Anyone replace a 4.3 with a V-8 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Chevyman63 · 03-30-2007, 05:02 PM

A guy that works for me has an '02 1/2 ton 4x4 with a tired 4.3 in it and would like to know how big of a PITA it is to swap, if possible at all. Or would it be smarter to rebuild the 4.3?
Any help would be greatly appreciated.
Thanks.

87 STEPPER · 04-04-2007, 07:00 AM

Im not sure what that truck uses for a fuel delivery system but that would be the only problem of the swap.

If that is a newer vortec set up then i would leave it alone and just get a GM 4.3 crate eng.

It can be done but theres a helluva lot of work and expense involved to do that

Other than that it's just a R&R only your putting in a V8 instead of the V6.

droppedgmc · 04-04-2007, 01:15 PM

the newer trucks use the same fuel system. i know lots of people that have already made the swap. you'll need the v-8 engine harness and computer. trans should bolt right up

87 STEPPER · 04-04-2007, 04:46 PM

Quote:

Originally Posted by droppedgmc

the newer trucks use the same fuel system. i know lots of people that have already made the swap. you'll need the v-8 engine harness and computer. trans should bolt right up

That's the expence part i was refering to the harness & ECM arn't cheap and i think you will also need a V8 Intake manifold and FI spider assy. cuz the V6 stuff isn't gonna fit.

All this stuff can be found on Ebay but unless you get it new your asking for headaches.

I think i'd stay with the 4.3

droppedgmc · 04-05-2007, 12:03 AM

you can find complete running 4.8/5.3 engines with harness and computer in the wrecking yards for $1000.00-1500.00

Chevyman63 · 04-05-2007, 05:56 AM

Thanks to all for the info...it looks like keeping the 4.3 will be the least amount of work. And installing a Superchip or something like that might be a good place to start. Then rebuild the 4.3 later.
Once again thanks for all the input.

Pyrotechnic · 04-05-2007, 01:35 PM

You could build a hopped up 4.3 with a cam, some head work, and a computer reprogram. Good time to do it during the rebuild.

03-30-2007, 05:02 PM	#1
Chevyman63 Can't wait to retire!! Join Date: Feb 2003 Location: Corunna, MI Posts: 1,575	Anyone replace a 4.3 with a V-8 A guy that works for me has an '02 1/2 ton 4x4 with a tired 4.3 in it and would like to know how big of a PITA it is to swap, if possible at all. Or would it be smarter to rebuild the 4.3? Any help would be greatly appreciated. Thanks. __________________ 2009 4x4 Chevy Crew Cab 6.0 1989 4x4 Siverado (270,000 miles) 1972 4x4 Blazer 2007 Chevy Cutaway 1 ton 1970 Corvette (sons project) RIP - CLR 10/11/09

04-04-2007, 07:00 AM	#2
87 STEPPER STILL PLAYS WITH TRUX Join Date: Nov 2002 Location: Melbourne, Fla. Posts: 2,764	Re: Anyone replace a 4.3 with a V-8 Im not sure what that truck uses for a fuel delivery system but that would be the only problem of the swap. If that is a newer vortec set up then i would leave it alone and just get a GM 4.3 crate eng. It can be done but theres a helluva lot of work and expense involved to do that Other than that it's just a R&R only your putting in a V8 instead of the V6. __________________ ~~Bruce~~ MY 87 STEPPER MY 99 2D/WD TAHOE

04-04-2007, 01:15 PM	#3
droppedgmc Truck Enthusiast Join Date: Dec 2006 Location: Arlington, WA Posts: 1,346	Re: Anyone replace a 4.3 with a V-8 the newer trucks use the same fuel system. i know lots of people that have already made the swap. you'll need the v-8 engine harness and computer. trans should bolt right up __________________ '85 swb

04-05-2007, 12:03 AM	#5
droppedgmc Truck Enthusiast Join Date: Dec 2006 Location: Arlington, WA Posts: 1,346	Re: Anyone replace a 4.3 with a V-8 you can find complete running 4.8/5.3 engines with harness and computer in the wrecking yards for $1000.00-1500.00 __________________ '85 swb

04-05-2007, 05:56 AM	#6
Chevyman63 Can't wait to retire!! Join Date: Feb 2003 Location: Corunna, MI Posts: 1,575	Re: Anyone replace a 4.3 with a V-8 Thanks to all for the info...it looks like keeping the 4.3 will be the least amount of work. And installing a Superchip or something like that might be a good place to start. Then rebuild the 4.3 later. Once again thanks for all the input. __________________ 2009 4x4 Chevy Crew Cab 6.0 1989 4x4 Siverado (270,000 miles) 1972 4x4 Blazer 2007 Chevy Cutaway 1 ton 1970 Corvette (sons project) RIP - CLR 10/11/09 Last edited by Chevyman63; 04-05-2007 at 05:57 AM.

04-05-2007, 01:35 PM	#7
Pyrotechnic Registered User Join Date: Feb 2007 Location: Austin, TX Posts: 3,930	Re: Anyone replace a 4.3 with a V-8 You could build a hopped up 4.3 with a cam, some head work, and a computer reprogram. Good time to do it during the rebuild.



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