How does one properly launch an auto by utilizing the torque converter?

InlineFive

Diamond Member
Sep 20, 2003
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How is this done properly? I have a '95 850 Turbo with an automatic transmission.

And yes, I did check with Google first.
 

EatSpam

Diamond Member
May 1, 2005
6,423
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When I launch an auto, I just press the accelerator. Its an automatic ...
 

spidey07

No Lifer
Aug 4, 2000
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give enough gas to not break the tires then mash on it.

On the 850 turbo I had way back it was about 3/4 throttle then all the way.
 

AgaBoogaBoo

Lifer
Feb 16, 2003
26,108
5
81
Yeah, should be around 3/4 throttle to launch and then just floor it of course

I'd get an 850 Turbo if they made more manuals... it's too bad they don't...
 

spidey07

No Lifer
Aug 4, 2000
65,469
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Oh.

Don't be stupid and try to hold the brake while you press the gas.

You'll be limping along sans turbo.
 

InlineFive

Diamond Member
Sep 20, 2003
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Thanks for the fast responses!

One more question, I read that the stall RPM for these cars is at about 2900RPM. Is that the optimal time to release the brake or is it irrelevant?
 

InlineFive

Diamond Member
Sep 20, 2003
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Originally posted by: spidey07
Oh.

Don't be stupid and try to hold the brake while you press the gas.

You'll be limping along sans turbo.

Do you mean hold the emergency brake?

Basically what I gather is this:

1. Hold down brake pedal.
2. Press gas to build up torque.
3. Release brake and mash gas.
 

SuperSix

Elite Member
Oct 9, 1999
9,872
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Originally posted by: spidey07
Oh.

Don't be stupid and try to hold the brake while you press the gas.

You'll be limping along sans turbo.

It's a shame you have no idea what you're talking about.

You should powerbrake it somewhat to spool the turbo, basically, press the brake hard, and press the gas SLOWLY until you the car starts overpowering the brakes. When the lighyt goes green, floor it, and release the brake pedal.

<-- Has owned and raced Turbo Buicks (ie Grand National) for over 7 years.

Although this is written for Turbo Buicks - much of it may help you..

http://gnttype.org/techarea/sunday.html
 

InlineFive

Diamond Member
Sep 20, 2003
9,599
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Originally posted by: SuperSix
Originally posted by: spidey07
Oh.

Don't be stupid and try to hold the brake while you press the gas.

You'll be limping along sans turbo.

It's a shame you have no idea what you're talking about.

You should powerbrake it somewhat to spool the turbo, basically, press the brake hard, and press the gas SLOWLY until you the car starts overpowering the brakes. When the lighyt goes green, floor it, and release the brake pedal.

<-- Has owned and raced Turbo Buicks (ie Grand National) for over 7 years.

Although this is written for Turbo Buicks - much of it may help you..

http://gnttype.org/techarea/sunday.html

Thanks for the clear cut reply. Appreciate it. :)
 

spidey07

No Lifer
Aug 4, 2000
65,469
5
76
Originally posted by: SuperSix
Originally posted by: spidey07
Oh.

Don't be stupid and try to hold the brake while you press the gas.

You'll be limping along sans turbo.

It's a shame you have no idea what you're talking about.

You should powerbrake it somewhat to spool the turbo, basically, press the brake hard, and press the gas SLOWLY until you the car starts overpowering the brakes. When the lighyt goes green, floor it, and release the brake pedal.

<-- Has owned and raced Turbo Buicks (ie Grand National) for over 7 years.

Although this is written for Turbo Buicks - much of it may help you..

http://gnttype.org/techarea/sunday.html

Its a shame that I owned that car (850 turbo) and speak from experience and not what you read on the web.

dumbass.

I swear this board is severely flooded with talking out of their ass and what they read on the intarweb.

-edit- sorry. I was a little harsh. We all know that the turbo in the grand national is much, much, much better than what the 850 has.
 

Goosemaster

Lifer
Apr 10, 2001
48,775
3
81
Originally posted by: spidey07
Originally posted by: SuperSix
Originally posted by: spidey07
Oh.

Don't be stupid and try to hold the brake while you press the gas.

You'll be limping along sans turbo.

It's a shame you have no idea what you're talking about.

You should powerbrake it somewhat to spool the turbo, basically, press the brake hard, and press the gas SLOWLY until you the car starts overpowering the brakes. When the lighyt goes green, floor it, and release the brake pedal.

<-- Has owned and raced Turbo Buicks (ie Grand National) for over 7 years.

Although this is written for Turbo Buicks - much of it may help you..

http://gnttype.org/techarea/sunday.html

Its a shame that I owned that car (850 turbo) and speak from experience and not what you read on the web.

dumbass.

spidey...you kill..me...:laugh:
 

InlineFive

Diamond Member
Sep 20, 2003
9,599
2
0
Originally posted by: spidey07
Originally posted by: SuperSix
Originally posted by: spidey07
Oh.

Don't be stupid and try to hold the brake while you press the gas.

You'll be limping along sans turbo.

It's a shame you have no idea what you're talking about.

You should powerbrake it somewhat to spool the turbo, basically, press the brake hard, and press the gas SLOWLY until you the car starts overpowering the brakes. When the lighyt goes green, floor it, and release the brake pedal.

<-- Has owned and raced Turbo Buicks (ie Grand National) for over 7 years.

Although this is written for Turbo Buicks - much of it may help you..

http://gnttype.org/techarea/sunday.html

Its a shame that I owned that car (850 turbo) and speak from experience and not what you read on the web.

dumbass.

I swear this board is severely flooded with talking out of their ass and what they read on the intarweb.

It's a shame that both of you jumped to each other's throats so quickly.

Otherwise, I am a little confused by your response about not holding the brake. It seems to me that pressing the brake pedal is essential whilst gently accelerating the engine. Otherwise it seems like a moot point.
 

spidey07

No Lifer
Aug 4, 2000
65,469
5
76
Go ahead and try it.

Post back with the results.

Make sure you have a cell phone handy.
 

tfinch2

Lifer
Feb 3, 2004
22,114
1
0
Put the car in neutral, rev the engine all the way to the limiter, and slam it in drive. :)
 

spidey07

No Lifer
Aug 4, 2000
65,469
5
76
Originally posted by: PorBleemo
Originally posted by: spidey07
Go ahead and try it.

Post back with the results.

Make sure you have a cell phone handy.

Now I'm really curious, why? :)

Give it a shot, post back....let us know what happens.
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
44
91
You won't hurt the turbo at all by holding the brake.

What you _will_ do is generate a _LOT_ of heat in the torque converter (it's not a 2900 RPM stall converter, a 2900 RPM stall converter won't begin pushing the car until 2900 RPM, meaning there would be no creep at idle) and potentially blow out some seals in the transmission. Unless you have messed with the transmission for racing, you should not "power brake" past maybe 1,500 RPM, and even then you should not do it regularly.

ZV

EDIT: The above answer assumes that you want your transmission to last 100,000 miles or more. If you don't mind a 10,000 mile (or less) transmission life, by all means hold the brake on for as long as you like.
 

spidey07

No Lifer
Aug 4, 2000
65,469
5
76
Originally posted by: PorBleemo
Originally posted by: spidey07
Originally posted by: SuperSix
Originally posted by: spidey07
Oh.

Don't be stupid and try to hold the brake while you press the gas.

You'll be limping along sans turbo.

It's a shame you have no idea what you're talking about.

You should powerbrake it somewhat to spool the turbo, basically, press the brake hard, and press the gas SLOWLY until you the car starts overpowering the brakes. When the lighyt goes green, floor it, and release the brake pedal.

<-- Has owned and raced Turbo Buicks (ie Grand National) for over 7 years.

Although this is written for Turbo Buicks - much of it may help you..

http://gnttype.org/techarea/sunday.html

Its a shame that I owned that car (850 turbo) and speak from experience and not what you read on the web.

dumbass.

I swear this board is severely flooded with talking out of their ass and what they read on the intarweb.

It's a shame that both of you jumped to each other's throats so quickly.

Otherwise, I am a little confused by your response about not holding the brake. It seems to me that pressing the brake pedal is essential whilst gently accelerating the engine. Otherwise it seems like a moot point.

SuperSix is indeed correct on how to launch on his very nice car that I'm sure he is very familiar with, with a motor/turbo built to run. I love the grand nationals.

The 850 is not such a car.

Try it with your 850. Just make sure you have a cell phone handy when you pop a hose. They are not the same animal. Too much gas on the 850 and POP! No more turbo. At least on mine way back when it was a new car.

You're not really hurting anything, just too much pressure.
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
44
91
Originally posted by: spidey07
SuperSix is indeed correct on how to launch on his very nice car that I'm sure he is very familiar with, with a motor/turbo built to run. I love the grand nationals.

The 850 is not such a car.

Try it with your 850. Just make sure you have a cell phone handy when you pop a hose. They are not the same animal. Too much gas on the 850 and POP! No more turbo. At least on mine way back when it was a new car.

You're not really hurting anything, just too much pressure.
Spidey, unless the boost controller is malfunctioning, the wastegate will open well before boost becomes sufficient to damage the engine. The boost control doesn't care (or know) that the engine is revving against the torque converter, it will still bleed boost once design boost is exceeded. The real danger is overheating the transmission.

ZV
 

DaTT

Garage Moderator
Moderator
Feb 13, 2003
13,295
122
106
Originally posted by: PorBleemo
Thanks for the fast responses!

One more question, I read that the stall RPM for these cars is at about 2900RPM. Is that the optimal time to release the brake or is it irrelevant?

Yes...but get a higher stall convertor
 

spidey07

No Lifer
Aug 4, 2000
65,469
5
76
Originally posted by: Zenmervolt
Originally posted by: spidey07
SuperSix is indeed correct on how to launch on his very nice car that I'm sure he is very familiar with, with a motor/turbo built to run. I love the grand nationals.

The 850 is not such a car.

Try it with your 850. Just make sure you have a cell phone handy when you pop a hose. They are not the same animal. Too much gas on the 850 and POP! No more turbo. At least on mine way back when it was a new car.

You're not really hurting anything, just too much pressure.
Spidey, unless the boost controller is malfunctioning, the wastegate will open well before boost becomes sufficient to damage the engine. The boost control doesn't care (or know) that the engine is revving against the torque converter, it will still bleed boost once design boost is exceeded. The real danger is overheating the transmission.

ZV

I understand. But i popped many a hose with my 850 turbo when I tried.

Like I said, its first hand experience and maybe something was wrong. From what I 'heard' (meaning heard from the turbo/motor), it didn't waste or bleed. There were many complaints on the 850 from what I remember but I still loved that car.

There was no damage to the motor/turbo. Just blown hoses.
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
44
91
Originally posted by: spidey07
I understand. But i popped many a hose with my 850 turbo when I tried.

Like I said, its first hand experience and maybe something was wrong. From what I 'heard' (meaning heard from the turbo/motor), it didn't waste or bleed. There were many complaints on the 850 from what I remember but I still loved that car.

There was no damage to the motor/turbo. Just blown hoses.
Either overboosting or loose hoses then. I've done the same with the 951. Blew the intake boot off the AFM at 15PSI above atmospheric. I use a bigger clamp now. :p

ZV
 

thedarkwolf

Diamond Member
Oct 13, 1999
9,037
132
106
boost is boost. It doesn't care if the car is moving or not. The only difference is there won't be air moving across the intercooler so it will heatsoak fairly quick. If you plan to take it to the strip often I would upgrade the tranny cooler.