T-Riv tranny

[sailor77]

What transmission is in the 85 T Riv? Also is it a lock up overdrive like the 200R4? Is it controled by vaccum or 12V input? Thanks

 

[Turbo Riviera]

If you have a overdrive trans, it is the TH-325-4L. It is a lockup and does take the 2004R converters. In fact, the internal guts of the trans share many of the same parts as a 2004R. Clutches, drums, converters, servo's etc.

 

[turbobooster]

mmm thats interesting would any of u happen to know if i can swap my 2004r and drop in the 700r4 wit no modifications? is this an ez swap ?i tried the trnasmission section but they dont seem to wanna help me out or just answer the question though id get something tips or info from u

 

[sailor77]

good, as long as it uses a 12v input I will be able to let the computer control the 700R4.
While I got you here. Is there any thing better or worse about the Riv 3.8 then the GN's? I am using the motor for a Hybrid

 

[TRiv]

Originally posted by sailor77

While I got you here. Is there any thing better or worse about the Riv 3.8 then the GN's? I am using the motor for a Hybrid

What kind of hybrid are you building? Doing same here, though not really hybrid, but using 85 T Riv motor, trans,axles,etc., also have a nice 85 T Riviera. The motor is same as 85 GN. Differences would be: * the turbo outlet points up and uses a U shaped pipe to direct turbo outlet to manifold *headers are different and are unique to the T Riv, and the crossover pipe is a bit small and routes up and over the TH325-4L trans, *the turbo hangs over the back of the motor, keep this in mind as could cause interference with firewall in a hybrid ( would'nt fit in a GN this way) *the oil pan is unique to the Riv for axle clearance, though the GN pan can be used in its place, and if you're chassis can use the GN pan probably should as it is a bit larger and is baffled, *the 84-5 T-Riv motor uses the older 83 down turbo cam. That's about it that I can think of. Do you still have the Riv trans?

 

[Turbo Riviera]

The oil return for the turbo is at the back of the engine instead of through the intake manifold like the hotair regals, or at the front like intercooled regals. Not sure about 85's, but my 84 is the 14 bolt engine which is supposed to have inferior metal in the casting to the intercooled block. Personally I haven't had ANY problems with it though. Mine still has all the original short block in it still including bearings. Only change is a camshaft to the entire motor. 226/220 Lunati and it runs well.

 

[sailor77]

I am pulling the motor and putting it in an 89 Jeep Wrangler that has the 4.2 I6 carbed. I don't think I will have clearance issues as I will be able to move the engine forward a little and use an elsectric fan. I will address the oil pan issues when I get there, but I don't see a problem there either.

I pretty much got it figured out. I am going to use the adapter plate for the BOP to chevy tranny (700R4). After that I will use an S10 transfer case (231c) and do a slip yoke eliminator (SYE) to allow for a longer rear driveshaft in the jeep. Tom Woods make both the SYE and custom drive shafts.
Advance adapters has the engine mounts for the 3.8 in to the wrangler. Now all I gotta figure out is the wiring mess, and fuel system that I am going to need.

Yes I still have the tranny, have the whole car actually. The car has 83K miles on it and is in perftect condition minus a banged up drivers door. It was a grandpa's car that was always garaged. No rust anywhere. If you are interested in some parts maybe we can do a trade or something. I paid $500 for the car so if I recoupe that $ I will be a happy camper.

 

[TRiv]

The oil pan should'nt be a problem, in fact the Riv pan may be an advantage for you depending on where your front axles are located in relation to the engine. If an 85 engine it should be the 20 bolt pan which is same as 85-7 GN motors so you have options. One other difference the Riv motor has is the motor mount, same bolt holes in the block so you can switch to GN/Regal mounts if needed.

Question on your trans/ transfer case, giving me a possible idea here, how long is the overall trans/transfer case assembly, measuring from bellhousing/ block surface to end of transfer case, and how about end of transfer case towards the front output shaft/yoke?

Could be interested in some parts here, I know of another board member who may also. If car is 85, the chance of the differential being a 3.36 is very remote but if it is I would be interested, the code on the decklid parts decal would be something like FW4 or if looking at the differential there is a tab when looking at the diff cover that will have a few numbers and letter stamped, should have an 'N' for 3.36 gear, 'M' would be 3.15 anything else would'nt matter.Would be interested in a rust free driver fender, dent free ( a ding or 2 ok) driver side rocker molding, motor mount bracket if you switch to GN, TURBOCHARGED 6 emblems if you are'nt going to use, Ttype and Riviera emblems if nice, probably some other stuff if I remember later, and I need to know what state you're in as I'll have to figure if any heavy stuff is worth shipping.

'Turbo Riviera' (Scott N.) did you keep the 84 Riv, just wondering?

 

[Turbo Riviera]

TRiv

Yep, I still have it... I never really tried to sell it that hard. I was having a "Buick" moment I think. You know the ones... Where everything Buick sucks! I'll probably keep it. I do need to sell my 11 sec '87 GN though. That will leave me with 2 hot airs.

 

[sailor77]

Thanks, I will send you a PM with my #. I am in Rhode Island.

 

[turbobooster]

hey sailor what do u mean by that 12v input? how do i know if i have one or not where i can i check to see or what other ways to know or find out ? im not to sure of what ur sayin not to familiar wit the terms yet but learning in the process thanx again

 

[sailor77]

12V input....

Ok here is the lesson you want to learn. The transmission sends inputs (mechanical) to the speedometer and VSS (Vehicle speed sensor). The VSS determines the speed of the car based on these inputs and sends signal to the computer. When the computer determines that the vehicle is in an overdrive conditon it locks the torque converter with a 12V signal. When the car slows down or the brake is applied the 12V signal is canceled and the Torque converter is allowed to unlock.

Since the 200R4 and the 700R4 are both GM overdrive transmissoins there should not be a problem with this. Here is the only place you may have a problem..
1) The 3.8 is a buick motor and such does not have the same transmission bolt patter as do most 700R4's. There are many sorces that sell BOP (Buick-Olds-Pontiac) Engine to Chevrolet tranny adapters. Very Easy

2) I am not sure, but make sure that the splines on the output shaft number the same as the drive shaft splines. Tne 700R4 is just slightly longer than the 200R4, so that should not be a problem.

Also, stock shifter, crossmember should work fine

 

[Drac0nic]

the early 700R4s did have the same splines as a TH-200, but they're not held in high regard honestly. The later ones had more splines, simple as a TC swap from the way I understand it.

 

[sailor77]

block heads crank
Turbo Riviera . 25520231 25518445 See 1978
FWD (Flat lifters) 25520043 25518445 25514267

I got these #'s off gnttype. The block is not the same as any of the regals and neither is the crank. Is that anything diff about the block? thanks

 

[Turbo Riviera]

The turbo oil return is drilled into the back of the lifter valley instead of down the intake manifold. That's the only difference I'm aware of.

 

[sailor77]

Does it have the roller cam or flat tap?

 

[Turbo Riviera]

It's a flat tappett... When I measured mine for national record teardown it measured .380 lift intake and .360 exhaust lift. Not sure what the duration is stock though. The car went 13.60's in my 3810 lb Riviera with a 1.86 60 foot on the stock motor including heads, cam, and turbo. Unless you're getting real serious about making ALOT of power, it's not a bad cam to use. It idles nice and gets decent gas mileage. My Riv got about 25 highway mpg when I drove it alot.

 

[sailor77]

well considering the jeep is about 1K lbs lighter that should not be a problem. Just inquiring for durability. I gotta figure out the wiring and VSS now as Caspers wants $600 for a harness. That is more than I paid for the car so I think not. LOL

 

[sailor77]

I noticed something today that I need to clarify...

On my Riv the Turbo is mounted rear of the engine. On some 84/85 regals I have seen it looks to be mounted over the intake manifold. Am I seeing this right? If so, would be possible for me to swap to this, thus gaining more firewall clearance? Thanks

 

[Turbo Riviera]

Absolutely, just use the '84-'85 turbo regal heders and turbo mounting brackets or fab your own. The intake manifold is exactly the same. Just plug the hole at the rear of the block and take the rubber plug out of the top of the intake manifold for your turbo drain.