Different Pistons.

[RED LS1]

I'm trying figure out something here.

The Speed Pro/TRW pistons have a flat dished top and the Wiseco Pro Tru have the 2 valve reliefs in them. Are both of these a correct piston for our motors? Wouldn't the compression change somewhat between the 2? My cam is just a 212/212 Flat tappet right now and heads are champion Irons if that makes a difference.

 

[earlbrown]

compression will change based on total relief area and the compression height of the piston. Honestly I have no idea why some of those valve reliefs are they way they are. They aren't needed unless you're doing some sort of radical build.

 

[87GNSteve]

The Weisco TruPro I bought a few years ago were dished basically stock forged replacements. Is this something you seen with your own eyes or is it a generic photo from a Performance parts website?

 

[Ttype6]

I'm trying figure out something here.

The Speed Pro/TRW pistons have a flat dished top and the Wiseco Pro Tru have the 2 valve reliefs in them. Are both of these a correct piston for our motors? Wouldn't the compression change somewhat between the 2? My cam is just a 212/212 Flat tappet right now and heads are champion Irons if that makes a difference.

The pictures you're seeing don't represent the actual product. Both are dished.

 

[Lil Truck]

This is a Buick 3.8 Weisco ProTru I used, there are 2 comprssion heights available in their catalog.

 

[Ttype6]

This is a Buick 3.8 Weisco ProTru I used, there are 2 comprssion heights available in their catalog.View attachment 237840

One is for a 6.350" rod and stroker crank. I have a set for sale.