Alex72cutty

I have a TH350 trans and was looking for something with an extra gear. Any advice would be helpful.

coppercutlass

The th400 is a 3 speed just like the th350 but it actually takes more power to turn it since it has more mass and heavier hd. components.

Alex72cutty

Oh, didn't know that. Thanks!

johnnyjaws

its a much stronger trans useuly put behind a big block but will bolt right up to a small block ur 350 trans can handle a lot of power.!

johnnyjaws

if u want a extra gear put in a 200 r4 they have a over drive in them

Alex72cutty

Yea, I thought about that too. Seems like I would have to find someone that has good knowledge of the 200r4 due to problems others have talked about.

coppercutlass

The th350 has it's weak points anything above 400 hp 450 tops I would start addressing the weak spots. The 200r4 will cost a lot more to handle any power and live.

Alex72cutty

I just had my engine rebuild and should get around 400-425hp. I've heard that overdrive would be better on the engine that is the reason why I would go with 200r4. What can I do to the Th350 to make it better?

coppercutlass

intermediate sprag race is weak and the center support are the 2 things most guys have said to upgrade . You can use the center support from a 700r4 and it will have more strength in that area.

Alex72cutty

Ok

70cutty

Look into gear vendors overdrive unit. It's not a bad alternative for OD. It bolts up to the th-350. I have not heard anything bad about them.

joe_padavano

While this is true, the 200-4R has two advantages over the TH350 (or TH400). The first is the obvious 0.68:1 overdrive fourth. The second is the steeper first gear (2.74:1 vs 2.52:1 in a TH350). Together I think this makes it worth the cost of a properly built 200-4R. As for the GV overdrive, a complete installation will cost at least as much as a built 200-4R, and likely more when you add in the cost of a custom driveshaft, possible floorpan mods, and other required changes. Also, the GV only gives you the overdrive, not the benefit of a steeper first gear for improvements off the line.

coppercutlass

The 200r4 does have that advantage of the steeper first gear and overdrive. I personally would do the GV unit simply because its been a proven unit that can handle the power. You build a good th350 or th400 which is bullet proof then add a good od. unit ad you have nothing to worry about. I would probably be a little un easy about the 200r4 since I have read about guys who have built them and they still failed which is the nature of the beast if you drag race and abuse it but the life expectancy of a th400 is much longer so to speak in relatively stock form and the th350 has limited life expectancy with no mods.

matt69olds

Since your in the Dallas area look at Jakes Performance. He has the 2004r figured out. He also builds cusom converters.

jag1886

This is the answer all you need is someone that is an expert with this transmission. If you want to know everything there is to know about 2004R go to the Buick Grand National sights, those boys have it figured out.

Alex72cutty

Will do Thanks!!

Alex72cutty

Have been on the site for the past couple of days. Thanks

5998DownUnder

Tony Lombardi of ROSS RACING ENGINES, Niles Ohio deals with Oldsmobile engines and transmission. He has some quality trans adapters there.
He is a member here.


John
(From Australia).

TexasT

You say Dallas, there is a guy that does a lot of Buick guys trans out towards rockwall. Those who have his work seem to like it.