4.1 Questions

[RSTTYPE85]

The "87 Project" has begun. The 4.1 block is being bored .030. Any recommendations on a merchant for pistons, engine girdle? If I can't find a good deal on a larger turbo, I'll start off with the pte52 I already have. Any recommendations on the cam? I'd really like to get into the 10s with this car (it will be a sunday driver).

Thanks
RS

 

[StageII86]

4.1

Alot of people like to use Venolia pistons with the 4.1. They of course will have to be an all custom affair as no one makes an off the shelf piston for that motor. RJC will be the best source for a girdle. As for the turbo, remember, this motor moves more air than a 3.8. They like a lot of turbo. the 52 will work, but you will probably be happier with something in the Te63 neighborhood.

 

[fast84gn]

want to sell the pte52? if so how much?? just trying to get you the right turbo

 

[FJM568]

Read the 4.1L turbo recipe write-up on the gnttype site...

Good info there on pistons and rings, like going to a 4.000 bore so that you have a wider selection of piston ring choices(not to mention cheaper priced as well, because of the Chevy motor cylinder size)...As was mentioned, pistons will have to be custom made anyway, so having them made for the 4.000 cylinder size, but using the Buick pin height and deck height won't cost any more than just having the .030 over 4.1L piston made(which would end up being a 3.995 bore, since the stock 4.1L bore is 3.965)...

 

[RSTTYPE85]

I would like to purchase a bigger turbo (64, 66). It would really be great if someone wanted to trade for the pte52 + cash.

Thanks Jim, the information did make alot of sense.

 

[sixgun86gn]

After mine blew up on me in the middle of a race at only 17# of boost.No way.You would have to pay me.The only good part was that the exhaust housing could be machined and reused.It spit the turbine right out into the DP.Now it has a new center section a 63-1 comp.wheel and a stage 7 turbine wheel I believe.I know its a 63 compressor but the turbine is bigger than a stage 5.It spools just as good as the 52 did.Maybe when yours blows up you could have it rebuilt the same.It costed just as much as a new turbo anyway.BTW my turbo only lasted 6 months before it went.I'm not saying yours will,but it could.