how many with LS1 in a 88-98 OBS chevy truck
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i have a 1996 Z71 that i replaced the worn out vortex for a stock low milage LS1. swap was very easy. i was just wondering if anyone else has tried it.
Last edited by taqwache; 11-26-2007 at 10:31 PM.
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I have a 97 Z71 and have always wondered about this swap. Any way you could fill me in on some of the details? wiring? gauges? mounts? what acc. style did you use (vette or f-body) exhaust? trans? I have about 200k on mine and she will probably be around for a while. I also know GM PP just came out with a 383e crate motor that is supposed to work fine with the injection.
Ken
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EFI wiring is super simple, just need to splice in a few wires to the stock fuse block. Leave the stock ECM in place to handle the speedometer and cruise, but don't let it control the engine any. I'm sure it'd have the check engine light on at all times if it had one, but that doesn't affect it's speedometer output
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Homer_Simpson (09-06-2022)
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Unless the factory PCM controls the ABS you shouldn`t need it. The LSx PCM can control the speedometer (All the electronic GM speedos use a standard input signal of 4000 Pulses Per Mile square wave DC). The LSx PCM should also be able to control the cruise control, I think that those trucks used the vacuum motor servo cruise control like my car does, the only thing that it gets from the computer is the speedometer signal. The LSx computer can also control the factory check engine light.
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the wireing was easier then i thought. it is kind of hard to explain by typing but i will try. you just buy a LS1 computer, remove each pin one by one from your old 4 connector pcm and insert them in the correct location in the new 2 connecter. for example = tps 5 volt ref, black connector, pin 4, blue wire now goes into red connector pin 20 (i just made up these connectors for an example). this way you end up with all the pin locations for like a 99 camaro but the colors will acually be for a 96 truck. almost all the sensors are the same. you just have to swap the + and - for the crank sensor and relocate it from the front of the engine to the back. the TB and injector wires have to be extended (you will have to buy 8 injector connectors). you will also need to install one harness from scratch for the 8 coil packs but thats it.
on the acc. i just kept it very simple, i just used all the stock 96 ones. you only have to make 2 simple brackets. one for the left and one for the right. you just got to get the stock brackets to bolt up flush to the heads. then if you use a crank pulley and water pump for a 5.3L truck, the belt will line up (custom lenght of coarse). its complicated but simple.
then just make some engine mounts, use a 6.0L truck flywheel, drill it for a small bolt pattern, use a truck intake to clear your custom belt system and your done. for the exhaust, i did not care for headers so i just used stock manifolds and y pipe for a 6.0L SS truck and it fit perfect. after the y, i used a single borla muffler and a dump. with the manifolds and cat's it is very quiet.
this sounds like alot of work but it is (i believe) the cheapest way to do it. on the motor, i used a completey stock 99 LS1 out of a low milage vette, LS6 cam and springs, and stock unported 241 castings. i dynoed it before and after also. HP went from 175 to 285 (110rwhp gain). i also lost almost 200lbs off the nose, gained MPG (17 to 21 on freeway), and gain 2000 rpm (the vortex would drop off fast after 4k but the LS1 pulls to 6.2k easy). i love it but i did lose about 30 or so RW torque below 3500. i really feel that when i am towing but this i mainly a fishing truck so that is ok.
on the acc. i just kept it very simple, i just used all the stock 96 ones. you only have to make 2 simple brackets. one for the left and one for the right. you just got to get the stock brackets to bolt up flush to the heads. then if you use a crank pulley and water pump for a 5.3L truck, the belt will line up (custom lenght of coarse). its complicated but simple.
then just make some engine mounts, use a 6.0L truck flywheel, drill it for a small bolt pattern, use a truck intake to clear your custom belt system and your done. for the exhaust, i did not care for headers so i just used stock manifolds and y pipe for a 6.0L SS truck and it fit perfect. after the y, i used a single borla muffler and a dump. with the manifolds and cat's it is very quiet.
this sounds like alot of work but it is (i believe) the cheapest way to do it. on the motor, i used a completey stock 99 LS1 out of a low milage vette, LS6 cam and springs, and stock unported 241 castings. i dynoed it before and after also. HP went from 175 to 285 (110rwhp gain). i also lost almost 200lbs off the nose, gained MPG (17 to 21 on freeway), and gain 2000 rpm (the vortex would drop off fast after 4k but the LS1 pulls to 6.2k easy). i love it but i did lose about 30 or so RW torque below 3500. i really feel that when i am towing but this i mainly a fishing truck so that is ok.
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Homer_Simpson (08-14-2022)
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Wow, using the old style vortec harness and re-pinning it for the LS1 computer was a unique way of doing it. I think this is the first time I have seen anyone use the wiring from their old motor
.
on the accy brackets too, that is also usually a stumbling block. Any pics of the brackets/setup?
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Michael Hightower (01-19-2020)
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^^ first post and this is the reason i joined the site for info on the swap. Quick question i have a lifted 94 on 37' toyos that is a dd moderate offroader, do you think this swap is a good idea? I have found complete engines and acc. for like 1500 or a touch less on line. Also my brother is a hell of a tuner he said he could get everything just the way i want it if i could get it in there and hooked up. What other cost are associated with the swap? Sry long post i know ty in advance. Sry for slight thread jack.
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I figured it would be an easier swap with it already being fuel injected. My uncle wants to do the same thing when his 5.0 vortec goes in his 98. Using the existing wiring seemed to me to be the wisest decision. Just get a print out from the dealer of both wiring diagrams and plug and play. Hopefully I'll be helping him out shortly.
I too would like to see some pics.
I too would like to see some pics.
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I would love to know more about this swap and see some pics of those acc. brackets. I have 98 4.3L truck that I want to put a used 6.0L into. What if any mods did you have to make to the fuel system?
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Here are some pics of mine when it was twin turbo, I used the speed and performance motor mount plates they have for like $98, Then used 5.3 shorty headers, Just have to grind some on the passenger control arm on the truck, We made a bracket for the tranny mount, I will try to have more detailed pics on the parts later,
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Homer_Simpson (08-14-2022)
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A Flip, how much did the swap cost besides the engine ecu and stuff. Basically askin wut did it cost for like the motor mounts and all the other **** yuo had to have for the swap. One more question. What did you have in the 5.3 when you dropped it in? if it was near stock how was it?