Dynamic Compression Ratio using 93 octane on AFR Aluminum heads

[piss&vinegar]

Hi,
I am building a 383 for my S10 and I am in the process of calculating what I need for my dynamic compression. I have read where 8.5 is right on the edge for Iron Heads at 93 octane but I have seen where people report that you can go 0.5 higher with Aluminum Heads based upon the cooling affect of the material. Got any opinions/suggestions?
Thanks,
DC

 

[OW99]

What is it going to be used for?

 

[vadorsnake04]

Why is this in terminator engine/tuning? Is this is a terminator engine?

 

[piss&vinegar]

This is going to be a tow rig. It is this section as I thought people may have experience as the question is generic to any engine.

 

[Quick Strike]

I think I would stay around 8:1 dynamic compression in that application and focus on a good quench, reducing hot spots (sharp edges) and improving air flow in and out. That way you are not on the edge of detonation all the time and could deal with the occasional tank of bad (lower octane) fuel. It should still be very responsive thay way on 93 octane depending on the cam parameters you pick.

 

[piss&vinegar]

Thanks. I have my quench at 0.038(combination of deck height and head gasket). I am using dynosim5 and pat Kelley's dynamic compression calculator to help in this process.

 

[OW99]

7.5-8.5 is a good range for good pump gas. Since this is a tow rig you may want to go for the lower end of this range if you get stuck in a situation where you need to run 87 octane. Plus the intake valve closing point should be relatively early so take this into consideration also. I wouldn't go over 8.0 with iron heads.

 

[Quick Strike]

Just remember to use advertised duration in Pat Kelley's calculator.