john banks

Further setting up at Star today, trying the shorter 15 seconds run length with a decat MY00 and a powerful MY95. Good results with realistic looking torque curves, good boost response and well controlled temperatures. As per the other thread a decat MY00 over several tests and days is on average only 4 BHP over a standard catted MY00 at 219 BHP, which is 4 BHP (2%) behind Powerstation, 37 BHP (14%) behind PE and a whopping 44 BHP (17%) behind Well Lane.

These rollers are known to be very accurate for standard VAG motors. A lot of these have small or oddly positioned intercoolers which are difficult to cool on the dyno. Hence the use of air temperatures in the 40-50C range to give figures that try to replicate charge temperatures as they would be on the road. They are corrected to 21 C which increases Pnorm over Peng. However, for the Scoobies Jim is happy to run the air temperatures as the temperature at the airbox or cone filter rather than a post intercooler temperature so this reduces the figures a little. However, it does mean that you are not correcting every car to give it a 100% efficient intercooler.

So the results:

MY00 decat (PE downpipe, Magnex res centre, STi backbox) 221 BHP at 5850 RPM with airbox temp 33C, torque 216 lbft at 3350, wheel power 134 BHP, drag loss 79 BHP, run in 4th gear, run duration 15 seconds, charge temperature peaked at 59C for this run. Two earlier runs peaked at 51C and recorded within 1 BHP but had 221 lbft. The one shown is the third run. Boost was running 13.9 PSI peak, 13.7 PSI held and then dropping off - all standard.



So a nice baseline for a decat MY00 UK, very consistent with previous results but lower than any other decat MY00 recorded on other rollers.

Then once happy with the rollers Andy F's car went on



410 BHP (corrected) at 1.35 bar at 6690 RPM

The wheel drag curve had a fault in it towards the end - possibly to do with the paddle clutch - on an earlier run the drag smoothly increased at least 5 BHP more hence the correction to a conservative 410 BHP. My drag loss was 98.5 BHP last night with the same gearbox so it is all ballpark. This is a stunning result anyway, especially on such conservative rollers as proven by the decat MY00 which ran such low figures before. Even more impressive at 1.35 bar (with headers now) - I had to run 1.6 bar to get similar power although mine was a little richer at 11:1 at peak power vs 12.2:1 for Andy's. Who says you can't get over 400 BHP without having to use more than 1.4 bar ?

And finally a Delta Dash run of the MY00 decat in 3rd gear on the road - the boost was peaking about 1 PSI higher on the road which explains the good torque. Weight was 1430 kg (1235 base car, 30 fuel, 170 driver and passenger, -5 as no back seats )



173.7 BHP at 5465 RPM and 194 lbft at 3349 RPM. Using a conversion of *1.23 this gives us 214 BHP and 239 lbft which ties in quite well with the dyno considering the overboost plus the cooler charge temperatures on the road. Of course the drag loss is lower on the road because of a single vs double contact patch per tyre. This also supports the argument that the Delta Dash dyno is not obviously optimistic and if anything conservative compared to some rollers.

tweenierob

Bloody hell mate!!!!!!
very impressive!!

Well done Andy

Rob

[Edited by tweenierob - 5/25/2003 3:29:40 PM]

Mr J

410BHP @ only 1.35Bar !!!

And that's even with out a remap for the headers right ??

Bloody excellent result.. I must say

So your convinced that the headers Andy have work okay then John

Cheers

Jan

john banks

Yes I'll be ordering some

Mr J

Well I have a pair waiting to be fitted with the Lateral gearbox.
Then I will give the TD05 a try and see what it can do....

I know were to get the TD06/05 otherwise

Andy.F

Yes Jan this is still running the JECS, this time it has a remapped chip from Pavlo The map is by no means optimised yet as it was a 'stab in the dark' from Paul via mail !! I think it can handle quite a bit more timing yet as the knocklink was totally silent running plain Optimax Will be tampering with the mapping when I get my new ECU up n running shortly

The warm up run was 375 bhp and 301 lbft at 1.15 bar

Now looking forward to getting the misfire at high boost sorted to allow a run at 1.6 bar

Andy

Mr J

Andy will be fun to se what power and torque it will make with your new ecu

And when the misfire is gone and boost is up@ 1.6bar



Jan

5 Type R

Amazing horsepower Andy

Only 321lbft though......... Is that what you expected?

Andy.F

Yes, pretty much as expected at the lower boost level. My old TD05 made more torque at star but that was running 1.7 bar and it was just a peak.
The torque on this turbo is a flat line and does not fall off at higher rpm. It has run 357lbft at Well lane but you can't really compare the two directly.
If I get the ignition sorted I can crank the boost up a bit, add some timing and capture a few more lbft. We have a scooby day at Star next Sunday so maybe I'll have things in order by then

Andy

R19KET

John,

Unless I'm mistaken, the UK car was run in 4th, and Andy's car was run in 3rd.

It's also interesting to see that running the UK car in 3rd on the Road dyno, increased the ATW's figure by 40bhp. Even allowing for the 1psi increase in boost, that's a big jump.

It's very unreliable using "1.23" as a guide. Whilst it works in this instance, on Stars RR, it equates to 1.65, and if you apply "1.23" to Andy's figures, it only gives him 360bhp, where as "1.4" works.

Mark.

john banks

All the cars were run in 4th gear on the dyno. They all have UK gearboxes now.

The decat MY00 UK car was run in 3rd gear on Road dyno. This is because at 100+ mph they are thought to be less reliable. So the combination of a different gear with lower losses, extra boost and lower rolling losses on the road compared to the dyno could result in this being plausible?

If you use accelerometer type multipliers with RR wheel figures you would get very low readings. I presume this is due to the larger rolling losses on the rollers.

Maybe it is not valid to try and work out what you are going to get on the dyno from Road Dyno figures.

However, my previous TD05 results which I was disappointed with would have read over 10 BHP higher if the inlet temp was used as per these runs.

[Edited by john banks - 5/25/2003 4:05:24 PM]

R19KET

John,

Just re-checked the figures ! Looks like I did screw up, but the figures do seem a little odd, if the gearing is supposed to be the same.

UK car: Max power 107mph at 5850rpm = 18.29 mph 1k
Max torque 61mph at 3350rpm = 18.21 mph 1k

Andy's car: Max power 131mph at 6690rpm = 19.58 mph 1k
Max torque 107 5480 at 5480rpm = 19.42 mph 1K.

Mark.

john banks

UK car has 215/40R17 (so not standard in that respect), Andy's car has 205/50R16 (1.2% higher geared), although the difference in apparent gearing above is 6.8% so it must be tacho error. Apparently the RPM measurement does not affect the power at wheels or flywheel, but since the torque is derived, it does affect that. RPM is set on these rollers by the tachometer so there is a source of error there.

Mine was 17.7 mph/kRPM BTW. Same gearing and tyres as the decat UK car. Got to be tacho error - which would give a torque error, plus also an error of say up to 400 RPM in these examples of the RPM at which peak power occurs. Interesting not thought about that before.

[Edited by john banks - 5/25/2003 5:37:13 PM]

T-uk

I would like to say a big thanks to Jim at Star for giving up so much of his time to run cars and try different set-ups on the rollers.

it actually worked out very well that the testing was spread over two days as it meant we could go away and discuss the first session and try a few things on the second.

I have to say the results consistency surprised me, especially with the standard car. the probe proved the cooling was keeping intakes adequate, while it may be slightly pushed with a modded top mount car. the top mount cooler fan used was approx three to four feet away form the intercooler cores and the intercooler was basically continually soaked by the spray, almost a chargecooler more than an air/aircooler, a hose duct to feed the air directly from the fan to the intercooler would further improve things for the cars running more boost with top mounts.

although the results between the rollers and delta dash compare to each other nicely we did not make any adjustment to end up with these figures with either bit of equipment.

all that our wee testing sessions have done, is prove that the rollers are consistent enough.(they should be,Jim was telling us he gets them calibrated twice a year at £400 approx a time ). it has also shortened the run time to make the cars happier and improved the load timings to get graphs that look smooth and controlled.

I will be very interested in john's torque next sunday. the night we ran his car it was more checking consistency run after run,with the shorter run time than making any load timing changes.although the load resistance was never changed the timing could make a difference to the mid-range curves. if the computer brought the load in too late it would struggle to cope causing mid range over and then under shoots to try and control the system. this lead to some strange mid-range curves but with consistent figures for power up top. basically we will have to see if JB's 363lb/ft was a mid-range peak or actual true torque figure, although with things so close I think JB and andy will be mapping to death this week ,to try and better one another.

us scots will just have to accept that our cars will never give a huge figure, until we go south .

I think there are still some spaces for sunday's star day if any of the english chaps are up for it.

the double contact patch on the dyno to single on road dyno will not help loss calculations.

andy will have to comment on his box and diffs as I recall him saying it was a bit of everything to get the car running. could tyre wear and pressure also not play a part?

john banks

No chance to run the wideband before next weekend, so I'll probably run similar again.

Andy.F

The reason for the difference in MPH / RPM is mainly due to the tyre size difference, John's being worn out on the front and my higher profile set being fairly new. This can give a difference of 3%. The tacho accounting for any remaining difference, it was noticable that my car was on the rev limiter at the end of each run. This is set at (a puny) 7000rpm on the chip Paul sent me, the dyno was showing 6690 max.

As JB said this only alters the torque calculation although I can't quite work out whether I should have had more or less ?

hypoluxa

Andy - fab result for such little boost, but the dyno plot looks flawed, as crossover point is circa 6800rpm...?

John - it was my old UK MY00 that recorded 214bhp and 214lbft at Powerstation. Exhaust was a closed neck 2.5inch Scorpion system(crap b/b btw). The interesting part (apart from the low PAW figure) is the ambient temp of 15c and the correction of only 0.5bhp. I've scanned the graph so you can compare it with the Star MY00.



I wonder how many peeps will agree with you by reducing their Well Lane power figures by 17% hmmm...

R19KET

John/Andy,

"Apparently the RPM measurement does not affect the power at wheels or flywheel, but since the torque is derived, it does affect that. RPM is set on these rollers by the tachometer so there is a source of error there."

Both the UK, and Andy's car's power/torque graphs appear to cross at 5252rpm, which is correct.

Since torque, and bhp are directly linked, if the graph cross's at 5252rpm, either both the figures are correct, or they are both wrong. I'm not suggesting either, just trying to understand the anomolies.

I know that PE calibrate each car at 60mph, but as we know, this can easily be up to 10% out, too.

Mark.

Andy.F

Hypo' Check the scales on the 2nd graph Torque is on one side Power on the other.

Mark

I'm not sure how the torque is derived in the software but the rollers plot power at wheels. The engine rpm is not required in order to get a power output. However in order to give a torque figure, the RPM must be known. If you key in the wrong RPM then the engine speed measure along the bottom of the graph will move a bit, now assuming that the software calculates torque by the standard calculation then the torque curve (or flat line ) will move with the RPM scale, hence always crossing at 5250 regardless.

Does that make sense ?

Andy

hypoluxa

Aah... yes. My mistake

I was under the impression that it is torque at the wheels that is measured, or rather torque at the rollers. Bhp at the rollers is then calculated from torque x rpm(of the rollers)/5252.

If engine rpm is measured alongside roller rpm, then you can calculate hp at a particular engine rpm.

Andy.F

Yes, you are correct. A torque read out from the rollers would be meaningless however without entering the gearing details of the car.

The torque at the rollers*roller rpm/5252 will give the power developed at the wheels. This is what is plotted on screen during run up. The point I was making was that even if the engine RPM is unknown then the power plot still stands unchanged.

Only once a reference RPM is added can the engine torque be calculated. It is just a calculation from the original PAW + rundown losses but using engine RPM in the equation
eg Pnorm/engRPM*5252 therefore the crossover is always going to be at 5252 regardless of rpm entry error.

Andy

pat

Andy,

I think that congratulations are in order, over 400 BHP from such low boost is quite an achievement!

Do you now see my point about the limitations of the standard headers ? Like I said before in another thread, it IS possible to force the gasses through for even higher power, but perhaps you'll agree that my concerns about the cost, in terms of EGBP, were well founded ?

Perhaps you'll also agree that since your power peak is occurring pretty much at the top of the rev range, your heads do indeed flow somewhat differently to the "norm" and that they are an important factor in releasing those horses

Cheers,

Pat.

john banks

I've got to catch him up with headers and STi heads Pat and a few more ccs to make up for the lower weight

Andy.F

Cheers Pat

I never doubted that an improvement in VE would be achieved with tubular headers, I just didn't expect quite as much difference !!

I still don't think the heads are any different from a Ph1 WRX though ! Without checking them on a flow bench it's difficult to tell. Before I fitted the headers, JB's Ph2 UK car was making the same power as my one but with even more torque.

I'm sure the reason the power is at such a high rpm is due to the boost profile I was using and the free breathing turbo, there is no choking of the exhaust required to get the boost pressure.
When I was running the TD05 the power peaked at around 6000 rpm which is a fair bit lower than most others.

When I can increase the midrange boost the power curve should take on a more familiar shape.

Andy

AlanG

I don't see it crossing on Andy's graph.

john banks

Values do, curves don't (different scale). Well at least the P-eng and the torque would cross, Pnorm is plotted so doesn't and will be a little out.

The torque is calculated from Peng*5252/RPM, so values in BHP and lbft being equal at that level proves nothing except that the software uses one to derive the other. Any difference on these rollers will be due to atmo and temp comp.

R19KET

I wish all RR's would use the same scaling for power, and torque, it's so much easier to see what's happening.

They've managed it forthe UK car, why not the others ?

Mark.

[Edited by R19KET - 5/27/2003 9:19:49 AM]

john banks

I think when they run a lot more power than torque the software automatically rescales, but I prefer one axis also as it is clearer.

Andy.F

Just read it all from the left axis then WOW I've got 415lbft at 1.3 bar (no sniggering Mark !)

R19KET

Andy,

Moi ! Actually, I checked it, but it seems to give you about 320bhp

400bhp + from 1.35bar is fantastic. I know you use methanol, but what type of mix are you using, and what other "additives" are using in the fuel ? I believe you have an alternative to NF.

Mark.