Th400 First drive impression.
What shifter do you have? You can wire the trans brake into the reverse light switch and get reverse, but I would use a toggle or something to shut it off at the track so if you go into neutral on the big end you don't accidently get reverse
My vote is a 35 spline 9 inch!
My vote is a 35 spline 9 inch!
I used to throw the shifter into 2nd to get it to freewheel like it is in neutral on the big end. However, I have since changed my driving habits as this is a big no no and could cause the drum to explode and come through the case and floor board. The experts say you must leave it in 3rd gear and engine brake on the big end unless you have the special shift pattern vb/shifter. Also, the trans experts say to never downshift into first or second while the vehicle is moving as this is the equivalent to neutral dropping the trans.
BTW, Game Ova. You will love the th400 at the track. Launching becomes much easier and consistent and ET's drop like a rock! I had a different experience when I switched from the t56 to the th400. My car felt much slower but was .5 quicker at the track with no other changes.
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From: Washington
Just horror story's I've heard and recommendation from FTI for my Glide install
My pro ratchet has a reverse lockout, but any slight misadjustment in the linkage or something like a floor jack misplaced could open the reverse passages when up shifting from high gear
Doing any speed on the big end I'd like to know it's not going to hit reverse and end up on the roof. You never know when something might go wrong and you'll want to put it in neutral. I bought a brake like this just for the neutral capability
But if its a reverse pattern I guess it's no big deal, I prefer forward pattern
My pro ratchet has a reverse lockout, but any slight misadjustment in the linkage or something like a floor jack misplaced could open the reverse passages when up shifting from high gear
Doing any speed on the big end I'd like to know it's not going to hit reverse and end up on the roof. You never know when something might go wrong and you'll want to put it in neutral. I bought a brake like this just for the neutral capability
But if its a reverse pattern I guess it's no big deal, I prefer forward pattern
As Nathan said, if your shifter has a reverse light switch just wire it to the transbrake so when you put it in reverse it completes the circuit.
One more word of caution not so much about hitting reverse, but some transbrakes work ONLY in first and reverse but some will activate no matter what gear you are in. My friend hit his button by mistake going down the track with his TH400 and it locked the back tires up. He didn't wreck the car but it caused a whole bunch of havoc on the drivetrain.
One more word of caution not so much about hitting reverse, but some transbrakes work ONLY in first and reverse but some will activate no matter what gear you are in. My friend hit his button by mistake going down the track with his TH400 and it locked the back tires up. He didn't wreck the car but it caused a whole bunch of havoc on the drivetrain.
I used to throw the shifter into 2nd to get it to freewheel like it is in neutral on the big end. However, I have since changed my driving habits as this is a big no no and could cause the drum to explode and come through the case and floor board. The experts say you must leave it in 3rd gear and engine brake on the big end unless you have the special shift pattern vb/shifter. Also, the trans experts say to never downshift into first or second while the vehicle is moving as this is the equivalent to neutral dropping the trans.
I also learned the hard way not to just stab the throttle in a freewheel type TH400 coasting from 1st or 2nd gear roll. I sheared the lugs off the inside of the case twice before I found out why it was happening. Expensive lesson.
Thread Starter
TECH Junkie
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What shifter do you have? You can wire the trans brake into the reverse light switch and get reverse, but I would use a toggle or something to shut it off at the track so if you go into neutral on the big end you don't accidently get reverse
My vote is a 35 spline 9 inch!
My vote is a 35 spline 9 inch!
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Yea, you have to pull up on the shifter while In 1st In order to go to neutral reverse or park. And I'm running a full manual reverse. *edit* I take that back, you can go to neutral straight from 1st gear.
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What PTC unit is it? PN? What Ecu are you using? I limit my RPM to 3400-3600 or so on the brake. Once boost starts building it will fly past 5k as well without the 2-step active. I'm under 4% slip thru the traps at 6200rpm with the 9.5" PTC (14 stator). Trying to launch in 1st over 5k and 16ish lbs probably won't work well... may blow that rear end in a hurry too! Might try foot brake stuff till you can get a rearend under there. Also the taller you go on the gearing the weaker they get. A 2.7x is a pretty weak gear in general...even in a 9".
Good luck!
Good luck!
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Yea, I'm now beginning to wonder if my clutch was slipping when I still had the t56...car seems to pull MUCH harder now.
It's a PTC unit. I may have altered the stall speed (slightly) inadvertently, as I restricted the converter feed circuit to keep from killing my thrust bearings.
It's a PTC unit. I may have altered the stall speed (slightly) inadvertently, as I restricted the converter feed circuit to keep from killing my thrust bearings.
Any way to monitor cooler line pressure? I think it needs to be around 100psi ish.
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I used a 5/16 18 pitch set screw, tapped the converter feed hole....screwed it down in the hole and drilled it .110. I went that small because of the fixed/high line pressure. From what I've seen, if you're still running a low pressure pump spring you don't have to go that small.
I used a 5/16 18 pitch set screw, tapped the converter feed hole....screwed it down in the hole and drilled it .110. I went that small because of the fixed/high line pressure. From what I've seen, if you're still running a low pressure pump spring you don't have to go that small.
My th400 has the pump mod done to it (sorry I don't know the size of the hole) and it's roughly 65 psi at an idle. It'll knock your teeth out when it shifts second and third is nice and firm also. From what I understand, the converter turns into a pump once the RPMs increase which can put a strain on the thrust if the base pressure is too high.
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My th400 has the pump mod done to it (sorry I don't know the size of the hole) and it's roughly 65 psi at an idle. It'll knock your teeth out when it shifts second and third is nice and firm also. From what I understand, the converter turns into a pump once the RPMs increase which can put a strain on the thrust if the base pressure is too high.
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Funny you ask this, as I was driving to work last night (mainly freeway) I did think about the t56. With 273s and the 400 I felt like the car was buzzing pretty good, not sure how fast I was going but the motor was running 2500. Also had one of those "glad no one saw that" moments, I hopped in the car more than once reaching for the clutch to start the car. But overall I'm happy with the swap, I can already tell the car is much faster than it ever was with the6 speed. And shout out to PTC, this converter is straight business.....it's a bit mushy down low out of boost. But when you get into boost or flat out mat it, it tightens up nicely and it's hard to tell that it's not a lockup converter. Not sure what the car will run like at the track, but whatever it runs...I'm still not going to hack my car up putting a cage In it.
