question about shifting and nitrous

[silvergtjrad]

I tested out my nitrous kit for the first time last week and was having some issues with my transmission when was shifting gears. I can feel the car try to shift a couple of times before it actually gets in gear, this is while spraying. Im suspecting that spraying during the shifts is what is causing this but I have read through others' threads about spraying through shifts and nobody seemed to have this problem. Ive got a window switch so it can be shut off before the trans shifts, but id rather spray through them than cut the spray on and off all of the time. FYI Im driving an 02' grand am and its being sprayed with a 75 wet shot.

[sharkey]

the 4t45e isnt able to cope with the extra power during the shift, not with stock tuning. an option is to get hp tuners or another tuning program and up the epc pressure. this will firm up the shifts and will give you less slipping during the shifts. another option is to find a used autotrans interceptor or get a b&m shift improver. it plug inline with the tranny and ups the line pressure.

[silvergtjrad]

Ive got a powertuner, and the pressure is already raised some. I'll try increasing it some more again tomorrow. I did a couple of more test runs tonight, after programming the controller to cut the nitrous at 5500rpm (shifts at 5600) it still did the same thing. Thanks for the input though, never thought about that.

[Blackrider]

What are your shift times like?

[silvergtjrad]

1st to 2nd
,Seconds
Ft/LB Step 0,0.3
Ft/LB Step 2,0.3
Ft/LB Step 4,0.3
Ft/LB Step 6,0.3
Ft/LB Step 8,0.2875
Ft/LB Step 10,0.2875
Ft/LB Step 12,0.2875
Ft/LB Step 14,0.2875
Ft/LB Step 16,0.2875
Ft/LB Step 18,0.25
Ft/LB Step 20,0.25625
Ft/LB Step 22,0.2625
Ft/LB Step 24,0.2875
Ft/LB Step 26,0.3
Ft/LB Step 28,0.3
Ft/LB Step 30,0.2875
Ft/LB Step 32,0.2875

[JMo60]

my grand prix likes to tag the rev limiter between shifts (on the spray), then bang into gear chirping the tires... i do have a 4t60-e however, but it sounds as if it may be a somewhat similar problem...

by the way, what kind of system and shot are you using?

[silvergtjrad]

Its a dynotune 75 wet shot. Im not spraying it anymore for the time being. After having the trans problem I changed the jets to a 35 shot and it shifted fine but knocked like crazy. Ive got some valvetrain noise now and Im not going to risk blowing anything up.

[john_V63400]

oooh, I bet ur pistons shot

[silvergtjrad]

oooh, I bet ur pistons shot

I doubt that, Ive driven my car about 1000 miles since then and it runs fine other than hearing a little valvetrain noise.