302 modification question

[Whistler]

what does a "302cid overbored .030" mean exactly and what are the benefits/pitfalls of such a modification?

 

[Broncobowsher]

It means that the cylinders have been enlarged from the standard 4.000" to 4.030" For performance it adds a couple of cubic inches displacment but not enough to notice.

It also means the engine has been rebuilt.
About the only downfall is that it is already bored once and if it needs rebuilding again, the cylinder walls may start getting too thin to bore it more.

It's nothing that will magicly add power or blow up. Almost standard pratice during a rebuild.

 

[bmc69]

It means that the diameter of the cylinder bores was increased (overbored) by .030" (from 4.00" to 4.03") It is only required when the stock cylinder walls have worn to the point that they are no longer tight enough to support/fit a stock piston. Replacement pistons can be purchased with .020", .030", .040" and .060" oversized diameters.

It's not a 'benefit/pitfalls' kind of thing..its simply a standard part of the procedure for rebuilding an engine, just like grinding the crank, or re-conditioning the rods.

 

[bmc69]

Once again I am shown to be the slowest typist on the planet...;D

 

[Whistler]

That is what I was looking for (both of you) thanks a ton.

 

[broncow72]

Once again I am shown to be the slowest typist on the planet...;D

Use both hands. ;D

 

[bmc69]

Use both hands. ;D

Am..one finger on each.;D

 

[broncow72]

Am..one finger on each.;D

Have you tried sticking your tounge out one side of your mouth? Works for me.

 

[wildbill]

Am..one finger on each.;D

;D ;D ;D Me also. Bill %) ;D

 

[Broncobowsher]

Randomly press a bunch of keys then go back and delete the letter that shouldn’t be there.