94 replies to this topic

[mcbunny]

i mean even tyre pressure can alter the power figures that are recorded so its very hard for them to be 100% accurate

[Thorney]

Its the issue over wheelspin whichis why we went for the Dyno dynamics rolling road, adding weight to the car to get it to grip will erode any possible accuracey from the run; it will change the tyre performance on the roller, change the % losses to flyhweel etc etc. We strap em down and they stay strapped down.

We've just done another VXR Astra - 199bhp at the wheels, 235bhp at the flywheel - ie bog stock. This road is not wrong.

However, I really really want to get accross that the only number we or anyone else with a dyno can measure is power at the wheels - nothing more.

Oh sure, what I meant was slippage on the rollers will make the power reading meaningless thats all.

We do have gripped rollers and we raise the tyre pressure to 40psi (50psi on all other cars) to address the tyre deformation issue and also to ensure all the cars run with the same tyre pressure so the results compare accurately.

We actually helped out Maha l;ast week with the issue of strapping down VX's onto their dynos (see we are working with everyone on this) but sadly the tuner they picked to use didn't have enouhg cooling and the VXT we used backed off before full power was acheived.

[i need nos]

so is it safe to assume bog standard n/as produce about 120 at the wheel and 145 at fly, as an average figure and with a stage 2 it just irons out the lumpy feel to give a better feel of drive but not nessesarily any more power?

[Thorney]

so is it safe to assume bog standard n/as produce about 120 at the wheel and 145 at fly, as an average figure and with a stage 2 it just irons out the lumpy feel to give a better feel of drive but not nessesarily any more power?

Looking at the charts from Saturday - yes. However I'm not happy with that so will be making some changes.

[garyk220]

so was mine the best result of the day??? 215bhp @ wheels!

Looks like a good one CC. Torque curve looks excellent

Out of interest, did anyone RR an AMD Stage 2 VXT? What power did it make at the wheels?


PS It looks like the Wallace Performance webiste has been right all along. They've been saying for years that the standard Z20LET turbo will not make over 240bhp at the flywheel, in spite of the claims from some tuners.

Edited by garyk220, 15 May 2006 - 11:55 AM.

[mcbunny]

maybe not any more peak power but maybe more throughout the range i for one like tuners who dont promise power figures as its really really hard to make sure you get them i like tuners that know what they are doing and dont need to brag about max bhp. thorney seems to me very much like this sort of fella more concerned with overall useability rather than just all out bhp, unfortunatly people only ever seem to shop by power figures not by the quality of the product and some tuners exploit that by just claiming any old numbers to try to gain customers. i would be very happy to use thorney for looking after my vx when i get it

[christurbo]

so is it safe to assume bog standard n/as produce about 120 at the wheel and 145 at fly, as an average figure and with a stage 2 it just irons out the lumpy feel to give a better feel of drive but not nessesarily any more power?

Looking at the charts from Saturday - yes. However I'm not happy with that so will be making some changes.

And an increase of torque.

[i need nos]

thorney is a top geeza imo, id be happy to let him use my standard n/a to play with.. if u want a guinipig mate pm me and il drive up.. oh and his rolling road is brand new and its the only one id use before getting any work done and after as it will be more accurate than testing on different rollers

[cheeky_chops]

so was mine the best result of the day??? 215bhp @ wheels!

Looks like a good one CC. Torque curve looks excellent

Out of interest, did anyone RR an AMD Stage 2 VXT? What power did it make at the wheels?

yep, there was one guy i was talking to (cant remember name, another AMD/blueflame) - his was exactly the same torque/bhp curve as mine but dropped off after 5000rpm... Mine just continued climbing like a spaceship!! Cant remember what PAW he made...

[Niklas]

Ye it was mine CC I was pleased that our traces were similar up to 5000. I always thought mine seemed to tail off after 5000 and the dyno proved this. Maybe this is an attribute of the different turbo's in the 220T and the VXR,anyone? Mines AMD stage 2 + blue flame 100 Cell MS Cat From memory Peak @ wheel = 189 Peak @ crank(maybe) = 225

Edited by Niklas, 15 May 2006 - 01:00 PM.

[garyk220]

Cheers guys. That sounds about right. From memory, I think the unadjusted figure on AMD's rollers was around 190bhp at the wheels (so probably 230ish at the flywheel). This was adjusted up to 202bhp taking into account the ambient temp and atmospheric pressure... the smoke and mirrors part Torque was also very similar to CC's, but as you say, resembled a cliff face at around 5000rpm. Hence the reason the standard turbo'd cars are not making big peak bhp figures.

[nakajima]

as for the placebo thing... i've had many cars tuned and mapped, mainly turbo's and am not one to part with hard earned for nothing, it is way way smoother, its enough of a difference that my passanger noticed it straight away and he's spent lots of time in the car as stock too. had the car against a friends S2K the other night too and had a play. even the S2K driver seen the difference from his car as i was pulling away more than usual. without a doubt there is a difference, in drivability that is and thats what i'm after. if John does re do the maps all credit to him, this is part of what great customer service is about i;ve said it so many times but i'm one customer thats happy. cheers TMS

Edited by nakajima, 15 May 2006 - 02:28 PM.

[stickle]

Been looking for this thread for ages! AND NOW FOUND THERE IS TWO! Stupidly assumed it would be in the "UK Meets & Events section" where the RR day was planned, announced, discussed etc Anyway, despite all the BHP figures being lower than measured/quoted elsewhere I am quite chuffed with the ATW comparison which is what counts. Still need to get to the bottom if it is just the calculated figures that are varying or at the wheels too? VXT, Courtenay Stage 3 (inc miltek, CC etc) 196.1 bhp ATW 221 Torque ATW (over 200 from 3000rpm through to 5000) 233.6 bhp ATF 265 Torque ATF (over 250 from 3000rpm through to 4900) So Cheeky, you have about 10% more power but I have 10% more Torque! Stu

[colgy]

VXT with stage 2:

Before

Power @ flywheel: 200bhp
Torque@ flywheel: 195lbft


After

Power @ flywheel: 240bhp
Torque @flywheel: 240lbft

[M3 BFG]

Not sure if this thread relates to TMS rolling road exclusively, anyway: Before ATF 256bhp 267 lb ft After ATF 291bhp 316 lb ft Not TMS rolling road I hasten to add

Edited by M3 BFG, 08 October 2006 - 12:26 PM.