okay so i need help

[kego]

so while trying to sell my TGP motor I discovered it had sealed power pistons. okay fir enough. I did some digging and after I couldn't find a number for Federal-Mogul I called jegs. jegs sells sealed power. they didn't have a piston that fir the 3.1 N/A or turbo. so they gave me Federal-Mogul's "hush hush" number which I will post at the end of this (bastards). so I called federal and they told me they don't currently nor have they ever had a 3.1 piston. they do have them for the 3400, which would verify my for sale claim that this motor is bored .030 over. now I have a new problem. I asked them what that 3400 piston is made of. he told me it was cast AL. I don't think I'd trust cast AL in a turbo app. am I correct in my claim that a 3.1 bored .030 ~3.4L? or could these pistons be something else?

[robertisaar]

http://60degreev6.com/content.php/101-CR-Calc

.030 with a 3100 is 3.534" bore, which comes out to 3188cc.... rounds up to a 3.2, certainly not a 3.4 though.

a 3400 has a bore of 3.622"...... to get a 3100 up to that, you would need to go .118 over, which is a huge overbore, something that probably shouldn't be attempted or at least would require sleeves in the block and other tricks to keep some kind of cylinder wall thickness.

[Guest]

FM definitely did make 3.1 pistons, they are what I used in my 3.2L hybrid (.030" over 3.1), about 13 years ago. They were cast pistons that saw abuse with up to 9 PSIG of boost at the time, if I had larger injectors and tuning ability back then I would have ran more boost. Cast pistons are not a problem with a good tune and boost.

[robertisaar]

also: rockauto shows sealed power pistons for a 3.1.....

H562P
H561P

both of those are cast

H561CP
WH561CP

both of those are hypers.

they're intended for the N/A versions though. i can't say that i've ever seen any marked specifically for the TGP engines.

[kego]

okay 3400 sounded fishy tome but i thought that i have heard that before but that would eliminate the need for a 3400. that's what was weird to me. so it makes a 3.2 i have been put on notice.okay so these pistons have been ran with boost. then why would one choose manley over sealed power? sealed is dirt cheap and they offer so many types.

[kego]

i couldnt see the AL pistons being a problem any more that the AL heads the 60 degrees all use. so what makes the sealed power a worse choice than any other piston of similar chemical make up?