Brain Trust Needed - 2L Refresh Options

[yeahmag]

This might be long...

My current combo runs great, but I've been sitting on a set of Finch heads from Len Hoffman for years. There is no racing right now, so it seems like a good time. Here is the current combo:

2056cc
Stock Rods
Stock 2L heads (match ported)
86a Cam
9.5:1

I got a set of JE pistons in another deal (brand new, 96mm) and they appear to be stroker pistons. By my calculations I'd only need a 5.294" rod to counter the reduced pin height and am planning on a 5.325" rod or longer. Should be good either way there.

Now for the big problem. The Finch heads have a 50cc step-cut chamber. I like to run a tight deck (.04") and that combo would put me at 10:1. To get to the 9.5:1 I've been running I'd need to run almost .06" deck height.

So three questions.

1. Can the 86a handle 10:1 on 91 pump gas with proper tuning?
2. Is it better to run a loose deck and keep it at 9.5:1?
3. Put a 2cc (or larger) dish in the piston tops to keep a tight deck and lower the CR to 9.5:1 which I know works?

Thanks!

-Aaron

[larryM]

10:1 on 91 gas is a daydream - some get away with it on iron engines, but no way is is "safe" on alu engines

you can buy a MSD or other gadget to dial back the timing, but doing so simply results in no better performance than y'd get by sticking with your current CR


. . . if it's just a race car - go for the max, understanding that you will frequently rebuild the motor in your quest for the trophy - that's how "real racers" look at it - $$$ & longevity are irrelevant