I pulled 72 350 in and had planned on gaskets/cleaning and re-install.... and then.... one burnt valve and now there is a valve job. So I have a good running short block (90k miles) and heads headed to the machine shop. So here is my conundrum. Do I source the steel shim gaskets or machine the heads to offset the fel-pro gaskets? And if I do that should I just have them mill a bit more off to increase the CR? By my math .030 more will get me 9.0ish to 1.

or...

Should I go after high compression pistons/bearings/bottom end machining?

I'm really going after a reliable cruiser, hoping to end with TH350 w/ shift kit, 3.23 posi, nice q-jet, headers, pretty basic setup..

Suggestions?

Thanks
Tim

 

If you're going to go with new pistons, IMO it's better to just do a whole proper rebuild at that point. There are Olds vendors who should be able to get you thin head gaskets if you go that route. Shaving .030 off your heads with thin gaskets isn't going to get you to 9:1. Stock the engine is only 8:1 true CR according to those who have actually measured/calculated everything.

 

That motor should have had the thin gaskets on it to begin with so that's a wash. Smitty at M&J has the same gaskets if you like.
From there you'll need to cut about .060 off the heads to make any real difference. That should put you in or around the 9.0:1. Then you can consider other mods, cam, intake etc.
However I'd seriously consider an exhaust upgrade and gear change as well. Each of those can make a sizable difference in performance.

Best of luck!!

 

Everything is on the table at this point, I have a setup with headers and a nice 2 1/2" H pipe exhaust setup. Gears are definitely going to get upgraded along with posi, but that is down the road.

I guess my thought is since the heads are in the the shop already and they are going to mill the base flat, it shouldn't really cost much more to have them take off a bit more. The thin head gaskets are quite a bit more expensive so going with felpro and milling seems to make sense.

I know the heads aren't the best spot to gain compression, but I'm just trying to build around what I have..am I crazy for building around that short block? Should I just bite the bullet and dig in?

Thanks
Tim

 

Bite the Bullet!!!!! Life is short - go all the way the first time

 

By my math, with those big dish pistons down .020 (a guess), a .040 gasket, and the heads shaved to get a 60cc chamber, Cr is at 8.5. With the intake fitment issues I don't think milling the heads is worth the gain. There just is no getting around those big dishes in the pistons.

 

I'm with Captjim. Those pistons suck.

By the time you pay 150 bucks to mill the heck out of your heads, then find out you have to mill and ruin an intake for another 150, you might as well just get better pistons.

 

yes, and yes.

 

It seems a consensus has been found on the internet...didn't know that could happen. In hind site I guess it makes sense, its out, its apart, and there is no reason (other than money but hey you can't take it with you) to not just build what should be in there...I guess its time to tear it apart!

Thanks
Tim