LS/circle track?
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LS/circle track?
Our track is allowing 5.3 LS and wondering what I can do to get the most out of a stock internal engine. The rules are…
3150 min weight
Stock untouched internals 5.3,
CT525 cam allowed
Max 6200 rpm(rev limit)
Aftermarket MSD ignition allowed
Untouched 4412 Holley on dual plane intake,
Headers allowed
Pump gas
Powerglide or 3 spd Saginaw trans but with stock size flywheel/clutch, or converter.
3150 min weight
Stock untouched internals 5.3,
CT525 cam allowed
Max 6200 rpm(rev limit)
Aftermarket MSD ignition allowed
Untouched 4412 Holley on dual plane intake,
Headers allowed
Pump gas
Powerglide or 3 spd Saginaw trans but with stock size flywheel/clutch, or converter.
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Re: LS/circle track?
I would get a "All-Pro" sprint car front cover and use a distributor with a crank trigger for an MSD 7AL2 Plus ignition.88bluestar wrote: ↑Sat Aug 13, 2022 12:34 pm Our track is allowing 5.3 LS and wondering what I can do to get the most out of a stock internal engine. The rules are…
3150 min weight
Stock untouched internals 5.3,
CT525 cam allowed
Max 6200 rpm(rev limit)
Aftermarket MSD ignition allowed
Untouched 4412 Holley on dual plane intake,
Headers allowed
Pump gas
Powerglide or 3 spd Saginaw trans but with stock size flywheel/clutch, or converter.
http://www.rmcompetition.com
Specialty engine building at its finest.
Specialty engine building at its finest.
Re: LS/circle track?
Check deck and possibly mill to get comp up, I’m sure there’s room to improve. Do they allow boring at all or does it explicitly say stock bore size? Do they only allow that specific cam number or that size? Someone like mr Jones could help with.
Re: LS/circle track?
I seriously disagree with running a distributor, your paying well over $1k for the front timing cover and distributor for an inferior setup in some ways.
MSD6014 box is $400
If your talking max effort (in homework/dyno time) you would want to do individual cylinder timing and a custom timing curve. More than anything this will be where you gain the most area under the curve in my opinion.
I would generally copy the 605 crate engine as far as carburetor and air cleaner, they have those things pretty well figured out.
Tighten up the clearances to run 0W20 or 5W20, invest in a quality pan scraper and windage tray, minimize windage losses.
Headers should to be small, like 1.5" or 1.625" with a smaller 2.5" collector.
I would not recommend thinner head gaskets, spec is .010 above the deck and gasket is .053 (or so) compressed.
If you have slight allowances for different cylinder head castings there is room here for gains.
If there are no rules on a vacuum pump you need to run one, pin oilers would be a good idea at that point.
Rocker arms pivots should be installed if not against the rules.
Run a small diameter balancer, Corvette style would even work.
Valve seat angles can allow for some gains but you need to experiment or find someone who has.
Bottleline there are a ton of things you can do, how many you can afford and the boundaries your will to push will dictate the rest.
MSD6014 box is $400
If your talking max effort (in homework/dyno time) you would want to do individual cylinder timing and a custom timing curve. More than anything this will be where you gain the most area under the curve in my opinion.
I would generally copy the 605 crate engine as far as carburetor and air cleaner, they have those things pretty well figured out.
Tighten up the clearances to run 0W20 or 5W20, invest in a quality pan scraper and windage tray, minimize windage losses.
Headers should to be small, like 1.5" or 1.625" with a smaller 2.5" collector.
I would not recommend thinner head gaskets, spec is .010 above the deck and gasket is .053 (or so) compressed.
If you have slight allowances for different cylinder head castings there is room here for gains.
If there are no rules on a vacuum pump you need to run one, pin oilers would be a good idea at that point.
Rocker arms pivots should be installed if not against the rules.
Run a small diameter balancer, Corvette style would even work.
Valve seat angles can allow for some gains but you need to experiment or find someone who has.
Bottleline there are a ton of things you can do, how many you can afford and the boundaries your will to push will dictate the rest.
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Re: LS/circle track?
Inferior in almost every way except horsepower, when using a crank trigger and a carburetor.
http://www.rmcompetition.com
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Re: LS/circle track?
If you are losing horsepower with a coil on plug setup over a distributor in an application like this you have no business near the laptop.Walter R. Malik wrote: ↑Sun Aug 14, 2022 1:43 pmInferior in almost every way except horsepower, when using a crank trigger and a carburetor.
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Re: LS/circle track?
Reality sucks, doesn't it.RNorton84 wrote: ↑Sun Aug 14, 2022 2:56 pmIf you are losing horsepower with a coil on plug setup over a distributor in an application like this you have no business near the laptop.Walter R. Malik wrote: ↑Sun Aug 14, 2022 1:43 pmInferior in almost every way except horsepower, when using a crank trigger and a carburetor.
I have run that MSD coil near plug Inductive ignition back to back to back against the crank triggered, capacitive discharge 7AL2+ ignition and I will believe the results over what I may think, every time.
You are certainly free to believe whatever you want.
Now, using a 16 volt system may be different.
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Re: LS/circle track?
I will believe what physics and experience tells me, the spark plug doesn't care what fires it as long as the energy is sufficient and timing are in line for best power. Spending $2,000 on the ignition system is pointless, even without the potential rules issues of a crank trigger which usually is illegal. At this power level stock coils will easily meet the spark levels required for proper combustion. The money spent there would be much better spent on things that will actually produce more power like oil, carb, oil pan etc.
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Re: LS/circle track?
Again ... you are free to believe whatever you wish.RNorton84 wrote: ↑Sun Aug 14, 2022 8:44 pm I will believe what physics and experience tells me, the spark plug doesn't care what fires it as long as the energy is sufficient and timing are in line for best power. Spending $2,000 on the ignition system is pointless, even without the potential rules issues of a crank trigger which usually is illegal. At this power level stock coils will easily meet the spark levels required for proper combustion. The money spent there would be much better spent on things that will actually produce more power like oil, carb, oil pan etc.
I think that LS ignitions and the LS aftermarket ignitions which use coil near plug employ "crank triggering". It is simply in an out of site location.
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Re: LS/circle track?
Indeed they do, but crank triggers are generally against the rules in most of the lower classes with small block chevy/ford style engines that require distributors.
So it would be asking for trouble to actually run a bonified racing style crank trigger, especially if you start winning.
So it would be asking for trouble to actually run a bonified racing style crank trigger, especially if you start winning.
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Re: LS/circle track?
The only improvement I would see in an aftermarket crank trigger over the OEM one is if you would need to adjust the timing with the crank trigger. In fact from a quality and how clean the signal is, the few I have had on a scope the OEM is better anyway. As long as the ignition box you are using will let you set the timing, I would not waste the money.
Re: LS/circle track?
it's the box that makes the horsepower difference, hard to believe the trigger function makes any effect at such low rpm, did you run it with just a distributor triggering?
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Re: LS/circle track?
Tried it and sometimes it did improve and other times it was the same.
The total timing would jump around about 4 degrees ...
I surmise it was because there was no oil pump to smooth out /dampen the variance/scatter of the gear teeth or timing chain.
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