The car needs more power. Compression check came back low, but a leakdown test showed that at absolute worst case it was leaking down 8% through room-temp rings. So most of the compression issues are valve/chain related. So to keep the car running and more competitive I think it's time to go through the heads this winter. The car is purely used for autocross so it only needs to get from 30mph to 75mph as quickly as possible. I don't want to lose any power over the current setup under 3500rpm or so, and would like to gain from there up. Rev limiter will be set at 7200rpm just to avoid ever having to shift (I spin the stock cam to 6800 now), but the 3500-6500rpm range is more important for power. The current low end torque (325 by 2200) works great down low and I honestly wouldn't want more as it would be more difficult to drive off the corners. But I don't want to lose any in the 2500-3000 range either. Will obviously be getting a custom cam done at the same time.

Current specs:
98 LS1
102mm lid/MAF/TB
Mamo ported FAST 102
1 3/4" ARH headers into a 4" single
10% ATI damper
Crank scraper, pan baffle, high pressure pump, catch can
7.25" twin disk
M29 trans, 3.42 rear
3180lb race weight

Initially I was looking at grabbing some 243/799 heads to send to AI, but it seems like the TFS220s may be a better option than that. Is there anything else that I'm missing in that price range?

Video for reference

 

I would try these out. Cheaper than cnc ported heads and the TFS heads.

 

I know I had talked with Tony about running his AFR 205? if I were to build the theoretical 5.1 build, but I would need to pull another 300lbs out of the car without ruining the weight distribution to make that engine worth it. That same head would probably still work well on the 5.7 so I should probably at least ping him again to see what the ballpark cost would be without the requirement to spin to 8500. Then if I get the car light enough I would be able to re-use some parts.

 

How much power do you want to make? Are you willing to change rearend gears?

 

There is no point in changing gears right now since I'm not willing to spend money on a valvetrain that will be reliable north of 7500rpm. And I'm trying make as much power as I can while staying in a similar price range of AI ported 243s. I'm not willing to spend an extra $1000 over that if it only gains 20hp.