RideZX-6R

iTrader: (8)

Hey all,

Planning on doing heads/cam after finding a few good deals and deciding that while a blower is awesome, I don't need to spend so much money nor will I really want all the torque/wheelspin on HPDE days.

I'm going to run a spin monster cam (230/234) for drivability. And I'm getting a set of ported LS3 heads with oversized valves, etc. It's my option how much to mill them down. I'd like to run a thinner HG (thinking .040) and mill the heads as well to get decent compression out of it.

What amount of milling would you guys recommend? It can be on the aggressive side as PTV clearance shouldn't be an issue with the spin monster cam. I will run a 50/50 mix of 92 and E85 at minimum - might do straight E85 but I'd like to know what should be safe for 50/50... Recommendations for both would be great. (Power predictions would be cool too if you want to speculate)

Thanks all!

cr250r

iTrader: (4)

12.1 maybe more

CAMSTER

iTrader: (10)

I'm working on same project rite now, if you are not changing pistons and using your LS3 heads there's limited amount of compression to be had, BUT you can get close to 12 to 1 assuming your base compression is 10.7

Here's what you can do; mill heads 0.050 and use 0.045 head gasket just to be on the safe side, some use 0.040 but is cutting it close.

You need to check for piston to valve clearance and may have to fly cut the pistons but is worth it.

jerrytx

I don't think you'll get over 11.2 compression, no need for greater than 93 octane. Ported LS3 heads (if they lay the bump down in the chamber) will be 60cc (decked .045), if they remove the bump, 62cc.. (also .040 - .045). Most shops won't deck them more than that due to concerns over strength. Definetly go with cometic .040 gaskets to regain some compression, and dont be afraid to flycut the pistons. I've built two and neither one was over 11.2:1. I think you need custom pistons to get close to 12.0:1 with ported LS3 heads.