I'm actually going with the factory 3cc dish style pistons, mod max sells the ones I am buying, they are a 3cc dish speed pro and with those pistons on any stock 4v and un-milled heads it shows a compression rating of 10.2:1
that number is incomplete. B heads and 99 01 heads have a bigger combustion chamber than 03 04 heads.
this is why the mach 1 had a higher comp ratio than the earlier cars. ~2 cc smaller chamber.
flat tops in the 03 04 cars yields about 10.5.
in the earlier cars its like 10.1 10.2.
dish with the early heads is 9.85.
depends on how much you mill, but you can bring that number back up.
you may also need to mill the timing cover as well. be sure to check.
I want to get the cams degreed as I know this makes a big difference but I won't be getting the adjustable cam gears to really do it right so I will just be having them installed un-degreed. This is fine with me though, I've seen 03-04 Mach 1s w/ C heads pick up 20 rwhp from 96-98 cobra intake cams UN-Degreed. So I am hopeful.
mach 1s were undercammed imo, they should have used the cobra cams from factory.
even the small jump in duration with the late c heads helps them noticeably.
you will leave some torque on the table if you don't advance the intake cams. advancing them works nicely because you can add the torque down low without seeing too much of a hp penalty because you run out of intake up top anyway.
plus the car is heavy anyway.
My engine builder showed me multiple other 2v and 4v motors that had the same piston slap issues mine has, seems to be a very common issue that I would most definitely look in to if any of you other guys plan on rebuilding your engines too.
pretty sure mine has some piston noise as well. motor has at least 220k miles. many of them tuned, geared, etc.
also. will you use the FRPP 4v pump or the 3v/gt500 pump?
