

I have a real world comparison between extrude honed stock manifolds and a set of TTI headers on my old 70 340 swinger.
The engine was the original 340 that was bored .030 over with a somewhat hot hyd cam from Hughes engines and an Edelbrock RPM intake and Holley 3310 carb, heads had Hughes stage 1 porting done to them. Had the original 727 trans with shift kit and 2800rpm stall converter and 355 gears. I had the stock manifolds connected to the TTI system from the headpipes back and the car ran a best of 13.46@101mph. I then installed a set of TTI stepped headers and with no other changes ran a 12.76@106 on its first run down the track. So is the extrude hone worth it, not in my opinion.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 02:20 AM

SKATPAK,

All due respect, nobody is arguing that headers will out perform factory manifolds, of course they will, especially a warmed over engine. The question is, how much gain will Extrude Honed factory castings offer over untouched castings, and is (whatever that gain is) worth it?

Tomr,

My heads were already ported and done so no reason to EH them. Having all 3 done should result in a gain but I doubt it would match what customer ported heads would offer. I guess you could have custom ported heads EH'd as well.
Posted By: cogen80

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 02:22 AM

a while back i was talking with one of those F.A.S.T guys and he said he had his 340 manifolds done and it did nothing at all for him. even if it did help it better be a big difference for the price they get for that.
Posted By: Neil

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 02:33 AM

Too bad that some manifold designs make it almost impossible to get a porting bit up inside them because getting the opening bigger is what counts. My brother was able to really open up a set of buick 455 manifolds since they were more of a swept back design that exit facing the back of the engine. All he had to do was buy a couple really long porting bits to reach way up inside.
Posted By: SCATPK

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 02:40 AM

Quote:

SKATPAK,

All due respect, nobody is arguing that headers will out perform factory manifolds, of course they will, especially a warmed over engine. The question is, how much gain will Extrude Honed factory castings offer over untouched castings, and is (whatever that gain is) worth it?

Scott, it seemed that the original poster was considering going with headers and I just posted an actual comparison between the 2 different setups. No doubt that headers make a big difference in a warmed over engine! But in my opinion the extrude process is not worth the money for the small gain if any.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 03:01 AM

It's all good Herb. One thing's for sure, having driven allot of street/strip cars I am a big fan of stock manifolds, good all around performance, quiet, and mostly trouble free. Headers can be a PIA on the street but for drag racing they are king for sure.
Posted By: YO7_A66

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 04:01 PM

I just reviewed the article in Mopar Muscle when they dynoed the 7 different exhaust manifold/header combos and I am still surprised that the TTI's were only +16 ft/lbs and + 12 hp over the 70 HP units on the mild small block. I know that the numbers will go up as a motor gets more modified, but I am still trying to justify the price of the TTi's (apx $740) and the Doug's (apx $550) and the Extrude Hone (apx $675 + shipping) for only 16ft/lbs and 12 hp maximum gains.

I just want to thank everyone again for their replies and their experiences on this subject.

Attached File
4719882-340hpTTi.pdf  (301 downloads)
Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 04:17 PM

Quote:

I just reviewed the article in Mopar Muscle when they dynoed the 7 different exhaust manifold/header combos and I am still surprised that the TTI's were only +16 ft/lbs and + 12 hp over the 70 HP units on the mild small block. I know that the numbers will go up as a motor gets more modified, but I am still trying to justify the price of the TTi's (apx $740) and the Doug's (apx $550) and the Extrude Hone (apx $675 + shipping) for only 16ft/lbs and 12 hp maximum gains.

I just want to thank everyone again for their replies and their experiences on this subject.




Well if you BELIEVE what Extrude told you you'll see the same increase from their process as the TTi's ...

Posted By: dannysbee

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 04:20 PM

Your High Performance Mopar engines were blessed with a nice set of free flowing manifolds from the factory. For 99% of the street strip cars they will be more than adequite just the way Mopar made them. If it were me and looking for a little more performance I would concentrate down stream from the manifolds with a nice 2 1/2" mandrel bent exhaust with a x pipe and large free flowing mufflers.


I looked at you engine specs and looks like you have a nice combo. I also noticed you didn't mention any head work. If your heads are basically stock a good port and valve job from a reputable shop would probably give some good bang for the buck.
Posted By: YO7_A66

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 04:34 PM

Danny,
I an currently running 2-1/4" pipes with an H pipe, and two 440/Hemi style mufflers.
John,
I do not believe the Extrude Hone information and I was just passing on information to the board.

Thank you for the replies.
Posted By: dannysbee

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 04:57 PM

The X is better than the H, along with the 2 1/2" pipe. Both would help. The mufflers can be decieving. Big body with big inlets and outlets somtimes does not = big flow. I would look at the mufflers that ths F.A.S.T. guys are using as they are in 10's and 11's at the strip with a 2 1/2" exhaust. I looked at your engine specs and I believe some head work as in a nice port and valve job would be where I would put my money after the exhaust. Hope you find some of this useful.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 05:07 PM

Folks I will post a real world comparison next week. I have a set of untouched factory 71 A-body 340 manifolds as well as an identical set that have been Extrude Honed, both will be tested on the same engine with no changes and the same pair of exhaust pipe extensions. Keep in mind that any gains (or lack of) may vary with ANY engine combo, it's all about where the engines "bottlenecks" are, if it's the exhaust manifolds (which is what I expect mine will be) you might see a bigger gain with EH manifolds, in my case will will soon see.
Posted By: YO7_A66

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 05:29 PM

Dan,
I have already had the heads pocket ported along with the 3 angle valve job. Hopefully one of the FAST guys will chime in on some small block muffler choices. Thank you again.
Scott,
PLEASE check back in with us with your results and thank you for your efforts!
Posted By: B G Racing

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 07:18 PM

I was just going to leave my not worth the money comment stand for it's self.But after hearing the claims of increase %s I must comment further.Years ago we had a local racer peddeling the extrudeahone process.Butch Palm was the racer that I recall,anyway we got caught up in the action and had a set of manifolds(intake and exhaust)done for a 440 it was very pricey for back then.The car was a dialed in 440-6 cuda that ran low 12s consistantly.After the process the car lossed a tenth.We struggled with jetting and anything else we thought was effected with no results.We replaced everything back to stock(manifolds)and regained our loss tenth.Was it worth the time and money?Heck no!
Posted By: dannysbee

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 09/30/08 07:29 PM

Scott it sure would be neat to set that up with a X pipe and some high flow mufflers also. Just for a comparison between open pipes and real in car performance.
Posted By: AdamR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 11:08 AM

Quote:

Folks I will post a real world comparison next week. I have a set of untouched factory 71 A-body 340 manifolds as well as an identical set that have been Extrude Honed, both will be tested on the same engine with no changes and the same pair of exhaust pipe extensions. Keep in mind that any gains (or lack of) may vary with ANY engine combo, it's all about where the engines "bottlenecks" are, if it's the exhaust manifolds (which is what I expect mine will be) you might see a bigger gain with EH manifolds, in my case will will soon see.




Scott, anyway you can test a 68-71 passenger side manifold Vs your 71 passenger unit ?
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 03:40 PM

The dyno guy doesn't have an exhaust system other than the cobbled up pipes I provided (X-pipe vs H-pipe, etc) so there's no way I can do that comparo. All they had were headers for my engine.

Concerning the 70 style manifold, I don't have an EH'd pass side 70 manifold but I do have a stock one. The problem is that they are going to charge me for extra time in changing out parts and I already went out of pocket to do the EH vs non EH test that I did primarily to get you guys a real world test/answer. If anyone wants to pitch in $150.00 I will send over my 70 pass manifold off and have them compare those vs stock 71's as well.

This is the stock set I just gave them.

Attached picture 4722461-71StockExhaustManifolds.jpg
Posted By: CJK440

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 03:52 PM

I think thats the same pass side manifold my 72 has and I'm going to guess the only difference between the 71 and 72 drivers casting is the addition of that large rib on top. The rest looks the same.

People have told me 71's have a better set of manifolds than a 72 and I don't see why.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 03:54 PM

I agree, I have examples of both, PS 71 vs 72 I can see zero difference, also no difference betwen DS 71's and 72's in regards to internal shape.
Posted By: dannysbee

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 04:20 PM

The 71 manifolds look better but have no performance advantage. My buddy changed the 72 ps manifold to a 68-70 PS manifold and saw no measurable improvement. This was in a stock cubic inch 12 second car.
Posted By: UCUDANT

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 05:46 PM

Quote:

I agree, I have examples of both, PS 71 vs 72 I can see zero difference, also no difference betwen DS 71's and 72's in regards to internal shape.




Compare the shape of the drivers side upper/outer corner. The 72 is definately different externally, have you CC'd them for an internal comparison?
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 05:53 PM

No Bob, haven'tt CC'd them just a visual inspection.
Posted By: dOoC

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 06:02 PM

Almost 7 hun for a set from EH ? .... it used to be under 4 hun !!

I say PAY yourself almost a HUN per hour and do-it yourself. I spent about 6 or so hours on a set of 69 HP B engine ones and were more than pleased with the results.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 06:14 PM

I can get them done for $595.00 plus shipping if anyone wants some done (that's my cost, no mark up).
Posted By: CJK440

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 06:20 PM

71



72

Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 06:38 PM

BTW, I removed the heat riser assemblies from both manifolds, dyno test wil be done with a single long bolt through both of them to fill the holes.
Posted By: dOoC

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 07:22 PM

Even at 6 hun ... that is an awful lot of $$$ to just push some abrasive and clay through cast iron.
Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 07:33 PM

Quote:

Almost 7 hun for a set from EH ? .... it used to be under 4 hun !!

I say PAY yourself almost a HUN per hour and do-it yourself. I spent about 6 or so hours on a set of 69 HP B engine ones and were more than pleased with the results.




You can do the extrude hone process oh proctologist of fibberglASS ???

please elaborate
Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/01/08 07:35 PM

Chris the rib on the 72 is to hold the heat stove for the air cleaner, in case you didn't know that
Posted By: 360view

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/11/08 08:46 PM


It seems to me that you could accomplish the same as Extrude Hone with a wet sand blasting set up.

I can't remember the name now,
but I am pretty sure I had a small electric pressure washer (German ?) in the 1980s that came stock with a nozzle that would suck in sand and blast it out with the high pressure water.

a quick Google search found this:

http://www.pressureparts.com/None-C-SandBlas-Pressure-Part-391510.aspx

I admit that it would be hard to get even an extra long shank carbide burr inside some of the exhaust manifold passages but the wet sand blast nozzle should work
Posted By: Rug_Trucker

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/12/08 06:10 AM

Quote:



You can do the extrude hone process oh proctologist of fibberglASS ???

please elaborate




Well here we go again folks! Walk over to the window and look out.

FULL MOON ON TUESDAY!

FEEL THE LOVE
Posted By: I go fast

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 10/12/08 12:51 PM

If you blow enough hot air through them you can accomplish the same results.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 03:37 PM

Ok,

This just in.......

Had my 340 dyno'd this week, I don't have the dyno sheets yet but I do have a report on Extrude Honed Manifolds VS stock manifolds. With ZERO changes other than removing the EH manifolds and replacing with stock unmodified originals (both sets were nice originals of 1971 A-body 340 manifolds, one set EH, the other stone stock, bead blasted clean, no repairs, heat risers removed and blocked off).

A grand total of 4-5 HP difference basically accross the board. Pretty much what I expected.

Additional notation, removing the stock air cleaner netted an additional 8-9 HP gain using either set of manifolds.

This was on a 426 Cube stroked 340 running a hydraulic cam and pump gas friendly 9.7:1 compression, VERY stock 71 TQ carb, intake, etc. (FAST style build 340 but compromised big time by hyd cam choice and lower compression for streetability).
Posted By: 360view

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 04:22 PM

thanks for posting that rear wheel dyno result

is the 5 hp gain
with the Extrude Hone exhaust manifolds
about 1.5% or so
of the maximum horsepower?
Posted By: DPelletier

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 04:22 PM

Thanks for the update Scott, I was waiting for it!

Can you say where that motor is power wise? Obviously the manifolds would make even less difference on a smaller cubed motor. Sounds like it's not worth it except for the very few looking for every last hp and constrained to use stock manifolds.

Cheers,
Dave
Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 04:26 PM

Scott , thanks , question , what were you using for an air filter element ? Also did they just pull off the top of the air cleaner or remove it completely ?
Posted By: autoxcuda

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 04:32 PM

Quote:

thanks for posting that rear wheel dyno result

is the 5 hp gain
with the Extrude Hone exhaust manifolds
about 1.5% or so
of the maximum horsepower?




Didn't sound like a rear wheel dyno. Could you clarify, Scott?

Because the motor is built out to 426 cubes I wonder if the 1.5% might not be applicable to a smaller cube motor with less HP.

Would it be applicable to a smaller cube motor with the same HP? That motor would have to a combination of more heads, cam, etc to acheive the same HP I assume.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 04:35 PM

The dyno test was run on an engine dyno (not a Chassis dyno). I wanted the engine to be dyno'd with most accessories installed to best simulate what it would really be once installed in the car, stock air cleaner, pullies, ex manifolds etc.

Unfortunately the dyno shop only had headers available for a small block and due to this his exhaust hook ups were only for headers. Of course this didn't come up until 2 days before the run so I had to go out and have a muffler shop cobble up some ex mnfld collector adapters and short ex pipes which ended up reducing the 2.00 ex mnfld outlets to 1.75 diam tubing (pretty serious cork).

At any rate, the engine HP peaked at 439hp at just under 5,900 RPM (hyd cam or intake manifold volume being too small likely factors there) and 480 somthing ft lbs or torque.

Nothing earth shattering but a solid showing considering the build combo and the restrictive exhaust pipes. I'm thinking with some minor tuning and a good exhaust setup 450HP plus should be a no brainer once in the car. If I ever decide to go with a roller cam even more HP could be available, I built the short block to take anything I can throw at it in the future so there's a gob of room for improvments down the road.

As far as Extrude Honing and the difference it makes. I think there is a limit to gains you can expect but IMO every engine will benifit differently from it. As I've said before, you chase the bottle necks in the combo, if the bottleneck is the manifolds it will make a bigger difference and push the bottle neck to some other area needing improvment to gain more HP.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 04:38 PM

John I can't answer the AC questions yet but I'll ask, I believe it was removed completely, I also believe it was a stock filter.
Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 04:41 PM

Quote:

John I can't answer the AC questions yet but I'll ask, I believe it was removed completely, I also believe it was a stock filter.




should have tried it with a K+N , they are allowed in F.A.S.T.
Posted By: THESHAKERPROJECT

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 05:06 PM

Hey Scott, can you post the sheet...and what happened to the "15 to 20 hp" ??? You could easily loose or gain 5hp with the choice of muffler you run and on a real 340 CI motor the gains would probally be less than 5hp. I remember when Dulcich dynoed a 440 and gained 2-3 ftlb of tq with the extrude honed BB set...not really worth the effort and expence AND I hear that some exhause manifolds will crack over time. I would like to have seen that 426 run with a nice set of TTI headers as well as the manifolds.
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 05:27 PM

Keep in mind that If I were building a race or bracket engine this would have been an entirely different build.

My goals were a bit complicated but along the lines of a STOCK appearing ( all correct externals for 1971, carb, intake, exhaust, air cleaner, etc.) PUMP GAS (lower compression for safe no detonation street duty engine that would require MINIMAL maintainance (hydraulic cam, no removing valve covers, etc.). There's an outside chance that I could someday run it in a FAST event and I wanted it to be a viable canidate for that as well.

Due to all of the above I didn't run header tests, roller or solid cams, better carb or intake, high compression, etc. Of course in electing to side step all of those I walked away from a couple hundred HP as well, something I can always add or change later if I choose to do so even if I left the compression alone.

The bottome line is that if you want every available HP available to whatever combo you need to make choices with nearly every aspect of the combo, not just one item. Extrude honing is a viable choice but can result in a minimal gain for the money spent, it's not for everyone. As far as cracking due to EH them, I doubt it, you can't even see dimensional changes in the manifolds, they simply look polished inside, I doubt there is any appreciable thinning that could lead to cracking, in fact the deburring action of polishing them probably decreases the likelyhood.

This old saying comes to mind "Speed costs money son, how fast do you want to go?"
Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 07:29 PM

Quote:

Hey Scott, can you post the sheet...and what happened to the "15 to 20 hp" ??? You could easily loose or gain 5hp with the choice of muffler you run and on a real 340 CI motor the gains would probally be less than 5hp. I remember when Dulcich dynoed a 440 and gained 2-3 ftlb of tq with the extrude honed BB set...not really worth the effort and expence AND I hear that some exhause manifolds will crack over time. I would like to have seen that 426 run with a nice set of TTI headers as well as the manifolds.




Extrude Hone CLAIMED 15-20 , Scott was alot closer with his 5-10 guess

Why am I not surprised to see the unrealistic claims from someone taking your hard earned cash?

Reminds me of someone else
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 07:39 PM

Ok, have some filter info. No filter was used, just an empty air cleaner (with the top secured all the way down),then it was removed completely for the second test.

*FWIW had I known this I would have requested a run with a K&N but it was over by the time we discussed it.
Posted By: THESHAKERPROJECT

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 09:04 PM

Yes, that was the point. Mimimal gain for the expense. Maybe Extrude Hone should offer the intake and exhaust manifolds as a pkg deal and then maybe 10-15 hp they quoted would be more realistic. My engin builder would not send them my set because a costomer came back to his shop with a cracked set of BB exhaust manifolds.
Posted By: scatpacktom

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/13/08 10:51 PM

4 to 5 hp...HUH, Who knew?

I sure never saw sh t thats for sure
Posted By: Silverbullet2

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/14/08 11:26 AM

I remember a few years ago a back to back EH vs non EH test was done on Dudek's Hemi Challenger. The gain with EH was something like 4-5 hp, BUT testing showed the EH maifolds leaned out the motor slightly. After re-jetting the gain was more like 12-15. Still a pretty dang expensive 12-15 hp anyway you wanna look at it. Sounds like those guys need some competition in the marketplace.
Posted By: DaveDudek

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 01:41 AM

I think I picked up a total of 12HP on a "back to back" test. That was on a 12 to 1, 484 cubed Hemi.
Posted By: Michael

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 01:57 AM

A car has to run faster with EH because your wallet is lighter
Posted By: RapidRobert

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 02:02 AM

Doug Dutra cast some new split /6 exhaust manifolds from scratch. For that kind of money a person could almost recast a set with a bigger ID. Just thinking out loud
Posted By: 360view

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 01:09 PM

if the post-Extrude Hone manifolds are still off the engine and available,
perhaps it would be a good idea to make some templates of the port shapes the EH process created?

if these templates were then scanned and added to the archives,
perhaps other factory manifold owners using a grinder could be very close to the gains found?
Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 02:07 PM

Quote:

if the post-Extrude Hone manifolds are still off the engine and available,
perhaps it would be a good idea to make some templates of the port shapes the EH process created?

if these templates were then scanned and added to the archives,
perhaps other factory manifold owners using a grinder could be very close to the gains found?




how do you get to the areas that you can't even SEE ??

the extrude hone process mostly SMOOTHES (polishes) the internal surface of the manifold .
Posted By: DPelletier

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 04:17 PM

Quote:

I think I picked up a total of 12HP on a "back to back" test. That was on a 12 to 1, 484 cubed Hemi... making Huge power .




There; I fixed that for you.



Dave
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 04:51 PM

Quote:

Doug Dutra cast some new split /6 exhaust manifolds from scratch. For that kind of money a person could almost recast a set with a bigger ID. Just thinking out loud




Well, I don't know if that would work or not, but let's say for a minute that it would, if you can get a set of (outwardly accurate, internally larger) exhaust manifolds cast for $600.00 please sign me up!

Posted By: JohnRR

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 04:55 PM

scott I didn't notice , do you have a before and after weight from the honed manifolds ?
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 05:00 PM

No John, but I bet it's not much of a difference, I can weigh the two sets I tested when I get them back but due to variability it won't be an accurate comparison.


As far as Dudeks Hemi picking up 12HP, I have no doubt that he did, as I said above:

I think there is a limit to gains you can expect but IMO every engine will benifit differently from it. As I've said before, you chase the bottle necks in the combo, if the bottleneck is the manifolds it will make a bigger difference and push the bottle neck to some other area needing improvment to gain more HP.

His combo obviously needed more exhaust flow and the EH process helped his engine in that respect more than it helped mine.
Posted By: DPelletier

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 05:27 PM

Quote:



As far as Dudeks Hemi picking up 12HP, I have no doubt that he did, as I said above:

I think there is a limit to gains you can expect but IMO every engine will benifit differently from it. As I've said before, you chase the bottle necks in the combo, if the bottleneck is the manifolds it will make a bigger difference and push the bottle neck to some other area needing improvment to gain more HP.

His combo obviously needed more exhaust flow and the EH process helped his engine in that respect more than it helped mine.




True enough, but when you consider the power his FAST Hemi is making it's not that far off (percentage wise) as 5-6hp on a 400hp motor.

I'd be interested to see how the big block HP manifolds flow compared to your stock small block ones. After all at the same hp levels it's all about CFM, right? My guess is that on my 440-6 PS motor, I'd see even less of a gain than your 4-5hp.

Dave
Posted By: ScottSmith_Harms

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 05:33 PM

Could be Dave, pure guesswork at this point.
Posted By: DPelletier

Re: Anyone Use Extrude Hone for Exhaust Manifolds? - 11/18/08 06:29 PM

Quote:

Could be Dave, pure guesswork at this point.




That's a fact. I think I'll spend the money on the best TTI system and quality mufflers. I'm ALMOST positive that will be money better spent.

I'm not knocking you or anyone else that wants every possible advantage. Actually in my case, extrude honing isn't PS legal anyways.

Dave
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