BuickRacer

Yesterday I installed a D-I-Y shift kit and I wanted to post my observations.

I used 1" and 3/4" shims from the hardware store and replaced the stock 1-2 accumulator spring with a 2-3 spring (P/N 23203977) which is a much thicker coil. The car will now lightly bark the tires on the 1-2 at WOT and the 2-3 is mmm-okay; however, if & when I take the pan down again I will shim up the 2-3 accumulator spring 1/4" to see if I can get a little more pop on the 2-3. At light throttle the 1-2 is enough to let you know "hey, I'm happening now" but not outrageous.

Frankly, I think anyone looking to go the shift kit route will find the 1" & 3/4" shims to be just fine. Anyway, I hope this helps someone!

Sittingmongoose

iTrader: (1)

it acually chirps when it shifts? wow i cant even come close to getting mine to do that and i make a lot more power.

BuickRacer

Yes, at WOT. I have the line pressure upped a bit in the tune as well. My fear was that I would get a "dashboard in my lap" slam on the 1-2 but it has worked out okay.

94ss06gxp

iTrader: (5)

thanks for the info

blakss

iTrader: (4)

waiting to install the same shift kit just been way to cold out here but good to hear u like it

Compg

I had the same thing done on my GTP Comp G when I had it. DIY shift kit and line pressure increased. Loved it, until on the 1-2 shift I snapped the input shaft that grenaded my TC which in turn sent pieces into the rest of the tranny. $3200 later I had a race built tranny and was good to go.
Moral of the story is I wouldn't recommend both shims/spring DIY kit "and" increased line pressure to long on the 4t65e-HD, because we all know it's not HD.
Tate

nmp0098

HD only refers to the differential, everything else is the same mechanically. Otherwise, it's the TCM that keeps the trans alive (stock engine) with aggressive torque management.