Standard Dyno Run - UK Celica

[Oli]

http://www.newcelica.org/photopost/data/500/14338toyota_celica_tsport-18-02-.jpg

Not the 189Bhp it should be, but it's only done 2900miles so that could be it.

The run was done in 4th so the wheel horse power isn't really comparable.

I hope to adding some mod's over the next few weeks so i'll see how it goes.

[vvtlikick]

Power at the wheels is all that matters, not some BS "flywheel" number.

If you had a stock GT-S, 149hp to the wheels would be unusually weak. But is that figure corrected for atmospheric conditions? And how was the correction factor calculated (SAE/DIN/etc)? If not corrected, what were the atmospheric conditions at the time of the dyno run.

Also, what kind of dyno was it? Inertial? Brake? Was it mounted to the hubs, like a Dynapack?

One more question, what octane gas (RON or MON)?

[Oli]

Originally posted by vvtlikick
Power at the wheels is all that matters, not some BS "flywheel" number.

If you had a stock GT-S, 149hp to the wheels would be unusually weak. But is that figure corrected for atmospheric conditions? And how was the correction factor calculated (SAE/DIN/etc)? If not corrected, what were the atmospheric conditions at the time of the dyno run.

Also, what kind of dyno was it? Inertial? Brake? Was it mounted to the hubs, like a Dynapack?

One more question, what octane gas (RON or MON)?

Even in 4th gear? Would having 17in wheels cause the problem?

I don't know about the type of dyno to be honest. it was done on 98 RON petrol.

[Bobbeh]

Our octane levels are different to those in the US, you cant the compare figures using that.

[vvtlikick]

I've read from at least one book and a couple sites like http://www.btinternet.com/~madmole/Reference/RONMONPON.html, that RON ratings are generally around 5 points higher than the US pump octane rating. So, 98RON petrol is pretty much the same octane as the 93 pump octane gas I always use. But many Celica GT-S's run on 91 pump octane, so that'd be around 96RON.

As for different wheels, they can have an definite effect on wheel hp/torque, depending on the dyno and setup. And I'd expect the stock T-sport wheels aren't light, because Toyota isn't going to risk using weak lightweight wheels and strong lightweight wheels are pricey. Different gears/gearing can make a difference, depending on the dyno.

I think the most common chassis dyno in the US is the DynoJet, an inertial dyno that places the tires on heavy rollers and measures acceleration. It will show losses from heavy wheels/tire/flywheel/etc and variances between gears.

On the other hand, a Dynapack dyno is a brake dyno that bolts directly to the hubs in place of the wheels. So, clearly wheel losses won't be present. But it also means that there shouldn't be any inaccuracy due to differences in tire inflation, alignment, wheelspin, etc. Lightweight flywheels/brake discs/changed gears/etc. still can show losses depending on the configuration of each pull.

[Oli]

i'd say it was similar to the dynojet then.. The wheels feel really heavy when taken off so that wouldn't help.

Is 149Bhp in 4th with 17in wheels anygood? I tried 3rd but we couldn't get a reading that made sense. Lift wouldn't come on or anything?

[vvtlikick]

I've never dynoed my GT-S, but most stock GT-S dynos seem to be closer to 160hp at the wheels than 150hp. But the 17" T-sport wheels certainly could cost a few horsepower on most dynos.

When you attempted to do a dyno run in 3rd, was the acceleration outrageous? I ask because that's why lift might not have engaged, the ECU thought you were revving in neutral .... maybe :gap:

[Oli]

Originally posted by vvtlikick
I've never dynoed my GT-S, but most stock GT-S dynos seem to be closer to 160hp at the wheels than 150hp. But the 17" T-sport wheels certainly could cost a few horsepower on most dynos.

When you attempted to do a dyno run in 3rd, was the acceleration outrageous? I ask because that's why lift might not have engaged, the ECU thought you were revving in neutral (?).

If say a us celica will do 150 - 160 in 3rd. then 149whp in 4th with 17in wheels is understandable.

In 3rd yes the accleration was very fast, so i'd agree the ECU didn't active lift. I wish i could of done the test in 3rd but it just wouldn't work.

[vvtlikick]

I'll add here's some interesting SCC articles about dyno testing: http://www.sportcompactcarweb.com/editors/technobabble/0110scc_technobabble/index.html
http://www.sportcompactcarweb.com/editors/technobabble/0112scc_technobabble/index.html

[Oli]

Originally posted by vvtlikick
I'll add here's some interesting SCC articles about dyno testing: http://www.sportcompactcarweb.com/editors/technobabble/0110scc_technobabble/index.html
http://www.sportcompactcarweb.com/editors/technobabble/0112scc_technobabble/index.html

Cheers mate i'll check them out

[Oli]

That could explain the 3Bhp easily anyway.

Anyone here done a 4th gear run with 17in wheels on?

[vvtlikick]

From the nc.org dyno page:

User: X-EVIL-X
Car: 00 GT-S 6spd
Injen CAI, TRM Exhaust, 17" Rims (3rd gear) (http://www.newcelica.org/other/dyno/x-evil-x/dyno1.jpg)
Injen CAI, TRM Exhaust, 17" Rims (4th gear) (http://www.newcelica.org/other/dyno/x-evil-x/dyno2.jpg)

Unfortunately, most of the dynos don't specify gear or wheels.

[Oli]

Originally posted by vvtlikick
From the nc.org dyno page:

User: X-EVIL-X
Car: 00 GT-S 6spd
Injen CAI, TRM Exhaust, 17" Rims (3rd gear) (http://www.newcelica.org/other/dyno/x-evil-x/dyno1.jpg)
Injen CAI, TRM Exhaust, 17" Rims (4th gear) (http://www.newcelica.org/other/dyno/x-evil-x/dyno2.jpg)

Unfortunately, most of the dynos don't specify gear or wheels.

I seam to be about 10whp down then?

[vvtlikick]

We don't know how much the wheels cost you, so if we pretend they made no difference, you'd be on the low-end of GT-S dynos. But that could just be a dyno calibration issue.

To make you feel better :), here's a 151whp stock dyno: http://www.newcelica.org/other/dyno/jesse%20il/pic1.jpg

And a stock 153whp: http://www.newcelica.org/other/dyno/jasonbly/jasonbly-dyno1.jpg

[Bimbleuk]

Over here Dynojets are used on bikes, very few car Dynojets exist. Same again for Dynapack dynameters.

UK garages have mostly used water brake dynos (mostly scrapped now) or eddie current brake dynos. A wheel reading on a water brake dyno will be similar to a flywheel reading on an eddie current brake dyno. My observations after hundreds of runs on a lot of different dynos over the last few years.

The above figures do seem a little low as I would add 19% to WHP for the worst case loses to work out flywheel figures. You can't easily compare dynos because of the many variables which will affect power. Last Wednesday my car made 8 brake more than my previous best just because the atmospheric pressure was a lot higher on that day!

[vvtlikick]

^^^ I don't think it's possible to come up with an accurate flywheel power number if the engine's in the car. No matter how hard you try :)

As for the variance from atmospheric conditions, do UK dynos generally give out power numbers corrected to standard conditions? 'Cause virtually every dyno graph you see from the US will have the SAE correction formula already applied. Of course, it's just an estimate of the effect of different atmospheric conditions on power.

And some cars won't work properly with the SAE correction. From what I've read about the Dodge Neon SRT-4's boost control strategy, I'd expect the SAE correction formula will work strangely on it.

[Bimbleuk]

"^^^ I don't think it's possible to come up with an accurate flywheel power number if the engine's in the car. No matter how hard you try"

100% agree with that statement.

UK figures do seem to be mostly quoted at the flywheel using a standard correction figure. Air temp and pressure shoud be checked for every run and the 60mph figure at @@@@ RPM must be entered too.

[Oli]

i don't know if this will help anyone tell but the dyno was calibrated with the speed on the dial on the car and then the test was done. The dyno was built into the floor with a pc linked upto it and a old looking thing with a speed read out and another read out i couldn't see.

I don't think they use SAE correction just some kind of speed calibration.

[Bimbleuk]

I'm guessing there was a unit near the rollers with two analogue dials and maybe digital figures below these. Don't suppose there was "SUN" written on the equipment. Sounds like a classic SUN eddie current chassis dyno. The sort I use all the time.

The PC will either run a DOS or Windows program to plot the power graphs. I've even calibrated one of these setups before and you basically adjusting analogue pots on a crusty old circuit board. Hardly scientific!

[Bimbleuk]

Bottom line is so long as you use the same dyno for all your power runs you can measure any gains from modifications. Don't worry too much about the peak figures.

[Bimbleuk]

<plug mode on>

I've just posted a vid (vid section of course) of my car on track if anyones interested?

<plug mode off>

[Oli]

I can't remember seeing SUN on the stuff.

I had another car dyno'd there and it was around what it should of been for the mod's it had wheel and fly.

[Bimbleuk]

As you wrote previously your engine is still tight so give it a few thou more miles to loosen up.

[Bobbeh]

How did you get on at Bedford Bimble? :D

[Oli]

Originally posted by Bimbleuk
As you wrote previously your engine is still tight so give it a few thou more miles to loosen up.

I will. TRD exhaust is being fitted today.

The start of the mod's...lol

[MDK]

hmmm i dyno

[Bimbleuk]

Hi if you had 140 WHP and 208 FWHP then you had 33% loses which would make your car 4WD. Badly calibrated dyno?

[MDK]

i have a friend that has 197bhp and 140to teh wheels only its less milage then mine

dyno

http://amdlover.no.sapo.pt/power%202.JPG

[Bimbleuk]

Again your loses should be no more than 19% unless it's an auto or 4WD.

See the graph below for a good example. The power and torque line cross at approx 5252 RPM (power = torque x rpm / 5252). The car had 188 WBHP and 228 FWBHP which equates to 18% loses.

http://www.newcelica.org/photopost/data/500/14342Sports_M_228BHP-med.jpg

[Oli]

140wph is too low with mod's.

Me losing almost 40bhp through the transmision is bad but losing 68bhp is crazy.

Do the UK spec cars have bigger brakes than the US versions.

[MDK]

so what could be wrong, where m i losing power?

assuming the dyno is right!!

what could be wrong

[MDK]

could it be the cluth or the transmission is **** off

[Bimbleuk]

It may help a little to know what sort of dyno it was run on. Was it an inertial dyno like a Dynojet. The car is strapped on to a single large diameter drum. A brake dyno where the driven wheels sit between two rollers and a brake force of water or magnets is applied to the rollers. Final type is a hub mounted dynometer but they remove the wheels for this?

Looking at the graph details it is probably an eddie current chassis dyno (SUN?). Dynojets have no way to do coast down loses and therefore guesstimate the flywheel power from the wheel torque figures.

[vvtlikick]

One thing I've learned from posts on this site and specifically in this thread, Euro dynos are garbage. They give falsified and inaccurate data as a matter of course.

[Bimbleuk]

Nothing like a well reasoned argument backed up with solid evidence!

So long as you use the same measuring device each time you can compare changes which is IMO what most of us are after.

[Oli]

Originally posted by Bimbleuk
Nothing like a well reasoned argument backed up with solid evidence!

So long as you use the same measuring device each time you can compare changes which is IMO what most of us are after.


That's what i'm after. Not mine has got 2 more whp than yours!

[MDK]

brake dyno where the driven wheels sit between two rollers

its a brake dyno

[Bimbleuk]

Being a brake dyno on a std 190 Celica I would expect 150 WHP. Probably more like 160 WHP on a dynojet. With header, filter and exhaust mods you may get +10 HP flywheel but not necessarily a matching + 10 HP at the wheels.

The brake dyno just uses a correction figure to calculate the flywheel figure but they do have the advantage of working out transmission loses by measuring drag on the rollers when the car is knocked out of gear at high speed and allowed to coast to a stop.

The Dynojet can't do this hence you don't get a flywheel figure with them. However wheel power is what accelerates your car on the road not FWHP!