Z/28 History Picture

[MikeSVX]

Originally Posted by RLHMARINES

I like what GM did for the 2000 SEMA 302 Camaro Concept. I wonder if the 5.3 block with a crank from the 4.8 or even one from the older LT1 based 4.3 V8 from the early 90's would work to make a modern LS based high revving 302.

Not what I'm looking for. If you google GM GenIII engines, it will give you Wiki with all the engine specs broken down for most generations. The gen III and IV specs are the same as far as bore and stroke. The 4.8 and 5.3 are the same engine just with different strokes. Basically if you put a 5.3 crank into a 4.8 block, you make a 5.3. Though I think the 4.8 are a little different and give you a bump in power over the factory 5.3. The only way to get the 3.00in stoke is with a custom crank. I'm looking around to see if I can find someone that would do it. The bore of the 4.8 and 5.3 is 3.78in. That means a lot of boring out. I don't thik you can go that far out. The 6.0L LS2/LQ4/LQ9 engines are the best bet. It already has the 4.00in bore and a stroke of . Thats a lot of displacement change going from 6.0 to a 5.0. I don't even know if the idea is possible. So far I'm sending emails out to shops and parts manufactures to figure out if it is even remotely possible to do it. The 4.8L would be the best option cost wise because they are a dime a dozen in the scrap yards, but I don't think they can be bored out to 4.00in. The 6.0 has the bore, but the stroke change is huge and even the truck version can cost duoble what the 4.8 costs. Destorking an LS2 would just be nutz considering the cost. Generation V engines aren't really an option because they all have a bore that is already more then 4.00in.

As for what would you get from a 4.3 with a 5.3 crank, thats just a matter of math.

(for V8s, found on Eagle rods website) Bore x Bore x Stroke X 6.2838

5.3L bore = 3.78
4.3 Stroke = 3.00

3.78 X 3.78 x 3.0 x 6.2838 = 269.35

If you want the 4.0 stroke form the modern LS you need to look at the 6.0L engines. However, you could built a full LT1 based 302, which is probably what they did with the Camaro you posted. The LT1 350 had a bore of 4.00in. The LS1 350 had a bore of 3.898in. Hmmm wonder if that could be bored out to 4.00?

[2cnd chance]

Originally Posted by MikeSVX

The american iron series in the NASA still restricts the displacement to 5.0L. Most of the Camaros in that series are running the old 305ci. You can update to newer engines as long as you meet displacement rules. The bore and stroke of the 302 was part of the reason that it was able to rev so high. I also think it would be cool from a heritage stand point to see what it would be like if the original Trans Am rules were applied today. It's just a what would happen senario.

The LS7 revs to 7,000 and has 427CI. What's not to love???

[MikeSVX]

The race series I want to run in is restricted to 5.0L and solid axles. All the Chevys are running the old 305ci engines. I just thought it would be an interesting project.