If you've followed my rants, you know my original TH400 has nuked itself twice, the last time in a matter of weeks.
My plan is to get the cooler lines flushed, the converter flushed, and install a brand new tranny. Neither high-po tranny shop could ID what *caused* the failure (but it was obvious what was wrong both times- metal flakes and/or clutch material clogged the filter, causing line pressure to drop terribly during heavy load frying the trans).
The TH400 gets connected to a gear vendors (I should just sell the damn thing.. I never drive on the highway and my gas mileage bites anyway because 4000lb+loose converter+454..), but I don't think the gear vendors would affect who I buy the trans from.
The question is who?
I was rec'd dynamic transmissions of CT (not to be confused with the other dynamic) and I've heard good success with ATI and Hughes. If there are others I'm open to suggesstion as well. I just want this thing to shift well and last..
I will *not* be returning a core with this. The trans I have works well enough if you don't step on it, and its the original for the car. So...
The second question, and I asked this before, is full manual valvebody or auto/manual. I have a b&m ratchet type shifter (quicksilver? I forget, its in the garage hidden somewhere) that I am going to try to work into my console so it doesn't stick out like a sore thumb.
The car is 95% street, but say a "very high performance" effort. Lets just *say* (I know this is a highball estimate) that the engine makes 600hp/600ft-lbs (w/ dyno headers and no mufflers it made 580, with my headers, my x-pipe and my mufflers 565), both tests running with accessories.
Numbers don't matter all that much, I know, but I just don't want another tranny to decide to swallow parts of its own metal and then digest the clutch packs..
So.. I type too fast for anyones good..
Back to the basics: Who? (dynamic, ATI, hughes?)
And: Manual/Auto or Manual? (what are they key advantages/disadvantages here? Why would a shop steer me toward a full manual (non-reverse type), cost aside?

A tech/possibly owner at one shop said he thinks I would be less prone to breakage and more reliable all around with a manual VB. (I'm not sure if my ratchet shifter works with a manual VB, I'd have to check).
How much of a difference could this possibly make?
Its not like I mind pushing a lever to shift, but if I don't need it, then..?
Now, my conversation with one of the trans companies was a few months ago, but I wasn't ready to buy then. They said with my power level, I'd be less prone to breaking things with a manual VB. But I'm pretty sure Tom Baird runs a 540 in a 4100lb car (heavy like mine) with a manual/auto. I'm going to buy the trans sometime soon and get it in sometime between january and march.

All the prices at the trans I've looked at hover in the 800-1000 range, plus or minus some, I didn't ask about shipping though.

Sorry for the spray of words for such a simple question..

Matt

Why dont you email "transman" Steve Oldani. I bought a street/strip BTE TH400 from him. I am happy with it so far, it hasnt been tested at the strip yet due to some other issues. I also bought a torque converter from him as well. He answered all my questions, some of which were probably dumb :D
He is a great guy and he may be able to help you.

Check this out: There trannys come with that seperate bell housing and there not big money...mike http://www.racewithjw.com/

Wow.. Those JW's look like some serious units. I'll see what Steve has to say when I get back this evening and have time for some real email.

Thanks guys..

Matt

I'd either call Steve or Dynamic

Dynamic I might be able to save on shipping because I could drive down. I don't have a clue what truck freight to a terminal or my house(!) would be..
I'm leaning toward the auto/manual, even though the guy at dynamic suggested the full manual when I talked with him on the phone. I had to keep reminding him the car wasn't supercharged.. (the guy who put my cam in does mostly blower motors..)..

Matt

Give Mike a call at Trans Pro in Lansing IL. I know it's kind of a trip for you, but we've got a 700R4 holding up to 700 hp on nitrous right now through him, and he's got a wheelie pulling buick with a TH350 in it. He's just plain damn good with transmissions. The number is 708-895-0003.
Tell him you've heard good stuff, tell him your application and he'll do you right. I dont think it will be as expensive as those big name companies either.

Hope I can help,
Joe Phillips

Matt,

my Hughes broke after 3 1/2 seasons, rolled the intermediate sprag. My ATI burned up the clutches after 10 weeks.

I have yet to do anything about them. A guy in Jersey who does racer1320's trans is going to do my next one.

Originally posted by mc71454:
Matt,

my Hughes broke after 3 1/2 seasons, rolled the intermediate sprag. My ATI burned up the clutches after 10 weeks.

I have yet to do anything about them. A guy in Jersey who does racer1320's trans is going to do my next one. Why not just rebuild them yourself? With the help of Jacob S. and a couple of rebuild books I did mine with no problem. The only tetious part was removing/installing the spring packs in the forward/direct clutches. Installing the seals takes a little work. I installed mine with feeler gauges; you could by a seal installation tool for a few bucks. No real specialty tools are required. An air compressor is helpful to check seals for leaks as you're assembling. An outside mic or dial caliper is helpful if you want to mix and match steels to get a particular clearance. 125+ 10 second passes and no problems so far. I just put a new filter and gasket on while the engine is out. There was very little clutch material in the pan and everything looked great! Just a thought... graemlins/waving.gif

i took my th-400 to my neighborhood MR.TRANSMISSION and had them rebuild it including replacing the oem torque converter for about 800.00.i havent had a problem with it in two years of hard use.

I've had my TH400 rebuilt twice, the 2nd time by a guy with a very good reputation. The problem was he couldn't figure out *what* caused the failure, neither could the first guy. It was obvious what was wrong, but no one has been able to figure out why. Its the original tranny and I want to hold onto it for various reasons, so I am going to sideline it. I'm not really familiar with what could go wrong, but somewhere inside the trans is creating metal shavings that clog the filter & burn the clutches. No one could say where it was coming from, so I am just going to say its a lemon for high-intensity use and try a different unit. I've already spent near or close on rebuilds of this particular one on what it would cost, I don't see the point in another $400 rebuild or whatever it would cost just to have it fry 2 weeks into driving it.
I am probably going to buy one from dynamic in CT, and I am probably going to go with a auto/manual setup vs. the full manual despite what he says.. Although no one has really commented on that aspect yet...

Thanks Everyone..

Matt

And if you decide to dump the gear vendors you'll let me know, right? ;)

Joe, thanks for the tip in Lansing!!

sorry you cant find where the mysterious metal is coming from..that sucks!

The T400 out of my 67 Biscayne had the same problems. Rebuilt it myself and it shifted WAY too hard. Had a pro undo it, and now it looses 2nd frequently. No one can figure it out. I figure the case is out of spec or something.
BTW, its been in a 510" Camaro for around 5 years now. I don;t use an auto, but its jinxed, like yours.

Hughes makes a good unit off-the-shelf. I wouldnt resue the one you have, BTDT, and never got it right.

Matt, I'd suggest when you change it this time get the tranny and converter from the same people. Metal in the pan is not a normal occurrence, and spend whatever is neccessary to get the best parts available. We have had good luck with Turbo's from ATI. Steve Oldani could probably find out what is wrong with your current one. Doing second gear burnouts and then hooking while keeping your foot in the gas will kill any three speed Turbo, 350 or 400. Spinning then hooking = broken sprague. I know a kid that was spinning going around a corner when the tires suddenly hooked up, it broke the sprague immediately and he got to walk for a while. He was a lot smarter and a lot broker after that.

would a heavy duty sprag not stand up to the abuse?

If you a developing metal shavings, the "problem" should be easy to identify.

Large amounts of metal can only come from seveal area of the trans.

Bushings, pump gear, thrusts, or converter.

It sounds to me like you have been using the same converter through 2 faield transmissions and are still wanting to use it again...

Is the material magnetic or not?

If it is magnetic it is liekly pump or converter material.

If it is non-magnetic it is likely thrust, bushing, or possibly also converter material.

Also depends on what they shavings look like, big chunks or fine dust.

Occasionally you will get a bad case (rarely) but the problem doesn't appear as metal in the pan. It would typically be mysteriously failed clutches. If everything air checks good, pressures are good, etc, and you have a clutch pack failing, time to start really checking the case for cracks or crossleaks.

I would call Steve and get a trans AND a converter.

Or do it yourself and call Steve and get a kit AND a converter.

I would be willing to bet it is a converter related failure.

Jake,

Thanks for the input. Its more clutch material in the pan, but there is metal but I don't know how much is too much and I dumped it and replaced the filter so I can't run any of those tests you suggested on it... When the trans died the 1st time, I sent the converter out to be inspected. The converter company said it was fine. But, I ordered another converter (the one I had was sloppy) and installed that when I put the trans back in. So the trans has failed behind two different converters in the same manner.
I didn't know what to look for when I saw the crud the second time, but there was alot of friction material. I am always frying the friction material/clutch packs on the 2nd and 3rd gear.
This is why I think the trans case itself may be not in best working order. I don't know what to say at this point, except two trans guys have gone through it. The guy who went through it the 2nd time said he was almost sure it had to be the converter because he couldn't find anywhere in the trans where the metal bits/flakes/shavings/whatever had come from.
But the converter company said it was fine, but thats sort of a "black magic" type of thing, as I can't see inside it to see what the story actually is.
When I got the trans back from the 2nd rebuild the trans guy gave me a like zero-stall 12 or 13" loaner until I got my new converter.
I didn't run the car at the track with the loaner deal. The trans failed some time over the summer after I put the new converter in.
How hard would it be to detect a crack or crossleak? Its the original trans from the car, and was out of the car when I bought it, its probably been knocked around quite a bit.
I've spent quite a few bucks on rebuilds with good clutch materials and and this time around a fairbanks shift kit if that matters, but it died in the same manner.
When I give it a load of go pedal while doing 30-40 or whatever, the trans just slips and the engine revs to the moon and the car goes nowhere. Same thing happened twice, different converters.
As far as I can tell, from a steady acceleration, there isn't any "noticeable" slip, but I bet its slipping some, as I can't/don't launch hard at the track due to traction issues.
The best examples, like above, are when I stop, get going a decent speed, then drop the pedal to the floor and absolutely zip happens as far as forward motion goes, just hit the rev limiter and and feel stupid.
I originally attributed this to the kickdown switch, not knowing any better, thinking because the kickdown is designed for lower-rpm motors, that it was kicking down at 5000rpm and then zipping right to the 6800rpm pill in almost no time.
But when the same thing happened sans kickdown switch, I put two and two together and said, this is exactly what happened last time. I pulled the pan and there was all sorts of stuff in it, but the fluid itself looked fine (not dark, or funny smelling, or whatever).
So I'd hate to have this trans rebuilt again just to go through the same thing. The 2nd trans guy has a good rep and said he thought it was the converter, but the 2nd converter test ruled that out.
So I'm going to buy a new one from somewhere, looks like dynamic or steve, depending on freight costs.
So sorry for repeating myself so many times, but this is as much as i have to go on..
The thing that perplexes me is that the 2nd trans rebuilder said he was 90+% sure that the metal did not come from within the trans, and probably came from inside the converter.
A few months before, I had removed the converter to get it tightened up a little, and put it back in, but it was still bordering on pretty sloppy.
The new converter I bought is a 9.5" from the other dynamic (lupos) and it is a bit more efficent on the top end, but I might have to send it back to be restalled, but I can't tell for sure until I can get a close to dead hook.
My only clue right now is that whenever I shift above 5k rpm, the RPMs drop back to right around 5k, which is a bit high for my taste and the torque on my motor, which comes in at 3500 and the converter was intended to stall around 3800, but for all I know it might. I just don't think its the best sign when the RPMs barely change when you shift..

My conclusion at this point is to try a different TH400..
I don't think I had two bad converters, although the other stuff you talked about I'm not familiar with enough to comment on, but I suspect they are things a decent trans guy would have picked up on, right?

If you read this, thanks.. :D

And if you got this far down harold, the sprague (sprag?) has never broken.. its been alot more mysterious that that. I'm pretty easy on burnouts but I might want to look into the "proper" technique..

Matt

Harold - or someone.....this is probably totally basic, and I apologize for not knowing, but could you elaborate on second gear burnouts and then hooking while keeping your foot on the gas? I don't know what that means which means I might be doing it and not know it. Does it mean when you floor the car from a stop, you are supposed to take your foot off the gas as it hooks and then floor it again? THANKS

My only clue right now is that whenever I shift above 5k rpm, the RPMs drop back to right around 5k, which is a bit high for my taste and the torque on my motor, which comes in at 3500 and the converter was intended to stall around 3800, but for all I know it might. I just don't think its the best sign when the RPMs barely change when you shift.. How far above 5k are you shifting? Depending on stator combination, etc, I do not think it is terribly unusual for a 9.5" converter to have a high "shift recovery point". My 2600 stall 9.5" Precision industry converter in my daily driver only drops to 4000 or so on a 5400 rpm shift (Ford AOD), so if you are shifting above 6k, dropping to 5k is likely normal.

Search around on ls1tech.com forums for "shift recovery", or "shift extension". Lots of good tq converter discussion over there.

For example:

Yes, that is what a shift extension is described as and no you do not want the same shift extension as stock. You want it higher which keeps the motor in the stronger part of the power band for a longer period which results in the car "pulling" stronger. Picking a converter based on the dyno curve is good.

Examples:

My old converter - Yank Y3200 shifted at 6300 rpms, shift extension was 4200 rpms.

My new converter - TCI 3800 shifts at 6500 rpms, shift extension is 5150 rpms.

So when I run the quarter mile the only time the motor see less than 5150 rpms is from launch to the 1-2 shift (before the 1/8 mi), after that it's in the sweeter part of the powerband for most of the run which results in a better ET. This compared to a stock converter which spends a fair amount of the same run in the lower part of the powerband catching up.

I'm no expert, but these are obervations I've made over time based on my car's characteristics. I hope this helps.http://www.ls1tech.com/forums/showthread.php?t=227770&highlight=shift+extension

So here is an example of a 3800 stall speed converter dropping to 5150rpm when shifted at 6500.

Novadude-- thanks for that info! I had never heard of anything like that.
It happens whether I shift at 5400, 5900, or 6400.. it always drops to right around 5k.
So maybe the stall speed is dead on at 3800 and there is this shift recovery thing I had no clue about.

Thanks for the info! I'll be sure to read it tonight.


Matt

I had some problems with my T400 that might or might not be related. What mine did was limit RPM in low gear......sometimes. I wanted to shift at 6500, but from time to time the car would nose over at 6000.
A couple of friends suggested that it was the trans. And told me when I took it apart, I'd find burned high gear clutches.
Damned if they weren't right!
The high gear clutches were fried....still working, but fried.
Turns out that unde rht eright circumstances, the trans was applying high gear (partially) and low gear at the same time.
I removed the B&M shift kit and went to a Trans-Go -3 and the problem was solved.
I guess the B&M kit used such high line pressure that it caused a leak in the Valve Body that caused this problem. The Trans-Go kit doesn't do things the way B&M does, hence no more problem.
BTW....an internal passage leak can do the same sort of thing, and how the hell would you ever find it?
I have always rebuilt my own transmissions. They really aren't all that hard. The B&M rebuild instructions have been invaluable, because they break it all down into modules if you will, and as long as you work on one module at a time, it's pretty simple.
There may be some other things for you to consider.
Crank end play will wreak havoc with the torque converter....and vice versa. So check that.
Also, and this is a wierd one, .......if the engine can move rearward......while the driveshaft is moving forward.....the rear yoke has no room to move any further and something has to wear. Another thing to check.
And lastly, if you use solid mounts at the trans and engine, and the chassis flexes....the trans has to take the brunt of it, and maybe things inside the trans bind up.

Good luck, I can sympathise.

And BTW....before you crawl under to remove the trans.......get 2 quarts of ATF. Squirt one under the car on the floor, and dump the second in your hair and all over your coveralls. It's going to end up that way anyway....so get a head start. Besides, it makes it easier to slide under tha car!
Ron

And BTW....before you crawl under to remove the trans.......get 2 quarts of ATF. Squirt one under the car on the floor, and dump the second in your hair and all over your coveralls. It's going to end up that way anyway....so get a head start. Besides, it makes it easier to slide under tha car!
:D :D Something tells me you've swapped transmissions before! ;)

What makes it even more fun for me is that my pan has no drain plug.. (I bought a new one though), so, you just have to unbolt it and wait for the avalanche..
I don't know what exactly the difference is b/w the NAPA oil absorbent stuff (very light for its size) vs like generic kitty litter, but the napa stuff works great.. except when you are trying to wash it out of your hair..

Heh..

Matt

You Still Have Hair? Lucky You graemlins/hurray.gif

In 1970 I had a 64 Malibu that had a basically stock 327-275horse with a 4 speed and 3.31 12 bolt. I worked at a real good speed shop and decided to build a street racer.
I bought a GM crate LT-1 short block, bought the heads,intake, cam, valvetrain, and whole top of the engine from a nationally known national record holding F/MP racecar. I put all of this together and changed the gears to 4.88.
When the shop owner and I took it out for a test late one night, man was I disappointed. Going from a roll about 15mph in 1st gear, I matted it. The car made no forward progress and instantly hummed 8000rpm. I shifted into 2nd, same thing. Same for 3rd. So, we figure the clutch went away. We replaced the clutch with a really stout counterweighted Long style plate and all race parts.
Took it back out and same thing. We tried 3 more times. Then we realized, when I turned around to go back to start again, there's BLACK MARKS all over the road!
Turns out there wasn't a damn thing wrong with the clutch. It would blow the street tires off at anything under 40mph in 3rd gear!
I put on a set of 7" slicks and the problem eased up alot.

Could you be having the same problem?

Randy

Skier_bob, When doing a burnout, after they put down the water, start in low, shift into second then shift into high to get the tire speed up. When you feel the slicks start to catch up and try to push the car (get your foot OFF the gas). This will save the sprag. Any time the car spins hard the sprag takes a beating so being off the power minimizes the abuse on the transmission. My son broke three, two Turbo 400s and one 350, before he learned the correct burnout procedure. If you have street tires any spinning then hooking will eventually cause the same thing. And to the guy who asked about the heavy duty sprags they will last longer but eventually they will break also.

Originally posted by Harold Sutton:
Skier_bob, When doing a burnout, after they put down the water, start in low, shift into second then shift into high to get the tire speed up. When you feel the slicks start to catch up and try to push the car (get your foot OFF the gas). This will save the sprag. Any time the car spins hard the sprag takes a beating so being off the power minimizes the abuse on the transmission. My son broke three, two Turbo 400s and one 350, before he learned the correct burnout procedure. If you have street tires any spinning then hooking will eventually cause the same thing. And to the guy who asked about the heavy duty sprags they will last longer but eventually they will break also. I think the burnout procedure you use depends on a number of different factors. I can tell you from my own experience that the only time I ever busted a sprag in a 400 was doing exactly what you describe above. Are you sitting in the water box when you're shifting from low, second and high? If so, that might be ok. However, I can tell you with a high level of certainty that if you're driving through the water and beyond the box to do your burnout then your asking for trouble shifting gears in the burnout. I wack the gas as I'm pulling through the water box. I then pull ahead of the water box 5'-10'. I put the car in 2nd gear and engage the line lock. I bring the RPMs up to about 5,500-6,000 and look for smoke. Depending upon the track temperature I will wait 3-5 seconds and power out of the burnout in second gear. I let off the gas just before the tires bite. This procedure has worked well for me for over 300 passes. YMMV :D

Hey Ken,

You are right about building my own trans..just have to find the time and patience...I do the same burnout procedure as you do...my first sprag issue was after 3 1/2 seasons of hard racing.

harold, kjett - thanks....I have much to learn!

Try Chris at CKPerformance.com

Sorry if I repeat what others said, I didn't read through all the posts..but...I have had very good luck with ATI T-400's. Very reasonable price for what you will need and I abuse mine pretty good :D . One thing to watch is on the manual valve body you don't want to be downshifting it, if most of you driving will be on the street it may be a concern. Hope this helps

I've had the same problem twice with a th400 and high gear clutches,too much torque with too high of rear gears maybe? dunno :confused: I got about 3 months worth of racing the first time,went back thru it and the clutches started burning again about 3 months later,didnt get to the slipping part the second time,just had a th350 rebuilt and put it back in there temporarily,not sure how long it will last behind the new bullet.

We don't have ANY trouble with third gear clutches in TH400's. My buddy's 3600lb camaro ran over 200 9.40 passes one year and about 100 the following year, decided to check it out, and the clutches were in very good shape so he put them back in and ran it some more. Those were the cheap Borg Warner clutches also.

He says the secret is how he sets up the pump, the right clutch pack clearance, and to add a clutch or two by machining down the aluminum piston. And as I've said before, no 1st gear in the burnout box PERIOD - use third - and making sure to ease off the throttle when you come out of the box.

This time we are both going to be making more horsepower so we are going to try the Coan billet direct drum with ultimate sprague. An expensive touch but Coan says that if you are much over 1200hp you need it.

First, Get a B&M trans pan plug kit. Then next time you have your pan off, drill the 1/2" hole and bolt in the 3 peice drain plug kit. It is worth the $7.

Your overdrive with a loose converter is definately a problem if you use it. If you are cruising at a low RPM and your convertor is slipping it will get hot really fast and burn your fluid and degrade the clutch material. A standard 10" 3500 or 4000 stall that sells for $350 is what I'm referring to as not working. My buddy burned up his T-400 twice before spending some serious cash on a good convertor. You really need a tight 8 or 9" convertor for lower rpm cruising with overdrive. ATI, Coan and others can build you one but a good convertor is not cheap, expect to pay $750 to $900 for one.
His fluid would always smell burnt even with his large trans cooler.

Originally posted by 66 283:
We don't have ANY trouble with third gear clutches in TH400's. My buddy's 3600lb camaro ran over 200 9.40 passes one year and about 100 the following year, decided to check it out, and the clutches were in very good shape so he put them back in and ran it some more. Those were the cheap Borg Warner clutches also.

He says the secret is how he sets up the pump, the right clutch pack clearance, and to add a clutch or two by machining down the aluminum piston. And there "SHOULDN'T" be any problems with the directs on a TH400 that is properly built.
Bob's trans is one of mine.

We freshened it because he was getting a weak third shift. Clutches were browned as expected.
I bumped up line pressure, drilled feed holes a little bigger.

Nothing glaringly obvious as to cause.

If you have decent line, heavy direct clutch return springs, dual feed the clutch, you will almost never have problems.

Also a smooth tan Borg Warner "cheap" clutch is among the best you can use. Stock replacements for a 4L80-E...
Transgo says to re-use the stock ones if they are good....
I've seen the stock clutches work in 1400+ HP applications.

Bob's is an odd deal.. I do some special things to the pump to get nice tight clearances and no crossleaks. I also do some stuff to the direct clutch circuit to prevent pressure being bled off.

At his previous or even current level, he "shouldn't" be having problems.

As I understand it hasn't failed, it was still operating fine, but the fluid smelled burnt. That could be anything... Old fluid in the converter, directs going again, some other friction...

However,
I don't like to "throw in frictions" and hope for the best. If it does indeed have an issue, it needs to be gone over with a fine tooth comb.

I suspect a case problem but that could be difficult to find so next iteration will be a whole new unit...

By the way Bob,
I have the kit in hand, need to round up a core.

Originally posted by Jp-15:
Give Mike a call at Trans Pro in Lansing IL. I know it's kind of a trip for you, but we've got a 700R4 holding up to 700 hp on nitrous right now through him, and he's got a wheelie pulling buick with a TH350 in it. He's just plain damn good with transmissions. The number is 708-895-0003.
Tell him you've heard good stuff, tell him your application and he'll do you right. I dont think it will be as expensive as those big name companies either.

Hope I can help,
Joe Phillips i have a trans pro build 400 4 years no problem

Originally posted by jakeshoe:
Also a smooth tan Borg Warner "cheap" clutch is among the best you can use. Stock replacements for a 4L80-E...
Transgo says to re-use the stock ones if they are good.... I've seen the stock clutches work in 1400+ HP applications.

...I don't like to "throw in frictions" and hope for the best. If it does indeed have an issue, it needs to be gone over with a fine tooth comb.
I don't build 'em I just watch LOL. We tried the expensive Red Alto clutches once and couldn't tell the difference from the BW so we run the cheaper BW's now.

He doesn't just "throw in frictions" and hope for the best. If it is a high power application, why wouldn't you add clutches? I guess Coan and Mike's transmission are wrong for doing this in their Ultimate 400's.

My buddy is not a "professional" tranny builder, he only has a couple of feet of his work bench dedicated to it, but he has probably a dozen 400's out there in our group of friends that see 1000+ horsepower on the street and he hasn't had a failure so this ain't rocket science! They are a strong transmission to begin with so they don't need much.

Maybe it's because it's his hobby and not his profession and that he's doing it for friends that he can afford the time for the smallest details and has been lucky so far.

Nothing wrong with adding clutches.

You have to be careful though or you will run them off the end of the forward clutch hub.

You also do not want to get the steels too thin. They are the heatsink for the whole deal.

I've ran 6 clutch directs to 1400 HP.... So it is also not a necessity in most applications.

I have a 4 clutch direct in a TH350 to 600 HP...
over 2 yrs now of street and strip.

my family owns a tranny shop, and if your two tranny builders could'nt rebuild a turbo 400 i would really question there ability's! and these guy's dont guaruntee there work?

if you have any questions i'd be happy to help?


chris

Let me know Jake, weather permitting I might get a time run or two next sunday,at least get an idea of what its going to do before I get the rollbar in it. They dropped the e.t. on rollbars to 11.49,,,but I think I might beat that by a little bit.

dp again :(

Hey 66_283, what kind of line pressures does your buddy set up in your 400's? My new one is supposed to have between 260-270 psi. We were running around 220 on the last rebuild.

505Nova, I do not know - I will ask him next time I talk to him. He's not an expert - just trial and error and good luck so far.

Originally posted by 505Nova:
Hey 66_283, what kind of line pressures does your buddy set up in your 400's? My new one is supposed to have between 260-270 psi. We were running around 220 on the last rebuild. I would avoid running anything over 250 psi.
You can blow the splines out of the case if you get pressures too high.

If you dual feed the directs, anything much above 250 should almost never be necessary.

All TH400 transbrakes, and most manual valve bodies will have you dual feed.

Was it failing at 220?

Yes, we were having problems keeping clutches in it at 220 psi. He made a lot of changes to the case and passages in it, now has a modified hipster pro-tree brake. It's also got a girdle like thing to fix the weak area at the bottom of the case lugs if that's what you're talking about. I'm pretty confident it will work good now, my trans guy said there was a lot wrong in the way it was setup that last time. He said it should go two seasons without a hitch now.

Hi John, I think your present tranny guy will have your transmission problems cured. I also hear really good things about their bolt together Torque converters and think we'll try this coming season. I guess i'll probably sell the T/S "Big Dog" converter.

Don't know if this was mentioned or if this will help, but I have always been a fan of the inline magnetic filters!

Nah, you guys don't need one of those converters, just leave the same one in it for a few races give some us other guys a chance for a while...LOL Hey there's one of sale on the MAKO board, good price too.