car shifting at 4000

[buickstv87]

hi im new to this so please bear with me my car shifts at 4000 rpm fine if i move the detent cable to where turn more rpms it will act like the valve springs are bad i can let up on the throttle and it will shift & pull good it does this on the 1-2 shift could it be something in the trans checked valve springs by holding car in 1st & running it up to 5000 trans has been rebuilt with the good stuff car runs 7.80 1/8 5 psi launch stockturbo intercooler/exhaust/blue top inj/good heads 1.77 valves im sure it would run alot better with a 1000 more rpms any help would be greatly appriciated thanks steve

 

[streetknight]

I have no clue, but welcome to the board. Maybe some guru's will answer.

 

[Turbo Brian]

When you modify the engine to produce more torque, at some point, the calibration on the transmission governor will be wrong for the increased torque.

The governor is a centrifugal device so, as its rpm increases, the governor weights sling outward. The heavy weight will move out first at low road speeds sealing its check ball against the governor shaft. The light weight and spring control shift points at higher road speeds. To move the WOT shift points down, you will need to either find a stiffer spring or add weight to the light weight. To move the WOT shift points up, you need a combination of lighter springs and or weights.

Some Buick vendors have calibrated governors for sale to solve this problem. It is not much more difficult than a transmission filter change to change out the governor.

This link might help:

http://www.2004rperformancecenter.com/mcartfree/product.asp?intProdID=91

 

[turbo2nr]

Do not looosen cable. Press button, pull back, floor car and let it self-adjust.
Iamtehhrdtimereadingyoutypeded.

 

[bison]

The governor isnt effected by torque. Its effected by rpm (centifugal), springs or lack of, and oil pressure. Is the governor right for you 200? There are a ton of variations and they must be used with the correct valve body. The 1-2 will always occur a little higher than the 2-3 if you keep the shifter in drive. Thats just the way the governor circuit is on these transmissions. You could have at least an 1/8 inch difference on the tv cable length and the thing will still hit max tv. The only thing effected would be part throttle. Get the cable as tight as possible without limiting the throttle opening. Post pics of your governor and the letters and numbers on the valvebody. They should be BR3

 

[wiked87gn]

pull back your floor pad or take it out and cut a grove right behind the gas pedal on the carpet and go for a blast, hopefully that helps..

 

[streetknight]

If the car is not getting to the 5000 RPM range at WOT then the pressure will not be right for the TV correct? Wouldn't this be why it won't shift unless you back off the throttle.

If the engine can't get the RPM's in the range the governor is set up for and the drive shaft RPM's aren't high enough the pressure won't be right for it to shift.

I'm thinking Ignition problem of some kind.