Yes you will need a stiffer clutch spring or variable pressure plate (centrifugal) of some kind.

As for the heads...... Really depends on your budget. I would opt for a good exhaust upgrade before doing the heads. The engine is basiclly an air pump. If you remove the restrictions on both intake and exhaust then it will react to changes in between better. Keep the stock exhaust and any other change benefits will be reduced.

And then when you do the heads you would need cams that would react to the bump in compression.

And to see the full potiential of your changes you will need a programmer of some sort. The options are many. You need to consult who you are planning to use to do your dyno tune or if you want to use auto tune then read up on the procedure to do so and decide if you are capable of that. Then choose your tuning device.

 

If you mill the heads to 82cc chambers you can get to about 10.5 CR with .027-.030 HG, use some cams with a 42* intake close, Woods 777 or something similar & you should be in the 105-110 HP range. If your clutch is in good shape you should be good with a SE or Barnett HD spring. A decatted header will work OK & you can always add a better pipe later, but if you can swing it now it would avoid having to retune it later with the change. Just find someone that knows what they are doing & can give you some proof of results from previous builds.

 

You need some lower gearing:
Baker DD7
Evo-Industries 49 tooth clutch basket
30 tooth pulley & belt
An andrews48 with mild headwork and a gearing change would makrE a quick and dependable build.

 

This:

 

Sent you PM..

 

That!
I'm making 113hp with stock pistons, mild 54 cams and stage 1 heads. Ya can go over 10.5 with stock Pistons. No need for lower gears, fancy 7 speed or clutch. SE spring is holding fine and I could use another gear cruising at 80+... Don't even mess with the stock header, get a proper 2-1-2 or 2-1. Proper combo and tune is the key.

 

So WHAT did you decide?

 

How much do you have to take off the heads to get 10.5 out of stock Pistons with .030 head gasket??

 

Too much. I think if you take more than .040 with a .030 gasket you might have intake alignment issues. Depending on cam lift, you'll need to check piston/valve clearance