Intrepid transaxle/Buick V6

[TRiv]

Does anyone have any experience with the performance of the Dodge 4 speed automatic transaxles used in the Intrepids/Concordes? Are they reliable and can they handle horsepower increases (2002 police Intrepid V6 245HP) and up? I am looking into mounting Buick turbo V6 to a transaxle for mid engine mounting, currently planned to use TH325 4L, maybe TH425 , but would rather use an automatic transaxle that can be mounted more conventionally in a mid engine design. The newer Dodge 4 speed autos looks like a possibility, of course wether it can be adapted is anouther story, but before I go down that road need to know what auto transaxles would work best with the Buick engine. Again I am looking for anyone that has experience good or bad with the Dodge transaxle, also the newer version called autostick.

 

[scottyb]

Aside from the mega-headache from cross-manufacturers, those I have spoken to in fleet leasing say the Intrepid, etc (fwd Dodge) transmission is JUNK. From more than one independent source.

 

[SuperSix]

WHy not an Olds Toronado transaxle?

 

[TRiv]

I do have a Riviera TH325 4L to use, and know of a few TH425 Toronado tranaxles available to use, just looking for last minute options to make the mid engine set up more conventional. As of now the plan is to use the either GM transmission with turbo V6 mounted in car backwards (pulleys facing rear) and differential clocked 180 degrees, it looks a bit odd that way, and motor is mounted more left in car , but will work (Chevy did the same in 1968 prototype mid engine Corvette) for best weight distribution. Also looking into possibility of Audi Porsche automatic transaxle. Whatever will work best with the Buick turbo V6,, and most agree that a 4 speed automatic with approx. 3.42 gears works best, so I am following that advice. Unless an audi ,Porsche, Dodge or some other auto transaxle will work, the TH 325/425 trans will be it.

 

[SuperSix]

I wonder if the import units can handle even a mild TR motor. I would also imaging mating the import parts to the Buick might be a bit of a chore as well.

 

[GNVAIR]

Take it from someone who works in the fleet leasing industry.......STAY AWAY FROM THE INTREPID TRANS AXLE!!
Bad, bad news!

 

[blackbuick87]

Not too many transaxles that can handle 400-500 lb/ft of torque.

Toronado or Riv would be the way to go, and make sure you get a couple spares

 

[SuperSix]

Originally posted by blackbuick87
Not too many transaxles that can handle 400-500 lb/ft of torque.

Toronado or Riv would be the way to go, and make sure you get a couple spares

That's my line of thinking..

 

[steve hughes]

Talk to Lonnie Diers. He builds trannies for front wheel drives and everything else. He knows what it takes to make one hold up.

Extreme Automatics
513-226-1315

 

[turbofish38]

Hi TRiv, Nice to talk to you again. One thought on all these late model trans axles. I'm no expert but isn't the Intrepid electronic controlled? If that doesn't put a wrench in your plans maybe a 4T80E from a Cadillac Northstar or even a 4T65E from a L67 supercharged 3800 might work for you. The bolt patterns are different but maybe you can rig an adapter. There is also a lot of HD parts devolped over the last year for the 4T65E. Just check out the 3800 Supercharged boards. Talk to you later. Eric Fisher

 

[GNVAIR]

The best people to ask are some of the V8 Corvair guys.
They can tell you what transaxles work and which ones wont work. Many options out there!
You first have to specify how the engine with be mounted and how much room you have to play with.
If it is longitude then the following will work:
TH425 or TH3254L (82-85 Toro. Riv, Eldo)
4L60E from a 97-2003 Corvette (just use an F body bellhousing)
Porsche 911 or 911 turbo transaxle (the turbo transaxle is good for over 900 horses!)
ZF 5speed (like the Pantera uses)
Renault 5 speed (another transaxle)
Corvair transaxles
Powerglide with a Corvair differential
727 torqflite with a Corvair differential
If mounted transversely, then the 4T80E would be the best bet.
Remember that if you use an electronic transmission you will need some sort of control unit for it. Make sure your trans has one offered for it.
Go to www.v8corvair.com for some ideas. Some of those guys are very creative

 

[TRiv]

Thanks everyone for the input, at this point the Dodge transaxles can stay in Dodges ,to bad, the layout was perfect, were 4 speed auto, and good gear ratios for the Buick. I for sure am mounting engine/trans longitudinally in front of rear axles so only a few automatic trans choices left, Audi, Porsche and th325/425. In making final choice again, looking for durability and best gearing ratios and speeds to work best with the Buick turbo 6. I know the th325 will work but is somewhat weak, especially the chain drive, the 425 is almost indisructable but is similar to the turbo400 and there seems to be a big division on the board here about using the turbo 400 for a street GN/T type, but the heavy duty chain plus the 12 bolt differential would be best, of course the 425 is only a 3 speed. As for the Audi/Porsche automatic transaxles I should look around for more info on durability, maybe anouther post, again they have final drive ratios close to the Buick 3.42 + 3 speeds, point here is trying to stay as close as possible to what has worked for most here in the way of trans (automatic of course) gear ratios and durablity, but one difference mid engine. Any thoughts, especially on the 425?

 

[blackbuick87]

Only reason people curse the TH400 is because it is heavy and there is no overdrive. As lone as you are not going cross country the 425 should be fine