Is it cost effective to cut down pistons?

[69L48Z27]

I’m putting a BBC together and my piston to valve clearance was close at mock up but after assembled I was on the losing end, too tight.

I took it all back apart and my engine guy charged me a whopping $70 to cut the valve reliefs .050”. We also balanced the assembly prior. He said no rebalance needed if you take weight away.

 

[33 IMP]

Thanks John for your insight points well taken. I am going to buy new lighter pistons and not worry about how much metal would be left. Its not all that expensive for a set of 8. Reducing the reciprocating weight and all cnc matched is not such a little thing as well.

Agree! Buying the right pistons for the application is ALWAYS the right answer, if monetarily possible. I have a set of dished stroker pistons that will be over 400 grams lighter than what came out.

 

[oldkimmer]

I have had the old trw’s for big and small blocks done. We just took the dome off. It was solid. Definitely rebalance the assambly. I found an old retired guy with a laithe. He was more than happy to do them. Kim

 

[Kern Dog]

Squench is the new/old system now... Flat-tops and 'closed chamber' heads...
A squench system pushes the mixture towards the plug at TDC!

I think you are confusing Squish and Quench.

 

[gtx6970]

If your piston to wall clearance is good you should be able to mill those old ashtrays. It will require a rebalance though, just as changing to modern, lighter pistons will.
Done it once on a 426 Hemi when all you could buy was the old 12.5 high tops, worked great.

The engine in my car had 12.5s in it. Previous owner had them milled but the builder thinks it still in the 11.2 to 11.5 range ( motor was built almost 20 years ago )

I plan to open it up maybe next year and go thru it. dropping compression to a pump gas friendly 10 or 10.5 And I will be replacing pistons this time

 

[polyjohn]

When you 'squish' a hot mixture that has been lighted by a sparky plug, it has to be 'quenched'...

Totally 'SQUENCHED' is the past tense for 'squishing da mix'...

7000 times a minute, that's a lot of SQUENCHES...