Brought to you in part by:

.

Shop Eastwood for your Auto Restoration Needs!


  Mustangsandmore Forums
  Ford Racing
  Launching ABOVE stall rpm?

Post New Topic  Post A Reply
profile | register | preferences | faq | search

UBBFriend: Email This Page to Someone! next newest topic | next oldest topic
Author Topic:   Launching ABOVE stall rpm?
65_289
Gearhead

Posts: 761
From:
Registered: Jul 2001

posted 08-22-2002 01:08 PM     Click Here to See the Profile for 65_289   Click Here to Email 65_289     Edit/Delete Message   Reply w/Quote
Can you do it with a trans brake? I always thought that you couldn't launch above the stall rpm of the converter, but now I am being told that you can. These automatics are so confusing!

IP: Logged

steve'66
Gearhead

Posts: 6522
From: Sonoma,CA,USA
Registered: Mar 2000

posted 08-22-2002 01:27 PM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
NO,

The max engine speed on the t-brake is the stall rpm.

SteveW

IP: Logged

65_289
Gearhead

Posts: 761
From:
Registered: Jul 2001

posted 08-22-2002 01:39 PM     Click Here to See the Profile for 65_289   Click Here to Email 65_289     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by steve'66:
NO,

The max engine speed on the t-brake is the stall rpm.

SteveW


So if you had a 2500 stall, that would be the highest you could launch, right?

IP: Logged

steve'66
Gearhead

Posts: 6522
From: Sonoma,CA,USA
Registered: Mar 2000

posted 08-22-2002 01:58 PM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
You could set the two step higher, but then why bother using a two step. Your confusion may be because some car's foot brakes aren't good enough to hold the car back to the converter's real stall speed. Like a t-brake can.

SteveW

IP: Logged

65_289
Gearhead

Posts: 761
From:
Registered: Jul 2001

posted 08-22-2002 02:06 PM     Click Here to See the Profile for 65_289   Click Here to Email 65_289     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by steve'66:
You could set the two step higher, but then why bother using a two step. Your confusion may be because some car's foot brakes aren't good enough to hold the car back to the converter's real stall speed. Like a t-brake can.

SteveW


The reason I ask is because I have gotten a recommendation from 2 converter companies saying that a 2500 stall is what I would need. And since I am used to launching the 5 speed at 5500, 2500 seems like bog city to me.

IP: Logged

steve'66
Gearhead

Posts: 6522
From: Sonoma,CA,USA
Registered: Mar 2000

posted 08-22-2002 02:58 PM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
Yeah,

I think your car will be a pig with a 2500 stall converter.

SteveW

IP: Logged

kid vishus
Gearhead

Posts: 4538
From: middle of NC
Registered: Oct 2000

posted 08-22-2002 06:48 PM     Click Here to See the Profile for kid vishus   Click Here to Email kid vishus     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by steve'66:
Yeah,

I think your car will be a pig with a 2500 stall converter.

SteveW


I agree with Steve. that's way too tight of a convertor. I would have guessed more around 4000, unless it's street driven alot, then I ouwld still say at least 3000-3200. I would definatley call someone else and see what they say. Maybe the motor needs more cam and that is confusing the tech people.

IP: Logged

65_289
Gearhead

Posts: 761
From:
Registered: Jul 2001

posted 08-22-2002 06:49 PM     Click Here to See the Profile for 65_289   Click Here to Email 65_289     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by kid vishus:
I agree with Steve. that's way too tight of a convertor. I would have guessed more around 4000, unless it's street driven alot, then I ouwld still say at least 3000-3200. I would definatley call someone else and see what they say. Maybe the motor needs more cam and that is confusing the tech people.


It's driven to and from the track; that's all the street it sees.

IP: Logged

steve'66
Gearhead

Posts: 6522
From: Sonoma,CA,USA
Registered: Mar 2000

posted 08-22-2002 08:00 PM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
4,000 stall YES

Next time you call them don't mention the street and see what they say.

SteveW

IP: Logged

Rustang
Gearhead

Posts: 471
From: Clarion PA
Registered: Nov 2000

posted 08-22-2002 09:46 PM     Click Here to See the Profile for Rustang   Click Here to Email Rustang     Edit/Delete Message   Reply w/Quote
Some things to consider:
Don't forget that a torque converter can produce over 2 times engine torque at stall.
What stall speed you choose will really depend on what rpm maximum torque happens with your engine. You want stall to occur just slightly below or at max torque for best performance. If your motor makes max torque at 2700, then 2500 stall might be good. My guess is, however, like the other guys, that a hot street 289 will probably have max torque around 3500.
My experience is make sure the converter mfg. builds a converter tailored to your combo, and not simply pull their "standard" item off the shelf and sell it to you. Chances are you won't be happy.

------------------
'68 mustang 351 clevor- 10.92@124
'67 Stang, 351W -11.18@118
'69 351C Torino-14.90@100
'78 Pickup 351W-15.56@88
'79 Pickup 460 ET=??

IP: Logged

steve'66
Gearhead

Posts: 6522
From: Sonoma,CA,USA
Registered: Mar 2000

posted 08-22-2002 09:51 PM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
Russ,

His dyno sheet said max torque about 4200 if I remember an earlier post correctly. So you agree with us.

The wrong converter is what gives automatics a "bad rap".

SteveW

IP: Logged

65_289
Gearhead

Posts: 761
From:
Registered: Jul 2001

posted 08-22-2002 10:00 PM     Click Here to See the Profile for 65_289   Click Here to Email 65_289     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by steve'66:
Russ,

His dyno sheet said max torque about 4200 if I remember an earlier post correctly. So you agree with us.

The wrong converter is what gives automatics a "bad rap".

SteveW


You're very close; it was 4100. But the weird thing was the horsepwoer really struggled from 5200-6200; only gaining like 12 hp in that band. I don't know if it's the 1 1/2 primaries on teh tri-y's, or the Pertronix, or what, but that ain't right, either!

IP: Logged

steve'66
Gearhead

Posts: 6522
From: Sonoma,CA,USA
Registered: Mar 2000

posted 08-22-2002 10:08 PM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
You've GOT to get rid of those why-try headers! A cheap set of Headmans ($100) will let it breath up top!

SteveW

IP: Logged

65_289
Gearhead

Posts: 761
From:
Registered: Jul 2001

posted 08-22-2002 10:36 PM     Click Here to See the Profile for 65_289   Click Here to Email 65_289     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by steve'66:
You've GOT to get rid of those why-try headers! A cheap set of Headmans ($100) will let it breath up top!

SteveW


I was thinking of Super Comps for my birthday in October........

IP: Logged

steve'66
Gearhead

Posts: 6522
From: Sonoma,CA,USA
Registered: Mar 2000

posted 08-22-2002 11:45 PM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
SuperComps are even better.

SteveW

IP: Logged

All times are ET (US)

next newest topic | next oldest topic

Administrative Options: Close Topic | Archive/Move | Delete Topic
Post New Topic  Post A Reply
Hop to:

Contact Us | Mustangsandmore Front Page

Copyright 2003, Steve LaRiviere. All Rights Reserved.


Ultimate Bulletin Board 5.47d

Amazon Honor System Click Here to Pay Learn More

[Acronyms][Calendar][Chat][Classifieds] [Members' Pics]

[ Mustangsandmore.com Bookstore] [Mustangsandmore.com T-Shirts][Tech Articles]