Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC General > Proven Power Bragging

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Closed Thread
 
Thread Tools Display Modes
Old 08-04-2007, 11:44 AM   #1
Dyno Flash
Vendor
 
Member#: 73568
Join Date: Oct 2004
Location: Stamford, CT
Vehicle:
'05 STI 11.1 @ 127
03 Evo 8 9.5 @ 149

Default Sexy Smooth Stage I '07 STI - Ecutek Tuned

This car really pleased me. I am really learning more and more on these amazing 07 STI ecus each time and this car really ran in a flawless manner on the road, the seemless and smooth progression of boost and tq was OEM like in feel and really made the car a blast to drive.

Here the air temps are off the charts with intense summer heat so I think the power number is down a bit from what we could expect on a cooler day. It was 93 degrees in the dyno room - I ran this number uncorrected as I was impressed how much power it was making in that heat with no adjustment - the smoothing is also set to zero as the car attacked the rollers in a nearly seemlessly smooth turbine like manner. The a/f graph was ideally smooth and contored to the V/E needs of the car. A car I was very happy with indeed.

Mods were HKS 3" catlless Exhuast - Helix upipe

Ecutek Tune by Dyno Flash

* Registered users of the site do not see these ads.
Dyno Flash is offline  
Sponsored Links
* Registered users of the site do not see these ads.
Old 08-04-2007, 11:47 AM   #2
boundy3
Scooby Specialist
 
Member#: 54598
Join Date: Feb 2004
Chapter/Region: South East
Location: Orlando
Vehicle:
2004 WRX Sedan
WR Blue Pearl #68 STX

Default

nice torque.

One question, is there a specific reason the owner swapped out the UP, do you really see any gains on the sti, from your experience, by swapping the UP, does it spool quicker?
boundy3 is offline  
Old 08-04-2007, 11:54 AM   #3
Dyno Flash
Vendor
 
Member#: 73568
Join Date: Oct 2004
Location: Stamford, CT
Vehicle:
'05 STI 11.1 @ 127
03 Evo 8 9.5 @ 149

Default

I have never done A - B testing on the stock 07 upipe

The stock unit has no cat - however it is somewhat restrictive and a aftermaket one is going to free up air flow

One day we will have to do a A - B test to quantify any gains

With the stock air box and TGV's in place I am not sure the upipe is contributing all that much - maybe as the customer progresses in his stages the upipe mod will reap more benefits
Dyno Flash is offline  
Old 08-04-2007, 11:56 AM   #4
Dyno Flash
Vendor
 
Member#: 73568
Join Date: Oct 2004
Location: Stamford, CT
Vehicle:
'05 STI 11.1 @ 127
03 Evo 8 9.5 @ 149

Default

I should add that this was accomplished with a peak boost level of 19.1 max tapering to red line near 15.

The TQ gains are produced through carefull AVCS mapping and timing and fuel tuning

Al
Dyno Flash is offline  
Old 08-04-2007, 12:04 PM   #5
PaulRex
Scooby Guru
 
Member#: 12454
Join Date: Nov 2001
Chapter/Region: Tri-State
Location: Vermont
Vehicle:
10 Toyota Taco
K8 SV650SF

Default

man that car has huge area under the curve.. and for dropping down to 15psi at redline thats good power up top
PaulRex is offline  
Old 08-04-2007, 12:14 PM   #6
crucifudge
Scooby Newbie
 
Member#: 67061
Join Date: Jul 2004
Default

you could get lost in the torque curve
crucifudge is offline  
Old 08-04-2007, 12:22 PM   #7
darknightohio
Scooby Specialist
 
Member#: 50523
Join Date: Dec 2003
Chapter/Region: MWSOC
Location: Toledo
Vehicle:
2023 GR86
Gray

Default

Using HKS downpipe?
darknightohio is offline  
Old 08-04-2007, 12:39 PM   #8
Equilibrium Tuning
Former Vendor
 
Member#: 26933
Join Date: Oct 2002
Chapter/Region: BAIC
Location: Fairfield, CA
Vehicle:
2006 STI
CGM

Default

Looks pretty good Al. Looks like torque dips a bit between 3800-4800 RPM, but no big deal.

What does a stock 07 STI put down on your new dyno?

-- Ed
Equilibrium Tuning is offline  
Old 08-04-2007, 01:10 PM   #9
AZScoobie
Scooby Guru
 
Member#: 8785
Join Date: Jul 2001
Chapter/Region: SWIC
Vehicle:
02 c_turner@ix.
netcom.com

Default

Yeah Ed. Def knock correction going on around 3800.

Clark
AZScoobie is offline  
Old 08-04-2007, 01:13 PM   #10
Dyno Flash
Vendor
 
Member#: 73568
Join Date: Oct 2004
Location: Stamford, CT
Vehicle:
'05 STI 11.1 @ 127
03 Evo 8 9.5 @ 149

Default

We did a bone stock '07 which made 250 and after tuning it made 270 - however - it is the ICS loaner car and I later discovered that the young lady we had lent it to had put 87 octane fuel in it LOL!

Honestly, I dont see many bone stock cars here.

Our dyno is very typical of any other Dyno Jet as far as power band does

BTW - there is no dip in the TQ - what you are seeing is the boost level being adjusted lower through that area of the power band so that in 6th gear the boost is not creeping higher.

The knock correction is linear and timing smooth and progressive throughout.

Al
Dyno Flash is offline  
Old 08-04-2007, 01:15 PM   #11
Dyno Flash
Vendor
 
Member#: 73568
Join Date: Oct 2004
Location: Stamford, CT
Vehicle:
'05 STI 11.1 @ 127
03 Evo 8 9.5 @ 149

Default

Quote:
Originally Posted by AZScoobie View Post
Yeah Ed. Def knock correction going on around 3800.

Clark
Wrong - see above post the boost was tapered down in that area of the map to help prevent boost creeping in 5th and 6th gear. I try to keep the boost under control at all times which usually means running lower WGDC in that area of the map.

Sometimes you sound to me like a real idiot when you pontificate on something you dont have hard facts on.

Lucky for me I know that you have a clue but in this case you are really speaking without the benefit of any data log or information.

The delta dash logs showed no knock retard what so ever both on the dyno and on the road in 4th, 5th and 6th gear testing. Of course your 3rd hand impression, made without the benefit of any data logging or data, is proably very accurate - lol.

I think you should realize that no car leaves my hands without several dozen carfully loged dyno runs and a very careful road test. Simply put, I have been doing this just as long as you have and you should already know that I do not produce half assed work that is pulling timing or having knock correction issues.

AL

Last edited by Dyno Flash; 08-04-2007 at 01:37 PM.
Dyno Flash is offline  
Old 08-04-2007, 03:10 PM   #12
AZScoobie
Scooby Guru
 
Member#: 8785
Join Date: Jul 2001
Chapter/Region: SWIC
Vehicle:
02 c_turner@ix.
netcom.com

Default

I like how two tuners noticed the dip in power. Yet you only chose to come back at me. That tells me and the community alot Al.

If I notice something I point it out. Its my nature to do so. That car is dipping in the 3500 to 4000 rpm range. Its also very jagged. Maybe its my 12 years of experience reading Dynojet curves that led me to see that?

CLark
AZScoobie is offline  
Old 08-04-2007, 03:14 PM   #13
SubieFiesta
Scooby Newbie
 
Member#: 149426
Join Date: May 2007
Vehicle:
2002 Subaru WRX
2005 Subaru STi & 2000 RS

Default

Quote:
Originally Posted by AZScoobie View Post
I like how two tuners noticed the dip in power. Yet you only chose to come back at me. That tells me and the community alot Al.

If I notice something I point it out. Its my nature to do so. That car is dipping in the 3500 to 4000 rpm range. Its also very jagged. Maybe its my 12 years of experience reading Dynojet curves that led me to see that?

CLark
I agree. The dip is not only in the torque but also in the horsepower and as you start to look closely at the sheet the power band does look wavy...dont take it to heart clark..he is running out of excuses on why cars he tunes act certain ways and have certain problems, never him though

Last edited by SubieFiesta; 08-04-2007 at 03:20 PM.
SubieFiesta is offline  
Old 08-04-2007, 03:26 PM   #14
PolarisSnT
Scooby Specialist
 
Member#: 85905
Join Date: Apr 2005
Chapter/Region: Tri-State
Location: Staten Island
Vehicle:
2004 WRX

Default

It has been my experience on the ICS dyno that the correction factor lowers the numbers. So if you ran it 'corrected' the car would be reading lower than what is shown here.

Am I mistaken?
PolarisSnT is offline  
Old 08-04-2007, 03:51 PM   #15
vividwrx13
Scooby Specialist
 
Member#: 66402
Join Date: Jul 2004
Chapter/Region: SWIC
Location: Phoenix,AZ
Vehicle:
2005 STi Ver8
OBP

Default

Quote:
Originally Posted by SubieFiesta View Post
I agree. The dip is not only in the torque but also in the horsepower and as you start to look closely at the sheet the power band does look wavy...dont take it to heart clark..he is running out of excuses on why cars he tunes act certain ways and have certain problems, never him though

x2 al ftl
vividwrx13 is offline  
Old 08-04-2007, 04:22 PM   #16
STi_Man
Scooby Newbie
 
Member#: 79096
Join Date: Jan 2005
Chapter/Region: NESIC
Location: Ayer, MA
Vehicle:
2004 Impreza WRX STi
Black

Default

Nice numbers Al, 07 STI are dam impressive
STi_Man is offline  
Old 08-04-2007, 04:25 PM   #17
SuperSTI
Scooby Specialist
 
Member#: 67182
Join Date: Jul 2004
Vehicle:
2004 Subaru STi
11.0 @ 128mph - 93/Meth

Default

Quote:
Originally Posted by SubieFiesta View Post
I agree. The dip is not only in the torque but also in the horsepower and as you start to look closely at the sheet the power band does look wavy...dont take it to heart clark..he is running out of excuses on why cars he tunes act certain ways and have certain problems, never him though
Quote:
Originally Posted by vividwrx13 View Post
x2 al ftl
x3 ditto.

to people who dont know, graph looks fine. they just look at peak. but we all know better than that. especially dynoflash ex-customers. if i had my boogy board we can go wave jumping on that dynosheet. the dip between 3500rpm and 5000rpm is huge especially the waves afterwards.
SuperSTI is offline  
Old 08-04-2007, 04:50 PM   #18
Dyno Flash
Vendor
 
Member#: 73568
Join Date: Oct 2004
Location: Stamford, CT
Vehicle:
'05 STI 11.1 @ 127
03 Evo 8 9.5 @ 149

Default

The little waves in the sheet are becuase the smoothing is set to zero = no smoothing

With the smoothing on 5 the line would be flater

in 92 degree air temps every correction - STC, SAE, and DIN all raise the power

When the ambient temps are 60 degress or less the corrections lower the numbers

I try and use the correction or lack of correction that best suits the conditions. At 92 the correction is inflating the power so much that I find it overly corrected and prefer to run the car with no correction - heads up so to speak.

If it were in the 70's no doubt the car would have made more power.

The sheet is what it is and it speaks for itself


Al
Dyno Flash is offline  
Old 08-04-2007, 05:13 PM   #19
SuperSTI
Scooby Specialist
 
Member#: 67182
Join Date: Jul 2004
Vehicle:
2004 Subaru STi
11.0 @ 128mph - 93/Meth

Default

Quote:
Originally Posted by Dyno Flash View Post
The little waves in the sheet are becuase the smoothing is set to zero = no smoothing

With the smoothing on 5 the line would be flater

in 92 degree air temps every correction - STC, SAE, and DIN all raise the power

When the ambient temps are 60 degress or less the corrections lower the numbers

I try and use the correction or lack of correction that best suits the conditions. At 92 the correction is inflating the power so much that I find it overly corrected and prefer to run the car with no correction - heads up so to speak.

If it were in the 70's no doubt the car would have made more power.

The sheet is what it is and it speaks for itself


Al
and who wins for best excuse of the year.......AL! YOU ARE OUR WINNER!
SuperSTI is offline  
Old 08-04-2007, 05:15 PM   #20
SubieFiesta
Scooby Newbie
 
Member#: 149426
Join Date: May 2007
Vehicle:
2002 Subaru WRX
2005 Subaru STi & 2000 RS

Default

Quote:
Originally Posted by SuperSTI View Post
and who wins for best excuse of the year.......AL! YOU ARE OUR WINNER!
+10000

Quote:
Originally Posted by Dyno Flash View Post
The little waves in the sheet are becuase the smoothing is set to zero = no smoothing

With the smoothing on 5 the line would be flater

in 92 degree air temps every correction - STC, SAE, and DIN all raise the power

When the ambient temps are 60 degress or less the corrections lower the numbers

I try and use the correction or lack of correction that best suits the conditions. At 92 the correction is inflating the power so much that I find it overly corrected and prefer to run the car with no correction - heads up so to speak.

If it were in the 70's no doubt the car would have made more power.

The sheet is what it is and it speaks for itself


Al
I have had my car on a hand full of different dynos. When the correction is applied the car makes less power. Not more. but I can see why you are trying to convince the public other wise. you are good at selling. question: do you believe the stuff that comes out of your own mouth?
SubieFiesta is offline  
Old 08-04-2007, 05:27 PM   #21
ryantherobot
Scooby Specialist
 
Member#: 129692
Join Date: Oct 2006
Chapter/Region: SCIC
Location: The OC.
Vehicle:
2011 WRX Sedan
Obsidian Black Swirl

Default

nowwwwwwww boy's.
ryantherobot is offline  
Old 08-04-2007, 05:50 PM   #22
Dyno Flash
Vendor
 
Member#: 73568
Join Date: Oct 2004
Location: Stamford, CT
Vehicle:
'05 STI 11.1 @ 127
03 Evo 8 9.5 @ 149

Default

Guys, for those interested I pulled up the customers run file, added a STD correction and put the smoothing on 5. The power did not jump as far as I expected, but it did never the less add on some whp with the correction.

Dyno Flash is offline  
Old 08-04-2007, 06:01 PM   #23
SubieFiesta
Scooby Newbie
 
Member#: 149426
Join Date: May 2007
Vehicle:
2002 Subaru WRX
2005 Subaru STi & 2000 RS

Default

Quote:
Originally Posted by Dyno Flash View Post
Guys, for those interested I pulled up the customers run file, added a STD correction and put the smoothing on 5. The power did not jump as far as I expected, but it did never the less add on some whp with the correction.


lol gee how did i know you were gonna come up with something to say.

I have an old sheet of my car tuned on a dynojet with smoothing at 0 and it is no where near as WAVY as yours. the HP is wavy along with the TQ being wavy. And then theres the dip. geeeeeeee, is the HUGE DIP from the correction factor or maybe the smoothing being at 0. hmmm.
SubieFiesta is offline  
Old 08-04-2007, 06:02 PM   #24
Dyno Flash
Vendor
 
Member#: 73568
Join Date: Oct 2004
Location: Stamford, CT
Vehicle:
'05 STI 11.1 @ 127
03 Evo 8 9.5 @ 149

Default

Quote:
Originally Posted by SubieFiesta View Post
+10000



I have had my car on a hand full of different dynos. When the correction is applied the car makes less power. Not more. but I can see why you are trying to convince the public other wise. you are good at selling. question: do you believe the stuff that comes out of your own mouth?
The correction varies depending on the conditions existing in the dyno cell - e.g. air temps, baromoeter, humidity, etc.

The corrections are standardized and programed into all Dyno Jet dynos all you do is simply choose if you want to use a correction - or run it uncorrected and click on which correction you want

Corrections raise power on hot days - this is not my opinion it is a fact

The correctioin factors were developed to level the playing field for cars tested on different days. However, most of them were developed with large normally aspirated motors in mind. In practice turbo charged cars are able to equalize variations in climatic conditions more effectively than N/A cars so the standard and sae corrections are less relevant IMHO.


You can find more data on this subject for those who are interested here :


http://wahiduddin.net/calc/cf.htm



Dyno Correction Factor and Relative Horsepower


So what's all this correction factor stuff anyway??

The horsepower and torque available from a normally aspirated internal combustion engine are dependent upon the density of the air... higher density means more oxygen molecules and more power... lower density means less oxygen and less power.

The relative horsepower, and the dyno correction factor, allow mathematical calculation of the affects of air density on the wide-open-throttle horsepower and torque. The dyno correction factor is simply the mathematical reciprocal of the relative horsepower value.

What's it good for?

One common use of the dyno correction factor is to standardize the horsepower and torque readings, so that the effects of the ambient temperature and pressure are removed from the readings. By using the dyno correction factor, power and torque readings can be directly compared to the readings taken on some other day, or even taken at some other altitude.

That is, the corrected readings are the same as the result that you would get by taking the car (or engine) to a certain temperature controlled, humidity controlled, pressure controlled dyno shop where they measure "standard" power, based on the carefully controlled temperature, humidity and pressure.

If you take your car to the dyno on a cold day at low altitude, it will make a lot of power. And if you take exactly the same car back to the same dyno on a hot day, it will make less power. But if you take the exact same car to the "standard" dyno (where the temperature, humidity and pressure are all carefully controlled) on those different days, it will always make exactly the same power.

Sometimes you may want to know how much power you are really making on that specific day due to the temperature, humidity and pressure on that day; in that case, you should look at the uncorrected power readings.

But when you want to see how much more power you have solely due to the new headers, or the new cam, then you will find that the corrected power is more useful, since it removes the effects of the temperature, humidity and atmospheric pressure and just shows you how much more (or less) power you have than in your previous tests.

There is no "right" answer... it's simply a matter of how you want to use the information.

If you want to know whether you are going to burn up the tranny with too much power on a cool, humid day, then go to the dyno and look at uncorrected power to see how exactly much power you have under these conditions.

But if you want to compare the effects due to modifications, or you want to compare several different cars at different times, then the corrected readings of the "standard" dyno will be more useful.

How's it calculated?

The Society of Automotive Engineers (SAE) has created a standard method for correcting horsepower and torque readings so that they will seem as if the readings had all been taken at the same "standard" test cell where the air pressure, humidity and air temperature are held constant.

The equation for the dyno correction factor given in SAE J1349 JUN90, converted to pressure in mb, is:






where: cf = the dyno correction factor
Pd = the pressure of the dry air, mb
Tc = ambient temperature, deg C

The pressure of the dry air Pd, is found by subtracting the vapor pressure Pv from the actual air pressure. For more information about pressures and calculation of the vapor pressure, see Air Density and Density Altitude.

The relative horsepower is simply the mathematical reciprocal of the correction factor.



Horsepower and Torque:

Power is the rate at which work is done. When the engine torque is turning the crankshaft and power is being delivered, the resulting horsepower may be expressed as:



which can be simplified as



where: hp = horsepower, hp
t = torque, ft-lbs
rpm = engine speed, revolutions per minute


This is a great formula. Basically it says that if you can keep the same amount of torque, then the more rpm you can turn, the more horsepower you get!

That's why Formula One and CART and IRL engines all turn incredible rpm. The faster the engine turns, the more power it can make (when it's properly tuned to operate at that speed).

Consider for example: a normally aspirated internal combustion engine typically produces about 1 to 1.5 ft-lbs of torque per cubic inch when it is properly tuned to operate at any specific rpm. With a 2 litre (1 litre is about 61 cubic inches) engine, producing 1.5 ft-lbs of torque per cubic inch, you would expect to get about 180 hp at 5200 rpm... but you will get a whopping 415 hp if you can get it to run at 12,000 rpm.

The 3.5 liter IRL engine is reported to produce about 650 hp at 10,700 rpm. That would be about 1.5 ft-lbs per cubic inch.

The Ferrari 3.0 liter Formula One engine is rumored to produce about 860 hp at 18,500 rpm. That would be about 1.33 ft-lbs per cubic inch.

And at the other end of the rpm spectrum, one model of the 360 cubic inch four cylinder Lycoming IO-360 aircraft engine produces 180 hp at 2700 rpm, which is 0.97 ft-lbs per cubic inch.

In general, production automobile engines that have a broad torque band will produce about 0.9 to 1.1 ft-lbs per cubic inch. Highly tuned production engines, such as the Honda S2000 or the Ferrari F50 are in the range of 1.1 to 1.3 ft-lbs per cubic inch. Highly tuned race engines such as NASCAR, IRL and Formula One are often in the range of 1.3 to 1.5 ft-lbs per cubic inch.



Conversion Factors:

To convert to other units, try the DigitalDutch or NIST web sites.



enjoy..

Richard Shelquist
Longmont, Colorado

updated: 18-Oct-2005




Dyno Flash is offline  
Old 08-04-2007, 06:05 PM   #25
SuperSTI
Scooby Specialist
 
Member#: 67182
Join Date: Jul 2004
Vehicle:
2004 Subaru STi
11.0 @ 128mph - 93/Meth

Default

Quote:
Originally Posted by Dyno Flash View Post
The correction varies depending on the conditions existing in the dyno cell - e.g. air temps, baromoeter, humidity, etc.

The corrections are standardized and programed into all Dyno Jet dynos all you do is simply choose if you want to use a correction - or run it uncorrected and click on which correction you want

Corrections raise power on hot days - this is not my opinion it is a fact

The correctioin factors were developed to level the playing field for cars tested on different days. However, most of them were developed with large normally aspirated motors in mind. In practice turbo charged cars are able to equalize variations in climatic conditions more effectively than N/A cars so the standard and sae corrections are less relevant IMHO.


You can find more data on this subject for those who are interested here :


http://wahiduddin.net/calc/cf.htm



Dyno Correction Factor and Relative Horsepower


So what's all this correction factor stuff anyway??

The horsepower and torque available from a normally aspirated internal combustion engine are dependent upon the density of the air... higher density means more oxygen molecules and more power... lower density means less oxygen and less power.

The relative horsepower, and the dyno correction factor, allow mathematical calculation of the affects of air density on the wide-open-throttle horsepower and torque. The dyno correction factor is simply the mathematical reciprocal of the relative horsepower value.

What's it good for?

One common use of the dyno correction factor is to standardize the horsepower and torque readings, so that the effects of the ambient temperature and pressure are removed from the readings. By using the dyno correction factor, power and torque readings can be directly compared to the readings taken on some other day, or even taken at some other altitude.

That is, the corrected readings are the same as the result that you would get by taking the car (or engine) to a certain temperature controlled, humidity controlled, pressure controlled dyno shop where they measure "standard" power, based on the carefully controlled temperature, humidity and pressure.

If you take your car to the dyno on a cold day at low altitude, it will make a lot of power. And if you take exactly the same car back to the same dyno on a hot day, it will make less power. But if you take the exact same car to the "standard" dyno (where the temperature, humidity and pressure are all carefully controlled) on those different days, it will always make exactly the same power.

Sometimes you may want to know how much power you are really making on that specific day due to the temperature, humidity and pressure on that day; in that case, you should look at the uncorrected power readings.

But when you want to see how much more power you have solely due to the new headers, or the new cam, then you will find that the corrected power is more useful, since it removes the effects of the temperature, humidity and atmospheric pressure and just shows you how much more (or less) power you have than in your previous tests.

There is no "right" answer... it's simply a matter of how you want to use the information.

If you want to know whether you are going to burn up the tranny with too much power on a cool, humid day, then go to the dyno and look at uncorrected power to see how exactly much power you have under these conditions.

But if you want to compare the effects due to modifications, or you want to compare several different cars at different times, then the corrected readings of the "standard" dyno will be more useful.

How's it calculated?

The Society of Automotive Engineers (SAE) has created a standard method for correcting horsepower and torque readings so that they will seem as if the readings had all been taken at the same "standard" test cell where the air pressure, humidity and air temperature are held constant.

The equation for the dyno correction factor given in SAE J1349 JUN90, converted to pressure in mb, is:






where: cf = the dyno correction factor
Pd = the pressure of the dry air, mb
Tc = ambient temperature, deg C

The pressure of the dry air Pd, is found by subtracting the vapor pressure Pv from the actual air pressure. For more information about pressures and calculation of the vapor pressure, see Air Density and Density Altitude.

The relative horsepower is simply the mathematical reciprocal of the correction factor.



Horsepower and Torque:

Power is the rate at which work is done. When the engine torque is turning the crankshaft and power is being delivered, the resulting horsepower may be expressed as:



which can be simplified as



where: hp = horsepower, hp
t = torque, ft-lbs
rpm = engine speed, revolutions per minute


This is a great formula. Basically it says that if you can keep the same amount of torque, then the more rpm you can turn, the more horsepower you get!

That's why Formula One and CART and IRL engines all turn incredible rpm. The faster the engine turns, the more power it can make (when it's properly tuned to operate at that speed).

Consider for example: a normally aspirated internal combustion engine typically produces about 1 to 1.5 ft-lbs of torque per cubic inch when it is properly tuned to operate at any specific rpm. With a 2 litre (1 litre is about 61 cubic inches) engine, producing 1.5 ft-lbs of torque per cubic inch, you would expect to get about 180 hp at 5200 rpm... but you will get a whopping 415 hp if you can get it to run at 12,000 rpm.

The 3.5 liter IRL engine is reported to produce about 650 hp at 10,700 rpm. That would be about 1.5 ft-lbs per cubic inch.

The Ferrari 3.0 liter Formula One engine is rumored to produce about 860 hp at 18,500 rpm. That would be about 1.33 ft-lbs per cubic inch.

And at the other end of the rpm spectrum, one model of the 360 cubic inch four cylinder Lycoming IO-360 aircraft engine produces 180 hp at 2700 rpm, which is 0.97 ft-lbs per cubic inch.

In general, production automobile engines that have a broad torque band will produce about 0.9 to 1.1 ft-lbs per cubic inch. Highly tuned production engines, such as the Honda S2000 or the Ferrari F50 are in the range of 1.1 to 1.3 ft-lbs per cubic inch. Highly tuned race engines such as NASCAR, IRL and Formula One are often in the range of 1.3 to 1.5 ft-lbs per cubic inch.



Conversion Factors:

To convert to other units, try the DigitalDutch or NIST web sites.



enjoy..

Richard Shelquist
Longmont, Colorado

updated: 18-Oct-2005






you couldnt answer the question yourself so you had to do a copy and paste!!!!! i just peeeeed myself

you always have an excuse...it amazes me.
SuperSTI is offline  
Closed Thread

Thread Tools
Display Modes

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
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Passion and Power with a Stock '07 STi - Ecutek tuned Dyno Flash Proven Power Bragging 50 08-13-2007 11:00 PM
'07 STI - SPT Cat Back only with Ecutek Tune vs stock Dyno Flash Proven Power Bragging 54 08-09-2007 12:38 PM
'07 STI Stage II + with AP2 Pro Tune Dyno Flash Proven Power Bragging 10 07-25-2007 11:08 AM
'07 STI - 93 octane Stage II AP2 Pro Tune Dyno Flash Proven Power Bragging 34 03-27-2007 10:29 PM
MY06 WRX/STI EcuTek tuning special mpj_becks Bay Area Impreza Club Forum -- BAIC 1 10-16-2005 02:53 AM

All times are GMT -4. The time now is 07:26 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.