THUMPIN455

That is a very low budget for a complete rebuild. The problem with running the used pistons and not grinding the crank is longevity. If you are building for power then you want it to last more than a year of beating on it.

Have done them both ways, reuse the stock slugs, and bore hone and new pistons. Seems like the new pistons with a balanced assembly last the longest. If you dont care and you only want an engine to putt around with, then
#1. why bother with any performance change including a cam
#2 why care how much power it makes?

So you just hone the cylinders instead of finding out how much taper they have, on the Fords we did that too ALL of them, every single one was an oil burner after the "overhaul". But of course they were truck engines not some putt around stock mustang engine, they got worked.

If you are going for power, then do it right and do it once. If you want a beater engine, do it cheapest. Blowby is not a performance enhancing quality. I would rather spend my money once than three or four times in the lifetime of the engine that has new and reconditioned parts inside.

Sorry its just the aircraft/CNC machinist in me that knows the difference between .10 and .001...

P Zero

Im looking at the way racing engines are built. Racing engines have tolerances on the journals that would be considered out of spec on a street vehicle. And depending on the year of the motor, the pistons could very well be forged, so longevity shouldnt be an issue. Also measuring piston clearance and cylinder taper is important, but unless the cylinder walls are scored I wouldnt worry about it too much. Also, most people dont have bore guages, dial indicators or feeler guages, micrometers, etc. So my belief is that they just get it bored because they dont really know if it needs it or not.
From my personal experience, MOST engines do NOT need to be bored out. I put 70,000 hard miles on a 302 that was rebuilt the "cheap" way (re-ring,re-bearing), there was no smoke whatsoever and still doesnt smoke to this day. The only one Ive ever had smoke is when the valve stem seals hardened up, and then it only smoked on startup. Replaced em no more smoke.
Now if I was building an all out bad *** motor, yes Id do it the "right" way, but then again the block, crank, rods and pistons alone would easily cost more than double.
But really it all depends on how you run your motor. If its a drag/street motor you dont need the loose tolerances, but on something that will see sustained higher rpms you want the tolerances loose otherwise itll lock up. Aside from that even if the tolerances are a little looser you can just run a thicker oil and have no problems, and the benefit of good high heat lubrication.
-P.

my77stang

if you can catch your fingernail on the ridge at the top of the cylinder, it needs to be bored. thats always a good redneck rule of thumb.