Bored .30 440

[69Charger_440]

If a 440 has been bored at .30, is there still room to play with in the future or is it at its end?  It's a '69 block, I believe.

Fernando

[TylerCharger69]

I've heard of people going .060 over with no trouble.   Then I've heard of others  say they developed overheating problems  boring that large.   That would have to be your decision to make.

[69Charger_440]

Forgive my naiveness on this subject, as I am still learning   , but once you are at .60, is the engine still usable or what could you do, if anything, to keep it for future use?   

Fernando

[firefighter3931]

Usually going .060 on a stock block is no problem. On a performance type build it doesn't hurt to have the block sonic checked to see what's there in terms of cylinder wall thickness. A block that has gone .060 over can still be saved but it's expensive. It involves sleeving all the bores but then you'll have a perfectly good block to start over with. If it's a numbers matching engine it might be worth the cost and effort assuming you want to keep the whole package together.

Ron

[69Charger_440]

Thanks for your advice, guys. 

Fernando

[TylerCharger69]

.060  is the limit, I would say.   As far as salvaging the block after that,  it isn't a problem because you can always re-sleeve.   In fact, a lot of people who are anal retentive about factory specs re-sleeve their blocks in restorations, bringing them back to standard factory size.   I remember having to price a set of Hemi spark plug wires for a customer  and they were over $500.00  for the correct date coded ones.  That's just an example of the extreme people go to who go to car shows for high point scoring cars as far as factory correctness is concerned.

[Wakko]

My 440 is .030 over and it was great...never any overheating problems.  Next step would be .040 and then .060, but I wouldn't try anything over that, as already stated.  Do they even MAKE pistons over .060?

[Chryco Psycho]

have the block sonic tested
I have seen blocks that were too thin when they left the factory with a stock bore & I have seen blocks that could have been bored .100 & still had twice as much as the minimum wall thickness left 

[Wakko]

Wow...that's scary.  What's the reason for such inconsistent castings?

[RD]

Do they even MAKE pistons over .060?

they do, but they are made mainly for the siamese blocks

[skibuff]

I have been told, but I can not verify, that the "newer blocks" made from 1976 through 1978 can safely be bored to .060 over without heating problems.  The blocks before that apparently have less tolerance to boring and may have heating issues if bored to .060.  However, my 440 has been bored .030 over and has no problems whatsoever.

Skibuff