TH350 v TH400
Thread Starter
Burning Brakes
Joined: Jan 2010
Posts: 884
Likes: 84
From: New Boston, NH
TH350 v TH400
Is there any considerable difference? I have heard that the 400's extra weight saps some HP, but I really don't know enough about it to gauge the validity of that claim. I am wondering if there would be any advantage to replacing my non functioning 400 (75 L48) with a 350. If there is an advantage, how complicated would it be?
Thoughts?
Bryan
Thoughts?
Bryan
Burning Brakes
Joined: Jan 2007
Posts: 1,057
Likes: 4
From: Concord Calif
Is there any considerable difference? I have heard that the 400's extra weight saps some HP, but I really don't know enough about it to gauge the validity of that claim. I am wondering if there would be any advantage to replacing my non functioning 400 (75 L48) with a 350. If there is an advantage, how complicated would it be?
Thoughts?
Bryan
Thoughts?
Bryan
The 400 takes a bit more power to run, but in street form you most likely will see no difference, there is a gear ratio difference also but no big deal on a mild street car. I would just fix the 400 as that would be cheaper and cause you no changes to your car@ drive line, tail mounts and such)
Thread Starter
Burning Brakes
Joined: Jan 2010
Posts: 884
Likes: 84
From: New Boston, NH
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If you are going to replace the tranny anyway, the difference in costs between installing a 3-speed THM350 and a "Used & rebuilt" 700R4 is not that much different. And, when you get done, you get the added benefit of an overdrive gear and converter lockup in upper ranges.
Since you have to change it, NOW is the time to get the OD tranny. If you don't want to break the bank, buy a used 700R4 or 200R and have a reputable tranny shop in your area do the rebuild...much less than buying one from a vendor.
Since you have to change it, NOW is the time to get the OD tranny. If you don't want to break the bank, buy a used 700R4 or 200R and have a reputable tranny shop in your area do the rebuild...much less than buying one from a vendor.
Thread Starter
Burning Brakes
Joined: Jan 2010
Posts: 884
Likes: 84
From: New Boston, NH
I have been looking into the 200R since 7T1 mentioned it above. If it really is a direct fit or little mod install I can definitely see the benefit. I looked at bowtie and their prices seem pretty reasonable. Can anyone recommend anywhere else? I live in the DC area and getting a trans rebuilt around here costs an arm and a leg. It would be a better option to buy one already rebuilt. How involved is the transplant?
Racer
Joined: Mar 2003
Posts: 448
Likes: 21
From: Klein Texas
I don't think so. the 200R4 swaps with the TH350 easily but the TH400 has a larger output shaft yoke, electric kickdown and other minor differences.
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