Piston question

[85boostbox]

Anyone hav ea picture of a TRW forged piston for a 2.5. I got this motor out of a junkyard and have torn it all down and the pistons are smooth and really shiny. No names on them. THye are 1mm over and this motor was ran real lean with no piston damage. Makes me wonder what kind they are is all.

---------- Post added at 09:24 PM ---------- Previous post was at 09:22 PM ----------

Pretty much I cannot figure out what pistons I have in this motor. But they are made in the USA which is the only stamp I have on them.

[zin]

The surest way to determine if a piston is a forging or not is to look at the underside of the pin bosses. If they are undercut (a hollow between the dome and the boss), then they cannot be forged, and rather are a casting.

In the forging process, a hydraulic ram slams into the slug (just below the melting point) and forces the metal into the basic piston shape, but if it had an undercut, the ram couldn't be withdrawn. This is also one of the reasons why some "TRW" style forgings are heavier than their cast counterparts...

Mike

[GLHS60]

I don't think TRW ever made any 2.5 forged pistons. I have some flat top forged 2.2 TRW's, don't think they even made any turbo forged pistons. Post some pics.

Thanks
Randy




Anyone hav ea picture of a TRW forged piston for a 2.5. I got this motor out of a junkyard and have torn it all down and the pistons are smooth and really shiny. No names on them. THye are 1mm over and this motor was ran real lean with no piston damage. Makes me wonder what kind they are is all.

---------- Post added at 09:24 PM ---------- Previous post was at 09:22 PM ----------

Pretty much I cannot figure out what pistons I have in this motor. But they are made in the USA which is the only stamp I have on them.

[Directconnection]

TRW's are forged with the TRW on the inside (backside of the dome/top of piston)

[85boostbox]

Ill get some pics up of them later. As stated the only marking I can see without taking them out is usa. There is another marking that I think says AH or something along those lines. As stated will get pics up later.

Paul