LS race engine build questions

[DAlgozine]

Planning to build an LS based race engine for a 2000 Camaro. Road race car for NASA (National Auto Sports Association), American Iron class. Basic rules are engine mods are open, but need to meet a 9.5 to 1 HP to weight ratio and 9 to 1 TQ to weight. Which means, car and driver weigh approximately 3200, give or take a few:

Crank Rear wheels
380 HP 335 HP
400 TQ 350 TQ

Originally I was going to build an LS1 based engine, but resently have been looking at using one of the aluminum 5.3 based engines for a couple reasons.
1) The smaller displacment will better match the HP and TQ I'm looking for. 5.7 engines typically need to be de-tuned when running headers
2) The IV gen engines have improved oiling system over the III Gen's

So, any imput on which family of LS engine parts to piece together, ie. block, heads, cam, crank and rods to use?

[DAlgozine]

I'll rephase the question:

Which 5.3 alumium block is available for rear wheel drive cars?

Any sources to find these blocks?


Dave

[mark21742]

I'll rephase the question:

Which 5.3 alumium block is available for rear wheel drive cars?

Any sources to find these blocks?


Dave

a stock ls1 with an ls6 intake will be very close to the specs your looking for. can you have more power than the 380 crank, or is that the max limit for the class your wanting to run?

[DAlgozine]

a stock ls1 with an ls6 intake will be very close to the specs your looking for. can you have more power than the 380 crank, or is that the max limit for the class your wanting to run?

Thanks for the response.
A few guys in my class have used an LS1. Most have to de-tune to be legal. Just imporving intake and headers and the LS1 is at, or over the limits. HP and TQ are governed based on the weight of the car. However, we can add ballast.

I know the 5.3 can easily make the HP and TQ I need and I want to take advantage of the Gen IV block imporvents, which also has a better oiling system.

I've done some more research and came up with the following:

"Generation IV 5.3L Engines

Introduced in 2005, Generation IV Vortec 5300 engines offer several improvements over their Generation III counterparts. General Motors currently offers 2 iron block versions (LY5 and LMG) and 2 aluminum block versions (LH6 and LC9). All versions feature the GM Active Fuel Management system, formerly known as displacement on demand. All Gen-IV 5.3L engines feature drive-by wire throttle control and may require the throttle pedal for the engine to run."

I've been racing a Mustang for a few years, so I'm not up on my GM / LS engines. I was hoping to get an LH6 or LC9 block. Find some quallity pistons, upgrade to some Z06 parts, such as: valve train, oil pump, timig chain, cam, and heads. Thoughts?

The engine needs to have a broad TQ and HP curve, and hold up to sustained high RPM's.

Dave

[c5z28]

I didn't know they made aluminum 5.3's-free bump for you.