Been on the rollers.

[PB.283]

Had a run on some Dastek rollers.

Best run was 156.8bhp at the wheels and 192.6bhp at the fly.

Interestingly I had just fitted a green cotton IK and have yet to fit the CAFs. The difference between bonnet up and bonnet down was 4bhp. Not an exact test but give and indication to how much CAFs are needed.

Also you may notice my figure is quite high. And I bet a lot of people are thinking it doesn't produce that and try RS Tuning. Well I agree that there is no way a standard 182 would run 190+ at RS Tuning but does that mean RS Tuning is right?? Well according to the owner of the RR Dyno Dynamics RRs are cheap compared to dastek and one fella who ran 248bhp at RS Tuning ran 242bhp today also a standard R26 ran 218bhp and my bog standard 225 F1 ran 232 at RS Tuning. So I suppose I'm saying which one is right??

Also there was a VXR8 that ran approx 420bhp. Could not give exact as the RR was a run down one and the VXR8 was an auto and it took time to get it in neutral.

 

[BenG]

I hear what your saying, this is why people say RR's should be taken with a pinch of salt, none of them are as accurate as we would like. Its really not worth arguing over which one is better, I mean, I had mine done at RS Tuning and it ran 162.3BHP at the fly standard, its now running 179.9BHP at the fly after Maxogen, exhaust system and remap, thats what it should be running to begin with !

I think 162.3 BHP standard is a rediculous result and I dont think it is very accurate (but what do I know), I also think your result of 192.6 BHP is rediculous. Who is to know what is right and what is wrong when all we have to work with are RR figures when we all know they are not an accurate measurement anyways.

 

[PB.283]

Well where we went had an engine dyno.

Would be great to bench my engine but I'm not pay £1000s to do it.

In theory at least the dastek should be more acurate as it has a run down and not just a % added to the wheels.

Dunt mean 192 is right though. But one saving grace I ran higher than the other 182!! (by 1 bhp)

 

[daftnamewithtrophyin]

Most of the evidence seems to suggest that these units push out 165 standard, obviously. At the fly figures are fairly inexact but yours does seem high, to believe it you have to explain how two engines the same can produce such different results. What was your torque figure btw?

 

[PB.283]

164.2(lbft) at 5438rpm(bonnet up) and 158.4lbft (bonnet down) which does seem high but that was a big spike, it did not hold it for long at all.

I agree 192 seems high but a maped 225 made only 242 and that ran 248 at RS Tuning.

Bit odd me thinks.

However the thinking that the produce 160bhp only holds value cos most RRs are dyno dynamics and from what I hear are cheap RRs. The RR yesterday suggests that 182s make there power but 225s dont (one ran 218bhp) but at RS Tuning it would be the other way round, which is rather odd. But which one do you believe? The cheaper one with a simple % to fly or a more expensive one with a run down calc??

Only way to find out for sure is to dyno the engine but that is big money.

 

[j333evo]

One thing you have to remember is this, when a car manufacturer homologates an engine it is done so at a specific power and torque.

They then are allowed a 10% rule which states that all cars sold with that homolgated engine have to be within 10% of the declared outputs. Many manufacturers make good use of this rule especially with N/A engines, the larger capacity AUDI and BMW M engines are well know to use the 10% rule to the maximum capacity, so its not unheard of for a 4.2 V8 S4 to have well under the quoted 414bhp, or the 3.2 L straight 6 BMW M3's to be well under the 325bhp that they are meant to make.

It's much easier on forced induction engines to make pretty much bang on there outputs, if not more as these cars car use a torque rating so constantly open and close the waste-gate to produce a set torque figure, hence why the torque curves of modern forced induction cars very very flat.

As an example, the g/f's Dad has a Fiat 500 Abarth, this has a 1.4L 16V turbo and Fiat rate at 135bhp and 155lb ft, but on a rolling road it made 158bhp and 160lb ft which is actually more than Fiat quote for the £2K SS upgrade kit, reason being as it made its very flat torque curve it actually made more bhp as they are a direct product of each other. We then remapped it and bhp only went up to 160bhp but torque 180lb ft, on road it could really be felt. Similar results have been had on the new MINI/Pug 1.6L turbo engine with close on 200bhp made from a listed 175bhp, again torque pretty much bang on.

I should say that this was on a r/r which is run by a friend who used to work with Jon at Mahle Powertrain (formerly Cosworth Technology) where he is an engine developer many credits include the 4.2 V8 5.2 V10 Audi engines, 1.6 MINI/Pug turbo engine and Nissan's 3.6L TT GTR engine, and therefore no reason to inflate figures.

Given your wheel power of 156.8bhp I put your flywheel power at 185bhp using the tried and tested formula of FWD take wheel power add 10 and divide by 0.9.

For a full and in depth explanation of this formula read more here http://www.pumaracing.co.uk/coastdwn.htm or here is one of many online calculators that use same formula, but you need to put in whole numbers no fractions http://www.dyno-power-run.com/dynocalc.shtml

 

[Cue]

so many factors can vary the reading of a rr it's suprising, best to use them only as a guide - the same RR on the same day, run three times within 20 minutes will produces different figures!

 

[PB.283]

so many factors can vary the reading of a rr it's suprising, best to use them only as a guide - the same RR on the same day, run three times within 20 minutes will produces different figures!

Aye just a guide.

Best thing an RR does is check everything is healthy. Best for tuned cars really.

Also you can check like for like cars for most power!!!

One thing I want to check is a comparison between the standard 182 and mine cos in theory I should have a slightly higher wheel figure due to the lighter wheels. I'll have to check with the guy later as he had too spilt quickley yesterday.

 

[StevieH]

I honestly can't believe that a dastek rolling road operator stood there and slagged off a different rolling road?

C'mon, he's hardlies going to say that dyno dynamics are the best is he?

But seriously RR's are only usefull when your making a modification to your car and you want to see what effect it has had.

When I've seen other cars on dastek RR they have all made more than manufacturers figures.

And as for the run down method being more accurate, me and Chris (480bhp.com) stood and watched Scoffs renault five make 551bhp at the fly with 380bhp at the wheels? there is no way that there is a transmission loss of 170bhp. Even Scoff stood there laughing at that as he knows whats in the engine and that it's running 450bhp

As has been previously mentioned, just take them with a pinch of salt.

Steve

 

[PB.283]

He didnt slag off another RR he just said it was cheaper than his.

I was pretty impressed by the guy to be honest.

He showed us round he work shop and it was like a Mclarens head office only dirty. He was a specialist in head reworking and design and had some serious kit and heads from tons of different cars knocking about.

If i'm honest a lot of what he told us went over my head but it was good to look around.

 

[stealthsport.co.uk]

Hmmmm so your saying that all your cars had done is a filter is that right?

If that's the case I want a go on those rollers as my car's make over 200bhp easy.

Most Trophy's make roughly 165bhp standard and it takes more than just a filter including the ridiculously over priced Maxogen to give you close to the quoted 180bhp/182ps.

I've used Surrey Rolling Road and Clifford Cox Engineering and there figures were the same so I am as confident as anyone can be with these figures that my car is now making more power with the mods I have done.

However, as had rightly been said most figures are ambitious and should be taken with a very large pinch of salt but they are useful to check the air/fuel ratio and to see where the car is making power. Then you know where to rev the engine too rather than just over reving the car for the sake of it.

However if you like PBHP (Pub BHP figures) find a RR like Regal's as there's is a little off allegedly.............

:lol:

 

[PB.283]

Just want to point out I'm nit claiming to have a more powerful trophy than anyone else, nor am I claiming a a green cotton ik gives power. Just the reading on these rollers!

Why do people say it's only 160?? No-one has dynod their engine so no-one knows which rr is the most acurate. On this one clios ran well and megs diddnt. At rs tuning it's the other way round. One thing my pretty much standard car was only 10bhp short of a maped 197

 

[stealthsport.co.uk]

I'm not having a go mate but the figures are very high and I'm suggesting inaccurate.

All rolling roads differ in there figures as ambient temperature plays a big part in the readings plus if the figures are being taken when the bonnet is open with a big fan blowing into it and I believe mine were too that's hardly showing real road use.

However, if your cars healthy just go and enjoy it and don't stress about power figures

 

[maybs 69]

I'm not having a go mate but the figures are very high and I'm suggesting inaccurate.

All rolling roads differ in there figures as ambient temperature plays a big part in the readings plus if the figures are being taken when the bonnet is open with a big fan blowing into it and I believe mine were too that's hardly showing real road use.

However, if your cars healthy just go and enjoy it and don't stress about power figures

A decent RR factors in ambient tempterature, pressure and humidity so it doesnt matter what day the readings are taken it should still be the same. RR vary massivly as some require the operator to push buttons at set revs causing human error to effect the readings. Expensive RR that are fully computer operated are much more accurate giving very clsoe readings to what the car is actually producing. bonet should be shut during a run otherwise it is pointless.

 

[trophy380]

I guess it may depend as well on what fuel you were running on on the day? I was watching fifth gear the other day 'yes I know it's Mickey Mouse! especially with the clio vs tests!' but they had quite an interesting piece on higher octane fuel.
They did a test with three cars a standard Clio 3, a Golf GTI and a Subaru Impreza. They did 3 tests on each using standard fuel, and two other higher octane fuels i.e. shell optimax can't remember the other. But it showed that when running a standard car on higher octane fuel it made no difference but the golf showed about 5bhp more on the higher octane than standard fuel and the Impreza made a lot more bhp like 20 more with the higher octane so I guess what I'm saying is running a high performance car like a trophy on the higher octane fuel would make a difference and may have made a difference on the day you took your's on the RR.

 

[George K]

There have beenb lots of these fuel comparison tests, nearly always thec conclusion is that n/a cars show minimal benefit whereas turbos can show quite big gains. Als remember that JDM cars are mapped for 100 octane.

 

[nickboazracing]

Interesting reading..

I think there are a few key things to remember when testing the output of your engine.

Firstly a dyno that bolts to the hubs is significantly more consistant and accurate. Rolling road dynos suffer from tyre losses, this adds a whole extra set of variables when testing.

Secondly the atmospheric conditions are important, mainly air temp, for reasons I'm sure evryone still reading this topic will comprehend.

Thirdly is calibration. I have always been of the understanding that the calibration of a dyno can be very expensive and so many operators don't bother.

Thus it's important that if you want to more accurately gauge power and torque gains from modifications testing on the same dyno is imperative; as is ensuring you have the same fuel (as discussed), tyres and pressures (RR) and the air temp is as close as is reasonably possible to the same.

Like Matt says, enjoy the car, power is just relative. [considers opening power to weight ratio tins of worms... nah...]

 

[trophy380]

Yeah I totally agree! Theres so many factors to take into consideration. I am quite surprised that the so called 182 is actually nowhere near 182ps and feel a little let down! So is this Renault actually been very generous or is it that the engine would have been originally tested on a accurate dyno to reach those figures and that all these other readings we've all been having are actually totally inaccurate.

I mean if we compare that according to Honda the Civic type r ep3 is 200bhp, according to most of our RR results we've all been achieving around 160bhp thats 40bhp difference between the Honda which you would think would be a noticeable difference in performance as we'd all have to make considerable engine mods to gain this much more bhp. With regards to the two cars head to head the Honda's quick but the Trophy's quicker! If the 182ps figure is inaccurate then this also throws the power to weight ratio out the window probably putting the Honda in front 'can't be true!'

The same goes for the tests of the 182 vs the 197 and 200. If the 182 is only actually producing 160odd bhp then how is it as quick or quicker than a almost identical car in the 197 and 200 or is it that Renault has been very over generous with these figures too!?

I think also when it comes to 0-60 figures that maybe Renault are slightly modest as according to Renaults figures the Trophy will do 0-60 in 6.9 seconds. I've had my car head to head with my mates Civic type r EK9 (this is a 1.6 16v engine 'apparently' producing 185bhp and 0-60 in 5.7 seconds. From what I've seen in a straight line the Trophy is as quick if not quicker! and most definitely quicker in the bends! So surely either Renault are very modest and actually the Trophy is nearer to 6 seconds flat! or Honda are being very generous! I think what we can really take from this is that all these figures are thrown around but we can actually take them with a pinch of salt!

 

[Cue]

the factor in real world figures you've missed out is weight. The trophy is 200+ pounds lighter than the 197. The CTR is heavier also...

 

[trophy380]

I'm aware of the weight issue. I was just saying that if in actual fact the 182 only produces 160odd bhp and not the 180odd bhp then the power to weight ratio is a lot less bhp per ton. In which case it wouldn't have the same power to weight as a Lotus Elise as Renault suggests. Does anyone on here have a 197 that's been on the RR? would be interesting to see how much Renault exaggerated in the 197's supposed bhp as a comparison!

I love my T either way! It may have less than 180bhp but it sure as hell shows up most cars up to 200bhp +++!