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Re: Mallory Unilite timing issue [Re: sgcuda] #2488599
04/27/18 10:08 AM
04/27/18 10:08 AM
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BaldwinCarbs Offline
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The delay is in the electronics themselves such as an msd box or the orange Mopar box
Different brands have different delay. Example, pertronix has about a 2 degree delay @ 5,000 rpm
Msd has a 4 degree delay @ 5,000 rpm so you can curve the distributor to counter act the delay.
Orange Mopar box, about 7 degrees
GM HEI about 2 degrees with a factory module, 7 degrees with these aftermarket ones

Engines produce more torque and hp through the rpm range with a correct curve in them anyways due to piston speed vs combustion chamber design, so we curve the distributor to accommodate the delay also.







Last edited by BaldwinCarbs; 04/27/18 10:09 AM.
Re: Mallory Unilite timing issue [Re: BaldwinCarbs] #2488605
04/27/18 10:37 AM
04/27/18 10:37 AM
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Mt Morris Michigan
mopar dave Offline
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Thats the piont i was trying to make in an earlier post about how much power is lost thru out the curve if your timing is locked out. Didnt get a good answer on that at the time. But it is easier to just lock it out and forget about it. I was just curious to how much could possibly be left on the table thru the rpm band with a pump gas 511 without a curve built in. How do you figure best curve?

Last edited by mopar dave; 04/28/18 12:59 PM.
Re: Mallory Unilite timing issue [Re: mopar dave] #2488614
04/27/18 11:02 AM
04/27/18 11:02 AM
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BaldwinCarbs Offline
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If you ever run one with the correct curve, you would never lock out or put it at all in by 2,000 again!
That's how much is lost!
My personal daily driver
66 Mopar 383 4bbl Holley
4200 pounds 2.78 rear gear
Factory a/c
20mpg highway while running antique RV2 a/c

Curve is determined by camshaft, compression, and cylinder head design.

Re: Mallory Unilite timing issue [Re: mopar dave] #2488617
04/27/18 11:06 AM
04/27/18 11:06 AM
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BaldwinCarbs Offline
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Originally Posted By mopar dave
Thats the piont i was trying to make in an earlier post about how much power is lost thru out the curve if your timing is locked out. Didnt get a good answer on that at the time. But it is easier to just lock it out and forget about it. I was just curious to how much could possibly be left on the table thru the rpm band with a pump gas 511 with a curve built in. How do you figure best curve?


What's your setup?

Re: Mallory Unilite timing issue [Re: BaldwinCarbs] #2488643
04/27/18 11:55 AM
04/27/18 11:55 AM
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Mt Morris Michigan
mopar dave Offline
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511 with 4.375 bore, 11.25: static comp, mw victors with 330cc port flow 356@.650, solid flat tappet 270/276@50-.644/.615-110 installed 106, 1100 dominator, 2" header, 3400# car with 5000 stall.

Re: Mallory Unilite timing issue [Re: mopar dave] #2488675
04/27/18 01:01 PM
04/27/18 01:01 PM
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BaldwinCarbs Offline
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Originally Posted By mopar dave
511 with 4.375 bore, 11.25: static comp, mw victors with 330cc port flow 356@.650, solid flat tappet 270/276@50-.644/.615-110 installed 106, 1100 dominator, 2" header, 3400# car with 5000 stall.


Run a factory distributor with 2 of the big factory springs that have the big loop in the end. Keep in mind you have to have matching springs with about a .051 wire diameter and a distributor machine.
You'll be at 24 degrees initial
26@ 2,000
28@ 3,000
30@ 4,000
32@ 5,000
34@ 6,000

Re: Mallory Unilite timing issue [Re: BaldwinCarbs] #2488686
04/27/18 01:37 PM
04/27/18 01:37 PM
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Phila. Pa.
Mattax Offline
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Originally Posted By BaldwinCarbs
The delay is in the electronics themselves ...

So glad you are posting about this. I felt like I was the only one here. And although I'm sure that's not quite true, it does seem like a secret. A stock class racer first told me about how the car always slower when they took out that heavy secondary spring from the DC distributor. I didn't learn the real reason for most of the delay until much later.

This is the reason for the solid line and the dashed line in the Direct Connection graph in post #11 here:
https://www.forabodiesonly.com/mopar/thr...post-1972040585
In theory the timing could increase (depending on the spring perch setting) but on a slow ECU, its flat, which is still a hell of a lot better than losing timing.

They set up the heavy spring and weights to counteract the delay in electronic switching (sometimes called slew rate). Every electronic operation takes time.

This secondary portion of the advance can't be done with all advance mechanism. That's with the MSD, my suggestion for Dave was to set it up to delay the 'all in' to a higher rpm. That way the slew will have less effect through the top of your power curve.
https://www.tapatalk.com/groups/racingfu...-less-t765.html

More links on slew in Innova 3568 Timing Light, now slew rate

Re: Mallory Unilite timing issue [Re: Mattax] #2488718
04/27/18 04:31 PM
04/27/18 04:31 PM
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Originally Posted By Mattax
Originally Posted By BaldwinCarbs
The delay is in the electronics themselves ...

So glad you are posting about this. I felt like I was the only one here. And although I'm sure that's not quite true, it does seem like a secret. A stock class racer first told me about how the car always slower when they took out that heavy secondary spring from the DC distributor. I didn't learn the real reason for most of the delay until much later.

This is the reason for the solid line and the dashed line in the Direct Connection graph in post #11 here:
https://www.forabodiesonly.com/mopar/thr...post-1972040585
In theory the timing could increase (depending on the spring perch setting) but on a slow ECU, its flat, which is still a hell of a lot better than losing timing.

They set up the heavy spring and weights to counteract the delay in electronic switching (sometimes called slew rate). Every electronic operation takes time.

This secondary portion of the advance can't be done with all advance mechanism. That's with the MSD, my suggestion for Dave was to set it up to delay the 'all in' to a higher rpm. That way the slew will have less effect through the top of your power curve.
https://www.tapatalk.com/groups/racingfu...-less-t765.html

More links on slew in Innova 3568 Timing Light, now slew rate


Yes, that's half of it. It's not really a secret, just to many people read to much of the internet and drink the koolaid!
It's all marketing.
The other half of it is the get the correct timing at a given rpm.
A 906 Mopar head will not make it's most power at 4,000 with timing set at 38

A 15 degree Brodix head wants like 22 degrees at 4,000 rpm and 28 degrees at 7,000 if that tells you anything

With a locked out distributor you have a backwards curve when you add in the slew rate, so the motor is off at all rpms

A 602 GM crate motor makes max power at 34 degrees. So when these guys lock their distributors out and run them on the dyno they have to set the timing to 39 degrees to get max power. Well 39 - 5 degrees of slew rate = 34
But this destroys power below the max power rpm

Re: Mallory Unilite timing issue [Re: sgcuda] #2488728
04/27/18 05:21 PM
04/27/18 05:21 PM
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LOL, you forgot few variables to add to the timing curve.
At peak volumetric efficiency (just past peak torque) needs the least amount of timing.
As volumetric efficiency is decreased more timing is needed.
At piston acceleration speed goes up (low gear) more timing is needed.

FYI I would love to locate a old distributor machine

Joe


Without Data, you’re just another guy with an opinion.
Re: Mallory Unilite timing issue [Re: sr4440] #2488729
04/27/18 05:23 PM
04/27/18 05:23 PM
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Originally Posted By sr4440
LOL, you forgot few variables to add to the timing curve.
At peak volumetric efficiency (just past peak torque) needs the least amount of timing.
As volumetric efficiency is decreased more timing is needed.
At piston acceleration speed goes up (low gear) more timing is needed.

FYI I would love to locate a old distributor machine

Joe



That's pretty much what I've been explaining in a nutshell lol
Just in simple common internet terms lol
I'm afraid of talking over people's heads and them losing interest because they can't understand the terminology

Last edited by BaldwinCarbs; 04/27/18 05:25 PM.
Re: Mallory Unilite timing issue [Re: BaldwinCarbs] #2488770
04/27/18 07:03 PM
04/27/18 07:03 PM
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Originally Posted By BaldwinCarbs
Originally Posted By sr4440
LOL, you forgot few variables to add to the timing curve.
At peak volumetric efficiency (just past peak torque) needs the least amount of timing.
As volumetric efficiency is decreased more timing is needed.
At piston acceleration speed goes up (low gear) more timing is needed.

FYI I would love to locate a old distributor machine

Joe



That's pretty much what I've been explaining in a nutshell lol
Just in simple common internet terms lol
I'm afraid of talking over people's heads and them losing interest because they can't understand the terminology



Then spell it out. What makes you think we are too stupid to understand what you are saying? It might be you don't express yourself well.


Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
Re: Mallory Unilite timing issue [Re: madscientist] #2488777
04/27/18 07:19 PM
04/27/18 07:19 PM
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Originally Posted By madscientist
Originally Posted By BaldwinCarbs
Originally Posted By sr4440
LOL, you forgot few variables to add to the timing curve.
At peak volumetric efficiency (just past peak torque) needs the least amount of timing.
As volumetric efficiency is decreased more timing is needed.
At piston acceleration speed goes up (low gear) more timing is needed.

FYI I would love to locate a old distributor machine

Joe



That's pretty much what I've been explaining in a nutshell lol
Just in simple common internet terms lol
I'm afraid of talking over people's heads and them losing interest because they can't understand the terminology



Then spell it out. What makes you think we are too stupid to understand what you are saying? It might be you don't express yourself well.


Just trying to simplify things for everyone
The newbies and the veterans

Re: Mallory Unilite timing issue [Re: sgcuda] #2488794
04/27/18 07:51 PM
04/27/18 07:51 PM
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Put it out there and let everyone learn at their own pace.

What you posted came off as incredibly arrogant.


Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
Re: Mallory Unilite timing issue [Re: madscientist] #2488797
04/27/18 07:58 PM
04/27/18 07:58 PM
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BaldwinCarbs Offline
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Originally Posted By madscientist
Put it out there and let everyone learn at their own pace.

What you posted came off as incredibly arrogant.


Not intended that way at all
Amazing how that can happen over a keyboard lol

Re: Mallory Unilite timing issue [Re: sgcuda] #2488798
04/27/18 07:58 PM
04/27/18 07:58 PM
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Seems like everyone here is barking up the wrong tree.
I’ll ask again... is it a capacitive discharge/ multiple spark system?


"use it 'till it breaks, replace as needed"
Re: Mallory Unilite timing issue [Re: TRENDZ] #2488801
04/27/18 08:07 PM
04/27/18 08:07 PM
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Originally Posted By TRENDZ
Seems like everyone here is barking up the wrong tree.
I’ll ask again... is it a capacitive discharge/ multiple spark system?


I take it your question is about what system has a delay?

Re: Mallory Unilite timing issue [Re: sgcuda] #2488802
04/27/18 08:12 PM
04/27/18 08:12 PM
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Mattax Offline
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Relax. It's usually best to keep things to the thread. I know it was starting to drift, but it will come up again. He posted what was relevant to the question. Lets either start a new thread about timing or wait until it comes up for some specific application.

As far as distributor machine, there's a fella in Halifax Pa that's been restoring Sun machines - and there's another guy in the midwest that restores Allens and Sun distributor machines. Let me know if you need more specifics on either.

Re: Mallory Unilite timing issue [Re: BaldwinCarbs] #2488833
04/27/18 10:01 PM
04/27/18 10:01 PM
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The
Originally Posted By BaldwinCarbs
Originally Posted By TRENDZ
Seems like everyone here is barking up the wrong tree.
I’ll ask again... is it a capacitive discharge/ multiple spark system?


I take it your question is about what system has a delay?



No. It’s about the fact that most dial back timing lights will not trigger correctly with any system that has more than one spark per engine cycle. They get especially finicky at the transition from multiple to single. I don’t know how many times I see this brought up.
His “problem” went away with the change to a standard timing light. Any other delay that happens prior to the spark discharge is irrelevant if your equipment is lying to you.


"use it 'till it breaks, replace as needed"
Re: Mallory Unilite timing issue [Re: TRENDZ] #2488834
04/27/18 10:04 PM
04/27/18 10:04 PM
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Originally Posted By TRENDZ
Seems like everyone here is barking up the wrong tree.
I’ll ask again... is it a capacitive discharge/ multiple spark system?

If you are asking about the car I have been working on, as the title says, it's a Mallory Unilite. Not a CD or a MSD system, Just a regular HEI using optical sense instead of magnets.

Re: Mallory Unilite timing issue [Re: BaldwinCarbs] #2488836
04/27/18 10:10 PM
04/27/18 10:10 PM
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Originally Posted By BaldwinCarbs
A 15 degree Brodix head wants like 22 degrees at 4,000 rpm and 28 degrees at 7,000 if that tells you anything

With a locked out distributor you have a backwards curve when you add in the slew rate, so the motor is off at all rpms


Interesting you mentioned Brodix 15 degree heads. I am building a 605 with B1 originals. High compression, drag race only. This will be in a lightweight stick shift car. RPM range will be 4,500 to 7,500. Maybe a little higher. How would you go about setting up a curve for higher rpm, or is it needed at these speeds.

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