Rebuild my 200r4 or buy a th400

[TurboJames]

as question says, im in a tough decision. If my trans gets rebuilt i have to get it done in US, and will cost quite a bit more. I can pick up a slightly built, shift kit servos etc. For 400$. What are the pros and cons?
I have a built 4.1 je pistons roller cam alky.. Probably 10s this year.

 

[whitehot1]

There are lots of opinions on this subject. You could do a search and see many threads about it. It really comes down to how you drive the car,highway,in town,street/strip,etc.

For me it was easy to decide because i don't drive the car out of town so no highway use at all. For that reason i went with a Th400 from TCI. It cost about half of what a built 200r4 would. I haven't seen any cons of doing the conversion to the Th400. Pros are the Th400 doesn't break,more money in my pocket,If needed i could send the transmission back to TCI and have them rebuild it for a small fee compared to what i paid for it, or i could have it done locally since it doesn't take a specialist to do them unlike the 200r4 which there are only a hand full in the country who people trust to do them.

 

[nat86]

CK Performance turbo 400 $2000 rated for 1200 horses with transbrake that is the path I chose.but just like Whitehot1 said I to only drive in town

Sent from my SM-N910T using Tapatalk

 

[Wahoo]

You would need to get a converter right? Cant use the stock one from the 2004r?

Also need to shorten the driveshaft

 

[Wahoo]

And fab up the shifter linkage.

And modify/lower the fluid pressure?

So not super simple.

 

[Wahoo]

Also gotta do something with the transmission crossmember/mount?

Sorry im contemplating this as well.

 

[bison]

I would plan on spending $$2500-3500 just to get into a transmission and converter that can live at that level with no extras. If you switch to a th400 you typically would be using a rev manual vb and typically would be better off with a good ratcheting shifter which would be extra $$$. The th400 is a quicker trans than the 200-4R in low 10 or faster cars also. Properly built and installed 10 sec 200-4r is typically $2500-3000 installed with supplied core. This doesn't include replacing pumps and drums if your trans needs them.


Sent from my iPhone using Tapatalk

 

[bison]

And fab up the shifter linkage.

And modify/lower the fluid pressure?

So not super simple.

This can be done with the stock shifter with a little work. You wouldn't be lowering pressure. You're raising it on a high Perfomance unit


Sent from my iPhone using Tapatalk

 

[bison]

Also gotta do something with the transmission crossmember/mount?

Sorry im contemplating this as well.

HR parts N stuff has an easy solution to this and yes it's an extra expense. Additionally the cooler lines typically will need to be tweaked to work with the TH400. All simple stuff for a do it yourself job but will be a few hundred more to pay a shop


Sent from my iPhone using Tapatalk

 

[Wahoo]

This can be done with the stock shifter with a little work. You wouldn't be lowering pressure. You're raising it on a high Perfomance unit


Sent from my iPhone using Tapatalk

I thought the th400 fluid pressure can push the converter towards the engine and take out the thurst bearing unless its modified?

 

[bison]

I thought the th400 fluid pressure can push the converter towards the engine and take out the thurst bearing unless its modified?

Only In a non modulated setup with the wrong orificing. If someone is relying on another to build a trans for a 10 sec car it should be expected that they know what to do to prevent overcharging the converter. It was covered in detail here in the past. You don't reduce line to prevent overcharging. You restrict oil to that circuit to get the charge where it's happy. It's a waste of time to even ponder for most since they will only speculate they have a charge pressure problem when they take a thrust bearing out. Seen plenty of thrust failures where the charge pressure was not the problem!


Sent from my iPhone using Tapatalk

 

[Wahoo]

Only In a non modulated setup with the wrong orificing. If someone is relying on another to build a trans for a 10 sec car it should be expected that they know what to do to prevent overcharging the converter. It was covered in detail here in the past. You don't reduce line to prevent overcharging. You restrict oil to that circuit to get the charge where it's happy. It's a waste of time to even ponder for most since they will only speculate they have a charge pressure problem when they take a thrust bearing out. Seen plenty of thrust failures where the charge pressure was not the problem!


Sent from my iPhone using Tapatalk

So youre talking about the check balls/valve body?

I was thinking about picking up a stock th400 and buying a basic rebuild kit more racing oriented(clutches), that comes with a shift kit, and calling it a day.

Id imagine that would be cheap and id be good til 11s or even 10 second power?

 

[bison]

So youre talking about the check balls/valve body?

I was thinking about picking up a stock th400 and buying a basic rebuild kit more racing oriented(clutches), that comes with a shift kit, and calling it a day.

Id imagine that would be cheap and id be good til 11s or even 10 second power?

It won't matter unless you get rid of the modulated oil and run constant pressure.


Sent from my iPhone using Tapatalk

 

[Wahoo]

It won't matter unless you get rid of the modulated oil and run constant pressure.


Sent from my iPhone using Tapatalk

I dont know what that means lol sorry im a tranny noob!

How is that accomplished?

 

[Steve]

I think the choice between a 200r4 and turbo 400 comes down to how you use the car. There are some desireable advantages to a turbo 400 but the lack of overdrive is the main downside. If you don't drive you car on the highway much or ever a turbo 400 is a good choice but if you spend some time out on the highway the 200r4 might be a better choice. I switched a T Type over to a turbo 400 some years back and I was unhappy with the lack of overdrive. I ended up adding a Gearvendor overdrive to the 400 but of course that is very spendy. If you go from a 200r4 with lock up converter to a 400 you are looking at about 1100-1200rpms difference at 70. I am considering swapping my current GN over to a 4L80E to get the more heavy duty platform with overdrive.

 

[robzombie]

I think the choice between a 200r4 and turbo 400 comes down to how you use the car. There are some desireable advantages to a turbo 400 but the lack of overdrive is the main downside. If you don't drive you car on the highway much or ever a turbo 400 is a good choice but if you spend some time out on the highway the 200r4 might be a better choice. I switched a T Type over to a turbo 400 some years back and I was unhappy with the lack of overdrive. I ended up adding a Gearvendor overdrive to the 400 but of course that is very spendy. If you go from a 200r4 with lock up converter to a 400 you are looking at about 1100-1200rpms difference at 70. I am considering swapping my current GN over to a 4L80E to get the more heavy duty platform with overdrive.

Which is just a TH400 with OD and also very spendy as you put it.

Like said by others, if it's a ten second or slower car that is driven a 2004R is the way to go for most.

 

[Steve]

Which is just a TH400 with OD and also very spendy as you put it.

Like said by others, if it's a ten second or slower car that is driven a 2004R is the way to go for most.

Actually if you are starting from scratch a 4L80E and a properly built 200R4 are very close to the same price. The reason they are similar in price is because the 4L80E requires very few upgraded parts to handle up 700 horsepower. My LSx car has a 4L80E with a $90 sprag, and $189 input shaft and it run's 9's and I have less than $2k in the transmission including buying the 4L80E core. Even with buying a $500 shift computer for a turbo Buick its in the same price range as a qaulity 200R4. I am not opposed to a 200R4 and I have had good luck with them in turbo Buicks for over 20 years but I do like the idea having the extra strength of the 4l80E.