Th400
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Joined: Jun 2007
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Th400 Ok, so im running an automatic turbo 400 tranny at the moment, taking my car to a tranny place in about a week. 3 gears, if im not floored, it shifts at like 5mph to 2nd at like 1250 rpms, and into 3rd at 25 at 1250. If im on the gas, it still shifts really early to 2nd unless im completely smoking the tires. Also, Going around 25ish, shouldnt it kick down to 1st not 2nd if i floor it? lastly, i took off the cover on my console to see how good/bad my shifter was, really sloppy so im pry throwing in a hurst racing shifter.. any comments on all this would be awesome, just looking for a little insight.. i want to get this straightened out and put in a shift kit. I wanna be able to lay rubber a few feet when i hit 2nd.
FormerVendor
Joined: Oct 2006
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From: D-F/W
Is this a transplanted 400 or factory ? If it's a transplant , do you have the detent solenoid hooked up and working properly ? If not that can cause the issues you describe because it plays a major part ithe the control of upshifts and downshifts! As far as " laying rubber " on upshifts the Testicular Fortitude of your engine has more to do with that than your transmission !!
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Joined: Jun 2007
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thanks a lot for the tips guys, Testicular Fortitude = Plenty =] Taking it in to a guy who specializes in transmissions to see what the deal is, also my linkage is a little loose and the stock shifter is really sloppy so im throwing in a hurst ratchet shifter and possibly a shift kit.
The detent solenoid as stated does have and affect on both kickdown and how long the trans holds gears at WOT only. And should be hooked up or you will quick shift at WOT. Some modulators have the ability to be ajusted by a small amount using a set screw located inside where the vaccum line conects to it which case raise the shift points but average 4-6 MPH. I these things dont give you what you want to will need to order a govenor weight and spring kit as mentioned and recalibrate the GOV. You dont mention what stall you have in it but this is a comon issue with TH350 and H400 Transmissions after installing a very high stall converter due to the vaccume created by the higher RPM verse the slow actual speed causing the govenor presure to be very low. Hope this helps a little .
Frank
Frank
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You need to check the vacuum at the modulator itself, it should change the characteristics of the idle when disconnected. Make sure that it is at a "true" vacuum source on the intake manifold, and not at the timed port passage, as this will cause the low speed early upshifts.
