TH400 tranny for drag racing?

stock600 said:
Not at first, I did break a Vasco and 300M input and twards the end had to go to the big areospace shaft and drum, the shaft had a greenish look to it. I also broke a set of hylical planets but no more failure after going to the straight cuts, I stayed with the 2.41, 1.41, ratio's. What have you decided to run, just curious....
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So after many passes untill you broke them, did they break or just twist. marage is supposed to be about 20-25% stronger than those metals at the same size. your car made a ton of TQ i see, what did it weight?

the 1" shaft is supposed to get about 20% better effiecency out of the convertor, because of the fluid flow. The bigger shafts take that a way, and have less effiecentcy because of the lack of fluid flow. See where im going...
 
Na, they both twisted and broke in 2 pieces. The vasco broke way out on the end just after the stator, leaving that little piece in the convertor it was tough to get out. The 300M piece broke up nearer the seal in a place that it looked like it shouldnt break, lol.

I noticed no diff. in stall speed or eff. after going to the new input/drum, they obviously made a change to the convertor but I noticed very little diff., but again this all is becuase of the size of the unit to begining with. Ive stated before my combo was all torque.... it made great HP also but I utilized all the torque I could by staying tight and getting a moderate sized charger lite damn early. Not the popular way I see but it worked for me, low 5.40's on just diesel was no sweat; just wished I could have had one more season to open the bottle and play with nitrous tuning with the car, there was so much potintial. One full season was a blast but you never learn a car and what it's All about in just one year
 
stock600 said:
Na, they both twisted and broke in 2 pieces. The vasco broke way out on the end just after the stator, leaving that little piece in the convertor it was tough to get out. The 300M piece broke up nearer the seal in a place that it looked like it shouldnt break, lol.

I noticed no diff. in stall speed or eff. after going to the new input/drum, they obviously made a change to the convertor but I noticed very little diff., but again this all is becuase of the size of the unit to begining with. Ive stated before my combo was all torque.... it made great HP also but I utilized all the torque I could by staying tight and getting a moderate sized charger lite damn early. Not the popular way I see but it worked for me, low 5.40's on just diesel was no sweat; just wished I could have had one more season to open the bottle and play with nitrous tuning with the car, there was so much potintial. One full season was a blast but you never learn a car and what it's All about in just one year
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how long did it take to break those shafts?

What did your ride weigh with you in it?

What size input did you end up with?


A year of testing for me would be nice, of course more is better. but im not patient.LOL
 
Not sure to just how many passes each had on them... I get a lot more passes in than many people. I took the car out one Sat. evening and made 22 passes before they shut the track that night, all 1/8th mile and nearly all 5.4x- 5.5x passes, not a failure one that night. The Vasco may have had 100 passes on it but that was the original shaft and the bulk of those were prob. high 5 to mid 6 second easy passes just learning to drive the car. The 300M maybe a couple hundred but they were all Hard launches and fast passes. And I prob. had another 100++ on the new shaft, i think it measures around 1.200 everyone calls it the 1 1/4 PM shaft. ~2800#
 
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DIESEL_POWER said:
how long did it take to break those shafts?

What did your ride weigh with you in it?

What size input did you end up with?


A year of testing for me would be nice, of course more is better. but im not patient.LOL
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I wished I had someone answering all these questions for me back then, I had to fiqure it all out the hard and expensive ways. Lot of Haters on this site, Im not one of them; I like to look back see what Ive learned and help out where I can, this is the kind of stuff that helps our sport grow. I had and tried many many more convertors in the glide but didnt mention all them at the time due to some of the convertor places read here and didnt want me to muddy thier name, and I did'nt out of respect to them, I had near a dozon convertor shops send me a 11" unit to try for nothing, just to see if thier's would work, I appreciated it from each of them very much and still do whether they worked or not. Each of thier goals was to built the tightest poss. 11" convertor, about 4k was it, I just ran right threw them. I knew after the first pass with a 13" convertor in the junky TH350 that it was the way to go, to bad none of the rest of the 350 was up to the task, but that lead me to the 400 which is once it had all the good parts in it. I wanted bad to make a 5 second pass in that 4500# truck but did'nt get it done in time before I get rid of it, did make several 6 'teen' passes though, felt fast in that truck.

Ryan
 
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stock600 said:
Not sure to just how many passes each had on them... I get a lot more passes in than many people. I took the car out one Sat. evening and made 22 passes before they shut the track that night, all 1/8th mile and nearly all 5.4x- 5.5x passes, not a failure one that night. The Vasco may have had 100 passes on it but that was the original shaft and the bulk of those were prob. high 5 to mid 6 second easy passes just learning to drive the car. The 300M maybe a couple hundred but they were all Hard launches and fast passes. And I prob. had another 100++ on the new shaft, i think it measures around 1.200 everyone calls it the 1 1/4 PM shaft. ~2800#
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Thats a lot of passes!! i would say that those shafts did quite well @ over 100 passes...and you weight 2800lbs too. Thanks
 
I'm in a conundrum myself on transmissions, I'm building a mud racing truck, weighs in at 4400 lbs, I don't use overdrive when racing, and not used lockup either. I'm lucky to get into 3rd before the end of the 100' pit. I am building a 650hp 12 valve for the truck and am looking at having to spend a ton of money building the 47re to handle the 1200 ft/lbs of torque. I'd much rather run a th400 and an np205 transfer case, but didn't think the th400 could be built to handle the torque. Any thoughts of building one for a mud truck? The only purpose of the truck is mud racing
 
Read the thread Stock600 posted...he has as much experience as anyone. I would say a TH400 should live in a 650 hp mud truck because there will always be a good deal of slip. Getting the converter right always seems like the hard part on diesels.
 
I remember suggesting something like that in your trans thread about a mud truck.
 
Lower said:
I remember suggesting something like that in your trans thread about a mud truck.
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Yeah, I remember you recommending building a th400 up for the truck. I've done alot of research on the 47re and what I need to do to it to build it up, and what I'm looking at is about 4500.00 worth of parts by the time you do a full rebuild, billet input shaft, torque converter, flexplate, front drum, etc.. And that is with me doing the building. I'll also need to rebuild the transfer case as well.

I've had quite a few friends that I know that mud race suggest swapping over to a th400 as well. To swap on the truck, I'd need a different trans brace, 2 new drive shafts, a transfer case and an adapter for the trans. I'm not looking at the initial cost to switch or build it this once, but the rebuild cost over time as well.
 
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