LT1/M6 swap in a C3
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LT1/M6 swap in a C3
Has anyone ever swaped a FI LT1 with a T56 into a C3? I found a cheap 78 Corvette that has the stock 350, with 4 speed. I was wondting to know if its super hard or just takes alittle work, ive never seen it done...ive seen a LS1 swap, and heard there a pain in the ***. So any help works thanks
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From: Columbia Missouri
Originally Posted by DevilNDisguise346
Has anyone ever swaped a FI LT1 with a T56 into a C3? I found a cheap 78 Corvette that has the stock 350, with 4 speed. I was wondting to know if its super hard or just takes alittle work, ive never seen it done...ive seen a LS1 swap, and heard there a pain in the ***. So any help works thanks
There are a couple problems with a direct swap but it can be done with some changes and mods. Do a search, advanced search including archives, for LT1 swap, and you should get a lot of good threads.
I think the biggest problem is the serp system brackets and accessories won't fit in the C3. You'd have to adopt the brackets from a C4 or third Gen Camaro.
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From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Originally Posted by Durango_boy
You'd have to adopt the brackets from a C4 or third Gen Camaro.
You would have to use a 1993&up C-4 pulley system. I am doing that swap now. Its just work, not hard at all. Yo can e-mail me for more info..
The shifter will be moved up about an inch, and centered in the console.
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From: San Diego CA
From what I've gathered by reading previous posts about it here's what I can see definitely has to be done.
Gotta use the late model C4 LT1 pulleys so they don't interfere with the suspension.
Gotta get an electric fuel pump and re-do the fuel lines.
Wiring stuff up becomes a little more in depth (like for the key start, guages, and cruise control)
Gotta cut a hole in the transmission tunnel for the shifter, since it's in a different place. (There may be an adapter to make it line up better now though)
You'll need a different crossmember for the transmission.
Make sure you get the computer and wiring harness with it, or some more expenses will come up.
I think that's the gist of it. Megaladon correct me or add more if I'm wrong.
You're more of the expert on it than I am since you're actually doing it. 
Looks like you're doing it very well, too, by the way. 
Gotta use the late model C4 LT1 pulleys so they don't interfere with the suspension.
Gotta get an electric fuel pump and re-do the fuel lines.
Wiring stuff up becomes a little more in depth (like for the key start, guages, and cruise control)
Gotta cut a hole in the transmission tunnel for the shifter, since it's in a different place. (There may be an adapter to make it line up better now though)
You'll need a different crossmember for the transmission.
Make sure you get the computer and wiring harness with it, or some more expenses will come up.
I think that's the gist of it. Megaladon correct me or add more if I'm wrong.
You're more of the expert on it than I am since you're actually doing it. Looks like you're doing it very well, too, by the way.
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From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Originally Posted by Kalway
and re-do the fuel lines.
There are a millon little things you have to do as with any FI swap..
If anyone has questions just e-mail me.. I think I pretty much shown the basic start to a LT1 swap.
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Wow thats a tighter fit than i thought it would of been, why did you go with the GenI SBC Vc's? Looks like there gonna hit the brakebooster under hard acc.? Also is that a T56 or the ZF tranny? Also what headers are you gonna use? or just gonna use stocker manifolds? But im guessing you could use genI sbc C3 headers and have the heads ported so they would bolt up?
I dont know, for what i want it for i believe a C5 would probily be my best bet
I dont know, for what i want it for i believe a C5 would probily be my best bet
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From: Columbia Missouri
Originally Posted by DevilNDisguise346
I dont know, for what i want it for i believe a C5 would probily be my best bet
Well there are several members that have installed an LS motor in their C3. I think it's a lot harder, but they could tell you that better than I.
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From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Originally Posted by DevilNDisguise346
Also what headers are you gonna use? or just gonna use stocker
stock exhaust on a killer ride
GEN-1 headers work.Nothing hits. Nothing is stock on this car, But its all GM parts
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From: San Diego CA
Originally Posted by MEGALADON
Only thing you got wrong. You have to use a 82 sending unit with a E-pump. Bolt right up.
There are a millon little things you have to do as with any FI swap..
If anyone has questions just e-mail me.. I think I pretty much shown the basic start to a LT1 swap.
There are a millon little things you have to do as with any FI swap..
If anyone has questions just e-mail me.. I think I pretty much shown the basic start to a LT1 swap.
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From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Originally Posted by Kalway
Don't you have to reroute the last bit of line up to the fuel rail? I'd imagine you'd have to replace parts of the fuel line for the fuel pump, as well.
is the hydraulic clutch bracket I had to make.
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From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Originally Posted by Kalway
I'd imagine you'd have to replace parts of the fuel line for the fuel pump, as well.
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From: Columbia Missouri
Originally Posted by MEGALADON
Fuel pump is in the tank with a 82 unit. All 82's were crossfire FI. You just need a higher GPM pump.
So MEG, will the pump unit from an '82 fit in a '77 tank? Just upgrade the pump and that's it? Can you suggest a pump?
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From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Originally Posted by Durango_boy
Just upgrade the pump and that's it? Can you suggest a pump?
your doing and they got the right part for you!!
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From: Columbia Missouri
Originally Posted by MEGALADON
Yup, S&P can do that for you. Just call them tell them whatt
your doing and they got the right part for you!!
your doing and they got the right part for you!!
Sorry but what's S&P? I probably know I just can't think of it.
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From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Originally Posted by Durango_boy
Sorry but what's S&P? I probably know I just can't think of it.
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From: Columbia Missouri
Originally Posted by MEGALADON
Cool, thanks. I bookmarked it, so I can call them at my leisure. Appreciated.