Rebuilding a engine

I blew up my engine awale ago and i wanted to rebuild it and make it take the power it was a 2000 grand prix gt i know there not the same as the gtp engines but is there anyway to buy connecting rods that were used out of a gtp and the pistons or is there a big diff between them two?oh yah im boring it out.10". anything that i need to do to make it strounger pretty much thanks.

If you are boring it over the GTP parts wont work, they are stock sized just tougher.

If you need it beafed up go for forged pistons/rings and connecting rods. Probly wouldnt hurt to get performance(forged) high quality crank and cam.
Performance bearing tooo!

Then you'll need to toughin the heads/vavle train.

It will be pricey, even though you do the work.
Performance parts are not cheap.

Good Luck

The big difference between the L67 and L36 engines is the compression ratio. A stock L67 engine has lower compression than a L36 as a result of the piston design and provisions for the supercharger.

L36 = 9.4:1

L67 = 8.5:1

well i saw 3800 Performance have pistons for my car if its bored out or not and i connecting rods i was just wondering if that would work out? so the only diffrence is the pistons and rods right i mean will they fit in a gt motor from a gtp if i dont bore it out i just need something strounger set up then the gt setup

The big difference between the L67 and L36 engines is the compression ratio. A stock L67 engine has lower compression than a L36 as a result of the piston design and provisions for the supercharger.

L36 = 9.4:1

L67 = 8.5:1


I thought the L67 was 8.1:1
I'll take note of this !
I knew with boost it needs to be lower .

well i saw 3800 Performance have pistons for my car if its bored out or not and i connecting rods i was just wondering if that would work out? so the only diffrence is the pistons and rods right i mean will they fit in a gt motor from a gtp if i dont bore it out i just need something strounger set up then the gt setup

Actual GTP internals are not that different really, other then compression ratio.

Which unless you're going to run boost, you really dont need Full performance forged pistons & rods :grinno:

What was 3800 Performance wanting for parts ?

You need to be careful when modding the internals of a computer controlled engine. Any changes you make could actually hurt performance by making the computer detect knock and adjusting fuel trim and timing to compensate. The stock internals of the 3800 are prety stout. The most bang-for-the-buck mods are hi-flow cat, u-bend delete, reprogrammed PCM, and if you must mess with the mechanicals, different ratio rocker arms. The crank, rods and such are good for 6500 or better, and really would be a waste of time, unless you plan on running nitrous.

As Rich says, any internal changes like planned, require complete rebalance, all the components on the L67 are hp components, rods, crank and pistons, basically very little of these 2 engines interchange. Bnaylor can fill in the gaps here as to the issues involved.

I wasnt certain myself what was different.

Havent had to many 3.8's apart if that says anything.
They are pretty tough !