ls1/t56 into 70 LeMans
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Teching In
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ls1/t56 into 70 LeMans i started the swap a few months ago but i just got my high speed internet hooked up finally so now i can post some pics and stuff for you guys out there doing this swap. the car is a 70 LeMans sport that came with a 350 pontiac, th350 and a 10 bolt. i built the car about 5 years ago when i was about 16 so the paint and interior are all done (although the bodywork is a little sketchy) but mechanically it was a mess, i had only drove it a handfull of times in the last 3 years. so i ended up with a ls1 and T56 out of a 2000 WS6. i will be using the harness out of it as well as the seats and the brake booster. her are the pre swap pics
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Teching In
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i am using the brp style mounts with the f body pan and edelbrock headers. i have the motor in with the headers on and they do work with the brp mounts but how i have the engine set the first tube on the one side just barely hits the steering shaft. i dimpled the tube a bit and it should wok fine. if i had positioned the motor a little more to the one side when i drilled the mounts it probably wouldnt have been a problem. ill try to get some pics of that up this weekend
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Yeah please do, but then again you have your body off the car. I heard the brp mounts raise your engine in front, just want to see how yours sits I am going with edelbrock plates/headers with milodon oil pan..hopefully I dont have to "dimple" anything with my conversion but its definitly dimpling my wallet, 
BTW dont mean to hijack the thread, I have a ls1 S&P modified oil pan if anyone is interested, oil capacity isnt going to cut it
BTW dont mean to hijack the thread, I have a ls1 S&P modified oil pan if anyone is interested, oil capacity isnt going to cut it
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Teching In
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as far as im concerned the engine came out of a pontiac so im saying that its a pontiac motor haha. here are some pics of it all painted up. ill try to get the pics of it with the headers once i get my camera figured out
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Teching In
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with the style of mounts i used the tunnel needs to be cut, i raised it about 2.5 inches and i still barely clears in some places. ive heard that if you use a differnt style of mounts you dont have to do it but i find that hard to believe since the 6 speed is so bulky. i made my own brp style adapters with the tall/narrow style mounts
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here is the brake booster out of the trans am that i modified to fit. i cut the studs off of the booster and then i got a piece of flat steel and i drilled the lemans booster bolt pattern in it and then i welded it to the TA booster and drilled the top hole through the boosters mounting pad. i hope that makes sense. i also welded the lemans booster push rod onto it with a round tube over to for reinforcement. the last picture is my line lock that ill be hooking up soon
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here are the pics of my computer mount job and my fuse/relay box mount job. the fuse box is one of the underhood ones from the trans am and i wired it to the harness myself. i mounted the fuse box to a bracket that attaches to the bottom of the dash and to the top of the heater control box. to mount the computer i welded four c shaped brackets and ran straps through them and across the computer. it seems to hold it pretty good. it think it will hit the glove box so i might have to cut a bit out of it. last picture shows where the wires come through the firewall, the hole will barely be visible once its all together
It looks like your overall plan is very similar to mine. I'm also using BRP-style mounts and Edelbrock headers for the LS1/T56 combo in my '71 Chevelle, and like you, I'm going to make use of everything I can from my '99 T/A donor car.
What size of hole did you drill in the firewall to run the harness through? Where did you get the grommet?
What size of hole did you drill in the firewall to run the harness through? Where did you get the grommet?
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i think the hole is about 1 3/4", jut big enough for the pcm connectors to fit through one at a time. the grommet is just the one out of the donor car for the harness wires running through the firewall. i just cut out the center and made a slit in it, works good. yeah ive used alot of parts off of the T/A, seats, booster, trottle cable, underhood fuse box. the edelbrock headers are pretty nice, they hang a bit lower than i would have liked though and your going to have to dimple one of the tubes