Automatic Crank HP-RWHP conversion and max HP limit - Mustang Evolution

Go Back   Mustang Evolution > 1979-2015 Mustang GT || Tech and Talk > 1996-2004 Mustang GT



Reply
 
Thread Tools Search this Thread
Please support our sponsors and let them know you heard about them here!
Old 04-23-2016, 03:39 PM   #1
Registered Member
Regular
 
Join Date: Oct 2014
Location: B.C
Region: Canada
Posts: 21
Automatic Crank HP-RWHP conversion and max HP limit

Hi Everyone. Thought I would want to get more educated on information about the stock Automatic of my 04. From what I read, the conversion of Crank HP to RWHP would be a loss of 15% on a manual. What would be the % loss of an Automatic?
Furthermore, what would be the MAX RWHP that a stock Automatic can take on the New Edge?
Thanks
__________________
2006 MUSTANG GT
KNIGHT4000 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 04-23-2016, 03:53 PM   #2
Junior Member
 
Join Date: Apr 2016
Location: Cape Coral
Region: Florida
Posts: 22
Quote:
Originally Posted by KNIGHT4000 View Post
Hi Everyone. Thought I would want to get more educated on information about the stock Automatic of my 04. From what I read, the conversion of Crank HP to RWHP would be a loss of 15% on a manual. What would be the % loss of an Automatic?

Furthermore, what would be the MAX RWHP that a stock Automatic can take on the New Edge?

Thanks


I'm not sure about the % loss but from what I heard it could handle 400 horsepower but it's really not horsepower you should look out for its more torque that destroys everything (this is all from just reading forums)
Fitzy_2v is offline   Reply With Quote
Old 04-24-2016, 12:39 AM   #3
Registered Member
Regular
 
Steve96's Avatar
 
Join Date: Jul 2013
Location: Waterford
Region: Michigan
Posts: 2,386
Quote:
Originally Posted by Fitzy_2v View Post
I'm not sure about the % loss but from what I heard it could handle 400 horsepower but it's really not horsepower you should look out for its more torque that destroys everything (this is all from just reading forums)
The trans in an 04 is one of the better automatic transmissions to have in a 99-04 Mustang. Its actually "beefed" up from the factory. They can handle a little more HP. I cant remember exactly what was upgraded on them, but Im sure someone will chime in. I want to say IIRC that the trans can hold more like 550-600 hp if in good condition. The 2v engine on the other hand is a time bomb over 450 whp and needs a forged roatating assembly.

Sent from my SM-G920P using Mustang Evolution mobile app
__________________
1996 GT
2003 GT
Follow on Instagram @manicmustangs
Follow on Instagram @steviesstangs
15% off waxgods.com use code: manic15
10% off toplabel.com use code: Manic10
Steve96 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 04-24-2016, 05:27 AM   #4
Junior Member
 
Join Date: Apr 2016
Location: Cape Coral
Region: Florida
Posts: 22
Quote:
Originally Posted by Steve96 View Post
The trans in an 04 is one of the better automatic transmissions to have in a 99-04 Mustang. Its actually "beefed" up from the factory. They can handle a little more HP. I cant remember exactly what was upgraded on them, but Im sure someone will chime in. I want to say IIRC that the trans can hold more like 550-600 hp if in good condition. The 2v engine on the other hand is a time bomb over 450 whp and needs a forged roatating assembly.

Sent from my SM-G920P using Mustang Evolution mobile app


550-600 that is a lot on stock parts I never heard that much safely but I have heard of people having that but then they end up grenadine there transmission
Fitzy_2v is offline   Reply With Quote
Old 04-24-2016, 06:04 AM   #5
Registered Member
Regular
 
Mile high JDF's Avatar
 
Join Date: Jun 2011
Location: Thronton
Region: Colorado
Posts: 5,989
Quote:
Originally Posted by Fitzy_2v View Post
550-600 that is a lot on stock parts I never heard that much safely but I have heard of people having that but then they end up grenadine there transmission
The 04s got the 4R75W which is quite strong, Steve's info is correct. A simple convertor swap can turn it into a pretty nasty setup. But as with everything, previous maintenance and abuse will play a big factor into transmission life.
__________________
Sold - Black 2000 Mustang GT, gone but definitely not forgotten
- Silver 2007 Corvette
Current - DHG 2001 Bullitt
Mile high JDF is offline   Reply With Quote
Old 04-24-2016, 06:05 AM   #6
Junior Member
 
Join Date: Apr 2016
Location: Cape Coral
Region: Florida
Posts: 22
Quote:
Originally Posted by Mile high JDF View Post
The 04s got the 4R75W which is quite strong, Steve's info is correct. A simple convertor swap can turn it into a pretty nasty setup. But as with everything, precious maintenance and abuse will play a big factor into transmission life.


Wow I guess it's time to turn up the boost then. I have a 4r70w
Fitzy_2v is offline   Reply With Quote
Old 04-24-2016, 06:12 AM   #7
Registered Member
Regular
 
Mile high JDF's Avatar
 
Join Date: Jun 2011
Location: Thronton
Region: Colorado
Posts: 5,989
Quote:
Originally Posted by Fitzy_2v View Post
Wow I guess it's time to turn up the boost then. I have a 4r70w
The 4R70W takes a little more work (J-mod) to handle decent power, but the engine rods will let go before the trans does.
__________________
Sold - Black 2000 Mustang GT, gone but definitely not forgotten
- Silver 2007 Corvette
Current - DHG 2001 Bullitt
Mile high JDF is offline   Reply With Quote
Old 04-24-2016, 06:14 AM   #8
Junior Member
 
Join Date: Apr 2016
Location: Cape Coral
Region: Florida
Posts: 22
Quote:
Originally Posted by Mile high JDF View Post
The 4R70W takes a little more work (J-mod) to handle decent power, but the engine rods will let go before the trans does.


What could I do to get up to 500 horsepower short of a whole monster performance rebuild kit.
Fitzy_2v is offline   Reply With Quote
Old 04-24-2016, 06:15 AM   #9
Registered Member
Regular
 
Mile high JDF's Avatar
 
Join Date: Jun 2011
Location: Thronton
Region: Colorado
Posts: 5,989
Quote:
Originally Posted by Fitzy_2v View Post
What could I do to get up to 500 horsepower short of a whole monster performance rebuild kit.
Out of the trans? Or the engine?
__________________
Sold - Black 2000 Mustang GT, gone but definitely not forgotten
- Silver 2007 Corvette
Current - DHG 2001 Bullitt
Mile high JDF is offline   Reply With Quote
Old 04-24-2016, 06:15 AM   #10
Junior Member
 
Join Date: Apr 2016
Location: Cape Coral
Region: Florida
Posts: 22
Quote:
Originally Posted by Mile high JDF View Post
Out of the trans? Or the engine?


The transmission
Fitzy_2v is offline   Reply With Quote
Old 04-24-2016, 06:17 AM   #11
Registered Member
Regular
 
Mile high JDF's Avatar
 
Join Date: Jun 2011
Location: Thronton
Region: Colorado
Posts: 5,989
J-mod and a torque convertor
__________________
Sold - Black 2000 Mustang GT, gone but definitely not forgotten
- Silver 2007 Corvette
Current - DHG 2001 Bullitt
Mile high JDF is offline   Reply With Quote
Old 04-24-2016, 12:55 PM   #12
Registered Member
Regular
 
Join Date: Mar 2013
Location: Salinas
Region: California
Posts: 7,411
Ford states that the 4R70W can handle 506 ft-lbs of torque. There has been speculation that the "70" in 4R70W can be multiplied by 10, and that is the torque handling capacity (700 ft-lbs). The more likely scenario is, that 506 ft-lbs, converted to Newton Meters, is 686 N-M, which can be rounded up to 700.
Transmissions are generally rated for their torque handling capacity, rather than horsepower. Torque is the component in "power" that is most likely to break things.
straybullitt is offline   Reply With Quote
Old 04-24-2016, 12:57 PM   #13
Junior Member
 
Join Date: Apr 2016
Location: Cape Coral
Region: Florida
Posts: 22
Quote:
Originally Posted by straybullitt View Post
Ford states that the 4R70W can handle 506 ft-lbs of torque. There has been speculation that the "70" in 4R70W can be multiplied by 10, and that is the torque handling capacity (700 ft-lbs). The more likely scenario is, that 506 ft-lbs, converted to Newton Meters, is 686 N-M, which can be rounded up to 700.

Transmissions are generally rated for their torque handling capacity, rather than horsepower. Torque is the component in "power" that is most likely to break things.


Wow so what you are saying is my stock 03 4r70w can handle up to 506 ft-lbs of torque
Fitzy_2v is offline   Reply With Quote
Old 04-24-2016, 01:01 PM   #14
Registered Member
Regular
 
Join Date: Mar 2013
Location: Salinas
Region: California
Posts: 7,411
Yes. 506 ft-lbs.
That's what Ford says.
straybullitt is offline   Reply With Quote
Old 04-24-2016, 05:53 PM   #15
Registered Member
Regular
 
Join Date: Oct 2014
Location: B.C
Region: Canada
Posts: 21
Thanks everyone for the data. Would anyone also have any info on CrankHP to RWHP conversion of an Automatic? Is it 15% like a manual or would it be more?
__________________
2006 MUSTANG GT
KNIGHT4000 is offline   Reply With Quote
Old 04-24-2016, 07:40 PM   #16
Registered Member
Regular
 
Steve96's Avatar
 
Join Date: Jul 2013
Location: Waterford
Region: Michigan
Posts: 2,386
Quote:
Originally Posted by KNIGHT4000 View Post
Thanks everyone for the data. Would anyone also have any info on CrankHP to RWHP conversion of an Automatic? Is it 15% like a manual or would it be more?
Its a little higher % with the autos, I would have to look it up but I want to say its closer to 18-20% or so. Somewhere around there. I could be thinking of another car now that I think more about it, lol. Google it and Im sure you will find it eventually

Sent from my SM-G920P using Mustang Evolution mobile app
__________________
1996 GT
2003 GT
Follow on Instagram @manicmustangs
Follow on Instagram @steviesstangs
15% off waxgods.com use code: manic15
10% off toplabel.com use code: Manic10
Steve96 is offline   Reply With Quote
Old 04-24-2016, 08:46 PM   #17
Registered Member
Regular
 
Join Date: Mar 2013
Location: Salinas
Region: California
Posts: 7,411
It varies a lot from vehicle to vehicle, but Steve's estimate is probably pretty close... A few percent more than a manual transmission.
I've heard that Corvettes can break into the low 20%'s. I think that my truck is about a 25% loss!
straybullitt is offline   Reply With Quote
Old 04-24-2016, 09:14 PM   #18
Registered Member
Regular
 
Join Date: Oct 2014
Location: B.C
Region: Canada
Posts: 21
@Steve96 and straybullitt.
That is something that I was wondering, if it might differ from vehicle to vehicle type. The one stock dyno number I found on a 2000 GT is shown here by American Muscle, and it seems its just 15% loss on an Automatic.
I'm curious if the solid rear axle on that generation might help putting the power down better compared to an Automatic Corvette or other cars with IRS? Then again I'm just speculating.
__________________
2006 MUSTANG GT
KNIGHT4000 is offline   Reply With Quote
Old 04-25-2016, 12:17 AM   #19
Registered Member
Regular
 
Steve96's Avatar
 
Join Date: Jul 2013
Location: Waterford
Region: Michigan
Posts: 2,386
Quote:
Originally Posted by KNIGHT4000 View Post
@Steve96 and straybullitt.
That is something that I was wondering, if it might differ from vehicle to vehicle type. The one stock dyno number I found on a 2000 GT is shown here by American Muscle, and it seems its just 15% loss on an Automatic.
I'm curious if the solid rear axle on that generation might help putting the power down better compared to an Automatic Corvette or other cars with IRS? Then again I'm just speculating.
It could be that. Variations from car to car of the same manufacturer too Im sure. Look at some dyno numbers from when the Coyote 5.0s came out, there is variation, not a ton but I have seen them 2%-3% different in rwhp. There were some making close to 400 rwhp but they were rated at 412 flywheel hp, so they would be a lower % obviously to the same car the same day on the same dyno making 390 rwhp rated at 412 flywheel hp. I know you know that just thought Id throw it out there as an example, those numbers are fairly accurate from memory and I think they were both manuals. I cant think of an actual manual vs auto comparison I have seen on anything really. Usually its just a % put out there by the manufacturer which Im sure can vary from car to car. I know the kind of dyno used is a factor on all those numbers anyway. The only way to really know what your car is making is to get it on a dyno and see, then you can figure your actual % of loss from the flywheel. I dont want to know how miniscule either of my cars are rwhp wise, ha.

Sent from my SM-G920P using Mustang Evolution mobile app
__________________
1996 GT
2003 GT
Follow on Instagram @manicmustangs
Follow on Instagram @steviesstangs
15% off waxgods.com use code: manic15
10% off toplabel.com use code: Manic10
Steve96 is offline   Reply With Quote
Old 04-25-2016, 04:47 AM   #20
Registered Member
Regular
 
Join Date: Oct 2014
Location: B.C
Region: Canada
Posts: 21
Quote:
Originally Posted by Steve96 View Post
It could be that. Variations from car to car of the same manufacturer too Im sure. Look at some dyno numbers from when the Coyote 5.0s came out, there is variation, not a ton but I have seen them 2%-3% different in rwhp. There were some making close to 400 rwhp but they were rated at 412 flywheel hp, so they would be a lower % obviously to the same car the same day on the same dyno making 390 rwhp rated at 412 flywheel hp. I know you know that just thought Id throw it out there as an example, those numbers are fairly accurate from memory and I think they were both manuals. I cant think of an actual manual vs auto comparison I have seen on anything really. Usually its just a % put out there by the manufacturer which Im sure can vary from car to car. I know the kind of dyno used is a factor on all those numbers anyway. The only way to really know what your car is making is to get it on a dyno and see, then you can figure your actual % of loss from the flywheel. I dont want to know how miniscule either of my cars are rwhp wise, ha.

Sent from my SM-G920P using Mustang Evolution mobile app
Interesting thing is, this Dyno test by LMR has only 3 bolt ons and a stock tune at the beginning and makes a tiny bit more HP than the AM Test car after Bolt ons and a Tune. The LMR GT is a manual, but on the other hand the power difference could be from the Bolt on Brands. Additionally to a Manual vs Automatic dyno comparison on averages of the same model, it would be great to see a database of Testing the most popular Catbacks, Mid-Pipes,CAI and header Brands on a Dyno against each other. Some kind of a HP/Torque consumer report.

Oh I definitely know what you mean. haha. While I would do a Dyno run if there would be one within or near my city, a part of me doesn't want to see the very small possibility that after all the $ on Bolt Ons and Bama Tune, I would only make 30RWHP more.
Granted, I have smoked a couple of newer stock V8s at the traffic lights that were 3-4 times more expensive as my car, but they where over a 1000 pounds heavier and manuals. So if it was driver error on their part, I was just lucky.

__________________
2006 MUSTANG GT
KNIGHT4000 is offline   Reply With Quote
Old 04-25-2016, 02:41 PM   #21
Staff
Regular
Staff
 
scottydsntknow's Avatar
 
Join Date: Apr 2013
Location: JB MDL
Region: New Jersey
Posts: 16,587
The Marauder guys have found the safe limit to the 4R70W is right around 500ft lbs. The 04 GT and Mach autos (and some late run 03s) got the 4R75W which is way stronger. The limit of that trans is the 23 spline stub shaft which starts to get sketch in the 650ft lb range.

Also screw Monster transmission. If you are going to have a built one done get Dan at Silverfox transmissions to do one for you. For a converter... PI, Circle D are 2 of the big names. Then there is Freakshow if you are on a budget.

You are lucky to have an 04 auto honestly... It is by FAR the most capable car transmssion Ford ever used until the 6R80.

Sent from my LG-D801 using Mustang Evolution mobile app
__________________
2000 Mustang GT Steeda #0048

Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.
scottydsntknow is offline   Reply With Quote
Old 04-26-2016, 12:26 AM   #22
Registered Member
Regular
 
Join Date: Oct 2014
Location: B.C
Region: Canada
Posts: 21
Quote:
Originally Posted by scottydsntknow View Post
The Marauder guys have found the safe limit to the 4R70W is right around 500ft lbs. The 04 GT and Mach autos (and some late run 03s) got the 4R75W which is way stronger. The limit of that trans is the 23 spline stub shaft which starts to get sketch in the 650ft lb range.

Also screw Monster transmission. If you are going to have a built one done get Dan at Silverfox transmissions to do one for you. For a converter... PI, Circle D are 2 of the big names. Then there is Freakshow if you are on a budget.

You are lucky to have an 04 auto honestly... It is by FAR the most capable car transmssion Ford ever used until the 6R80.

Sent from my LG-D801 using Mustang Evolution mobile app
Thank you for the info. I wasn't aware that the Automatic on my 04 was such good quality. I simply assumed it would be similar in quality to the GM Automatics on the 2001/02 Camaro SS, C5s and Ws6s.
__________________
2006 MUSTANG GT
KNIGHT4000 is offline   Reply With Quote
Old 05-02-2016, 02:06 AM   #23
Registered Member
Regular
 
phatspeed7x's Avatar
 
Join Date: Feb 2015
Location: Pengilly
Region: Minnesota
Posts: 582
My 2004 GT has the manual transmission. Last year at the summer nationals I put down 250rwhp with only minor bolt ons (intake, exhaust, throttle body and plenum, factory tune with a tank of only 87 octane)

https://youtu.be/_M74OffhdB0

Now I have the race tune for 91 octane and the car seems more peppy. Can't wait for my cams to get here.

Sent from my LG-H900 using Tapatalk
__________________
~2004 GT with Bolt ons~
phatspeed7x is offline   Reply With Quote
Old 05-02-2016, 03:05 AM   #24
Registered Member
Regular
 
Eturner's Avatar
 
Join Date: Aug 2011
Region: Michigan
Posts: 3,257
Automatic Crank HP-RWHP conversion and max HP limit

Quote:
Originally Posted by phatspeed7x View Post
My 2004 GT has the manual transmission. Last year at the summer nationals I put down 250rwhp with only minor bolt ons (intake, exhaust, throttle body and plenum, factory tune with a tank of only 87 octane)

https://youtu.be/_M74OffhdB0

Now I have the race tune for 91 octane and the car seems more peppy. Can't wait for my cams to get here.

Sent from my LG-H900 using Tapatalk

When your talking intake and plenum, are you talking CAI/upper plenum?.. Or the Whole Intake manifold?.. And what exactly have you done to the exhaust?.. Just curious!..


Sent from the One and Only ME!..🍻
Eturner is offline   Reply With Quote
Old 05-02-2016, 03:20 AM   #25
Registered Member
Regular
 
phatspeed7x's Avatar
 
Join Date: Feb 2015
Location: Pengilly
Region: Minnesota
Posts: 582
Quote:
Originally Posted by Eturner View Post
When your talking intake and plenum, are you talking CAI/upper plenum?.. Or the Whole Intake manifold?.. And what exactly have you done to the exhaust?.. Just curious!..


Sent from the One and Only ME!..🍻
Airaid cold air intake
SVE 75mm throttle body and plenum.
Stock PI intake.
Stock manifolds.
Pypes off-road H pipe.
Flowmaster Super 10 series mufflers.

Sent from my LG-H900 using Tapatalk
__________________
~2004 GT with Bolt ons~
phatspeed7x is offline   Reply With Quote
Old 05-02-2016, 03:49 AM   #26
Registered Member
Regular
 
Eturner's Avatar
 
Join Date: Aug 2011
Region: Michigan
Posts: 3,257
Quote:
Originally Posted by phatspeed7x View Post
Airaid cold air intake
SVE 75mm throttle body and plenum.
Stock PI intake.
Stock manifolds.
Pypes off-road H pipe.
Flowmaster Super 10 series mufflers.

Sent from my LG-H900 using Tapatalk

Nice. I've got the TrickFlow Intake mani. With 75mm TB!.. UD Pullies, BBK Tuned Headers, Pypes OR X-pipe, CherryBomb Vortex cat back!.. And a performance 93 tune!.. Never had my car on a dyno though!..


Sent from the One and Only ME!..🍻
Eturner is offline   Reply With Quote
Old 05-10-2016, 06:45 PM   #27
Registered Member
Regular
 
toneman's Avatar
 
Join Date: Jun 2012
Region: Michigan
Posts: 51
I got a 99 Mustang Gt convertible 5 speed stick with every bolt on you can do. The exhaust is full length headers into an off-road X-pipe with three chamber Flowmaster mufflers. Crower stage 2 cams were put in by Alternative Auto in Chesterfield Michigan and she put down 295 rwhp with 305 foot pounds of torque. That's about roughly all you can get with a 93 octane tune out of a 4.6 2valve with bolt on's and cams. The car runs much stronger than the numbers would suggest. I'm hungry for more power but I'm not doing anymore to this car. It's got a nice rumpy idle and it's fun to cruise in. Hope this helps!


Sent from my iPhone using Mustang Evolution
toneman is offline   Reply With Quote
Old 05-17-2016, 10:43 PM   #28
Registered Member
Regular
 
alecas447's Avatar
 
Join Date: Nov 2014
Location: miami
Region: Florida
Posts: 1,018
Quote:
Originally Posted by KNIGHT4000 View Post
Hi Everyone. Thought I would want to get more educated on information about the stock Automatic of my 04. From what I read, the conversion of Crank HP to RWHP would be a loss of 15% on a manual. What would be the % loss of an Automatic?

Furthermore, what would be the MAX RWHP that a stock Automatic can take on the New Edge?

Thanks

18-20% for auto


Sent from my iPhone using Mustang Evolution

Mac o/r H pipe. Flow master super 44s. Accufab 70mm throttle body. Pro comp intake manifold. MSD coils
alecas447 is offline   Reply With Quote
Reply

Lower Navigation
Go Back   Mustang Evolution > 1979-2015 Mustang GT || Tech and Talk > 1996-2004 Mustang GT

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
non automatic headlights/automatic turn off silverskoundrel General Mustang Discussion 11 09-07-2013 10:13 AM
Automatic to manual conversion Datstangboi 1996-2004 Mustang GT 2 07-23-2013 09:56 PM
Automatic to 5 speed conversion 03fastblack 1996-2004 Mustang GT 5 02-23-2012 11:44 AM
Think 55mph speed limit is too slow? Apparently these kids for GA do to. Zim The Bar 27 03-15-2006 06:34 PM
Got pulled over again.... for driving the speed limit? WhiteStang99 The Bar 28 06-16-2005 01:42 PM

» Like Us On Facebook



01:51 PM


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0

MustangEvolution.com is in no way associated with or endorsed by Ford Motor Company.