dyno lies....

[ArthurPE]

No doubt you will provide evidence of where I have antagonised.

I suggest you carefully read the threads on this subject, for they also deal with the other points raised.

I do enjoy my car

this is not a court of law, and NO one is under any obligation to prove any thing, nor provide any evidence, just because your self-righteous indignation demands it

you are wrong
all see it
you are embarressed
get over it, move on to the next opic:

why does a 50% HP/wt difference resuklt in equal speeds?
enlighten us please

[ArthurPE]

Can you experts tell me why I have a loss (drag power) of ~35%? Is that normal? Appreciate any comments.

See attached dyno's before and after installing the MTM supercharger (stock exhaust in both cases).

that would seem high 130 w/o SC
155 with SC

I normally see ~100, give or take...
I would expect to see slightly higher losses with higher HP
so if you have 20% more HP, with the SC you should have ~20% more losses

how many miles
was the gearbox/diff oil ever changed?
after market wheels? are they heavy?
how about the clutch, oem?

have you ever timed the car before or after the SC?


my WAG? the car was slipping on the dyno

[larshs]

This was at 25.000 km, never changed the gearbox/diff oil. Have'nt timed the car properly. Changed to MTM exhaust, race cats and new sinter clutch and lightweight flywheel today (single mass). Did not feel any performance difference, but greater sound and better clutch grip. Going to do some test later today.

stock wheels and tyres, whats WAG?

Everyone telles me you can feel the difference when upgrading the exhaust, I did not feel anything, or actually it feels slower?

[ArthurPE]

This was at 25.000 km, never changed the gearbox/diff oil. Have'nt timed the car properly. Changed to MTM exhaust, race cats and new sinter clutch and lightweight flywheel today (single mass). Did not feel any performance difference, but greater sound and better clutch grip. Going to do some test later today.

stock wheels and tyres, whats WAG?

regardless, sounds like a 'beast'

I would say the stock numbers are low, the SC numbers maybe a bit low

how many lbs of boost does that kit run? iirc it's 6 psi

according to the charts you got 35 to 40%% more HP (350/250 or 510/380) that sounds high...I would expect around 20% to 25%

6 psi would yield ~40% in a 'vacuum', but after SC parasitic losses and efficiencies/heat loss ~60% of that or 25%

were the intake valves ever cleaned?
if so at what mileage, how'd they look...
if not, how'd they look when the manifold was pulled for replacement?

[larshs]

I think it's only 0.45 bar. But MTM told me that usually all B7's output ~380 bhp, but after a remap ~435 bhp. If thats the case the calculation will probably be a little different or? But with the new exhaust I expected to see 535 bhp on the dyno (Corrrected power).

Never cleaned the valves, and wasn't there when they installed the SC

[P_G]

This was at 25.000 km, never changed the gearbox/diff oil. Have'nt timed the car properly. Changed to MTM exhaust, race cats and new sinter clutch and lightweight flywheel today (single mass). Did not feel any performance difference, but greater sound and better clutch grip. Going to do some test later today.

stock wheels and tyres, whats WAG?

Everyone telles me you can feel the difference when upgrading the exhaust, I did not feel anything, or actually it feels slower?

The map perhaps needs changing to make use of the freer flowing system, usually does on non s/c cars otherwise the resultant back pressure loss makes less power and the feeling of being slower?

WAG I suspect is some sort of 'G'uess?

[larshs]

This was at 25.000 km, never changed the gearbox/diff oil. Have'nt timed the car properly. Changed to MTM exhaust, race cats and new sinter clutch and lightweight flywheel today (single mass). Did not feel any performance difference, but greater sound and better clutch grip. Going to do some test later today.

stock wheels and tyres, whats WAG?

Everyone telles me you can feel the difference when upgrading the exhaust, I did not feel anything, or actually it feels slower?

The map perhaps needs changing to make use of the freer flowing system, usually does on non s/c cars otherwise the resultant back pressure loss makes less power and the feeling of being slower?

WAG I suspect is some sort of 'G'uess?

It was remapped when installing the SC, but maybe they took into consideration I did'nt change the exhaust at that time.

Going out for a test run now - will post some numbers later

[Sims]

..
And as for not visiting threads Sims, it appears recently I can't visit any about this subject that you have not antagonised. And JR or anyone else shouldn't have to intervene.
.

No doubt you will provide evidence of where I have antagonised.

I suggest you carefully read the threads on this subject, for they also deal with the other points raised.

I do enjoy my car

Yet again selective in what you choose to respond to; at least you have consistency in that.....

ArthurPE is not correct in suggesting your first posts were about carbon intake, however only until recently has the ratio of your posts about power loss and carbonisation to general contribution been lowered by your involvement to other threads but at one stage the majority of your contribution was just that.

And as for enjoying your car, stick to that until such times as irrefutable proof exists of that which you and others believe happens.

And for ArthurPE, you struck controversy immediately in the title of this post so perhaps should not be too surprised at the response you received, Dyno Data Manipulation may well have been better.

And you did not even ask my question on which your allegation was founded. I could answer all the detail, but it served no purpose for the threads covered all the points.

Less than half my posts are related to the carbon issue, would you venture a guess at what percentage of posts by Arthur are on that subject, and of ones outside the RS4 B7 section. Everyone here can check all the posts, and come to a conclusion on the breadth of topics.

Arthur is not correct about his allegation against me as you have alluded, but yet he repeats it on the same page. That should worry.

[ArthurPE]

And you did not even ask my question on which your allegation was founded. I could answer all the detail, but it served no purpose for the threads covered all the points.

Less than half my posts are related to the carbon issue, would you venture a guess at what percentage of posts by Arthur are on that subject, and of ones outside the RS4 B7 section. Everyone here can check all the posts, and come to a conclusion on the breadth of topics.

Arthur is not correct about his allegation against me as you have alluded, but yet he repeats it on the same page. That should worry.

I am correct in my 'allegations'
but perhaps you should 'worry' a bit more about your actions than those of others...you shouldn't give a damn what others think, for several reasons: you can't influence them, it does you no good, only causes anxiety, it doesn't matter, steer your own course

what should 'worry' about is that almost 1/2 of you >700 posts in 10 weeks have been about carbon/power rating or generally antagonistic in nature...

I just went thru the 49 pages!!! of your posts...in 10 weeks, and it seems like 90% are in the RS4 forum...which is not suprising since we own RS4's...

you joined Jan 31, 2 weeks later you made the 'power claims' post
you have over around 60 posts in it alone....

as I said before, let each review your posts (if they give a darn) and draw their own conclusions...

still hanging:
50% power/wt difference, same speed...how???

[ArthurPE]

The map perhaps needs changing to make use of the freer flowing system, usually does on non s/c cars otherwise the resultant back pressure loss makes less power and the feeling of being slower?

WAG I suspect is some sort of 'G'uess?

Wild Assed Guess, lol

[ArthurPE]

I think it's only 0.45 bar. But MTM told me that usually all B7's output ~380 bhp, but after a remap ~435 bhp. If thats the case the calculation will probably be a little different or? But with the new exhaust I expected to see 535 bhp on the dyno (Corrrected power).

Never cleaned the valves, and wasn't there when they installed the SC

0.45 bar ~ 6.5 psi...

I don't buy a remap regaining 55 HP, that is 15%, huge...

I'm guessing your baseline is close to stock, 410 or so...low as I said
your SC gain: 1 + ( 0.6 x 6.5/14.7) x 425 ~ 520 HP
I would say you are about right, but remember, the dyno numbers may vary (accuracy) by 5% or more, 20 to 25 HP...or more...

I would love to see some 3rd gear pulls, timed from 3000 to 8000 rpm using the OBC timer...2000 rpm, stomp it, lol

I have to assume whom ever installed the SC would have cleaned the valves if they considered them an issue...they would definitely want to maximize power to make sure you were satisifed, especially if they cost 50HP as is claimed

[ArthurPE]

it's 15:40 on a beautiful sunny Friday afternoon...

about to leave work early (being boss has it's advantages) and jump in the yellow slug to crawl my way home...
the 5 mile trip should take less than 3 hours at the snails pace the car is capable of

maybe longer if I have to stop and open the engine up to remove the deposits which are sure to choke the life out of the engine...

[P_G]

It was remapped when installing the SC, but maybe they took into consideration I did'nt change the exhaust at that time.

Going out for a test run now - will post some numbers later

The remap I suspect would have been to alter the tables with regards to the effects of the superchasrger at OEM exhaust gas pressures. If you change that then it should be altered again because you have changed one of the parameters the original remap was based on and therefore the ECU is no fully utilising the new conditions. With freer flowing exhausts remaps alter ignition timing and fuel mixture to take account of the increased airflow in and out of the engine which the OEM tables cannot.

[ArthurPE]

here's the wt of an RS4 directly from the DOT door sticker of my car
GVWM = curb wt + max load = 5026 lbs ~ 2280 kg
max load = 1058 lbs ~ 480 kg
curb wt ~ 5026 - 1058 ~ 3968 lb ~ 1800 kg
very close to 4000 lbs <1%

the tire sticker gives the max load
the sticker below it gives the max wt (it's low, you'll need a light, black on grey)

check yours, mine may be a bit lighter, no sunroof, prem package...
I'll weigh it on certified scales very soon...

[dlextreme1977]

And yet again dlextreme1977 wades in with <beep> comparisons on Youtube but this time can't even quote the clip properly. If you look at the title graphics properly it says the M3 Coupe equiped with M-DCT has a Kelleners ECU and a Hartge exhaust which would suggest it is remapped (because I pretty sure BMW don't use Kelleners ECU's) and has an exhaust so the remap + exhaust wuld produce a power increase as with all cars.

So not really a stock car vs stock car comparison is it you Terry FCUKwit?

Frankly I'm getting a bit sick of the constant rubbish you use to try and justify your argument. And Sims, with the greatest of respect to you but you haven't been defending the indefensible, more of your posts on the RS4 being down on power or carbonisation have been in stirring up arguments whilst offering no basis of fact or evidence, merely heresay and circumstantial / unsupported data with no standardisation.

Put a sock in it the both of you unless you have something constructive to say.

And BTW, my car can vary by 48bhp dependent on which day I have put it on a rolling road and which road yet it still feels as fast and consistently hits the road timings suggested so why don't you try and explain that dlextreme 1977?

In fact you still haven't answered whether you have an RS4? I'm guessing not. Selective in your response; sure you are not in politics?

Hey no reason to be rude. Fair play, i respect you for if i had a car that cost the equivalant of £50k and it made 350-370hp when it should be making 414hp i would be pretty annoyed. Call me what you want but video proof does not lie. I think if you actuallly went to a 1/4mile day and came across an m3 or what not you would be in for a reality check. Has anybody here run a 1/4 mile and actually seen what results you get? Forget dyno's proper runs would be much more clear cut and far more meaningful than chatting rubbish and talking about calculations. Are you afraid to expose the truth or what.

There are remapped rs4's on here that struggle to break the 400hp barrier so i don't see why you claim it makes a big difference anyway. At the end of the day if you don't care i dont, if you are happy then cool- i'm not here to cause trouble but if i had an rs4 i would be looking for explanations for the under performance instead of being confrontational and critical to anybody who flags up the fact that clearly there is something not right.