superpilun

I've got a weird problem...my auto tranny doesn't seem to want to shift. It just hangs in high rpm for a few seconds until shifting, or I have to let off the gas momentarily to shift.

Also, is the TD04HL a good sized turbo for my 1.8L engine? My high rpm seems to be suffering. Lots of torque though. It could be my pre-intercooler pipes, which are 1.75" OD (I just tried to match the compressor outlet hole).

Any thoughts?

Boosted '99 Corolla

superpilun

anyone?

texlurch

My auto shifts fine.. but it is a manual valve body.

I am not familiar with the 4-bangers, but if you have a vacuum line that is going to the tranny, that may be your problem. It is waiting for a vacuum signal that never comes when you are under boost. Does it shift ok at part throttle?

superpilun

wow a vacuum line that goes to the tranny? i should look for that.

thanks. but it also does shift fine at partial throttle.

superpilun

my filter was too restrictive, i fixed that and the upper revs are much better now.

ZexRex

boost shouldnt mess up how your tranny shifts, it just gets you to redline faster. it prob did the same thing before turbo

Kevin325isBMW

I believe the increased torque of a turbocharged engine can disrupt proper automatic transmission shifting. I read about in in "Turbochargers" by Hugh MacInnes.

Kevin

bikerchris13

i've always heard it will help the tranny shift if you let off at or near redline to take the stress off it and then get back in it... just an off-on deal quickly

superpilun

yes that's pretty much what i have to do, otherwise it just lingers around near redline. strange.

89dxhunchback

clutchs slipping... 100hp car, then 200hp car... you don't thing the is going to slip a little ?

Auto = good !! Launch with boost !!!