T.V. modulator downshift valve

[TiBeu]

Hi guy's, I've installed a SUPERIOR K 200-4R V, .471 boost valve, .283 rev. boost valve and a G.N. intermidiate servo in a my tranny (HC) that comes from a Canadian 86 Cutlass, loockup in third and O.D.
Normal driving and 50% throttle 1-2, 2-3 and O.D. shifting is good and solid but at full throttle, 1-2 not solid, I'd say slip a little, what would be the problem. Thanks. Jean-Guy.

 

[77 cruiser]

How much power? Should have a .500 boost valve? May want to check the press.

 

[88S10Durango]

Hi I`m no Tech but mine was doing that from 1-2 & my 1-2 accumulator spring was broken ,???

 

[bison]

With those boost valves you have around 180 psi line. You should go to the larger .500 and .296 valves and put a gauge on there to verify pressures. Check pin to drum clearance and set up for around .060in. Sounds like the drum is glazed though since its ok at part throttle and you didnt mention anything wrong with the fluid. You should also install a CK shift recalibration kit. It includes a new set of accumulator springs and the accum valve spring in the vb. These parts make a big difference on a trans like yours and the boost valves and pressure reg spring are included in the kit.

 

[TiBeu]

Thank Bison. First I'd like to clarify the position of the downshift modulator valve in the valve body, in my ATSG (2003) revised edition book and the instruction sheet of my correction kit, the downshift and the upshift t.v. modulator valves are in the 3 and 4 position from the throttle valve side of the vb and in the opposite position in the diagnostic chart, I think you can clarify that.
The SUPERIOR 200-4R V kit consist of 8 springs and the .471 boost valve, Like I said, I've also installed a .283 reverse boost valve + G.N. servo.
Checking the pressures and positionning the throttle valve where it raise the pressure as soon as the throttle start mooving is the next thing I should do and also checking the clearance of the band pin.
The kit include:
A) adding a small spring inside the existing line bias valve spring.
B) replace T.V. modulator DNshift spring
C) replace T.V. and boost v. spring
D) replace 1-2 accumulator spring
E) replace servo cushion spring
F) replace press. reg. spring
G) added a spring inside the existing spring of the front pump slide.
No problem downshiftting from O.D. to 3rd on medium acceleration but at full acc from O.D. it'll go to 3 take a little while and go to 2nd.
I have that 2004R behind a rebuilt 1985, 4.3 chevy I was told cyclone turbo cam 3.23 locker in a 1976 Cossworth Vega 15,000 miles.
Thanks. Jean-Guy.