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brappage

Original Poster:

199 posts

27 months

[news] 
Sunday 30th September 2012 quote quote all
Had my car on the rollers yesterday at extreme in Whitburn, was up for a scottishvag rolling road day to watch my mates s3 and stuck the car on while I was there. Previously (before me owning it) it has ran 356 and 358 bhp at noble Motorsport. Yesterday it ran 290bhp. Was a bit disappointed to say the least. Car was run in 4th gear and the graph is nice and smooth just down on power. So where do I start looking for my 60bhp. Again the cars still in warranty. Seriously contemplating the 420 miles back to bespoke to drop it off there

daddysumo

2,478 posts

96 months

[news] 
Sunday 30th September 2012 quote quote all
Doubt you have 'lost' 60 bhp in real life... just the difference between rolling roads....(diplomacy at its best ;-) )

2.5bluenob

1,406 posts

59 months

[news] 
Sunday 30th September 2012 quote quote all
daddysumo said:
Doubt you have 'lost' 60 bhp in real life... just the difference between rolling roads....(diplomacy at its best ;-) )
You could just be opening a can of worms now steve!

TuxMan

8,128 posts

121 months

[news] 
Sunday 30th September 2012 quote quote all
It's so difficult to compare rolling road results as there are lots of things that can differ !! There is a magic "correction" factor that can make a big difference along with air intake temps and a host of other things !!! Blocked cats are common and can cause this sort of power dip , does it feel any slower ??

Tux

Gadgeroonie

5,312 posts

119 months

[news] 
Sunday 30th September 2012 quote quote all
i design rolling roads and write software for them - i am happy to take a look at the graphs for you

info@DynoDevelopments.com


what was the power at the wheels ? is that what the 290 was ?
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R0162

2,435 posts

47 months

[news] 
Sunday 30th September 2012 quote quote all
brappage said:
Had my car on the rollers yesterday at extreme in Whitburn, was up for a scottishvag rolling road day to watch my mates s3 and stuck the car on while I was there. Previously (before me owning it) it has ran 356 and 358 bhp at noble Motorsport. Yesterday it ran 290bhp. Was a bit disappointed to say the least. So where do I start looking for my 60bhp.
If the car feels the same as when you bought it then it is what it is, if you think you have suffered a big performance drop that you can feel then look for a problem.
If i told you your car was running at 230bhp would it make it any slower from when you drove it last? Was your mates S3 producing the power it was meant to?

So what was the correction for the drive train losses? Is it a 2.5? What is the boost? Any performance upgrades?
Dynos also differ by make and type, some dynos can allow the numbers to be tweaked, by very simple methods like corrections, or calculating drivetrain loss to convert from WHP to BHP. If they allowed 10% drive train losses then that made it 260 WHP for example, but it does seem a bit low even for differing makes of dyno, so maybe you are losing power from when it was mapped by NM.

Power loss is a very real thing, and can be caused by old weak actuators, faulty turbos, weak valve springs, engine wear, leaks from the manifold/gaskets, high air intake temps, fuel evaporation, blocked air filters, weak combustion, coolant temps, crap fuel, blocked injectors, faulty cats, vacuum leaks, the ECU pulling power and many other factors, for these reasons two cars that both claim to be running 420bhp from a dyno chart can be significantly different in real life performance.

Also when cars are mapped the IC's tend to be iced by either air con or charge coolers, plus cooling periods between runs, when you take your car for a power run they tend to use fans and hence your air intake temps are not as low, so this is the first thing to take into consideration and i why i like to have my car mapped using fans to simulate normal airflow and intake temps as that is the actual real life useable power you get on the road.




brappage

Original Poster:

199 posts

27 months

[news] 
Monday 1st October 2012 quote quote all
HI Guys thanks for the replies. I understand the whole rolling road lottery, inititally I wasnt going to run the car but got talked into it as everyone wanted to see it on the rollers. My mates S3 didnt run apparently it was running lean and the operator didnt want to run it, I think its more of a disagreement between tuners and he was being awkward as it has hours of data logging against it which shows its actually running slightly rich but I wont get into that.

There were about 25 cars ran on the day all which made good power, if not slightly higher than i would have expected but certainly not under. Quite a few of the cars have been rolling roaded before at different rollers and made the same power. A few R32's making what you would expect also, so all in all I think the rollers were quite accurate.

Honestly Im not sure if the car feels down on power or not. You would think you would notice if it was but it could have been like this since I got it and with jumping from my ford focus company car into the noble It always feels amazingly quick the odd time that I take it out.

I'l get the graphs scanned and send over to you mate, thanks very much for the offer of that.

The fans for the rollers are at the front of the car and its a closed cell dyno. On the 2nd run is ran 276 so a further 14bhp down on the first run which I would put down to heat soak. The car is a standard 3R and was rolling roaded by the previous owner at noblemotorsport just to check how it was running on completion of a few repairs.

brappage

Original Poster:

199 posts

27 months

[news] 
Monday 1st October 2012 quote quote all
Oh and the 290bhp was measured at the Flywheel, will check and post up the wheel figure if I have it.

andygtt

7,344 posts

147 months

[news] 
Monday 1st October 2012 quote quote all
your original dyno chart is from a set of rollers that is known to produce significantly higher numbers than others... so a lot of people are not at all surprised with the difference.

also it does sound like there are some politics going on at the RR... it is possible you got caught up in that?

Anyhow assuming this latest run is an accurate power run... as its a 3L it is actually down on power as should see 330-350bhp as std.... is it achieving 0.7bar on the boost guage when you boot it?

best get it back to bespoke as they seem to have a good reputation and with a quick road test should be able to tell if its down on power

Gadgeroonie

5,312 posts

119 months

[news] 
Monday 1st October 2012 quote quote all
Did they put a fan onto the rear intercooler ?

brappage

Original Poster:

199 posts

27 months

[news] 
Monday 1st October 2012 quote quote all
They didnt put a fan on the intercooler no. He did mention he though it was only boosting to 0.5 bar of boost. Yeah I did think that perhaps noblemotorsports rollers were being generous but this seemed alot of power to lose over standard. WIll send the graphs over and call bespoke to discuss it.

Hollowpockets

5,562 posts

99 months

[news] 
Monday 1st October 2012 quote quote all
brappage said:
They didnt put a fan on the intercooler no. He did mention he though it was only boosting to 0.5 bar of boost. Yeah I did think that perhaps noblemotorsports rollers were being generous but this seemed alot of power to lose over standard. WIll send the graphs over and call bespoke to discuss it.
Boost is down for a start then, could be a few other things but best to get it back to the guys who know what to look for.

Chapppers

4,050 posts

74 months

[news] 
Monday 1st October 2012 quote quote all
My intercooler split recently (not sure when, could have been before cadwell) so check for leaks in the system and also heat can have a massive effect if you're running the standard one.

Gadgeroonie

5,312 posts

119 months

[news] 
Monday 1st October 2012 quote quote all
There is a dyno in Bonybridge no too far away if you wanted a second opinion.

I suggest you use this as a opportunity for a set of stronger actuators and a remap

brappage

Original Poster:

199 posts

27 months

[news] 
Monday 1st October 2012 quote quote all
Spoke to Skip at bespoke and think I'm going to make the trip down to let him have a look at it and see what is required. He agrees it must definately be down on power going by the results and the boost it ran. Will let them sort all the other bits and pieces while it is in.

If im going to go the stronger actuators and map stage I would ideally be looking to have the exhaust and intercooler fitted beforehand to make the most of it. Would be as far as I would be looking to take it power wise. Ideally want a balance of speed and reliability, if thats possible!

daddysumo

2,478 posts

96 months

[news] 
Monday 1st October 2012 quote quote all
If your intake temps were too high as there was no I/C cooling fan in place then I am not suprised that the boost was low as the ECU was doing its job and letting the wastegates open at their minimum pressure, (which is prob 0.5 bar actuators) and so saving you a few quid.....

Gadgeroonie

5,312 posts

119 months

[news] 
Monday 1st October 2012 quote quote all
daddysumo said:
If your intake temps were too high as there was no I/C cooling fan in place then I am not suprised that the boost was low as the ECU was doing its job and letting the wastegates open at their minimum pressure, (which is prob 0.5 bar actuators) and so saving you a few quid.....
i don't think the stock ecu is that clever, not heard of it limiting boost before

daddysumo

2,478 posts

96 months

[news] 
Monday 1st October 2012 quote quote all
Gadgeroonie said:
daddysumo said:
If your intake temps were too high as there was no I/C cooling fan in place then I am not suprised that the boost was low as the ECU was doing its job and letting the wastegates open at their minimum pressure, (which is prob 0.5 bar actuators) and so saving you a few quid.....
i don't think the stock ecu is that clever, not heard of it limiting boost before
Ok I'm not going argue as i am not an expert, but, I've just looked at my map and from my little knowledge would say that it pulls boost after 60 degs...

YellowShed

579 posts

166 months

[news] 
Monday 1st October 2012 quote quote all
Gadgeroonie said:
i don't think the stock ecu is that clever, not heard of it limiting boost before
It certainly does it's best as it has temperature compensation for boost set point and will try and lower boost set point for air temperature and coolant temperature.

YellowShed

Gadgeroonie

5,312 posts

119 months

[news] 
Monday 1st October 2012 quote quote all
thats interesting - never had mine hold back on the boost

can it drop boost down to 0.5 bar ?

so it is totally possible there is nothing wrong with the car after all
next test is to see if it pulls 0.7 bar on the road

Edited by Gadgeroonie on Monday 1st October 22:55

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