thumper_65590

Hello everyone. I am new to the forum, but have been turning wrenches and modding for years, but these newer engines and electronics are a new creature for me, so I am turning to the experts here to get some advice. I have a 94 GMC Vandura G2500 conversion van. It is a heavy half, 3/4 ton springs but a 1/2 ton rear end. It has a new 4L60E with a 350 TBI thats starting to give me some fits. I am wanting to install a newer, more fuel efficient engine in place of the 5.7TBI. I would also like to keep the tranny I have, as it has less than 4000 miles on it. I have been through many threads and haven't really seen any completed conversions, or really found any information on this type of swap. I don't do too much towing with it, but I am thinking of getting a small camper or a pontoon, so I would like to have enough power and torque to comfortably pull around 2500 lbs. I know I will have to redo my wiring harness, as well as possibly install a stand-alone transmission controller. Any help and suggestions will be greatly appreciated.

76larkman

Welcome to site. Im unsure on fitment of engine in engine bay of van. I have changed sbc in them before. I think I would start by using slider mounts on engine that will go on sbc mounts. I think you probably need to use car intake for clearance reasons(maybe not just a guess rite now). Wiring info can be found on Lt1Swap.com if using truck harness to save money. I would tie in your original van harness on pcm power supply and fuel pump circuit. They already fused in original fuse panel. Use a fuel pump with rite fuel pressure rating in original tank is what I would do. Your going to have to try things as go being non-common swap to see what fits. Your tranny should work. May need adaptor end of crank to center torque convertor. Good luck.

thumper_65590

Does anyone know if the LS computer will run an 94 4L60E? Would a 5.3 be a good engine for this van? If my research is correct, and I am not sure it is, the 5.3LS has comparable hp and torque to the TBI 350/5.7 that is in there now. Am I right in assuming this, or should I just bite the bullet and go up to a 6.0L and a 4L80E combo? I want this to be reliable and fuel efficient as possible. Right now i get about 15 MPG and I would like to get it up higher. Thank you for the help.

76larkman

the 5.3 has more power than your old 350. I believe the iron 5.3 motors have 280hp. I don't think you will have problem with using your tranny just compare tranny plug connectors.

thumper_65590

What years and models should I be looking at for a donor vehicle?

76larkman

99-up Silverado/sierra trucks. 2000-up suv, 98-02 Camaro/firebird

76larkman

99-up Silverado/sierra have 4.8/5.3/6.0 engines, Camaro/firebird has 5.7 98-02

kballs

iTrader: (1)

I'm hoping to swap a LQ4 into my 1980 Chevy shorty in a month or two. I haven't been able to find anything about headers or exh manifolds in a van. As well as what to do about motor mounts besides what was on that roadkill build about using pickup mounts and the hooker ls swap eng side adapter mounts.

I'd like to run headers rather than manifolds, and keep all the truck intake and acct drive setup.

JC4ROXI

I have the same GMC 3/4 ton Vandura 2500 and the transmission was stolen, and I heard the 4L80E tranny is best for this van. My girlfriend likes this van
and thinking to put a rebuilt small block with the 4L80E. She wants to go cross country and want to get more miles. Is this combo workable? Any suggestions? How did your build end up? Would like to know how is your van running now. Thank you.