650WHP turbo car, TH400 conversion - need input
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650WHP turbo car, TH400 conversion - need input I just got the car off the dyno and it put down 643/673 on pump gas, conservative timing and 13psi. I'm going to go to race gas, add timing, and start shooting for 18-20psi.
Needless to say, my stock T-56 is going to be hating life. So I've lined up a straight up swap to get a TH400 into the car.
I'm going to miss "driving/rowing" the car down the 1320, but I think the TH400 at this point is a necessary evil.
Question is, what gears should I drop into the rear if I'm just under stock weight and planning on trapping around 145?
Thanks for any pointers.
Needless to say, my stock T-56 is going to be hating life. So I've lined up a straight up swap to get a TH400 into the car.
I'm going to miss "driving/rowing" the car down the 1320, but I think the TH400 at this point is a necessary evil.
Question is, what gears should I drop into the rear if I'm just under stock weight and planning on trapping around 145?
Thanks for any pointers.
How tall are the tires and where are you shifting at are things to also think about.
http://www.wallaceracing.com/calcrgr.php
That should get you close
http://www.wallaceracing.com/calcrgr.php
That should get you close
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From: NW Burbs of Chicago
28" MT ET Drags @ the track, 275/40/17 (for now) on the street. power starts falling off around 6400RPM.
Which raises a good Q. How does one adjust the shift points on a TH400?
I'll check both links. Thanks guys.
Which raises a good Q. How does one adjust the shift points on a TH400?
I'll check both links. Thanks guys.
are you going with a manual valvebody or an automatic valvebody?
Hopefully its a manual valve body, in that case just move the shifter lol.
Reverse manual V/B is the only way to go.
EDIT:
Since its manual theres no adjusting anything, it only shifts when you make it.
Reverse manual V/B is the only way to go.
EDIT:
Since its manual theres no adjusting anything, it only shifts when you make it.
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Verdad Gallardo Same thing I have. I trap about 150 or so with my stock 3.73 gear ratio. But I have a 4l80e with manual shift, so I don't know if that makes a huge difference but I don't think it should.
No f-body came with stock 3.73 gears, what do you have, a monte carlo or something? They came with 3.73's I think, or atleast could.
4L80 will be different than his 400 b/c the gear ratios are different.
4L80 will be different than his 400 b/c the gear ratios are different.
I'm sorry I screwed up I typed in the wrong thing. Just too much stuff to remember. I had 3.23, but when the rear end was replaced and everything else along with the center section, the gears were change to 3.73.
There are some v6 TA's that did come with 3.73 gears in the rear.
There are some v6 TA's that did come with 3.73 gears in the rear.
I did the same thing a few years ago....best thing I ever did. You will miss rowing the gears in your t56 up until you take that first test drive with the th400. Driving it on the street is sooooo much more fun, point and shoot...alot faster stop light to stop light too.
I went MRVB with mine, had 3.73's (moser 12 bolt) then switched to 3.08's to help with the highway thing. You will need taller tires if you choose the same gear with that mph. Make sure you get a good converter...I bought a $280 cheapo and think it kept me out of the 9's.
I went MRVB with mine, had 3.73's (moser 12 bolt) then switched to 3.08's to help with the highway thing. You will need taller tires if you choose the same gear with that mph. Make sure you get a good converter...I bought a $280 cheapo and think it kept me out of the 9's.
Trust me, with a turbo car you won't miss the T56. Your car will be so much quicker and more controllable with a RMVB TH400 you won't even look back after your first drive. With a 28" tall tire, shifting around 6600 rpm, and estimated traps of 145 you won't want to go higher than a 3.55, probably around a 3.40 of sorts... but of course that depends on how much slip your converter has up top as well. A TH400 turbo converter will make or break the combo, spend money on a good converter.
My car put down around 566 rwhp and 540 lb ft with my T-56 in NC with perfect 50 degree weather. Now I just had tuned it for the first time with the TH-400 in Florida with temps at 99 degrees and high humidity and it put down 550 rwhp and 505 lb ft! I don't understand this because the tune was barely changed. All that happened was it was fattened up a bit up top and added a few degrees of timing and smoothed the idle out. I guess the difference is in the tuners because the weather was sure as hell not an advantage. With both tunes we were spraying a 50% meth/50% water mix.
The TH-400 will help you out a lot at the track. I dropped .4 tenths in the 1/4 mile with it running with my old six speed tune. I have yet to run it with my new tune but I will soon. The only problem is I have to deal with the Florida heat now and not the nice cool VA air.
The TH-400 will help you out a lot at the track. I dropped .4 tenths in the 1/4 mile with it running with my old six speed tune. I have yet to run it with my new tune but I will soon. The only problem is I have to deal with the Florida heat now and not the nice cool VA air.
Last edited by Packy; May 14, 2010 at 11:09 AM.
my car has a th400 3.73 gear and a 28" tire. ptc converter. with 3 or 4 lbs of boost im on the *** of a 06 cbr 600rr from a 20 to 140 is roll. i know its not that great but the car feels like a turd to me. the race shows differantly every one says the car feels slower with a th400 then an m6 but the th400 is faster, there right