swapping an ls4 into a 97-03 gp

**NineD9GT** · 06-26-2010

Has anyone tried this yet? I don't think it would be that hard. I spun a bearing in my l67 that I swapped into my 99GT, now I'm looking at my options. Got drinking a couple last night, and bs'ing. "Hey, what's stopping you from swapping an ls4 into that hog?" I said "hmmm, I guess not having one right now." I'm 90 percent sure it will fit. Would be nice if the whole cradle would bolt up. Just an idea right now, what do you guys think?

**Poil336** · 06-26-2010

the idea has crossed my mind as well, i think it would be a pretty nice sleeper. i haven't looked into the ways to actually do it though. the biggest drawbacks that come to mind would be extra strain on the transmission and a small aftermarket for the ls4. i'm sure you could build an l67 that makes more power than an ls4 pretty easily, just don't know about price. i think it's worth looking into

**NineD9GT** · 06-26-2010

Well, I would swap the 4t80e in with it. I was thinking of doing the swap, and keeping the 5.3 in long enough to work out the bugs. Then, swap in a ls1 or ls2. You can pick up a 6.0 around here pretty cheap out of a truck. I think that would get work done.

**OH4CompG** · 06-26-2010

I think an LS2 or LS1 would probably be easier. That way you wouldn't have to worry about DOD

**Poil336** · 06-26-2010

haha oh yeah, that would do work. you'd be sitting at an intersection just spinning the tires when the light turns green. didn't they shorten the crankshaft or something to fit the ls4 for transverse applications? an ls1 or 2 would probably have a lot more fab work. totally worth it.

**NineD9GT** · 06-26-2010

My friend does computer tuning, so he could just eliminate that. I think I'm going to have to do this. Now, I'm getting excited. haha

**matt5112** · 06-26-2010

someone on here is swapping in an ls4 and just swap the LS4, cam it (get rid of DOD), LS6 intake, TEP tranny and you should be good to go.

**sic6** · 06-27-2010

The crank ends are machined to fit in the w body application. The front accessories are also slimmer than typical Ls engines to provide clearance. As far as mods goes if you don"t mind getting rid of D.O.D then you can basicly mod it just like a Ls engine, heads, cam, certain intake manifolds and other mods. You could also overbore the cylinders to get 5.7 displacement since the 5.3 and 5.7 have the same stroke. You will be limited however by header design due to the fwd layout. I say do it, it will be a fun project to do.

**03GTPLE** · 06-27-2010

Here's the link on someone that did it a looong time ago. Tom K of Texas is the proud owne

pic:

**03GTPLE** · 06-27-2010

here's gm's version of an LS1 in a 99 Impala SS (prototype)

LS-1 Powered Impala SS - Feature - GM High-Tech Performance

**SuperSport** · 06-27-2010

Originally Posted by 03GTPLE

here's gm's version of an LS1 in a 99 Impala SS (prototype)

LS-1 Powered Impala SS - Feature - GM High-Tech Performance

Ive personally driven that exact car. My dad was on that project. They did a 00 Monte SS with the LS1 too.

**hklvette** · 06-28-2010

The LS4 uses a different bellhousing pattern than the other V8s. Fiero guys using LSxs use adapter plates, but they always bolt up to manual transmissions. Not sure what issues you run into trying to use an automatic. Also, the starter for the LS4 is mounted on the transmission if i'm not mistaken.

**blueguy** · 06-28-2010

You think Torque steer is bad with a 3800...LOL at a V8. I'll still win in my V6 car. Good luck.

**QwikGT** · 06-28-2010

its a waste of time and money, you need to rewire the car for it to use the CAN bus because the engine is not OBD2. also that engine puts out A LOT of heat, factory GXP's come with 6* of KR or more from the factory, not to mention 210* IAT's and over 250* coolant and trans temps after a few WOT runs. a 3800 with a blower is cheaper and faster than a 5.3, you want an LS buy an F-Body

**NineD9GT** · 06-28-2010

Just trying to be different. F bodies are a dime/dozen. How many 97-03 v-8 grand prixs do you see? *still in research mode, but I think I need to try it.