I have a chance to get a freshly bored 1973 454 block. It is a 4-bolt main so it's what I really want. This is the later casting that can take up to a .125 overbore. It has already been bored .060 but is freshly bored and ready to go. I had another buddy tell me he wouldn't want to use a block that was bored more than .030 regardless of what kind of block it is.

I recall having to bore my 400sb .040 to get it to clean up and at first it ran hot but now does fine since I got a much bigger radiator.

Anyway, any thoughts on taking such a block .060 over? The bore work was also done by my favorite machine shop so I know it was done right.

TIA

I was going to go .060 over on my stock bore 454, only reason i didn't was the extra cost

-Ryan

Originally posted by Rich-L79:
I have a chance to get a freshly bored 1973 454 block. It is a 4-bolt main so it's what I really want. This is the later casting that can take up to a .125 overbore. It has already been bored .060 but is freshly bored and ready to go. I had another buddy tell me he wouldn't want to use a block that was bored more than .030 regardless of what kind of block it is.

I recall having to bore my 400sb .040 to get it to clean up and at first it ran hot but now does fine since I got a much bigger radiator.

Anyway, any thoughts on taking such a block .060 over? The bore work was also done by my favorite machine shop so I know it was done right.

TIA Well, a small block can easily go .060 over and thats where they like to stop. I have always heard that you can safely go .100 over on a Big block. If all else fails, have it sonic checked.

I wouldn't worry about .060 at all. Like has been said, BBC can go .100 easy. Mine is at .070 and gets raced every weekend, no problems. ;)

I would have the cylinder block walls sonic tested,if the wall is .250 or more your ok graemlins/thumbsup.gif

Rich, my 427 is .060 and have no problems at all. My next re-build I will be punching it .070.

I would get it and build it.

I just punched one .100...
I've done a 402 to .125 using STD 427 pistons.
.060 is nothing on a BBC.
Ask the fool who told you that if they've ever actually looked at how little .020 is, because that's all your taking off the thickness of the wall from .060-.100.
Or .015 from a .030 to a .060 overbore.

My 427 is .060 over. Not run yet,i just got the crank and cam in last night. Pistons and rods go in tomarrow.

Danie

.060 shouldn't be a problem .... but... sonic test it anyway ... with core shift & production tolerance's .. or should I say lack of... I'd say play it safe & sonic the block.. its clear bored & apart .. it don't get any easier then now ...peace of mind for when you're puting the hammer down :D

My '71 CE 2 bolt 454 block "289" casting was sonic checked too and it can be bored to .125 if needed. Since it is currently standard bore, I see little need to go over 0.030" since it will clean up with that much.

The only downside I see from doing 0.030" instead of 0.060" is I will have a 489cid stroker, not a 496cid stroker. :( ;)

smile.gif

Rich, Has the final hone been done yet? If not I would suggest getting the pistons first so your machine guy has a number to hone to. Verify the overbore yourself. The block your using will be fine with a .060 cut.

Mark

Originally posted by Mark 502:
Rich, Has the final hone been done yet? If not I would suggest getting the pistons first so your machine guy has a number to hone to. Verify the overbore yourself. The block your using will be fine with a .060 cut.

Mark It looks like the honing has been done already. It's going back to the machine shop soon for a full evaluation and measurements. I found a few slight vertical scores in three of the bores I want checked out. One is too low to affect the rings, one is only visible and not enough to even catch a fingernail and the third one is very slight and may or may not be in ring rubbing territory. It's been on a shelf for 6-7 years so it really needs to checked over by an expert.

As long as the bore size can be honed again to match the skirt clearance and finish requriements of your chosen pistons, you'll have no issue. Took my 72 454 to .060, and the only thing I noticed was that it ran a bit warmer than the last iteration. BUT, all internal clearances were tightened up, and we ditched the HV oil pump, if that matters at all.

You need to get them to take the bore guage and measure the bores for size and accuracy, is all.

be running a 440 like me. Nice mill!