Budget 302 Build

Honestly, The engine came out of my car and is sitting on the stand.....I got some rebuilt heads that have new seats and guides for 30 bucks and cut my teeth on porting, and so I tinker on.....it is like playing with toys for a guy with some time and limited cash. The purpose is probably "for the fun of it." Maybe not noble, but mostly truthful.....and as always, it stretches my brain.

 

Well, the budget 302 hit a snag. I didnt inspect it well enough from the start. It was a running motor with compression within 10% high to low, so I mistakenly thought it was decent. There is a small cavity that looks like tooth decay, near the top of #6. About 3/8" across and about .050 deep....looks to me like an imperfection in the cast iron. I will post up a pic. Maybe a small enough flaw to ignore since it ran with it, but even with my sort of low standards, I dont like it and may be shopping for another block. The 289 rods will get stashed unless I find another freak. I did get a 60 buck ridge reamer from NAPA and after the first 3 holes, I actually figured out how to use it quite precisely. The 1-2-3 cam for the cutter is really just an on-off switch; I dont know why they number it. Secondly, centering in the bore is a bit fussy, but can be done by leaving it slightly loose and lightly pushing it away from the cylinder edge it drags on to get it into a position where it drags the same all the way around. The cutter must start below the ridge, and when it is centered and snug, turn the cam from 2 to 3 (off to on) and rotate it out of the hole. I coated the ridge with trans fluid first. Worked nicely after learning curve.

 

Taller decks and dished pistons.

 

I don't think the deck height changed. Either dished pistons or slightly larger cylinder head combustion chambers is likely what dropped compression ratio...

 

302, 68-72 8.206 deck height. 73-76 increased to 8.229 deck height. That .023" deck height = about 10CC loss of comp area. On a small engine like the 302, that's a lot. On a 523 BBF stroker, no big deal. They did the same to the 351W & 460 blocks to lower comp.Why do you think everyone says to get an early block for the lower deck height?

 

I always thought the blocks were the same from '68-'76. That's interesting.
I have a '68 block in my Maverick right now, so I guess that's a good thing. I never had it zero-decked...