Engine Swap question....

Jeff Wilson · November 6, 2001

Hey All, I have a '91 1500 with a 4.3 V6 5-Speed.

Anybody know how hard it would be to swap my 4.3 V6 out for a LS-1 out of a 1998 Vette? I can get the engine and A4 tranny for under $1000. Will this even work? Can I keep my current M5 or would it be better to use the A4?

Any advice would be appreciated.

chevy4x4trucks · November 6, 2001

I think that it would be pretty easy, just change out the motor mounts. As for the tranny, go w/ the A5, I dont' know if the tranny you have now would last long w/ such a powerful engine. Just My Opinion

CapnDean · November 6, 2001

Hmmmm...Why so cheap for an LS1 engine & Tranny from a 1998 Vette?

Something's amiss: Unless you have the hook up of all hook-ups of course!

I am not 100% on this but: The 1998 LS1 engine would be compatible because it is still a good ole 350 chevy motor. (I don't think they went to the 5.3 liter engine yet did they?).

A 350 will fit rather nicely into your 91 model truck. There will be a few things you have to deal with like exhaust and some other minutia. Make sure you get the whole deal (all the computer brains etc..). I dunno about the tranny though. I suspect you could engineer it to fit...but why? Why not just hook it up to your existing 5 speed----talk about balls! You'd have em in spades!

I would be more concerned with what might be wrong with a 3 year old LS1 that is soooo (relatively) cheap. That's one hoss of a motor....Was it in a wrecked vette or something?

Let's hear from you as I would be interested in the outcome!

BTW: You will need different rubber on your truck if you stuff that bad lad in there - - I doubt anybody would be able to keep off the gas!

76BBSub · November 6, 2001

Mechanically, shouldn't be a problem, except that the 5-speed manual that currently lives behind your 4.3 will be toast in short order behind the LS1. Also, from a computer/wiring standpoint I think the computer is going to be looking for some feedback from the tranny, which your 5 speed won't provide. Radiator would probably need to be replaced to have the inlet/outlets in the right place, but maybe not. I'm also unsure as to the location of your motor mounts compared to those of the LS1, although that shouldn't be too big a deal even if they don't line up.

Electrically, this would be a nightmare. You must ensure that you get all the computer hardware, wiring, sensors, etc for this to be feasible. One problem is that your gauges are probably not compatible with the LS1 setup, which is all electronic, including the speedo. It could be done, but unless you are already familiar with the LS1 and it's intricacies I'd think about it some more.

Jeff

96 Vortec · November 7, 2001

Fit - yes

electrical - ugh

after all the bloody knuckles and headaches - OH YEAH BABY!!!

CapnDean - that is a 350. As far as I know, there are no plans to put the 5.3 in the Vettes. Although I don't pay as much attention to the new ones as Mervs.