sprintcar57

Hi All,

Looking at building a LS1 engine for a Sprint Car to compete against ASCS 360 engines that make around 650hp. Car must meet minimum rules, no break given for LS engine.

Here are the rules
LS1 360 Sprintcar Engine Specs from SCCA Rule Book

a) only LS1 standard blocks allowed
b) must be standard stroke length
c) may be 30 oversize bore
d) must have flat top pistons
e) after market cranks allowed (No lightweight cranks allowed)
f) after market rods allowed (no tie or lightweight rods allowed)
g) only hydraulic roller cam shafts allowed
h) only LS1 cylinder head allowed, must have cathedral ports
i) only stainless valves allowed
j) must have a wet sump oil system
k) must have a 4 barrel throttle body injector
l) must run on methanol
m) must run a timing chain.
n) only a run a MSD 6ALS module=startSo questions are how much can you deck the heads to bump up compression?

How much will a fully ported SL1 cylinder head make?

Do people think that the above engine would be competitive against a strong ASCS 360 engines.

Cheers

G Atsma

One thing- you will NEVER bore an LS1 .030 over. .010 MAX

Che70velle

iTrader: (6)

G Atsma

IF all LS blocks are allowed, THEN an iron block could be bored .030 over as per the rules. I would bet any LS block is allowed since LS1 blocks are harder to find now days.

BCNUL8R

iTrader: (2)

Seems like they don't want LS motors involved since others are allowed after market heads like Brodix and lightened parts including block and crank.

Che70velle

iTrader: (6)

G Atsma

I agree with this. Though the LS is extremely competent in stock form, WAY more so than the SBC, the truth is there is SO much dedicated circle track stuff already developed for the SBC, it's hard to justify the LS, for which there is NOT YET the same amount of development. It WILL come, but not yet....

sprintcar57

Rules definately mean alloy ls1 346 blocks only. Must retain standard stroke crank. So cant stroke engine.

A new 360 engine over here is 67k, just seeing if possible to build a 600hp ls1.

sprintcar57

What is the max hp a fully ported ls1 241 head produce?

G Atsma

Which heads are the SBC engines allowed to run? Stock 350 castings?

sprintcar57

Brodix 11x heads ascs heads.

18 degree 225cfm, 64cc.

G Atsma

So SBC's are allowed aftermarket racing heads but LS's have to run stock 241 heads??? Something is VERY wrong with this picture.....
You keep referring to "LS1" engine parts. That was only one type of LS engine, but as was mentioned above, many people use "LS1" as a generic term for ALL LS engines.
I find it tough to believe that you would have to run STOCK LS1 (241) heads when SBC's are allowed Brodix racing heads.

sprintcar57

Yeah its the first time the 5.7 ls1 style engine is allowed out here in Australia.

I know the sbc will make more power, best cars have 680hp. Just wondering if the ls1 can even remotely get near 600

LLLosingit

iTrader: (4)

The ASCS spec head was supposed to be a way to try to keep costs under control and keep competition on a level playing field, The fact is people who have it are still spending the money just in other parts of the engine and driveline to get even a small advantage, Hell just the Kinsler Dragon Claw Injection is around 4k now and a competitive engine used to in the $15,000 range 10-15 years ago is now $35,000+

There are a few series that run LS based engines now, Knoxville raceway was supposed to go to an all LS3 based class next year but postponed it for another year. They have been running a LS based engine in the 305 class I'm just not sure if it's this same engine linked ahead. They have their own Knoxville legal sealed crate available at Pace GMP-19331563-KX - Pace "Evolution CT525" Sprint Car Engine Knoxville Package
I will also add that the same basics that apply to a SBC to make them live in that environment apply to the LS based engines, It's a new platform yes but not that different and many of the same tricks to make power are the same. In an unlimited no rules environment they have a way to go to get every last ounce of power and still last more than one night but if you have the money their are plenty of builders who will spend it for you lol

LLLosingit

iTrader: (4)

I would get clarification on a few things.
1 At what weight is the crankshaft considered lightweight, Is there a minimum weight
2 Are sleeved blocks allowed
3 Can heads be angle milled
4 Can blocks be lightened

I believe they can be competitive if you have the budget and the right engine builder. In the states there is a big difference in your basis ASCS legal 360 engine that many of the teams run versus what the fully sponsored race teams use, Both engine can be competitive on a smaller track or a larger flat style or dry slick track. At larger tracks with good traction like Knoxville you can't expect to be a top 10 car if you don't have one of the best engines in the class.

sprintcar57

Must use standard ls1 block, but yeah they can be resleeve.

Yes heads can be angle milled

I would say sommething ultra lightweight would be a no no. If the engine must use hydraulic lifters obvioisly the max rpm is capped near 7200rpm.

The tracks we have are 3/8 banked or flat to 1/4 banked. Most get slick after 1st round of heats, no time trials here.

Che70velle

iTrader: (6)

rednari2

iTrader: (1)

No there is nothing wrong, OE 241s flow at about 220, so its in the same park. 55-86 heads, and this is the double hump heads, flowed at about 160. 87-95 fast burns about 180, and 96 -03 vortecs about 200. All can be ported of course, but these are the OE numbers.

G Atsma

Alright, good points! Thank you! Shows how good LS heads are...

rednari2

iTrader: (1)

They are good heads. But, keep in mind that some of the splayed valve 13* sbc heads flow upto 400. Dart has worked hard on those heads. The key to LS power is that the production head designs make good power. The designs flows well and are strong, durable, and cheap to produce.