So, how difficult is an LT1 swap?

[divorced]

I have a '95 C1500 with a TBI 4.3 and 191,000 miles

My friend picked up a '95 Buick Roadmaster with a LT1 5.7 and 110,000 miles.

He needs my 4.3 and wants to trade me his LT1 for it. The LT1 has 260 HP/330 lb ft torque, similar to a Vortec 5.7 which has 250 HP/335 lb ft torque. I may be getting the 4L60E with it, otherwise my 4.3 has a 4L60E that may work.

So, how difficult/expensive is this swap? Would it be easier to put it in an older carbed truck? Should I just keep my 4.3?

These aren't the actual engine, but it's what it looks like:

 

[sweetk30]

we did one at the shop one time. painless harness , electric fans , no a/c with custom made ideler pully as it would hit the frame. custom p/s lines and welded the pass side motor mount to the frame as the lt1 is diffrent on the right side. then we made up the fuel lines and swaped in the lt1 fuel pump on to the stock truck sender.


runs like a champ. can get pics for ya if needed.

 

[divorced]

Thanks for the information. Do you remember about how much $$$ it cost for the swap? I will let you know if I need pics, I may not actually trade for it.

 

[Russell]

Guess how much you'll think it will cost, then triple that number :P

Thats what happened with my TPI swap anyways...

It may be cheaper for you, cause you'll have the complete running car there. But yeah, the electronics may be a bit of a pain in the butt. I don't know if you can use the factory harness from the car like on a truck.

 

[pauly383]

If you had a V-8 , the mounts would bolt to the LT1 block

 

[1-ton]

any project like you are talking about is going to be time consuming, and at least somewhat expensive to do it right. If there is any way you can get your hands on that engine without trading your engine, I would do it.

 

[sweetk30]

If you had a V-8 , the mounts would bolt to the LT1 block

no thay wont. the pass side mount is fliped and moved back on the block. there is 4 cast bolt holes . the front one is for the lt1 serp belt mount stuff. then the factory mount to the block is fliped upside down and moved back a inch or so. thats why we had to do the weld it to the frame trick.

other than that its not to bad. he drives it alot. it will keep up to his stock lt1 full police issue cop car that was retired, that he got and restored. its the same year as the swap motor.

 

[79k20350]

i did the swap into my 84' it was real easy to do (almost to easy) I sent the harness to www.lt1350.com and got it back ready to go. i eliminated all emissons systems and they set the harness up for that. basically its 4 wires (4 connections besides all sensors, 1 ground, 1 ignition hot, 1 constant hot and 1 for fuel pump relay) to hook up when you get the harness back. then just plug the harness into the factory sensors. i did have to notch the frame though to clear the belt, about a 2" wide cut on the pass. side framerail, and about 3/4" deep. i reinforced it so its all good now. you also need an ac delte pulley so you can move the motor mount bracket to the correct location. Youll need a capable fuel pump (need 40psi) You need to hook up the cooling system properylyt too. theres a steam tube, then the heater hoses and rad hoses. i found it easiest to get a cool system diagram to make it all work. if you have any specific questions just ask, i love my setup!

 

[79k20350]

yes a factpry v8 mount bolts directly to a lt1 block. all you need is an ac delete pulley to get rid of the compressor

 

[pauly383]

Its 1 1/2 inches back . But you remove the compressor there , and put it on the drivers side , like on the vette . And where trucks usually have the compressor anyway . Or use the 1LE a/c delete bracket

But older mounts will TECHNICALLY fit

 

[beater_k20]

no thay wont. the pass side mount is fliped and moved back on the block. there is 4 cast bolt holes . the front one is for the lt1 serp belt mount stuff. then the factory mount to the block is fliped upside down and moved back a inch or so. thats why we had to do the weld it to the frame trick.

i bought this stand for $20 at a swap meet, i've got one identical to it bolted to my L31, both bolt right up, so the stock V8 truck mounts will too. the LT1 doesnt leave room for a motor mount, but with a 1LE idler pulley from a Camaro, the compressor would be gone, and it wouldnt be an issue. wiring harness is going to be your only real problem. V8 exhaust will bolt right up to it. you'll also want to put a higher pressure pump in the tank, but i believe that is a direct bolt in as well.

 

[sweetk30]

o.k fair. the one we bolted in was a 95 from a police special wreck. it had a bracket boss solted to the stock upper front hole. there must be a few diffrent styles out there.

in the second pic you can see the other bolt boss in the block. this is where the mount would be fliped and bolt to.

 

[dave_90_blazer]

http://coloradok5.com/forums/showthread.php?t=151095


here's mine in a 90 K5
get VATS tuned out of the computer, as well as EGR, AIR, and VSS

then you need to run something like 5 wires(2 for Injector feeds, 1 for O2 Heater, 1 for 12v constant, and 1 for 12v key on), a few others are needed, I used a fuel pump for a 91 camaro TPI(It fits in the stock sender, use a piece of high pressure hose from the pump to the line on the sender, i used the OE one, and it sprung a leak the next day), it is wired to run key on(to lazy to wire to the PCM), plus you need to run a electric fan

one thing is you need to work on if fuel lines, they are om\n the drivers side of the engine, and use a push style quick connect, but it you have the lines fron the car, you can m,ake something work(I used the lines from the camaro the engine is from, were about 4-5 feet long,m had quick connects at both ends, and the sell the metal part of them at auto parts stores)

 

[79k20350]

its a 95, they didnt have vats until 96. you dont need any of the emissons systems taken/ deleted from the computer, it will not throw the comp into limp mode. i havent had a problem in over a year

 

[beater_k20]

its a 95, they didnt have vats until 96. you dont need any of the emissons systems taken/ deleted from the computer, it will not throw the comp into limp mode. i havent had a problem in over a year

you dont need the emissions systems removed if you run them, otherwise you're hurting performance.

 

[79k20350]

I got in contact with a few differant companys that do computer tuning and all of them ave said that not running the emisson should not hurt the systems because it wont send the computer into limp mode. im not sure why but from what i have been told from the pros its ok.

 

[Russell]

Should be tossing codes left and right though...

Its typically a good idea to get them shut off, cause they all do have some effect on the engine when they are turned on and off, and the computer will be expecting those effects, and if it doens't see them, it should toss a code if it is working properly. Infact, my 89 tosses a code cause the cam is so bumpy that it constantly bumps off the stall prevention algorithm at 600 rpm

 

[79k20350]

the comp prolly is throwing codes but its nothin that is going to throw it into limp mode. that being said my comp is out right now and on its way to get retuned, i m getting it tuned for my exact setup, ill let you know of any dfferances when i get it back

 

[dave_90_blazer]

its a 95, they didnt have vats until 96. you dont need any of the emissons systems taken/ deleted from the computer, it will not throw the comp into limp mode. i havent had a problem in over a year

wrong, pretty much all GM cars from 89 up had VATS

 

[beater_k20]

wrong, pretty much all GM cars from 89 up had VATS

i know for a fact that my '94 Caprice didnt have it, and my 95 and 96 Grand Ams didnt have it. come to think of it, neither did the 89 and the 94 Berettas we had. late third gen F-bodies got it however, as well as all fourth gens.