Increasing Torque..

[HedgehogFromHell]

I know the old phrase of "BHP Sells cars, Torque wins races" but is there any way to bias towards torque?

I'm running a Ford Focus RS Mk2, it's been remapped to 340bhp and 369lb/ft (501Nm) and is running a turbo back decat Miltek, Mountune airbox system with K&N Filter. I've been on the track a fair few times and just wondering if it's possible to bias back some BHP in order to increase my torque figures?

PH Masses... Enlighten me!

[stevesingo]

There is a direct relationship between torque and power.

HP= torque (lb/ft)/5252 X RPM

Tq= HP/RPM x5252

Example,

If you produce 300lb/ft @3000rpm-6000rpm you have 300/5252x3000=171hp @3000rpm and 300/5252x6000=342hp@6000rpm

and add 50lb/ft you will still see an increase in power.

you will have 300/5252x3000=199HP @3000rpm and 350/5252x6000=399hp @6000rpm

[HedgehogFromHell]

stevesingo said:

There is a direct relationship between torque and power.

HP= torque (lb/ft)/5252 X RPM

Tq= HP/RPM x5252

Example,

If you produce 300lb/ft @3000rpm-6000rpm you have 300/5252x3000=171hp @3000rpm and 300/5252x6000=342hp@6000rpm

and add 50lb/ft you will still see an increase in power.

you will have 300/5252x3000=199HP @3000rpm and 350/5252x6000=399hp @6000rpm

Ah this is fair enough then, I was thinking that there may be something I'm missing in relation to Bhp/lb/Ft... I thank you )

[VHPD]

Some interesting reading on intake trumpet length and how it affects torque here

http://www.emeraldm3d.com/articles/emr-adj-length-...

[HedgehogFromHell]

VHPD said:

Some interesting reading on intake trumpet length and how it affects torque here

http://www.emeraldm3d.com/articles/emr-adj-length-...

That sort of article is something truly special good work there!! I've enjoyed reading it but TB cant be used on a F/I car, however, I shall present it to the tuner to see what he thinks!

[The Black Flash]

HedgehogFromHell said:

I know the old phrase of "BHP Sells cars, Torque wins races" but is there any way to bias towards torque?

I'm running a Ford Focus RS Mk2, it's been remapped to 340bhp and 369lb/ft (501Nm) and is running a turbo back decat Miltek, Mountune airbox system with K&N Filter. I've been on the track a fair few times and just wondering if it's possible to bias back some BHP in order to increase my torque figures?

PH Masses... Enlighten me!

That old phrase is wrong BTW. As the previous poster has pointed out, it's not a case of torque or power, you can't take from one and give to the other.

Why do you want to increase your torque figure, out of interest?

[deeen]

Change the diff?

[HedgehogFromHell]

The Black Flash said:

That old phrase is wrong BTW. As the previous poster has pointed out, it's not a case of torque or power, you can't take from one and give to the other.

Why do you want to increase your torque figure, out of interest?

I prefer having more shove out of corners on track, but didnt really want a XXXBhp "pub figures' car for the pleasure

[HedgehogFromHell]

deeen said:

Change the diff?

Sorry if i dont get the meaning behind your post, the diff is fine, no issues with putting the power down. Do you mean go for a full lockup diff over an ATB?

[deeen]

HedgehogFromHell said:

deeen said:

Change the diff?

Sorry if i dont get the meaning behind your post, the diff is fine, no issues with putting the power down. Do you mean go for a full lockup diff over an ATB?

I mean the torque at the wheels is proportional to the gearing, change down a gear you get more torque at the wheels for a given RPM, change the diff so it's lower geared, more torque at the wheels, more shove out of corners, but possibly a lower top speed of course.

[HedgehogFromHell]

deeen said:

I mean the torque at the wheels is proportional to the gearing, change down a gear you get more torque at the wheels for a given RPM, change the diff so it's lower geared, more torque at the wheels.

Excuse ignorance but wouldn't that be change the gearbox as the diff sends power out at the final drive ratio does it not? Thats how it works on our tanks, so that's how i base my knowledge for this thread!!

[VHPD]

HedgehogFromHell said:

deeen said:

I mean the torque at the wheels is proportional to the gearing, change down a gear you get more torque at the wheels for a given RPM, change the diff so it's lower geared, more torque at the wheels.

Excuse ignorance but wouldn't that be change the gearbox as the diff sends power out at the final drive ratio does it not? Thats how it works on our tanks, so that's how i base my knowledge for this thread!!

A smaller diameter drive wheels/tyres would have a similar effect. Easier to change when back on the road too

[deeen]

HedgehogFromHell said:

Excuse ignorance but wouldn't that be change the gearbox as the diff sends power out at the final drive ratio does it not? Thats how it works on our tanks, so that's how i base my knowledge for this thread!!

Yes correct, so if you change the diff for one with a different final drive ratio, it has the effect of lowering (or raising) all the gears, no need to change the gearbox if that is the effect you want. Agreed with VPHD, smaller overall diameter wheel/tyre combo would do the same job, just make sure smaller wheels fit over the brakes.

Edited by deeen on Friday 23 December 22:32

[HedgehogFromHell]

VHPD said:

A smaller diameter drive wheels/tyres would have a similar effect. Easier to change when back on the road too

Cool, i've been looking at getting some 18" Compomotives with sticky rubber. Am I right to say that smaller dia = less braking power, faster acceleration??

[HedgehogFromHell]

One quick one, anyone have any idea about the decat? I.e would putting in a Cat help with generating shorter spool times? Or is the age old saying of "On a turbocharged car, no exhaust is better than a catted exhaust" on to a winner?

Cheers guys, a bit of food for thought. My daily is getting re-rolled into a semi-track toy over spring and whilst i'm away on tour in Afghan so thank you for your input

Edited by HedgehogFromHell on Friday 23 December 22:33

Edited by HedgehogFromHell on Friday 23 December 22:34

[The Black Flash]

HedgehogFromHell said:

I prefer having more shove out of corners on track, but didnt really want a XXXBhp "pub figures' car for the pleasure

To increase "shove" (i.e. torque at the wheels), you either reduce gearing, or increase engine torque. Short of fitting a larger capacity engine or diesel, you're not going to be able to increase torque without increasing power.

[powerstroke]

HedgehogFromHell said:

Excuse ignorance but wouldn't that be change the gearbox as the diff sends power out at the final drive ratio does it not? Thats how it works on our tanks, so that's how i base my knowledge for this thread!!

I think he means diff gearing ie the final drive ratio , if your gearing isnt optimum then you arnt making the best of the engines power so say perhaps if you never reach maximum revs in top gear you might get a benifit from lower overall gearing or a difernt gear box with closer ratios ....

[VHPD]

HedgehogFromHell said:

whilst i'm away on tour in Afghan so thank you for your input

And thank you for your input in afghan

[HedgehogFromHell]

VHPD said:

And thank you for your input in afghan

Cheers chief, means a lot here's to hoping for a sorted toy when i get home

[VHPD]

The Black Flash said:

To increase "shove" (i.e. torque at the wheels), you either reduce gearing, or increase engine torque. Short of fitting a larger capacity engine or diesel, you're not going to be able to increase torque without increasing power.

On TB's or carbs it is possible to change the torque curve by changing the induction length.
You can have higher low rev torque which will make it quicker out of the bends but this will usually compromise the top end BHP

http://www.emeraldm3d.com/articles/emr-adj-length-...