Got a question. I'm thinking of the LS1 swap, but my question is will the 700R4 bolt up to the LS1? I know the Turbo 400 will, but i'm not sure about the 700. I know the 4L60E or T56 is better, but the 700 will only be a temporary thing. Thanx

 

No. The 400 won't either.

You could use a motor plate; that's how people put 400s behind LS1s; that should work equally well on your 700.

 

The 400 does without a plate. We do them alot at work. Where can i get a plate to get the 700 to bolt up? Thanx

 

Not sure where you work but you might wanna ask some of the guys at work cause I'm sure they're not bolting 400's to LS1s. A 400 and 700-r4 have the same bellhousing bolt patterns so they will each bolt to the same motor and neither will bolt to an LS1

 

Go try to bolt it up and see what happens. Then come back and tell us.

 

Good answer

 

Sorry, I must be mistaken. It's just that I never noticed the plate . Anyway, so where can I get ahold of one of these plates?

 

It would be the same plate the people at your work are using to bolt the 400's up

 

I got another question in regard to bolting transmissions to engines. Will a TH-350 bolt right onto the LT1 motor or do I have to get a plate?

 

A Chevy T-350 will bolt right up to any Chevy V8 except a LS1.

All Chevy V8s except the LS1 have the same BH bolt pattern, so the pattern on all the different trans models is the same too.

 

Guys we've doen about a dozen T400 swaps into LS1 cars... WITHOUT an adaptor plate. Just dropped one of ours out two weeks ago, still no plate there Couple twin turbo cars, fastest stock bottom end LS1 in the country.... all T400s with no adaptor plate. They have a six speed tranny crossmember, but no adaptor plate

~Jeff from FBodyCentral.com

 

Well this got my gears turnin' so I checked out previous issues of CHP mag and ran across a few tech articles and letters about tech info.

The LS1 and LT1 T56's are totally different. They are not interchangable at all. That's what the tech article said.

As far as the TH400 bolting up, I couldn't find any info. But there was a letter from a guy who wanted to put a 5.3L Vortec in a 72 Chevelle. Don't ask me why? Anyway, he has a Muncie M21 and wanted to know it it would bolt up. The response was 'Yes, minus one bolt.' That's not an actual quote, so don't quote me on that. But he did say that the guy would need a custom flywheel that Centerforce makes because the LS1 is offset 2" deeper.

As some of you may not know, the truck Vortec series uses the same block whether it's a 4.8L, 5.3L or a 6.0L, albeit iron, so the bolt pattern on the rear is the same as the LS1.

If a Muncie M21 will bolt up, so will a 700-R4, a 2004-R, a TH350, a Powerglide, and a TH400. What bolt he was speaking of I don't know. Hopefully not one on the bottom edge.

Since it wasn't a response (the answer to the letter mentioned above) that had to do with automatics, I don't know if any special TQ or flexplate is required to compensate for that 2" offset. Maybe the guys you work with know?

 

Yeah, there is something with one of the bolt holes. If i remember correctly, there's one of the bolt holes on the bell housing that isn't used because one of the cylinders is on the other side ! That may cause a little compression loss . As far as the offset, i'm not sure. All of the guys here have aftermarket clutches an torque convertors anyway. When we order them, we dont have to specify the offset. We just order a TQ for a th400 and it works. CamaroDriver, I apprecitate you sticking up for me on this one

 

Well I have both an LS1 and a L98 in my garage and from what I can see you are going to have a tough time putting a bolt in the 12:00 clock position on the T400. It doesn't have a hole there and the LS1 does. To make matters worse you would have to do alot of hole slotting to acount for the 10 degree offset in the second set of holes from the bottom of the tranny.

 

So I guess i should go tell all the guys with TH400s that are running 11's that their trannys dont' work? Uh uh! I posted this to see if anyone had done an LS1 swap and kept the 700 and to see how they held up to the power. Thanx for nothing.

 

Well since you apparently know your answer and think everyone else is stupid, I think this post is done.