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hi amigo's.


like the title says, i need some advice /suggestions what could be wrong.anything what comes up in your mind.

first ,here's a video off the run, maybe you hear something, i can't.

http://video.google.com/videoplay?docid=-5709005709808797333&q=nerio02&total=4&start=0&num=10&so=0&type=search&plindex=0

so i did a dyno run on a brand new rolling road dyno, and made a sad 370hp and 480nm torque.a big disapointment for myself, i have to admit.-30hp and 20nm torque ,but the dynosheet shows a good lineair curve ,with no peaks in it all the way to the top.the tuner/and friend told me there is or has to be something wrong with the car,but cant point something out because the curve is exellent he says. just under powered.the car has 166 000 km/70-80 000 miles i guess.

so i went on a search.....i did several read outs on my gt1 and nothing comes up,not even one fault. no missfires, no AA code,no abs wheelsensor faults due to dyno, nothing. so im getting desperate.


my car had some problems with hesitations under 2500 rpm, but with the replacement of the oil seperators and inspection I, those are gone for the moment.the car occasionaly iddle's bad(scale 1 to 10 ,i would say 1 . so not often) for a sec when i put it in reverse or when it is on a ramp or something not level with the nose up. dme retakes control after a sec.no codes to be found for this problem.


for the rest it drives good, no problems ,only down on power and torque.

i replaced for now,

inspection I (airfilters,oilfilter,8 new sparky's,etc..)
oil seperators + hoses.

some things that where replaced before...

my old spark plugs lookt like almost new after max. 7000 miles.dry,no black markings of soot,so i think those where fine and no fuel problems.

mafs where replaced also max.7000 miles ago.cluster maf-test shows 137 L so thats fine to.

some coilpacks where replaced max 7000 miles ago.those are fine,no misfires.

clutch and flywheel replaced max.4000 miles ago.so no slipping clutch.

compression on the engine is all in line with the specs.

thermostat replaced 2000 miles ago. temp ok.




does anybody could have a idea what it could be?? or a suggestion what to check now??maybe exhaust cps or something???(they normally trow codes when they go south,) any idea's or thoughts are welcome.

im going to try to post the dynosheet later, i cant find the damn install cd for my scanner..:grrrr: so sorry for that/for now.

thanks in advance for your time to read this.
 

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E39 M5 Dyno Testing

...so i did a dyno run on a brand new rolling road dyno, and made a sad 370hp and 480nm torque.a big disapointment for myself, i have to admit.-30hp and 20nm torque
For a nearly stock E39 M5 with just a britalman' V2 (sic) exhaust and 166K km on the odometer, 370 RWHP and 480nm torque is really quite strong compared to what I've seen on other similarly equipped M5s on the dyno.

Losses of 30hp and 20nm torque are referenced - how were they measured? It seems that an earlier test must have been done on a different dyno. This fact in and of itself could be just the reason for the difference - two different dynos with all the attendant variables. Would it be possible to retest your car on the first dyno? Difficulties in dyno testing BMW engines are discussed in Steve Dinan's white paper "Dynamometer Testing And The Modern BMW Engine." It can be found here: http://tinyurl.com/2zbv5k

Lastly, have you seen any negative changes in your 1/4 mile ETs and mph? At this time there doesn't seem to be valid baseline horsepower and torque figures for any real world dyno comparisons unless another test on the first dyno can be obtained.

'Butt dyno' estimates are at best are just that - estimates.

Just my $0.02 :hihi:
 

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It was his first dyno run. It is a modern, state of the art dyno, which measures drivetrain loss after the run, by slowing down with the clutch pedal pressed.

The same dyno measured 'correct' HPs on other stock cars.

I'm pretty sure the 30HP is not to be searched on the dyno side, but on the M5 side.

It's also a 4WD dyno, so no DSC fuses had to be pulled, the electronics were not freaking.
 

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Something i've seen discussed on this board a while back was the fact that the actual BHP and Torque figures for the E39 M5 were less than the official figures. There have been reports of anything between 370 to 390, some stronger examples have almost 400. I think it varies from car to car.

Do a search on this board, you might find some more info.
 
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It was his first dyno run. It is a modern, state of the art dyno, which measures drivetrain loss after the run, by slowing down with the clutch pedal pressed.

The same dyno measured 'correct' HPs on other stock cars.

I'm pretty sure the 30HP is not to be searched on the dyno side, but on the M5 side.

It's also a 4WD dyno, so no DSC fuses had to be pulled, the electronics were not freaking.
I guess I don't understand how you can determine the delta of horsepower and torque losses with just one pull. Where and how is the 30 horsepower determined to have been 'lost'?
 

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Please clarify.... is that 370 rwhp or an extrapolated engine hp? If that is rwhp, you have a damn good engine. With all of my mods, I got 352 rwhp on a Mustang Dyno.
 
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I guess I don't understand how you can determine the delta of horsepower and torque losses with just one pull. Where and how is the 30 horsepower determined to have been 'lost'?
I guess the 30 bhp (370 bhp) and 20 nm (480 nm) loss are when compared to the stated output of 400 bhp and 500 nm.

I am planning to have a run on the same dyno in the very near future, and will let you know my results.
 
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I guess the 30 bhp (370 bhp) and 20 nm (480 nm) loss are when compared to the stated output of 400 bhp and 500 nm.

I am planning to have a run on the same dyno in the very near future, and will let you know my results.

Then it is apples to oranges!! 400 bhp is the Euro figure AT THE CRANK. U.S, measured slightly differently, has 394. Very few places have engine dynos, so I assume that the 370 was on a "regular' chassis dyno. 370 has to be at the wheels, which as noted above, is VERY strong.

I have 355 dyno hp with headers. Even allowing for variances in dynos, I think 370 is absolutely smoking (pun intended:hihi:).

By way of comparison, motatti, who has a faux S2, puts out around 400 at the wheels, with virtually all the S2 upgrades.

Regards,
Jerry
 

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DUDE if you nailed 370 REAR wheel hp, that is fantastic! No worries at all man, you have a very strong engine. Most of us would be very happy with those #s stock.
 

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No, no, it's not 370 RWHP ;)

As I explained in the third post, the drivetrain loss is calculated by the dyno, and the 370 HP is recalculated crank HP.
We normally work with RWHP when working with dynos and when you started talking about drive train loss, I got lost:hihi:
 

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Dyno Numbers...

...they really don't mean all that much. Dynos are great for tuning, sure, but the only other cars you can compare your numbers to are other cars that have been run on the same dyno.

I've had the opporunity to use a few different AWD dynos while tuning my Subaru here in Toronto. All three of these dyno outputs came nowhere close to each other. We're talking +/- 40hp. Even the Mustang dyno ended up not being the "Heartbreaker" I thought it was going to be... it read the highest of the three, so you just never know. (370hp/380tq for you scooby fans out there).

Tuners sometimes calibrate their dynos to show big numbers. It makes them look good. Others like to keep their numbers low, to maintain or portray a "keeping it real" reputation.

Anyways, all that said:

What kind of Dyno was it? What software are they running?

What conditions are your tires in?

What does a stock e39 M5 put out on that dyno?

I'd say your numbers are right on par at first glance. Tire slip alone could easily account for the 30hp "loss" IMO.

I've never heard of a dyno (software) that calculates drivetrain loss, that's interesting. I'd love to see the math/logic used to figure that out. I just hope its not some fixed %.
 

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nerio02,
you said you changed "some" coil packs if you haven't change them all I suggest you should, since they are a culprit for the loss of power,
also what kind of MAFS are you runing? if you have the VW ones they tend to run on the rich side hence the power loss

how are your A/F readings?
 

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Discussion Starter #15
nerio02,
you said you changed "some" coil packs if you haven't change them all I suggest you should, since they are a culprit for the loss of power,
also what kind of MAFS are you runing? if you have the VW ones they tend to run on the rich side hence the power loss

how are your A/F readings?
yes they changed coilpacks because when the mafs where shot, they gave misfires on several cilinders. so bmw changed 3 or 4 coilpacks.they thought that would be the problem at that time.after that they changed the mafs and all was well again.

im running the oem bmw mafs, i dident know about m5 board at the time :hihi:

a/f ratio they dident put a lambda probe in the back like a saw on other sort of dyno's, but i think its all integrated in the new machines gassysytem.he definitely have such a system. i have no data off that .sorry
 

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Discussion Starter #17 (Edited)
to answer some questions.

the 370 hp is crank horse power and 480 nm torque , like member frits told.

the rolling road is a brand new dyno.the brand is soft engine dynamometers.its a 4x4 synchro bench up to 1000 hp.
it has a blower on it that produces 18 000 m3/a hour. good for correct runs up to 240km/h.the bench is designed to eliminate dsc interuptions , so no fuses have to be pulled out.dubble width band lambda system integrated.


from what i understand , it works like this, you do your full rev pull and a/F ratio is mesured.then by depressing the clutch it calculates your drivetrainloss . then it recalculates all your numbers to the endresult. those are crank hp numbers then.
By this kind of test you can observe the engine horse-power and torque.
Insert a min. rpm and a max. rpm, then accelerate the vehicle up to the imposed max. rpm value, then engage the clutch: the vehicle must decelerate until the imposed min. rpm (without slowing down!)
During deceleration, the software acquires the full horse-power value lost in the transmission. In this way you obtain the engine horse-power.

you can find more info on www.soft-engine.com. there are some more explanations of what the bench can do. for those who are interested.:hihi:

yes i compared my numbers with the factory 400 bhp and 500 nm torque figures.maybe a bad thing ,but he, bmw says whe have a 400 hp/500nm torque beast ,so i take that as a refference.

tires where almost brand new ps2's(1 week old) and there was no slip on the rollers.test run with dsc on, never showed interuption from dsc.


i did two runs on that day, starting in 4th at 2000 rpm.
first run was 362 crank hp-470 nm torque/rpm 6409
sec run was 370 crank hp-480 nm torque/rpm 6400.

max torque was reached on 3650 rpm

temperature was 15,7 degrees c°
(mbar);1006
humidity;58%

and degree of correction was 0.975(asume thats correction on weather facts)



ther where several other bmw tested and they (most ) of them reached their correct cranck horspower like stated by bmw.so that means im running low in hp.
 

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Discussion Starter #18 (Edited)
These are not dynamometers they are accelerometers.

If I have to explain it, you probably wouldn't understand...

hehehe i can understand that.. i lookt it up already and its a bit to mutch for me to understand :hihi::hihi::hihi:


thanks by the way for all your reactions . keep them comming
 

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to answer some questions.


ther where several other bmw tested and they (most ) of them reached their correct cranck horspower like stated by bmw.so that means im running low in hp.
This says it all buddy. No substitute for a control group in an experiment. At least your smarter than some of the rocket scientist that post on this board.

Imperical Data Rocks!!!!!
 

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you said you test with DSC on so your problem maybe there since at times DSC engages lightly and it doesn't activate the light on the dash but it still cuts of power for a limited time, I tested thatt with my car on a numerous times and Im sure other members can assure you of that,
you should try again and swithcing DSC off, Im almost sure your results are going to be different they might even exceed your expectations ;)

:cheers:
 
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