M Roadster Dyno Results

[The Admiral]

I dynod my '98 M Roadsterin November last year at Star Performance and got 303bhp 255lbft. The car was occasionally cutting out under full throttle and the throttle linkage wasn't adjusted correctly.

Ran her again today at Dastek and got 332.6bhp 265.2lbft - well chuffed

Only mods are straight through rear pipes custom made by Powerflow.

She runs 13.6s @ 107mph 1/4s which I think is about right for the power?

[forever_driving]

Good work.

I'm thinking of starting to add some bits and bobs to mine. Although I'm not sure what to start with, I may go for the K&N induction kit and a straight through exhaust.

Does your exhaust sound any different? Personally, I'm finding the car far too quite (compared to other cars I've driven) and I like to make it a little throatier

[shadowninja]

Straight through exhaust eh? Must sound interesting

[tayloralj]

sounds like you've got a good un.
couple of questions, how many miles has its done?
i've had mine from 28k->45k over the last couple of years and if anything it feels even stronger than when i got it.
and do you have the full chart, and could you post it? i'd be interested to see how it picks up at about 2.2-2.5k rpm as thats where i seem to get a real shove in the back.
ta.
a.

[The Admiral]

forever_driving - I've got the standard air box - haven't heard if K&N do one, but if you're feeling flush, the GruppeM carbon fibre one is The Biz - apparently good for a few bhp too see www.ca-automotive.co.uk/

Basically, I asked Powerflow to remove both silencers completely and replace them with straight through pipes - it's probably too loud for most people, but I Love it They fitted an exhaust clamp so I can fit my standard pipes back on easily too - not bad for £260 with a life time guarantee? They'll custom make whatever silencer/end can combinations you want BTW...
See www.powerflow.uk.com/

My car's now done 98k and runs much better since the nice BMW Warranty peeps replaced a faulty sensor or two and ECU (see first post!) and I adjusted the throttle cable to fully open the butterflies - 303bhp -> 333bhp

shadowninja/tayloralj - I have a 32Mb video of it on the RR and some dyno graphs, but don't know how to attach them here...

Cheers

p.s. it was even better value 'cos my mate with his recently TSL tuned Impreza STi8 PPP only got 290bhp - less than before his TSL "upgrade" LOL!!

[forever_driving]

Thanks Admiral

Might look into that exhast system, especially if you can switch back to the old pipes easily.

[m-five]

The Admiral said:

I dynod my '98 M Roadsterin November last year at Star Performance and got 303bhp 255lbft. The car was occasionally cutting out under full throttle and the throttle linkage wasn't adjusted correctly. Ran her again today at Dastek and got 332.6bhp 265.2lbft - well chuffed Only mods are straight through rear pipes custom made by Powerflow. She runs 13.6s @ 107mph 1/4s which I think is about right for the power?

Being a cynic I am, I would keep a rein on your joy until you can validate the improvement as I notice you used two different rolling roads for your measurements.

Until you do another measurement on the original rolling road you will not get an real idea of the improvement.

Even then if the temperature, humidity, etc. are different then you can get a 5% difference in measurements!

Also don't compare flywheel 'guesstimates' as they depends on the 'losses' that the operator puts in - use the RWHP measurement instead and use the same 'losses' factor for all of them.

If you have the two dyno plots, do a little experiment and see if both of the 'losses' add up to the same % (i.e. if one says 250rwhp and 330fwhp then that's 80bhp or 24% losses; if the other says 260rwhp and 320fwhp then that's 60bhp or 19% losses). If the two rolling roads don't use the same figures then it shows you what a mockery the industry is! I would average the % losses and add them to rwhp to see what both claim!

I've had a variance of 40bhp between 6 rolling roads (and that's with 3 using the same equipment). I discount the highest and lowest, and then average the rest. That means my M5 has 330bhp and 290lb/ft!

One of my dyno runs was even done in 3rd gear instead of 4th, yet the result was within 5bhp of the book value. Another operator asked me what the standard figures were so that he could calibrate the rollers - büllshit!

>> Edited by m-five on Monday 5th April 10:20

[The Admiral]

Hi m-five!

I know where you're coming from - we always bitch about this dyno and that etc etc - unless we get a good result and then that is obviously the best dyno LOL!!

I especially like the guy who wanted you to calibrate his dyno for him - Ha ha!

Dastek are really impressive - they design and manufacture their own dynos and show you how it can even measure the increased drag from the alternator when you flash your lights etc - Sweet There were also several cars who ran at the Star day and got the same results at Dastek. There's no way I'm running my car again - it might get less power!

I made no friends today by "accidentally" dropping my dyno sheet in the Subaru dealership - my mate's STi8 PPP TSL put out 290bhp at Dastek - the dealer showed us a recent correspondance from Prodrive stating that "several customers have been dynoing their STi PPPs and only getting 285bhp - tell them that this is due to increased charge temperatures of over 40C on the dyno leading to an atrificial loss in performance" Bollox! - Dastek took out my mate's STi for a blast and it reached a peak 19C inlet temp, whereas running on their dyno (with frostbite inducing fans), it's inlet temp was only 17C.

Why don't Prodrive just say that their car's only have 285bhp, not 301bhp. As for TSL's 333bhp claim... Well... That's the sort of power a M Roadster has! LOL!!

Cheers

[ronnie993tt]

Nice figure Admiral. Good improvement over STAR.

I can also state for anyone, cos I`ve heard it first hand that the wee roadster sounds like a fighter jet on full throttle, with the straight through exhaust. Hell, it even scared a couple of bikers on Harleys.LOL

B.T.W who are TSL?

ronnie

>> Edited by ronnie993tt on Tuesday 6th April 01:02

[The Admiral]

Hi Ronnie!

Wo's life in England ;-) How many days 'till you get to drive the Turbo again??

Yes, I was well chuffed with the results I'm also getting about 6mpg more too - will have to drive a bit faster to get it back down again ;-)

TSL are a tuning firm who do Subaru mods - Martin got 297bhp at Star, then spent £1400 on back box, resonator and remap and then ran 299bhp - £700 per bhp and now he's only running 290bhp - trying not to laugh - ha ha ha... I think I've almost p*ssed him off enough to get a TD06 fitted to his Scoob - giving "450bhp", so that should be 285 then ;D

Is your 993tt all sorted yet? I was lucky that BMW managed to completely sort my electronic gremlins quickly and under warranty... Phew...

[The Admiral]

Here's some links to the dyno plots:

www.rog.me.uk/media/Power.jpg

www.rog.me.uk/media/Torque.jpg

>> Edited by The Admiral on Tuesday 6th April 21:59

[ronnie993tt]

Admiral

Get back in her in 3 1/2 weeks, not too long. I have to confess that I hate public transport. Much prefer the comfort of my uber-wagon. Hopefully she should be sorted for the next RR. Got some nice muffler bypass pipes from Germany to fit on her.

Mmm... £700 per bhp sounds a relative bargain..LOL. I can imagine that Martin was not too chuffed. Are Subaru going to recompensate him or sort it out.

ronnie

[The Admiral]

Yeh - would be good to se your car running at Dastek - they may even sort out your mapping for you with your new toys - or a progressive contoller for nitrous perhaps

Am trying to get Dave to run his S4 there to - it got 333bhp 390lbft at AMD and wouldn't sit on the rollers at Star - Dastek is a much more professional setup IMO

Why not join Dave Johnny and myself for our Europe trip - June 18 - 28 including Stelvio and Nurburgring