Please tell me... how do you dyno a TR?

[BlackBeauty]

Hey folks, I know plenty of people have done this already, but how do you dyno in D with an automatic tranny? Sounds complicated. I've asked this before, but never get an answer. And tomorrow there is a local 'dyno-day' going on.
If you drive normal until the car shifts into OD, then floor it, it will downshift to D but the RPMs will be too high, and I would only get half of the dyno results (from 4k rpm's and up, for instance). Or if I drive normal into D, then floor it, it will just downshift into 2, right?
It has to be easier than I think, because hundreds and hundreds of people have dyno'd their autos. Thanks.

 

[turbo buicks]

i would ASSUME you just punch it in 1st till it shifts. would this work?

 

[victa1]

Leave the tranny in "D", slowly take it up to 70 or so it won't downshift into second, then nail it in third up to about 105.
You will then get the full throttle third gear RWHP numbers.
When basically stock, my 87 T did about 240 at the wheels.

 

[Irid]

Is there anyway to fake out the tranny so it doesn't kickdown? In know with the automatics on the 928's there is a solenoid that you pull and life is good. Looking through the tranny manuals I have for my tta, I don't see something that easy ;-(

If you lock the TC in third (with a switch) will that override the kickdown?

My tta is the first car with an auto I've owned...

 

[BlackBeauty]

Originally posted by victa1
Leave the tranny in "D", slowly take it up to 70 or so it won't downshift into second, then nail it in third up to about 105.
You will then get the full throttle third gear RWHP numbers.
When basically stock, my 87 T did about 240 at the wheels.

But being in D at 70mph is about 3500rpms or so. So I wouldn't get a full reading, that's the problem I'm trying to figure out. The peak torque on these cars is in the low 2000 rpms.

If there was a way to keep the car from down-shifting while getting a full 3rd gear run, that would be great.

 

[Brooks]

My tranny kept downshifting. we ended up doing the runs in 2nd gear. They came out fine.

Talk to your shop about it. They should be able to compensate for it just fine since they have both the engine RPM and dyno RPM.

Charles Brooks

 

[Snappy6]

I have a friend in Edwardsville IL. his shop is called Turbo Connections Racing and he has a chassis dyno. I've seen him put all kinds of cars on it. What he does is eases into the throttle through first then nails it with it in drive . Works every time .

 

[TurboDave]

Might want to try this. Start your run slowly building up steam in 2nd gear. When you are ready to floor it (in second gear) then upshift one gear to 3rd, don't shift up to OD.

 

[TurboJim]

Yea, but if you do it in 2nd, it'll take one of you smart guys to correct the readings as 2nd gear is like 1.8x:1. 3rd is 1:1 so readings will be true

I thought I read taking off the TV cable caused trans pressure to default high and the car wouldnt downshift.

Dont take that as gold, I may have not understood it right

 

[REDS HOT AIR]

someone needs to send this thread to tranny section