700r4 from 84 c3 vette ?

[Hugeroost]

Guys I am buying this vette, I bought it once already new, now burying it back from my cousin. I wanna pull the motor and tranny together and put both in my 79 lwb. Now I know a bunch o guys here has done it but from what I understand the vette trans has a weird tail housing. So do you guys think this will pose a problem, and what can I do. Fairly stoked about the swap though, I will be going from a wore out 305 with 56hp to a built LT1 with close to 500. Should be fun truck...Roost

 

[Charlie]

 

[Matt69olds]

I think the corvette has a unique output shaft. It’s a fairly easy swap, the extension housing and output shaft should be easy to source.

If your willing to try and swap the shaft yourself, look up drive shell replacement on YouTube. The drive shell is a common failure on the 700 (you may want to replace it before installing it) the output shaft has to come out to replace the shell. That will give you a idea of what’s involved, and if you want to try it or find a trans shop to swap the parts.

 

[Hugeroost]

I think the corvette has a unique output shaft. It’s a fairly easy swap, the extension housing and output shaft should be easy to source.

If your willing to try and swap the shaft yourself, look up drive shell replacement on YouTube. The drive shell is a common failure on the 700 (you may want to replace it before installing it) the output shaft has to come out to replace the shell. That will give you a idea of what’s involved, and if you want to try it or find a trans shop to swap the parts.

Matt, thanks for the info. I would rather pay somebody to do the output shaft swap. So to get the one I need do I go to a junkyard, wonder if they would trade me out, I would think the vette one would be worth more but not sure. I read I'm gonna need to move my cross member back about 2 inches as well, that shouldnt be a problem. Then I will need cables to work the OD correct ? Thanks again

 

[Hugeroost]

Hey Charlie thanks man, cant believe it took me this long to get here considering my love for the square's

 

[Matt69olds]

Call Teal Automotive in Dunkirk Indiana. 18007220215. Ask for Cheryl. Teal specializes in transmission parts, they have everything from late model stuff to old iron.

 

[Hugeroost]

Hey Matt thanks man, would love to talk to somebody that knows. That way they can say ok you need this this and this, they prolly know about that tail on the vette tranny as well, that right there seems to stump everybody i have talked to. I need to get em both pulled and set side by side where i can actually see, but talking to Cheryl will put me miles ahead. A girl huh, i'll be dammed, i can dig it

 

[Matt69olds]

She knows her stuff, she has worked there 25plus years. You may also look for a ATSG (Automatic Transmissions Service Group) book on the 700, it will break down every design change, production change, what parts are compatible, etc. There has been lots of upgrades over the production run of the 700, usually upgrading one part requires several other parts.

 

[K5ride]

I did this swap on my 75 Stepside. I used a 700R4 out of a 87 Vette. I sold the engine and mated the trans to my Gen I 350. Worked great with corvette tail and shaft. I had to move the crossmember back a few inches but 3 out of 4 holes lined up with existing holes in frame. I just drilled another one in the crossmember to align with another existing hole in the frame. They have different length 350 transmissions and depending on which one you have, you may have to change driveshaft length. Mine was about an inch too short. What a difference it makes having the overdrive and lockup converter. I used the Bowtie conversions for the TV cable alignment and the pressure switch / wiring conversion for the lockup. Since your using the stock engine with the trans, you won't need any adapter / conversions. A huge improvement.

 

[yevgenievich]

corvette tail shaft is only about 1" shorter. Usually still works fine in a truck

 

[norman baker]

my 81,82,85 is still running a 350 with lock up, but my 1984 c20 is a 454 tbi with 4l85e out of a motorhome. long legged cruises at 94mph easy low rpm .
but i have an 82 with a dodge manual 3 speed over drive a883 ?
like the 350 lock up

 

[Hugeroost]

I did this swap on my 75 Stepside. I used a 700R4 out of a 87 Vette. I sold the engine and mated the trans to my Gen I 350. Worked great with corvette tail and shaft. I had to move the crossmember back a few inches but 3 out of 4 holes lined up with existing holes in frame. I just drilled another one in the crossmember to align with another existing hole in the frame. They have different length 350 transmissions and depending on which one you have, you may have to change driveshaft length. Mine was about an inch too short. What a difference it makes having the overdrive and lockup converter. I used the Bowtie conversions for the TV cable alignment and the pressure switch / wiring conversion for the lockup. Since your using the stock engine with the trans, you won't need any adapter / conversions. A huge improvement.

damm man thats good news. So from reading i take it when the truck shows to be in drive in the little window behind steering wheel it will actually be in OD, and if i pull it down to 2 it will be in drive. So no need for any wiring at all, i thought i had to run something to the carb, which is Edelbrock 675.

 

[Hugeroost]

corvette tail shaft is only about 1" shorter. Usually still works fine in a truck

thanks man, I hear the 84, and 85 700 is the same but starting in 86 they changed something. I think since i will be pulling motor and tranny at one time out of the Vette prolly should do the same w the truck, then i can just set it in place and have a look see. I had just put an aluminum intake and a Edelbrock 550 or 600 carb, nice valve covers etc i wonder if that motor and tranny is worth anything, it needs a valve job bad thats why i quit driving it, didnt figure it was worth it.

K5, man i cant wait to get this goin, brand new 475hp motor in that old truck lol should be able to punk some fords, and that OD !!

on another note i'm thinking ac, my truck has it but compressor is out, the vette has it and it WAS working when it was parked. That truck has that huge comp on it, i was down for buying a new factory one from dealer but was told they hadnt made those in years. So i will have both complete systems brackets and all though, should be able to make somn work

 

[Hugeroost]

BTW have any you guys seen a Colorado with the 5.3 ? When i found out those trucks existed in 2012 I tracked one down, its a 12 ext cab w Z71 package, silver, absolutely beautiful truck w 40k on it. Garage kept, never even been dirty, thinking about selling it, they are rare, mine is the only one i've ever seen, and they'll never do that again. You know Chevy always considers its fan base, they are well aware how many S10 v8 conversions are out there, i guess when they decided to stop production on the Rado's to retool up for a new version they decided to put some v8's in a few.

 

[4WDKC]

pre 87 700s are weak and need many upgrades for stock production after that. If you want 500 and using an LT1 go straight to the 4l80e dont waste time and money trying to build a stout 700.