Anyone with boosted automatics?
 

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

Re:Anyone with boosted automatics?
 

anyone?

Re:Anyone with boosted automatics?
 

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?

Re:Anyone with boosted automatics?
 

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

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

Re:Anyone with boosted automatics?
 

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

Re:Anyone with boosted automatics?
 

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

Re:Anyone with boosted automatics?
 

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

Re:Anyone with boosted automatics?
 

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

Re:Anyone with boosted automatics?
 

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

Re:Anyone with boosted automatics?
 

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

Auto = good !! Launch with boost !!!

Re:Anyone with boosted automatics?
 

I have an auto 1.6 sohc boosted. No problem with tranny so far (thank god). How Do you launch with boost? I've heard there should be less turbo lag with auto's? whats up with that?

Would love to talk to more people with turbo automatics.
any info would help.

thanks
civicgs400@aol.com

Re:Anyone with boosted automatics?
 

Yeah, my car seems to be fine now. I guess the restrictive filter I had before was causing it to freak out. I don't really launch per se I just step on the gas. Too much torque braking can accelerate wear to your torque converter. There is less lag with autos because if you watch your boost gauge as your tranny shifts, it doesn't go to zero (which is what happens in manual cars as you let off the throttle). Mine actually jumps about one psi as it shifts.

Re:Anyone with boosted automatics?
 

Holding the brake for a extended amount of time on an auto, can make the tranny temps get extremly hot, extremly fast.

My friend with a GN has a tranny temp guage, and he said he can watch the temp go from low-normal to TOO DAMN HOT, in a very short time.

Re:Anyone with boosted automatics?
 

Cool. Autos sound like a headache - one that myself has to put up with. sux. whatever. maybe I'll convert one of these days.

What about torque converters, ive heard something about that before. not to sure what its all about? ???

Re:Anyone with boosted automatics?
 

the torque converter is basically the clutch for autos. instead of friction plates, it uses a housing with vains and the thick gooey viscous fluid acts as the material that forces two things to spin together. if you torque brake you are forcing the two things to spin at separate velocities which rapidly heats up the viscous fluid.

upgraded torque converters allow you to have a higher stall rate, basically as you torque brake, the max rpm you can acheive during torque braking will be high allowing you to launch at a better power band. that's pretty much all it does.