Thread: turbo 3.4 dohc with 3400 internals

ok. bought a 95 GTP with a rod and a main bearing spun, and the pistons are junk. I have an entire 3400 in good condition sitting around. people ask me why i dont just put the whole engine in, but i wanna keep the car original as possible. I have decided to swap in the crank, rods and pistons from the 3400, but its gonna put my compression ratio at 7.2:1. that will leave me at about 195 hp according to a calculator i found online. Now, does anyone know of any issues with this idea? And does anyone know the stock injector size for the 2 engines? I may turbo, and i need to know how much psi I can get away with on stock injectors if i drop the CR into the 7's. Thanks

ok, cool. appreciate the info. i cant find it either, i looked everywhere.

Pistons from a 3400 have a 28.6 cc dish vs a 5cc dome, and will lower my compression to 7.2:1. Stroke is 3.31 vs 3.307 on the dohc. Pistons stick out .02 instead of a .0095 recess, bore is equal, crank main journals are equal, rod journals are equal, rod length is equal.

Ok. I have the 3400 engine. Ill take pictures of the build. The internals are going in this weekend. Ill let ya know how it runs.

I used the old crank sensor and made a crank trigger out of my crank pulley, a degree wheel and a die grinder with a cut off wheel attached. Made the ckp bracket out of a random piece of
1/8" metal strap. Took a lot of trial and error to adjust properly. This is the video of the first time it ran without sputtering and backfiring through the intake. A little tweak of the air gap I done after this video straightened it up. YouTube - Lq1 3.4 GTP with 3400 LNJ Equinox internalsYouTube - Lq1 3.4 GTP with 3400 LNJ Equinox internals

Originally Posted by ctracer

congratulations on the build. have you taken it for a spin yet?

Thanks. I dont have tags but I floored it from where it sat in the garage and it barked pretty hard as nd I went down the driveway with it on the floor. Done it 5 times.

Nice work man