Edelbrock ALuminum 6089 heads, 71 350 block...

here is my question, the shop I had to my heads sold me the FP-1010 gaskets, they're listed on summit as being 4.166" bore, the gaskets i took off are stated on summit as being 4.125"

does this make a difference? am I going to royally screw something up by running the 1010's?

the FP1010's are 8.9 compressed volume, the FEL-7733PT2 are 8.7 compressed volume, this make a difference either?


thanks fellas.

You are fine. I suppose your enfine may be stock bore or .30 to .60 over, so your cylinder bore is 4.00 to 4.60. Both gaskets are slightly bigger and will work fine. I have a 4.30 bore on my 355. I had the standard 4.166 fel-pros, but just changed to a 4.65 bore cometics MLS gasket. Supposedly it is best get the gasket bore closer to actial cylinder bore as long as the gasket doesn't protrude into the bore. However, both of the gaskets you mention are in the commonly used acceptable range.

awesome, thanks dude yes, i forgot to mention that the cylinders are stamped 0.030, i think pdq or jim told me that means my cylinder has been bored out 0.030


thanks again!! didn't know if it mattered whether the gasket was right on or what

They're right... if the pistons are marked .030, then the cylinders have been bored .030" over factory bore size. That makes the cylinders 4.030". Both those gaskets have larger bore sizes than that.

I don't know how much the .2cc compressed size (or .04" bore difference) matters between the two gaskets when the heads are installed, but the larger bore FP1010's will increase the combustion chamber size over the FEL-7733PT2's.
The FEL-7733PT2 gaskets are .040" or .038" compressed I believe. What thickness are the FP1010's?

It sounds to me like it'd give the engine a tiny bit more compression using the stock replacement FEL-7733PT2 gaskets. I could be way off base here.

I'm using the 1010's on a 355 with aluminum heads because they have a flattened copper fire ring to avoid brinelling the aluminum.

Although even the gasket bore size effects head volume, the change in compression would be tiny for the gaskets mentioned here.

On my engine I went from a 4.166 bore gasket to a 4.065 gasket bore. My compression went from 7.6:1 to 7.66:1.

The bore size change you are talking about here is even smaller so you might see a few hundredths (.02) change in compression...no big change at all.

Thanks.... I was just curious as to how much changes in gaskets REALLY affects compression. It's such a tough thing to get a grip on sometimes.

Everything stated here is right on. Just one thing to add, the compressed thickness of the 1010 is .039". I have a 350 bored .040 over and the 1010 changed my compression less than 1/10 of a point from the standard fel-pro gasket.