- Moderator
- #1
KANE
Moderator
- Joined
- Mar 2, 2002
- Messages
- 3,244
- Location
- KY
- Corvette
- Dark Blue 1982 Trans Am(s): Polo Green 1995 MN6
I'm going with a GMPP motor...
I've had to change my direction... again.
I remember hearing the expression that everything is up for discussion until execution starts. It is hard to turn back once you've started down a particular road. This has been a saga for sure as I've gone back and forth between rebuilding my block, the GMPP 330hp HO, and then the GMPP 290hp motor.
Ultimately, the goal of my engine project is to hit 300hp- and not spend a mint doing it. I'm never going to race the car so it doesn't need to have over 350hp anyways.
It looks like I can get that much using the GMPP 290hp. Yes, it is essentially an over-the-counter L82. The 290hp motor does have less compression than the L82- but the heads actually flow a little better than the L82 heads (hence the 290hp rating). I think with a set of 1.6 roller rockers I'll be there.
I've been studying the cost / return ratio of the 330hp HO against the 290hp motor. To get the HO into my Vette, I'd need to spend another $700. Total cost would be $1100 over the price of the 290hp motor. That includes a new flexplate and Vortec intake. For that much, I could port a set of Iron Eagle heads and put them on at a later date- and come out better than the HO.
Well, I recently saw a cam swap that pushed the low squeeze motor over up to 305hp. I've studied aspects of the cam and compared it to adding roller tip 1.6 rockers. It appears the rockers would net the same results.
Best of all, going this route will free up a lot of cash for other things... like new trailing arms, front coils, etc.
I've had to change my direction... again.
I remember hearing the expression that everything is up for discussion until execution starts. It is hard to turn back once you've started down a particular road. This has been a saga for sure as I've gone back and forth between rebuilding my block, the GMPP 330hp HO, and then the GMPP 290hp motor.
Ultimately, the goal of my engine project is to hit 300hp- and not spend a mint doing it. I'm never going to race the car so it doesn't need to have over 350hp anyways.
It looks like I can get that much using the GMPP 290hp. Yes, it is essentially an over-the-counter L82. The 290hp motor does have less compression than the L82- but the heads actually flow a little better than the L82 heads (hence the 290hp rating). I think with a set of 1.6 roller rockers I'll be there.
I've been studying the cost / return ratio of the 330hp HO against the 290hp motor. To get the HO into my Vette, I'd need to spend another $700. Total cost would be $1100 over the price of the 290hp motor. That includes a new flexplate and Vortec intake. For that much, I could port a set of Iron Eagle heads and put them on at a later date- and come out better than the HO.
Well, I recently saw a cam swap that pushed the low squeeze motor over up to 305hp. I've studied aspects of the cam and compared it to adding roller tip 1.6 rockers. It appears the rockers would net the same results.
Best of all, going this route will free up a lot of cash for other things... like new trailing arms, front coils, etc.
