Ok....few notes.
Are those pistons domed (positive dome volume sticking above the piston) or are they dished?
An 11cc dome is way too much compression for 60cc heads....even with a very large cam, it wouldn't work. An 11cc dish is not enough I don't think.
I would go with a Probe forged piston, model 10666-030. They have 4cc valve reliefs. This would give you a static compression ratio of around 10.3:1. They are probably $100 cheaper per set than the SRP's as well. I've used Probe pistons several times....high quality stuff. Plus the valve reliefs are deep enough to accept high lift cams...you won't need to have them cut.
Here's where it gets exciting: A Cobra is light enough to where you can err a little on the racy side...you could pick some parts that are a little wild for the street and it will still work.
However, having said that, torque is where it's at...and the key to a good streetable, fun car is a good broad torque curve that has very high average torque/hp numbers instead of just a high peak.
If I were building the engine, I would be torn between using the Victor Jr heads or the Performer RPM heads.
What happens is that with such a small displacement, the 210cc ports are gonna be a little big....so it will take some revs to get the air velocity moving. Going down to the Performer RPM head with say a 190-195cc port will keep the velocity up and give you more torque.
Either head will work, but the Vic Jr's will give up a little torque on the bottom end. Both heads have 60cc chambers, so that wouldn't matter.
Getting down to the nitty gritty, I would use the following:
Probe SRS 4.030" forged pistons, 4cc valve reliefs. These are flat top pistons, with just eyebrows for the valves.
Comp Cams hydraulic roller, 31-442-8, 224/224 duration, .533/.533 lift.
If you have the block square decked so that the pistons are at zero deck (flush with the deck of the block), use that cam, install it at 110/106, your static compression ratio is 10.3:1.....and your dynamic compression ratio is 8.05:1. That means that you could probably get away with running around 89-90 octane.
The piston quench with this combo would be around .039", which is a good tight quench.
The peak would be about 6000-6200, but you'd have significant torque all across the powerband....which is very important.
What's most important is that with that roller cam, you can turn the key for the first time and you won't have to worry about trying to make all the planets line up so you can break in the cam for 30 minutes....and then have to worry about whether it was done correctly. Just remember, if you assemble the rest of the motor yourself and you screw up a cam breakin, you're responsible for the carnage. And there WILL be carnage. Cam wipe outs will affect the whole engine....
oil pump, bearings, etc. It will be expensive.
Spiders (what holds the lifters in place) are around $50.....doesn't take but 30 minutes to install one.
BTW....the Performer RPM Air Gap would be the perfect match for this setup...
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