mtpturbo
08-16-2007, 10:01 AM
Hutch,
I've got a toasted TH400 and am hoping you can offer me your thoughts. The trans is pretty basic, a th400 with 34 element sprag, TCI input shaft/drum and a JW transbrake. The trans has roughly 20 hard passes (some doing burnouts the "wrong way") and probably 300-400 miles of street driving (with a trans cooler ). I'm running a PTC convertor which flashes around 5500-6000 with my F-1R blower and just a touch lower with the current turbo setup. Anyway, I tore the trans down last night and found the following: Forward clutch pack looks like brand new, direct clutches showing some signs of slippage (a few "hot spots" on the steels), and the Intermediate clutch pack is gone, barely any facing left on the clutches. When I originally built it a few years ago I was advised to use the steel rings on the center support (now I see that is a bad thing..). The direct drum looks like it had rubbed the center support, the i.d. of the drum is slightly worn where it lines up over the center support. All of the thrust washers look good, but I would estimate there was 0.030" of endplay in the front half of the trans as built, would that have anything to do with anything, or are the steel rings the culprit?
I intend to get the endplay tighter when it all goes back together this time. I'm also going to add a steel clutch hub, a TH475 planet set, teflon rings, new seals/clutches and possibly an aluminum direct drum. I would like the trans to live at 1400hp, do you suggest any other mods?
Thanks,
Chris
I've got a toasted TH400 and am hoping you can offer me your thoughts. The trans is pretty basic, a th400 with 34 element sprag, TCI input shaft/drum and a JW transbrake. The trans has roughly 20 hard passes (some doing burnouts the "wrong way") and probably 300-400 miles of street driving (with a trans cooler ). I'm running a PTC convertor which flashes around 5500-6000 with my F-1R blower and just a touch lower with the current turbo setup. Anyway, I tore the trans down last night and found the following: Forward clutch pack looks like brand new, direct clutches showing some signs of slippage (a few "hot spots" on the steels), and the Intermediate clutch pack is gone, barely any facing left on the clutches. When I originally built it a few years ago I was advised to use the steel rings on the center support (now I see that is a bad thing..). The direct drum looks like it had rubbed the center support, the i.d. of the drum is slightly worn where it lines up over the center support. All of the thrust washers look good, but I would estimate there was 0.030" of endplay in the front half of the trans as built, would that have anything to do with anything, or are the steel rings the culprit?
I intend to get the endplay tighter when it all goes back together this time. I'm also going to add a steel clutch hub, a TH475 planet set, teflon rings, new seals/clutches and possibly an aluminum direct drum. I would like the trans to live at 1400hp, do you suggest any other mods?
Thanks,
Chris