how should I proceed here?

[Grumpy]

Hello! This might be kind of a rambling post. I've been out in the garage all day during this snowstorm and now I'm kind of at a crossroads.

I'm doing a refresh/cleanup on the 327 (331) that has been living in my '60. It has low miles, maybe around 10,000 since it was rebuilt last. I'm mainly just checking everything over for piece of mind since I am not the one who did the work to it.

I just pulled the heads today, and after cleaning up the deck surface and a couple of the pistons measured for deck clearance. I suspected previously that they may be a little too far in the hole based on a measurement I had taken earlier last summer with a piece of solder down a spark plug hole. My suspicion was correct, and they are indeed .050ish down the bore, with up to .005 variation between the four that I measured (highest being .054). The gasket that was in there was .048 thick, which makes for a whole tenth of an inch for quench distance and a lowly 8.5:1 compression with the flattops in there (guessing 5cc valve relief just eyeballing). I suppose with that low of compression quench isn't really much of a concern anyways.

My initial plan, before I tore into it, was to just use some .015 shim gaskets, and throw a different cam in there and have one more summer of use before I rebuild another 327 I have. Now I'm wondering if I should spend the money now on new pistons and rebuild this one "right" or if I should just run it as-is for the summer and stick to my original plan... It did run fine before, but could have had a little more oomf for my liking.

The other engine I have is another 327, but it's already .040 over and had a bad rod knock. If the crank looked ok I was going to get new rods and some pop ups and build a "365hp" out of it.

Thanks for any input! Sorry again if I'm rambling, I'm still trying to thaw my brain out from being out in the unheated garage LOL

I think the pistons that are in there currently are the rebuilder type with a compression height of around 1.655" instead of the stock 1.675". I would almost bet on ithe. So hopefully a new set of "regular" .030 pistons would fix it. It is an extra $300 I wasn't planning on spending this winter, though.

I have decided to just go ahead and get new pistons now after weighing all my options. I even contemplated running a ball hone through the rusty 365hp in my garage and running it as-is with just new gaskets LOL (it belongs to my landlord, but it's available for use if I wanted to put the work in)! But even doing that, if it didn't work out, would cost as much as pistons for my good block.

I have found a couple good deals, and my choice is between:

H660CP -flat top, hyper, 2 relief

L2165F -flat top, forged, 4 relief

I'm a little hesitant with using the hyper-eutectic pistons in this block without have a machine shop really check the bore measurements good (I don't have the tools to do so at home). Would this possibly be an issue with the tight PTW clearance they are sized for? The forged ones would seem to be more forgiving, at least in my head...

from what youve stated
Id just go with the thin shim head gaskets until your willing too pull and go through the engine re-fresh,
with new pistons, rings bearing cam and lifters ,
if your going the engine re-fresh route obviously theres other concerns, and having the block cleaned,carefully inspected, painted , and the oil passages carefully cleaned out, new freeze plugs and cam bearings installed is a good start.
its always a good idea to accurately measure the pistons and block bore size and if you don,t have the required tools visit a machine shop,
that does as the cost is generally worth the problems that can be avoided by doing so,

forged pistons are rather nice, but hyper-eutectic will function just fine if the rpms are generally under about 6000 rpm ,
and you stay out of detonation, which will kill any piston,
but forged has a bit more tolerance to heat and abuse so they are slightly more forgiving,
be sure to look up and measure and use the correct bore to piston clearance

read these threads (and try to read the sub links)

the more knowledge you have the fewer issues youll tend to get yourself into,
or screw up, yeah most of us learn by screwing up, myself included,
the secret is in learning from your own and other peoples mistakes and not repeating either.

yes theres no doubt that the links and sub-links require a good deal of effort to read..
that effort will also save you a great deal of wasted cash and prevent making expensive mistakes.
a day or so spent reading links will help avoid many potential problems

http://garage.grumpysperformance.com/index.php?threads/block-prep.125/

http://garage.grumpysperformance.co...k-after-a-cam-lobe-rod-or-bearings-fail.2919/

http://garage.grumpysperformance.com/index.php?threads/cam-bearing-install-tools-install-info.1479/

http://garage.grumpysperformance.com/index.php?threads/grinding-block-for-stroker-assembly.2855/

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.co...g-and-installing-connecting-rods-pistons.247/

http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/#post-81042

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.com/index.php?threads/piston-related-info.110/

http://garage.grumpysperformance.co...ng-and-basic-piston-ring-info-youll-need.509/

http://garage.grumpysperformance.co...y-in-building-a-good-engine.11682/#post-54682

http://garage.grumpysperformance.com/index.php?threads/piston-coating-deburring.4516/

http://garage.grumpysperformance.co...piston-to-bore-clearance-on-your-block.14251/

http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/page-2#post-75256

http://garage.grumpysperformance.co...block-cylinder-wall-thickness.976/#post-22976

http://garage.grumpysperformance.com/index.php?threads/bare-minimum-tools.11026/#post-48785