teknopete

Did some 1 say Tekno

Oh no sorry it was John mentioning techno babble

Right my heid is now officially bursting with this, I just checked my last 3 results and found what?? Most recent 1st :

Npower 304 @ 6830, 237 @ 5890, 246 @ 5980
Torque 256 @ 5780, 240 @ 4510, 251 @ 4350
Wheel 173 , 173.5 , 175.5
Drag 103.5 !!! , 59.5 , 60.0

BOOM!!!! goes my head....

So what`s it all about ??? now
Virtually no @ wheel change, virtually no torque change (duh)
Data overload Can any1 make sense of it??
Especially the drag figure hike.

L8r
Pete

Dave Brown

Sam....nice thread you've started..think we need a rolling road forum in our scottish forum
Dr Banks...I wouldnt go back to a td04 ever, The vf really is a good route to take.The small amount of lag, gives yer time for the big cheesy grin to appear just before you blast off .Youre welcome to a shot of my car if you need more convincing.

So peebs..what else could we do to accurately measure our cars performance?? Remove our engines and have them bench tested...i think not.I agree that its down to the consistancy of the operator, but we all know our figures are just a guide, at the end of the day.But its still the easiest & quickest way to guage what modifiactions/upgrades give the best gains and thats what interests me most from a tuners point of view.

Jim mentioned that he is getting a better & more efficient TMIC fan, a 'snail' style one.Hopefully he will have it installed for our next RR meet and we can see if it makes any difference to our figures.BTW my last power run was done the same as usual, Jim only inputted the cars weight for doing the 0-60, 50-70 runs, sorry if I confused anyone.I'm hoping to get down to Star tomorrow for another run to compare figures with my swap from Vf28 to 23...I'll post the results for those interested.

Dave

evojkp

Maha/Jim ??

Good to see you entering the lions den. Yeh must get a laugh at us professionals?

Just ignore me am a bit pi%%'d after watching the fitba'

keith cowie

hi john i thought my post would get jim to
come on here for his first post

good on ya jim

keith

T-uk

Pete,

funny that the Pnorm goes up with the higher revs but the PAW wheels stays consistent.just out of interest at what revs do the wheels peak although the fmic may have thrown this out.

by the way,what type of front mount is it you have and did you need to change the radiator at the same time for fitting reasons.just been thinking that I could get a front mount for this car and fit it to a STI7 in the future.

The_Gza

Lo all

Been trying to decipher this thread, but it just ends up like that episode of The Simpsons - blah blah blah blah, blah, blah, power at wheels, blah blah, blah torque, blah, blah

All sounds very serious though and quite interesting once I have completed my "mechanical knowledge" degree. I'll let y'all know when I have a clue wot you are on about

Cheers,


Chris
PS Does any of this explain why my car had such a crappy result last time around
PPS Looking forward to Crail at the end of this month - we can maybe see who is all mouth and no trousers then Never mind RR figures - get out there and give it some wellie
PPPS John - you ain't the only one indulging after the fitba!

Scoty

Good result guy's,

and I'm no talking about rolling roads

Scoty

evojkp

Gza, I'd thought of a REALLY GOOD reply, but ah forgot what is wis by the time I'd hit reply to thread.

Is it nae a bummer whin that happens.

Also noticed thit whin am gassed ah stert typin like a choooooghtir'

Strange....by the way, hae ye seen Halle Berry in Swordfish

The_Gza

Funny you should say that - got a loan of it yesterday

Nice but not worth the half million quid she got paid for showing her puppies

Sam Elassar

hi jim it is good to see you on this board i thought we are going to manage lure you in somehow ,

couple of things i don't understand and i will appreciate if you can explain them to me. i am not talking about rolling road days designed for the masses here

can you input the car weight to get a more accurate transmission losses, assuming that mine for example should not have been that high 120bhp!!!!! can the load on the rollers be altered or is it done automatically?

another thing, i have noticed the inlet temp reading that other rollers have seen, as kieth mentioned. as there is also alot of evos on that dyno. and they must have the inlet temp sensor in a different position as they are getting around 17-20 degrees. which i don't think is right. i think the temps are around 65-70 for a scoob, and maybe around 45 for FMIC cars. but is there another position for it?

you also mentioned that if charge temps go down the torque and boost will go down and therefore the 5252 cross over is not achieved. but i don't understand that, if the torque goes down surely the power will go down as well won't it so they should still cross over at the same limit but shallower curve.


it is just transimission loses seem to be all over the place see pete's car for instance? i could not explain why it had such low transimission loses in the first couple of runs but and i was even more puzzeled so see things go the opposite way.
the only way i can see is that because the fmic on pete car allowed the car to be reved all the way to 6800rpm thus achieveing more speed on the rollers and increasing the transimission loses?


which takes us back to rev it to increase your fly wheel figures? it should not be the case if the load is correct ir am i way off as usual


thanks in advance

john bank
now you have an offer from DB that you can't refuse


sam

keith cowie

hi sam the 17 to 20 degrees that you are talking about is the
air temp out side the engine bay
not the engine intake temp.

when does the weather in fife ever get that hot 50 degrees plus.
at tuning japanese they had the temp sensor at the air filter
reading the temp of the air going into the engine.

the temp after the intercooler is another thing all together.
if the charge temp is going to high you need a bigger intercooler or more cold air to keep everything cool
the hks intercooler on my skyline runs on the road runs about 2 degrees above ambient.
on the road i can see a max of maybe 30 degrees 8k in 3rd gear
on the dyno it will show 45 degrees after only one run

anyone please feel free to tell me if i am wrong

thanks keith


[Edited by keith cowie - 2/6/2002 1:24:41 AM]

[Edited by keith cowie - 2/6/2002 1:28:44 AM]

john banks

Dave it sounds like you have a cupboard full of VF series turbos

Dave, I would love a shot thanks for the offer although it will probably be the slippery slope through FMIC and Link

Cosie Convert

guys

You can't change the laws o physics ! See my post in technical for more detail.

Due to lack of TMIC cooling on a rolling road, a FMIC on a 300 bhp car will show you a false gain on a rollers of approx 30 bhp. The real gain on the road at this level of bhp will be closer to 10 bhp.

Pete - What did your performance meter tell you the difference was on the road after fitting your FMIC ? bet it wasn't as much as the rollers did

1% power per 10 deg F. Work it out for yourself

cc

Dave Brown

Hi Guys

Another interesting afternoon on the rollers.
We were investigating Sams rpm/torque/bhp crossover points.Looking at last weeks graph, run in the usual manner the crossover point was 5,400rpm.Today Jim hooked up the rpm probe to my plug lead, instead of the usual 2,000rpm set-up.He did a power run, then printed off the graph, the crossover was at 5,100rpm (give or take 100).

So whats the benefit of a VF23 over a VF28 running both turbos at max efficiency with a TMIC??

heres the results to compare-

vf28
287.0 bhp (max @ 6,040rpm)
200.5 bhp (wheels)
280 lb/ft (torque max @ 3,800rpm)

vf23
297.5 bhp (max @ 5,490rpm)
210.5 bhp (wheels)
314 lb/ft (torque max @ 4,280rpm)

Very pleased with the results and big thanks to Jim.

Dave

Cosie Convert

Excellent result Dave What boost were you running ? Was that with the new top mount cooling fan or the original fan ?

cc

Dave Brown

CC

Cheers m8.

I ran 1.35 on the vf28 & 1.45 on the vf23.

Just need to see how much my 1/4 mile times have improved now.

Dave

slimshady

pete,

me thinks dave-b is going to kick your *** at crail this year !!(as usual)lol . get your excuses ready big man !!!


slim

maha

Hi sam. Sam we ran a standard evo7 with the diff set to gravel, it produced 278bhp at flywheel. When we ran your car both times it was set to snow how about coming over 1 afternoon for a couple of run FOC just to see if this is causing a high transmission loss.
P.S t-uk the last run you had produced good power at the wheels but a dragging clutch was the cause of your high trans-loss, which is then added to power at wheels giving a high flywheel power. I did say at the time.

T-uk

jim,

the PAW has never changed from one run to the next that you have given me.the last time though the car had just got a new clutch under warranty for judder.

I do not actually remember talking to you after the run,as I went straight out and parked the car up,you thought I had left and only printed up 1 sheet for Pete but gave me a photo copy.

I have dug out my old results and see that at the first day I got:
218.5 p-norm -(5850rpm)
210 p-eng
139 p-wheel-(roughly 5800rpm)
71.5 drag
230 lbf-torque.

at the next day I got:
234.5-n-(6440rpm)
220-e
139-PAW-(roughly 5800rpm)
81.5-drag (had not noticed it was higher)
227-t

bloody consistent if you ask me ,which is why I am against you changing your loading technique.

at the very last scooby r/r day I was up with a m8's Xreg with Dawes@1.1Bar.we lost his print so hopefully Pete will get the graphs up soon,but off the top of my head the figures were:
241-norm (6500ish rpm-max revs about 6600)
136-PAW (5900ish rpm)
244-torque

do you not think,that revving the car higher gives you bigger flywheel figures for the pub and which do you think is more accurate for comparing,same car and same geared cars together,norm or PAW's?.I do not think that we can compare PAW of say Sam's Evo to a scoob,but would have thought Evo7 to Evo7 PAW to be more accurate and UK scoob to UK scoob,PAW to be more accurate than flywheel.

cheers john

Cosie Convert

T uk

My 2p, FWIW

As the Engine power approaches it's peak, the rate that the power is increasing at the flywheel is less than the rate that the drag is increasing on the rollers. So the PAW 'appears' to be falling as the engine approaches peak output.

As Sam has stated, this is due to the abnormally high drive losses caused mainly by the 2 contact patches per tyre. Out on the road, your PAW would still be increasing proportional to flywheel power.

I think you and JB are correct in your approach. In order to measure your peak flywheel power, you need to drive through that drag increase and let the dyno work it out by adding in the drag figure at the end.

Some have suggested that this has inflated your results, I would suggest it is the others who have lost out

Most of this has been covered already but I think some still don't understand your logic.

cc

Sam Elassar

hi jim
both of my runs were actually done in gravel and not in snow. but since you have offered FOC how can i refuse

i will phone you tomorrow to arrange a date and then i will post the results.

CC
that is just another way of looking at it what i was aiming at is we should take all the cars to the same limit. don't you think?

sam

Cosie Convert

Problem is Sam, the cars all have different power bands and rpm limits UK v JAP v Evo.

With bikes, we run them all to the limiter however even that is not consistant as some have the limiter setting raised !
I'm not sure that everyone would want their car to run to the limiter

If you fix the rpm limit, then that would suit some cars and not others. A UK will be there all day trying to achieve the 7500rpm you suggested : :

I think it's best left to the individual to request shutdown at peak PAW or hold it longer for peak flywheel.
Depends which number you want to know

cc

maha

Sorry t-uk it was teknopete that had high losses.
Sam some thing to think about, I have just finished a rechip & cats with exhaust the car is an Audi RS4. It made 440bhp at flywheel & 441lbft the wheel losses are 88bhp the car was taken to 7000rpm. P.S it 4 wheel drive. Me think the germans got some thing right.

Sam Elassar

WOW!! that is some serious power for just a chip and exhaust

german cars are good but they are heavy to start with and usualy driven by old people (not talking golfs here). maybe when i am older with a family and a dog in the back i will get one of these wagons

sam

EvilBevel

Oi, why are you guys hiding a perfectly good thread in the Scottish forum ?

>>I suppose it might be tricky to reach all speeds in all gears on the road though "Sorry officer just mapping 6000 RPM in top gear."

Mark works about 4 miles from a non speedlimit restricted German autobahn. Although I have to say it was ***kin scary to sit there with the laptop at 260 km/h (counter) with Mark driving & looking at the Lamdbdalink, boost gauge & revcounter instead of the road

The more I read about RR's the more I get confused to be honest. I feel we really should try to make an extensive FAQ about it, starting off with the facts that are non-disputed (unlike the facts that are disputed <-- stupid me)

Best "power" test I ever witnessed was a combined 0-100 km/h, 400 meters, and 100-200 km/h test with the same driver & co-driver (measuring) each time. It doesn't give you power figures, but it's a good test to see how quick your car really is.

As for the PE vs other RR's: I'm planning to do a UK trip this year and do a run at PS in the morning and PE in the afternoon.

Theo

Sam Elassar

hi THEO
can you imagine how many replies and opnions we would have got if this was in drive train believe me it would have got even more confusing!!!

your tuner obviously know what he is doing as air in the rollers ( inside a garage) will be alot less dense than on the road and therefor the map can be richer than it should be on the road ( safer though). unless of course the RR has got a fan that can blow 260km/h air . also it is very difficult to direct air into that scoob on the rollers.!! can be tricky. what does your tuner do? bonnet up/down what speed of fan, where is positioned? does he measure the inlet temps? where does he position the probe?

so theoritcally if the fan can give you 80mph worth of air that all you should do on the rollers. ( unless there is something else that i am missing) of course if the car is MAF based then that does not really matter if the targets are set correctly.


sam

Sam Elassar

will email you richie when i get a date arranged. i would not mind doing a 0-60 time as well i will probably need to pay for that though

Richie1

cool

harvey

iTrader: (48)

Hi Sam : Been following your thread with interest. The formula BHP=T x RPM/5252 seems to have no relationship to my last 3no. runs at Well Lane 1) 274 BHP @6349 RPM 272 ft/lbs@4000 RPM. 2) 309 BHP @6127 RPM 269 ft/lbs flat from 4250 to 5500 3) 316 BHP 6157 RPM 281ft/lbs @3900 RPM The cross over points do approximate to 5250 RPM. For run 3) for instance BHP=281 x 3900/5252 =208.66 BHP Run 1)= 207 BHP. Are these P.A.W. figures? or am I missing something? Any other comments greatly received. (STi Wagon Ver 6)

harvey

iTrader: (48)

Hi Sam : Been following your thread with interest. The formula BHP=T x RPM/5252 seems to have no relationship to my last 3no. runs at Well Lane 1) 274 BHP @6349 RPM 272 ft/lbs@4000 RPM. 2) 309 BHP @6127 RPM 269 ft/lbs flat from 4250 to 5500 3) 316 BHP 6157 RPM 281ft/lbs @3900 RPM The cross over points do approximate to 5250 RPM. For run 3) for instance BHP=281 x 3900/5252 =208.66 BHP Run 1)= 207 BHP. Are these P.A.W. figures? or am I missing something? Any other comments greatly received. (STi Wagon Ver 6)