Granatelli Trans Tuner for GM

[JMo60]

I just found this in my newest summit update catalog. says it works with 4t60-e. Has anyone seen these or used them? claims to work like a shift kit. plugs into the wiring harness and increases line pressure and some other tricky stuff..

[JMo60]

no one has used these or knows anything about them.. i think its a new product

[torq455]

oh? my 4T60E is a 97 and i spent $13 on an adjustable modulator that will firm up the shifts. do the newer ones not have a vacuume modulator?

[sharkey]

hmmm, im not sure on how that works, as the 4t60e line pressure is controlled by the modulator, not electronicly.

ya sure it isnt for a 4t65e??? or a 4t40/45e???

[blackbombshell95]

B&M makes a vacuum shift improver

http://www.truckperformance.com/products/searchtype_56d/sortorder_ADAAA/productcategory_Shift+Improvement+Kits/category_Clutch+~~+Transmission/sf1_PONTIAC/sf2_1995/sf3_Grand+Prix/sf4_Vehicle+Specific+Kits/

[sharkey]

basicly, an adjustable modulator will do the same thing as the b&m one. im still researching the firth one thouigh.

[JMo60]

i have the B&M thing, and all i can say is that its worthless. its a vaccum line with a valve that costs $50.. part throttle shifts are improved, but WOT (where it counts) is the same. Im lookin for something to shift hard with power behind it.. plus the vaccum modulator wont make a difference at WOT because it is vaccum sensitive, and vaccum falls to almost 0 at WOT

[torq455]

right! and thus, more line psi. vac works a lever of sorts to lessen line psi at high vac. IF you unplug you vac line to the modulator, you will max out the pump and have hard shifts--though it will ruin the pump. get an adjustable modulator and dont' get greedy with the firmness.

[JMo60]

when you are pushing the type of power i am, you need a tranny to shift hard and fast. right now, the revs are climbing so fast that the transmission cant shift soon eneough, the revs keep climbing through my shifts untill the rev-limiter hits.. always in the 1-2 shift the car tags the rev limiter in the middle of the shift...

[torq455]

then you need to program you computer to shift sooner. or are you saying it's slipping to much to catch the engine when it should.

[3400-95-Modified]

you have a 75 shot, I have a 100, I'm not having this problem.. you have issues somewhere else...

[JMo60]

The Trans thats in the car is ready for retirement. im sure with a fresh tranny it would probably shift a little nicer, but im sure a more positive shift would pry still help a bit...
I have OBD 1.5, so i cant really tune it to do anything, thats why i thought this trans tuner would be nice.

BTW 3400-95-Modified I love your car

[3400-95-Modified]

Thanx, but yeah I'm in the same boat as you, OBD1.5 no programming capabilities... it sucks.

But this is why I'm changing my trans to 3.33 and putting in a LSD when i rebuild it next week... It only has 60k on it and the valve body is shitting the bed... so i got a new one and replaced all the valves with sonnax ones, that fix alot of shift issues, higher pressure valves and stuff, and yeah all the sonnax valve body fixes basically... plus a 2300 stall converter, and all of this hopefully will drop my et in to the mid 13's... rather than high 13's

I wanted to do this tuner but its a little expensive to "test" unfortuntely someone will have to invest the cash before anyone knows if it works. That just wont be me since I already spent so much on my trans.