When I first tore it down there were no overbore markings on the pistons so I assumed it was standard and a 292. I checked the cylinder bore above the ring grooves in the block as a 0.40 over 272 and it has alot of cylinder wear. I think I'll go with the 292 block that I have with the ECZ-G heads.No sense using the -C heads. What cam would you guys suggest? I have a cam with 249 deg. at 0.50 and .500 lift at the valve with T-bird rockers sitting on the bench but it's just way too much duration in my opinion,especially since I have a cruise-o-matic behind it and a 3500lb Vicky with the 3.31 rear end.

At a 3.665” bore, the cylinder is 0.040” over the standard size.  Standard bore size for a 272 is 3.625”.  You’ve could have a 0.030” over 272 with 0.010” of wear or could be a true 0.040” over if you are measuring the cylinder at the very top where the top ring doesn’t ride.   Don’t be misled by not finding overbore sizes on the piston tops as not all pistons are stamped with bore sizes.  And some pistons have their bore sizes stamped with ink if labeled at all and that identifier disappears once the engine has been run. Measuring the bore lower down in the cylinders may give you a more accurate determination of what bore size you’re currently dealing with.

 

Sonic testing of the block is always recommended when in doubt.  Although most 272's will bore out to a 292 bore size, there's not much left after that point for any additional boring.  Sonic testing will tell you exactly what is remaining in the block and where any core shift resides.

Lorena, Texas (South of Waco)

I believe 272 pistons are getting a little scarce, but your 272 will safely bore to 292 size, 292 pistons are common.

John - "The Hoosier Hurricane"

the 292 block is standard bore right now,I'll probably just get that block and crank over to the machine shop and get them checked out. the crank in the ECG block is .10 under on the mains and rods so I'll just use the best of what i have and use the ECZ-G heads. I also have a set of ECZ-C heads as well. all three engines that I have need complete rebuilds so I'm expectimg the cost. Going back into my '54 vicky with a fenton triple deuce manifold, T-Bird exhaust maifolds,and whatever other goodies I can get a hold of.Kind of a clean slate right now. I also have a Muculloch supercharger that i got from an 80 year old friend of mine....don't really know what to do other than I reeeeaaallly want to drive my 'ol girl again!

I think what you may have there is a .040 over 272. If it needs a complete redo including another rebore, then the 292 may be a better bet. If it doesn't need a complete redo & the 292 does, it's your call. It depends on the situation, time & $$$ wise.. In case your not familiar, the crank assemblies are the same..

Paul

I just aquired what I thought was a 58 292 with ECZ-G heads. well the heads are good ECZ-Gs but the block bore measures about 3.665" which should be a tired 272 bore. the casting nubers are as follows...pass. side of block-ECG60150 (or the 0 is possibly a C) , dist.area- 26 ECG Dif , main caps- EBU-6328-B . should this be a 272? and how far can I safely bore this block. I also have a late 292 block in the garage as well,should I just use the late block instead? thanks for the help!