How do I set about getting more torque?

Below is my graph from Powerstation, wow notice the flat spot at the top, I think that this has been cured now by the addition of a K&N induction kit (certainly feels better )

 

Ian.
It certainly seems very low for an STi, but how does it feel on the road? Rollers have a funny habit of throwing up completely inconsistent figures. There are so many variables. As such, they such really only be used to get comparisons after you make mods to your car. I would perhaps suggest attending another rolling road event to get a 'second opinion'. If the torque is low on both, then you can try looking for a solution.
Take my car for example. It is the highest powered UK car (std ecu) that has run on PE's rollers

 

It will be directly related to BHP! I think that the formula is Torque = BHP * (RPM/5252) From memory i believe that is the formula??

 

Stef,

Don't mean to steal your thunder But.....

Most powerful uk car on PE's rollers..
286bhp
251 lb/ft

std ecu (hks SuperDrager/Induction/downpipe and hks electronic boost controller at 1.15bar)

Nito
(I know, I know, I have a boost controller but ecu was still std. Amazing the difference 3 psi makes )

 

Stef,

The car feels good on the road, but then I have never been in another STi to compare.

What could I look at to improve the torque figures. Would more boost = more torque, if so what is the easiest and safest way to do this? Is the only way a new ECU, a bit ££££

Ian.
STi II

 

Ian,

Early cars had less torque and bhp anyway so what you are seeing is about right. IIRC early STi's had 240bhp while torque used to be less than bhp on the earlier cars. Bear in mind that uk cars from the same year had 208bhp and 201 lb/ft Torque. Then also take into account the fact that the quoted 240bhp for your model was measured with jap spec 100ron fuel and you can see that your car is about right. Also bear in mind that PS figures are generally much lower than other rolling roads, not that their accuracy is in question just generally more pesimistic while as PE figures are much more optimistic. If you look at the figures from every car you'll see that they register less at PS.

More boost=more power and torque but you have to be careful not to go too mad. Remapped ECU/replacement ECU is one way to do this, other alternatives include an electronic boost controller or even bleed valves. Personally I wouldn't recommend a bleed valve. I use an HKS electronic boost controller and am very pleased with it. If I feel the need for a remap later on the unichip would compliment this mod perfectly since the unichip relies on an external form of boost control. Other owners have also reported good results with the link etc..

Nito

 

Nito, do you run yours with the standard boost cut-out still active? Also, how much is an HKS electronic boost controller and how is it installed?
Cheers

 

Those figures don't look particularly bad considering the boost level you are running.

 

Nito,

You say that the figures look good, however, the STi II should run 275ps, not 240ps. The STi II was the last model to use the older style engine (EJ20G???) before the 280ps of the STi III and above. So do you still think that the figures look okay?

By the way how much is an adjustable boost controller and how safe is it?????

Ian.
STi II

 

You're absolutely right Ian. The first STi came in 92 with 240ps. The second one came in 94 with 260ps. Then in 95 came the STi 2 with 275ps followed by the STi 3 in late 97 with the 280ps engine. Torque for your model is quoted at 32.5kg as oppsed to 33.5kg for the Sti3! I'm not sure how to convert kg-m into Lb/ft. The bhp figures look perfectly healthy and the torque doesn't seem anything to worry about. If you look at my car torque is also reasonably low compared to bhp.

As for Boost controllers, I run an HKS one which costs £465. AFAIC they are perfectly safe running a reasonable amount of boost. As has been said elsewhere though, you have to make sure your car is fuelling ok. UK cars running over rich in any case so shouldn't be any problems there. Also bear in mind that earlier cars had the fuel cut at a lower boost level to later cars. I'm not sure on jap sti's..if you were to go for one it would be a wise move to get a unichip or something to go with it. At this sort of cost you could also get a link which uses the std boost control solenoid.

Iain, I still have my fuel cut active but it's never come in since fitting the boost controller. Previous to this the std car was trying to boost to 1.35bar after fitting exhaust induction and was overboosting even before fitting this! Fuel cut on my car comes in between 1.2 and 1.25bar but it cuts in earlier on some cars. I run my boost controller at 1.15bar. Personally I quite like leaving this arrangement in place. Also the boost controller controls the boost so much better than before...there are no spikes or troughs in the boost curve like there were previous to this and the torque curve is very flat which is apparently desirable! There seem to be a lot of 97> cars running low boost 0.8bar ish and I'll bet that many have a boost restrictor in place which was the suggested (and not a very satisfactory one) fix for the overboost problem. Mine was fitted with one and came back from 1.2bar+ to around 0.75ish. Hence the reason why I bought the EVC and I haven't looked back since. 50K miles and lots of smiles later!

Nito

 

This is the best convert on web:

 

Thanks Eric.

In which case Ian..your car should have 319nm which is 234 Lb/Ft, so not too far out particularly bearing in mind lower octane and Ps rollers.

Nito

out of interest then from STi info & stats...
STi 92-304nm 240ps (223Lb/Ft)(246bhp)
STi 94-309nm 260ps (227Lb/Ft)(256bhp)
STi 2 -319nm 275ps (234Lb/Ft)(270bhp)
STi 3 -280ps (276bhp)some had 329nm(241Lb/Ft and some 343nm(252Lb/Ft)(news to me thought they were all the same this year!)
STi 4 -353nm 280ps (259lb/ft)(276bhp)
STi 5 -As above
STi 6 - ???

 

Just for completeness;

uk cars

MY94-96 201Lb/ft 208bhp
MY 97 214Lb/ft 208bhp
My 98 214Lb/ft 208bhp
My 99 214Lb/ft 215bhp
My 00 As above

Not sure on Prodrive cars
94-96 240bhp? 240 Lb/ft?
97/98 240 bhp 240 Lb/ft
99-00 250bhp? 258Lb/ft

 

Nito.
Your figures aren't on the dyno page so !!!! Anyway, I'll amend it to 'the most powerful UK car with std ecu and no boost controllers'!!!

Ian.
It would seem your figures aren't too far out after all then, but a Unichip wouldn't cost much more than the HKS EVC.

Stef.

 

Nito,

Thanks for the figures, you certainly have done your research?!

Tony,

If there is a particular formula for calculating BHP from Torque, then how come when you look at different cars there does not seem to be a logical link? See the figures below from Powerstation site (please no comments about how conservative the figures are it is just that they are all from the same source):

Ian Yexley 231bhp & 225lb/ft
Martin Cook 238bhp & 225lb/ft
ME 263bhp & 225lb/ft

How can we all have the same torque but different BHP?????

Ian.
STi II

 

Ian

This is because bhp is a factor of both revs and torque levels (at that point in the torque curve). The engines which produce higher bhp manage this by maintaining reasonable torque throughout the rev range (and particularly at high revs). Typically torque levels drop away as the revs rise above 4000 rpm (in road cars); this has a detrimental effect on bhp. Engines with the higher bhp figures must have a flatter torque curve.

D.

 

How gracefully you give up your title Stef

Here's one for the non-believers!! Should be on the dyno page soon. It was taken almost exactly a year ago.

I won't post it on here as It's pretty big but you can view it here; "Please welcome the new most powerful in uk with std ecu champ..."

 

Is it that peak torque is when your engine is doing the best job of turning air and fuel into the forces required to turn your wheels...

Say that is at 5000 revs, beyond that the engine is becoming less efficient at doing the job, but converting more fuel and air at a faster rate, hence the BHP continues to rise...

 

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by Stef:
<B>Your figures aren't on the dyno page so !!!! Anyway, I'll amend it to 'the most powerful UK car with std ecu and no boost controllers'!!!
[/quote]

Not wishing to gloat Stef, but I think I take the title for most powerful UK car at Power Engineering (the graphs will be up soon!)

MY99 UK car with the following modifications:

ScoobySport Back Box
ScoobySport Down Pipe
Magnex Mid-Section (with resonator)
Unifilter RamPod Air Inductor
MRT Cold Air Feed Pipe (replaces the air resonator in offside wing)

271 BHP at 6573rpm
249 lb/ft of torque
1.1 Bar (16ish PSI) maximum boost

Cheers
Andy

 

Are you the one they said would bring balance to the force

Er...be precise Andy Pandy, that would be "most powerful uk car with std ecu and no boost controllers"! :P

However, most powerful UK car with std ecu/internals must go to the Silver Drwagon!