GM TH400 vs 47-48 re

P

proctors garage

New member
Joined
Oct 22, 2011
Messages
159
Outside of the obvious lack of overdrive and lockup what thoughts do y'all have on this. My question is is the 400 as strong as the 47/48?I have been wondering this for a while. I know of a few guys on here that have run the 400 with some success but I don't know them personally to get any details so feel free to give me some ideas on the subject.
 
A 727 came in these trucks and can be made just as strong as you need it.


Sent via USPS 2 weeks ago
 
Some Pro-Mods use a 400 with first gear removed.

And they are MUCH stronger than anything Dodge has ever used.
 
IMO, yes the th400 is stronger in oem configuration. At some point in the strengthening/building process, the TH400 will get stronger/dollar spent and then at another point a little stronger they would run dollar/dollar. Ultimately, with the aftermarket case the TH400 is the strongest and you can get a brake. At $8,000 for a fully built 47, I'd be looking at an aftermarket manual box. Also, the converters are cheaper without the clutch. With that kind of weight, you'll need the lower first gear.

I'm talking out my butt a little here, but, I don't think you can get a brake in 47 or 48.

I bought the strongest powerglide you can buy and have learned that I can't use the trans brake and boost above 20lbs. I have yet to be hooked at a track, but, I'm guessing the 1st gear band will fail when I do. She's only making 650-700hp right now as well. I'm quickly learning that 1800 ft lb of torque is way more punishing than 2500hp from a gasser.

Again, JMHO
 
Many a times I left off the brake at 100# + boost. Had prob. 500+ passes leaving at 30+ lbs. Then another couple hundred leaving much softer in the beginning, still always 20# plus though. You don't get 1.09 60's from leaving soft and waiting around on boost to finally come in, you Have to have good parts and get after it.
 
You can get a trans brake for the 47rh/re. I have one.

$8k seems a little high for a good build on one of these. I've had the 47rh's built for my 12v and the Camaro for quite a bit less than that, including the 47re in my fiance's 24v.

Perhaps going full billet everything possible inside puts the cost up that high, but I wouldn't know because I haven't gone that route.
 
you Have to have good parts and get after it.
Click to expand...

Hey Stock600, I've got the best parts money can buy. I wonder if the TH400 reverse is stronger than the glide? I'm actually looking at the 2spd th400's right now. I have yet to see an HP rating.

You can get a trans brake for the 47rh/re. I have one.
Click to expand...

coool. I didn't know for sure, now I do. lol And yes, the $8,000 is full billet Suncoast tranny. My son is running a $2,000 47RH with a single disc converter and it's holding great.

Has anyone had any experience with the Lencodrive? I sent them an e-mail and I'm awaiting a reply.

Sorry to the OP for swinging this thing off course.
 
Bodacious said:
Hey Stock600, I've got the best parts money can buy. I wonder if the TH400 reverse is stronger than the glide? I'm actually looking at the 2spd th400's right now. I have yet to see an HP rating.



coool. I didn't know for sure, now I do. lol And yes, the $8,000 is full billet Suncoast tranny. My son is running a $2,000 47RH with a single disc converter and it's holding great.

Has anyone had any experience with the Lencodrive? I sent them an e-mail and I'm awaiting a reply.

Sorry to the OP for swinging this thing off course.
Click to expand...








I don't know what to tell ya besides I jumped in your thread very early on and tried to help you with free advise that was very proven. You went the direction that I did at first as well that failed me don't know what else to comment on. They failed for diff reasons but still failure. Mine was because I couldn't at the time get my convertor in it, if I could have... maybe then I would have found other problems, don't know. I do know the TH400 did me very well with my convertor. Do a search under my name, Ive beat that subject up more than I should. But it's all there for people to read in the future so no since on me talking it any more. Like I also said before, lots of great info here if you can sort through the crap to get to it
 
This is me just tossing the idea around but we are killing converters one right after the other one time might be the lockup clutch next maybe something in the fluid coupling like turbine fins deforming. I have been talking to a guy that builds a manual clutch drive for a 400 300m input and all. I know of a few guys doing this with 47/48 like seth and the scheid guys. So thats what I'm thinking about. As for overdrive we run a pretty tall gear and have rpm to spare. I also thought about putting the 47/48 overdrive section behind the 400. I talked to a clutch company today that builds a slipper style multi disc progresive locking clutch so in my mind I think it might work. Tranny guy also said we might build it for the 47/48 also but we've been through a 5 gallon bucket of 2nd gear bands too so thats kinda my reason for the 400 thought. and the thought of a trans brake that will hold gets me excited too.
 
Also I'm curious about what bell housing for the clutch say maybe john robinson is using. Maybe use one for a chevy and adapt it to cummins.
 
Check into a 4L80E, basically the same as a 400 and you will have O/D. They can handle a lot of power and you can make it a manual valvebody, so you won't need a computer to shift it. Just a thought.


Sent from my iPhone using Tapatalk
 
Tranny

Mr Proctor I'm not sure how a non lockup would work in yours at your weight. I think with a good convertor and a bunch of trial and error it would work. I do know you wouldn't brake **** everytime you go out. The lockup is a blessing and a curse! The little duce we are fighting a convertor problem but we will get it. Nothing is easy. It doesn't run fast like it should but it always runs and loads itself in the trailer under its own power. Bodacious I promise you that if you have the best stuff money can buy a glide will hold your power ALL DAY LONG!!!! The band and clutches hold WAY more power than you or I can put to them. It sounds like FTI just don't want to mess with it. You never did tell me what kind of pump pressure you have at 2000 rpm? Does your tranny have a stock type front pump or a aluminum pump? Your tranny should laugh at the power you little turbo and motor is giving it. That's not a slam on your motor at all! I'm just saying a single 75 or 80 with no nitrous should in no way hurt your tranny.
 
pratherjoe said:
Check into a 4L80E, basically the same as a 400 and you will have O/D. They can handle a lot of power and you can make it a manual valvebody, so you won't need a computer to shift it. Just a thought.


Sent from my iPhone using Tapatalk
Click to expand...

yeah I thought about 4L80 I know they are very similar to 400 just didn't know about availability of good race parts like the 400.

Sent from my C771 using Tapatalk 2
 
Stingpuller said:
Mr Proctor I'm not sure how a non lockup would work in yours at your weight. I think with a good convertor and a bunch of trial and error it would work. I do know you wouldn't brake **** everytime you go out. The lockup is a blessing and a curse! The little duce we are fighting a convertor problem but we will get it. Nothing is easy. It doesn't run fast like it should but it always runs and loads itself in the trailer under its own power. Bodacious I promise you that if you have the best stuff money can buy a glide will hold your power ALL DAY LONG!!!! The band and clutches hold WAY more power than you or I can put to them. It sounds like FTI just don't want to mess with it. You never did tell me what kind of pump pressure you have at 2000 rpm? Does your tranny have a stock type front pump or a aluminum pump? Your tranny should laugh at the power you little turbo and motor is giving it. That's not a slam on your motor at all! I'm just saying a single 75 or 80 with no nitrous should in no way hurt your tranny.
Click to expand...

the conversion from converter to clutch would enable lockup.It can be adjusted to lockup at different points like the ones top fuel cars use for example.

Sent from my C771 using Tapatalk 2
 
proctors garage said:
yeah I thought about 4L80 I know they are very similar to 400 just didn't know about availability of good race parts like the 400.

Sent from my C771 using Tapatalk 2
Click to expand...


You can get about the same parts. Clutch packs are basically the same, so you can put alto in everything. Transgo makes a full manual kit. You can by shafts and drums and heavy duty converters. Good luck


Sent from my iPhone using Tapatalk
 
proctors garage said:
This is me just tossing the idea around but we are killing converters one right after the other one time might be the lockup clutch next maybe something in the fluid coupling like turbine fins deforming. I have been talking to a guy that builds a manual clutch drive for a 400 300m input and all. I know of a few guys doing this with 47/48 like seth and the scheid guys. So thats what I'm thinking about. As for overdrive we run a pretty tall gear and have rpm to spare. I also thought about putting the 47/48 overdrive section behind the 400. I talked to a clutch company today that builds a slipper style multi disc progresive locking clutch so in my mind I think it might work. Tranny guy also said we might build it for the 47/48 also but we've been through a 5 gallon bucket of 2nd gear bands too so thats kinda my reason for the 400 thought. and the thought of a trans brake that will hold gets me excited too.
Click to expand...

This would be the best idea and route if you can make it happen, wont be as easy to stage and more maint. but hey it's worth giving up to have something repeatable and somewhat close to bullet proof. Not sure your ride or weight but if its a touch heavier like Jeff implied then Id def. leave it as a 3 spd and use the 2.10 first gear. Great idea to I'd like to see you make it happen, good luck.
 
proctors garage said:
the conversion from converter to clutch would enable lockup.It can be adjusted to lockup at different points like the ones top fuel cars use for example.

Sent from my C771 using Tapatalk 2
Click to expand...

Exactly. From the few guys that you mentioned that do run one, it still looks like their 60's stuffer pretty bad for their e.t. Having a true 1:1 lock up at speed is great but you still have to get one to leave on the tire hard. It's very doable with the clutch but also going to have its hard learning curve for sure. If you go that route I hope it works well and you fiqure it out. I think it would be a fast realiable setup in the end.

Straight cut gear 2.10 in the new SFI ATI case with the big input shaft for the win!
 
Last edited:
Clutch turbo

I run a clutch turbo in my nova back in the late 80's. It was fun to drive but I fought a leak out of the front pump/clutch drive. It was pretty violent on shifts but I had no clue how to set the clutch. It will need to slip on the shifts and I think all would be good. Get on yellowbullet they have a couple of treads about them. Someone on there still offers a kit for pretty cheap to build one. It sure would be fun to drive!
 
It didn't seem like the triple threat dmax had any luck with the th400.
 
You must log in or register to reply here.
Back
Top