Transmission issues

[Thumpin455]

I have a 700R4 behind the 455 I just stuffed in the 70 GTO. My driveshaft is too long and I wont be cutting it to fit since its perfect for either a th400 or 2004R in any A body.

I have a BOP th400 sitting here that needs rebuilt, and a chevy th400 from a truck. It would take me a day to swap the guts over to the BOP case and then a shift kit to get valve body gaskets. I would have to pull the adapter plate, because the truck uses a different output shaft than a car so if I am going to tear down a th400 I might as well use a BOP case. The rear has 3.42 gears and I wanted the OD for easy cruising, so I would really rather have the 700R4 or 2004R in it.

I also have a 2004R that I just pulled out, it needs some attention but it does work. It just wouldnt hold the power above 1/2 throttle in that heavy car with that engine. This engine would be worse, but I dont plan on drag racing it any time soon I just like the .62 OD.

Anyone have a driveshaft laying around?

What should I do? Get the driveshaft from a junkyard and cut it myself or have it cut to fit? Stuff the Th400 in there? Rebuild the 2004R and use it? Or should I just wait until next year and concentrate on getting the 65 running this year?

[squirrel]

I would base the decision on what other rearends you have laying around. if you have one with 3.08s then go with the bop400, but build it if the hard parts in it are good. People will buy a complete chevy 400. And overdrives are for girls

[SpiderGearsMan]

A GOOD 455 WILL LAST WASTE TO A 700 OR 200 pretty quick

using an an adapter plate for the 700 ?

[Stich496]

well first of all..
a 200r4 is the same lenth as a th350 and powerslide.. a th400 with a 4" tail is longer than the other 3 listed so the shaft you have WILL NOT work with a 200r4 AND a th400.. pick one it's not BOTH/.
I'd get a yoke for the tranny and have the shaft built with a thick wall tube.. mine was 250.00 with ends and u joints /balanced..

it is rumored that a 84-88 b body shaft is the lenth you need

[Thumpin455]

Yeah I have an adapter plate for it. The 200 lasted quite a while with the highway gears in a heavy car. It was tired when I put it in and we drove it around for two years. When i went through it I had to do it in a storage unit without most of my tools and equipment, so I think I missed something or boogered a seal. First was nice and tight, second was the problem. Once it got into 3 or 4 it held up good. Funny thing was it was just as fast with a stock converter as the Th400 was with a 2000 stall L88 style converter.

The driveshaft does fit both 2004R and Th400, only need to swap the yoke. Its the only one I have had in the car since it went from a Muncie to an automatic and it has had both in it over the last ten years. The difference in the yoke makes up for the slight difference in length, its nearly a direct bolt in.



The only other rear I have for the GTO is a 2.93 Olds that was in it before, and it needs some new clutches before I can run it again. A couple of them are welded together from a loss of traction, then one wheel got some and the other didnt. Fun 1/8th mile smoke run. It is destined for one of the 65s, whichever one Dave wants to drive gets the highway gears.

The 700 has 4L65E gears and a beast shell in it, so it should live behind the 455 pretty well. Also it isnt going to get raced, just driven as much as I want, especially after the fuel barrel is full.

Im just trying to decide if I want to stuff the 400 in it or find another driveshaft. I suppose a call to the local junk yards with a length would be a good idea.

[SpiderGearsMan]

with a stock motor , the L88 style converter will slip more , slow ya down

The original L-88 converter is a full-sized unit (13 inches) that will provide a stall speed several hundred rpm higher than stock, while retaining maximum reliability. Due to the lack of original L-88 units, various converter rebuilders modify stock type 13-inch converters to work similarly to an L-88.

[Thumpin455]

Yeah its called a 400 high stall and you can get them at pretty much any trans shop for a little over $100. They let an engine with a bigger cam idle in traffic without creeping through the stop lights. These engines arent stock by any means, but they arent full on race machines that are cammed to start making power over 4000 either. They are set up to grunt like crazy between idle and 5000 then pull to 6000. Those converters work quite well, and I have run 11s with them in heavy cars and similar 455s.

I like the 2004R and 700R4 because of the lock up converter too. Eventually this engine will go in a Trans Am for mileage testing and it will keep the trans behind it. I wonder how fast I could get a TA to go in a standing mile with one of these engines and 2.41 gears.. Thats another thread.

[gearhead1218]

2004R can be built to handle the power.

[SpiderGearsMan]

I don't think they put autos in L88
but maybe in big cammed chevelles

[Stich496]

I don't think they put autos in L88
but maybe in big cammed chevelles

no auto L88
LS6 had a th400 , untill u blew it up..but lasted longer than a m21/22

[SpiderGearsMan]

they only made 250 L88s from 67-69
I did a lot of work on Artie's 68 L88 in 1993
he still has my 850dp on that milled plenum intake that MOFO ....

[SuperBuickGuy]

yes, but shipping would kill you... I haven't paid more than $50.00 for an A-body driveshaft and the last one was brand new.

how did you get a 700r4 to bolt up to a BOP pattern?

[squirrel]

I think he mentioned something about the adapter in post #5?

[SuperBuickGuy]

I think he mentioned something about the adapter in post #5?

yes but - why swap the guts in the T400 option? Maybe I'm just confused about everything - I'll be out selling my GM products to buy a Prius.

[squirrel]

I don't know....probably for the same reason I'd swap that guts out of that Caddy th400 I have into that Chevy case? I expect he knows what's in each of them, and would build the transmission appropriately.