060 off top TRW pistons?

[vje55]

Guys, I need to skim 060 thou off the top of my old school TRW's, I believe it should be OK but after some thoughts?
They are currently out of the hole 060 and with my head CC it is to much compression.
BJ

 

[67 B-body]

I would think you'de be fine. People fly cut them for valve reliefs deeper than that!

 

[Cranky]

What pistons are they?

 

[Meep-Meep]

I'd measure some stock pistons and compare. Even cast out of anything should do since the forces are similar I'm thinking that a small area thin spot is not equal to the whole top of the piston being thin in terms of PSI. Force = pressure X area.

 

[Cranky]

I'd measure some stock pistons and compare. Even cast out of anything should do since the forces are similar I'm thinking that a small area thin spot is not equal to the whole top of the piston being thin in terms of PSI. Force = pressure X area.

TRW had a bad habit of just adding to the top of the piston for the correct compression height while not doing anything different to the bottom of the head. I ball end milled a good 200 grams from EACH piston on a set of TRW six pack pistons for a guy thinking they would be junk after hitting them with a 150 shot but they held up! I took out a lot more than .060" worth of shiny stuff...

 

[Meep-Meep]

TRW had a bad habit of just adding to the top of the piston for the correct compression height while not doing anything different to the bottom of the head. I ball end milled a good 200 grams from EACH piston on a set of TRW six pack pistons for a guy thinking they would be junk after hitting them with a 150 shot but they held up! I took out a lot more than .060" worth of shiny stuff...

Good to know! I have a set of the pop ups and I'm pretty sure there is a small pocket under the dome so I don't dare touch those.

 

[Cranky]

Good to know! I have a set of the pop ups and I'm pretty sure there is a small pocket under the dome so I don't dare touch those.

Yup, there will be a pocket under there but you can use a set of large spring calipers to get an idea how thick they are. Yeah, you will be sort of forcing the calipers out of them but they will take it. The larger calipers have plenty of give. If you have the L2295's, I can probably check some that I have laying around if you want to know how thick they are. Even taking out 100 grams would make a good difference in these old things lol

 

[Meep-Meep]

Yup, there will be a pocket under there but you can use a set of large spring calipers to get an idea how thick they are. Yeah, you will be sort of forcing the calipers out of them but they will take it. The larger calipers have plenty of give. If you have the L2295's, I can probably check some that I have laying around if you want to know how thick they are. Even taking out 100 grams would make a good difference in these old things lol

I think they are L2295's but I should look to make sure. I have at least one set that I plan to run with an old ISKY 1012B roller and will definitely need the squeeze. At some point if you can check and report the dome thickness that would be great. This project in line behind three others so no hurry!!!

 

[Cranky]

I know about projects that are in line lol I put it on the to do list....