I have been thinking about building a sportsman dirt car but I am wanting to go against the traditional sbc engines that most put in there cars. Below I have listed the engine rules and would appreciate any input you guys may have. I was thinking of building a 6.0 iron block but that would exceed the maximum cubic inch allowed unless I destroked the engine. My primary concern would be head selection. I don't know much about the iron heads on the ls engines and haven't been able to find much information about them. Although it would be easier to follow the traditional concept of sbc I am trying to think outside the box and I like the reliability of ls engines. I have also considered using a 5.3 block and bore the engine out as much as possible. I will need to find a combination that can turn 7-8000 rpm consistently. Race gas is permitted so it will not be a problem to run 110+ octane. Thanks for all the help and hopefully you guys will be able to help me with my quest.




ENGINE:
A. 362 cubic inch maximum, including over bore.
B. Any steel crankshaft.
C. Stock stroke.
D. Any steel connecting rods.
E. Stock type pistons, 2 or 4 eyebrow, may be forged.
F. Dry sumps allowed.

HEADS:
A. Steel heads. Must be based on OEM design (Chevy, World, Dart, and Pro are OK).
B. 23 degree heads are OK. NO 14 degree heads allowed!
C. Intake and exhaust bolt pattern must match original OEM head.
D. Valve angle and valve spacing must meet OEM specs for the head being used.
E. Steel valves only. Undercut stems permitted. NO titanium valves.
F. Valve stem diameter 11/32 inch minimum for all engines.
G. Maximum valve size: Intake – 2.055 ; Exhaust – 1.625.
H. NO porting or polishing.
I. Three(3) angle racing valve job permitted. Machine cuts only.
J. Any valve springs, retainers, roller rocker arms, and stud girdles allowed.

CAMSHAFT:
A. Flat tappet only. NO roller cams.

DISTRIBUTOR:
A. Stock type or magneto allowed.

CARBURETOR:
A. 750 CFM maximum.
B. Any intake manifold.
C. Gasoline only.

 

hard to find steel heads for ls engines anymore. I would prolly go with the sbc because it just seems like it will be to hard to make the ls1 fit those rules. kinda seems those rules are set up for sbc's and sbf's

 

Well, I am certainly on your side. I think it would be neat to see an LS series engine in a dirt car. There are 2 big problems that I see right away.

1st: Your idea of using a 6.0L block and then destroking it would not work because those rules you posted specifically state "Stock Stroke".
2nd: Flat tappet camshafts only. I do not even know if you can get a flat tappet cam for an LS engine.

It appears that the track/promoter would have to make some pretty big changes to the rules to allow LS based engines, but it would be cool if they did. I think you would have an advantage on them until the competitors caught up.

 

Yeah, I think boring a 5.3 engine will probably be my only option when it comes to engine selection. I am not sure if there is a misprint on ebay but I just did a quick search and there is supposedly a flat tappet cam for the ls1 made by lunati voodoo series. I've always been a huge fan of the ls series engines but its been impossible to even get the slightest interest out of anyone that I have mentioned it to. I actually helped build a 93 z28 for a smaller dirt track and its first night out it lapped all but 2nd place lol. It was crazy seeing a fbody with wide dirt track tires but the car was on a rail. Two weeks later the car was banned from street class for lack of competition and something about it being fuel injected I don't see having that sort of edge with this idea but any advantage that can be found is well worth the effort of trying. Does anyone even make steel aftermarket heads? If the idea sticks, pending officials outlook on something different, it could open up a whole new market for the ls engines. Especially after hearing how much super late model drivers pay for their engines, a full aluminum ls engine would be a very cheap alternative.

 

Personally I would stick with the sbc for a dirt track car, mainly because parts are easy to come by. You may go through a couple of motors in a season & it is much easier to just throw in another sbc. Plus if you end up at a track that has an engine claim or engine swap rule you could find yourself having to put in a lot more effort to get back out there depending on your budget.

 

I always thought this would be a good idea. Doesnt world products make a sbc style block that fits LS heads? Thought that would be awesome.

 

Yeah but you will still have to find the rare steel heads... and you can port them... I dont know if it is worth it...

 

Heads is becoming the difficult thing to find. The cheapest route as far the block goes will be taking a 5.3 block and bore it out to a 5.7. There are some blocks on ebay right now for $99 plus shipping. They are new seconds but they said most need to be bored which will be done anyways. Does anyone make a performance steel head for the ls series? I can find take offs here and there but would prefer an aftermarket head if possible. Does anyone know any flow numbers on stock steel heads? I cant find any information on them anywhere.

 

But least cheaper bottom end i would imagine. and if you find a steel head they design of them alone would gain power compared to a SBC head.

 

look for a 99-01 lq4 they came with iron heads.

 

LS engine won't work period under those rules.

23º degree valve angle...... FTL.
11/32 valves.... FTL.

They pretty much cornered you into running SBC.

Other issue with LS engine, while you're allowed to run dry sump under those rules, the oil pump spins at 1:1 on the crankshaft, in SBC oil pump runs off the camshaft at 50% of engine rpm. OE LS style oiling will cavitate the oil over say 7500rpm

I'd be looking to run a SBC, theirs a couple loop holes in those rules, ie no specifics on the crankshaft, many of these organizations specifically say, "standard weight 48lbs stock stroke crankshaft only". No mention in your rules for crankshaft, Eagle has a 3.48" stroke honda rod journal lightweight 45lbs crank. No limit on compression ratio? Hollow valves?

 

Pretty much all of your rules say "No LS Engines."

 

I have a IMCA Stockcar we are putting a stock 5.3 vortec in and going racing if any has intrest let me know.

 

Use a Gen I motor anyway. The parts are more available and cheaper.

 

This thread is almost 7 years old...

 

Brzezinski Racing here in Pewaukee, WI are cast iron experts of the stock car world
I've seen some of their work to the early 6.0 iron cylinder heads and it's pretty neat stuff for sure......www.castheads.com
Also Wagner automotive racing in Markesan,WI makes/sells a front timing cover which has both front mount distributor/drive AND mechanical fuel pump which is quite mandatory in most racing sanctions.

 

Yep! Guess I started something.

 

Thank you for your valuable insight

 

I left a set of iron 6.0 heads behind a few weeks ago when I bought a 6.0, I didn't even bother with them . Just took the block. Never had use for them.