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Discussion Starter #1
First of all...new member here...from Spain so...sorry for my English level¡¡


I´ve been reading this board for a while...I always loved the E39 M5 but here in my country It´s not easy to find a good unit...

Last year I had the chance to buy a good one (06/2000) right now with 125.000 miles on the clock.






I love the car...but...

Last week I dynoed it:



Another M5 did 390HP..so there is something wrong in my car..

The dyno guy told me to check the MAF sensors...I tested them (138l/h)

O2 Sensors...Ok, I must change them but...35HP less?

Vanos...

I did a Vanos test using DIS v.57:





So..

1) Bank 1 Vanos is the guilty guy?
2) Intake CPS were changed for a new ones last week before the Dyno test


In your opinion....what is the first step?


Thanks¡¡

PD. I´ve read every single thread about vanos test on this board, but my only concern is the lack of power...
 

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I doubt that vanos is your problem, I agree it is not correct but... The problem is the test stops when it finds something out of tolerance. The cam retarded too much and likely won't advance as far as it should. Possible that the vanos is at its max advance during WOT, could be the cause but there are a lot of other things that steal power. If there is power lost.
The other car made 390 at the flywheel or the wheels? They make that at the flywheel not the wheels. I don't read spanish so I have a hard time making heads or tails from your sheet. Most dyno stuff I have read report power at the wheels, allowing for drivetrain loses you seem about right. Truly I can help with the vano not dyno reading so wait for someone else's answer on the power. You could try reading the dyno threads.

For the vanos with the CPS being new, that only leaves mechanical timing as what could be at fault.
 

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Discussion Starter #3
Thanks Sailor.

You are right ...390 at the flywheel is the value that the other M5 reached.
Here we use a kind of Dyno called MAHA that estimates using an ISO regulation the power at the flywheel.

So..

231ps at the wheels is the value that you shuld use to compare with your RWHP.

Air filters/Spark plugs/Fuel filter and all the oils have been changed last month.
 

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Measuring flywheel hp from the wheels is a whole different issue, but if the wheel power number is correct there is something seriously wrong with that car, 231 ps is 228 hp. That's not a few degrees of cam timing error, that's several cylinders not present.

I am going to guess that there was an issue with the dyno.
 

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Discussion Starter #5
Measuring flywheel hp from the wheels is a whole different issue, but if the wheel power number is correct there is something seriously wrong with that car, 231 ps is 228 hp. That's not a few degrees of cam timing error, that's several cylinders not present.

I am going to guess that there was an issue with the dyno.
It's the way the MAHA measures the power.

Can't explain the reason but if you dyno your car in a MAHA you will obtain these numbers.

Here you can see a couple of dyno graphs from my ex euro M3 e36 EVO and my ex 330i e46.



 

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Pull the scene shots of your fuel trims. Also your ICV adaptions. Maf readings at idle. I would also be interested to see the cam sensors at idle, 2500 rpm and WOT. You will need a helper for that. Screencaps are way better than pictures. Hit PrtScn and then open an image edit tool IE IrFan View (freeware) and hit paste then save.

BTW you are only a few degrees out on your vanos. It should not amount to that much power lose as the DME will still be able to put it where it wants except max advance.
True we don't know what the exhaust is doing on bank 1.
 

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Discussion Starter #7
Pull the scene shots of your fuel trims. Also your ICV adaptions. Maf readings at idle. I would also be interested to see the cam sensors at idle, 2500 rpm and WOT. You will need a helper for that. Screencaps are way better than pictures. Hit PrtScn and then open an image edit tool IE IrFan View (freeware) and hit paste then save.

BTW you are only a few degrees out on your vanos. It should not amount to that much power lose as the DME will still be able to put it where it wants except max advance.
True we don't know what the exhaust is doing on bank 1.
Tomorrow morning I´ll post them.

Thank you very much¡¡
 

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Discussion Starter #8 (Edited)
@rao

I´ve been doing a little bit of research in order to clarify how to look at the dyno graphs:

Potencia motor: Is the ammount power obtained in the test with the ambiental conditions described on the right, we obtain this value if we equal
(Pot. ruedas + Pot arrastre)

Potencia normal: Is the ammount of power that you would obtain in a ceretain ambiental conditions, in this case as you can see using the DIN 70020 regulation that estimates the power with 1 Atm of pressure anf 17ºC, they do that because at the sea level our engines obtain a different value of power.

Potencia a las ruedas: RWHP, they deduct all the transmission loses.
Potencia de arrastre: Is the ammount of power that is used to move the Dyno.


So, in this case, my car has in a perfect world 354ps, the other M5 did 390ps.
Best unit on that dyno did 392ps
 

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Dam we must be cut from the same cloth, I have been researching too. Can you get the print out of the 390 M5?
(Google is not so great but it really looks like that dyno was,,,,) I would not say poorly set, I would say not set. Just from the numbers you posted. Shoot us the other numbers from the other car. Then are they run by the same dyno?
 

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Discussion Starter #10 (Edited)
Dam we must be cut from the same cloth, I have been researching too. Can you get the print out of the 390 M5?
(Google is not so great but it really looks like that dyno was,,,,) I would not say poorly set, I would say not set. Just from the numbers you posted. Shoot us the other numbers from the other car. Then are they run by the same dyno?
I´ll ask them for the dyno graph. Hope to get it

The 330i E46 was measured in the same dyno, but in a different location, they moved to a bigger place this winter.

The M3 e36 EVO was Dynoed in a different shop, the guy who owns that place has been working with //M cars his whole life.

We "should" trust that Dyno because he develops maps for rally cars.

The reason why I am not usin his dyno is that he is always very busy and he lives very far away from my home (300miles).

For example here you can see an M3 e46 dynoed in a different MAHA dyno in Madrid:



As you can see the RWHP are always very low compared to your normal values.

PD: Comparing with the other cars there is something curious..I´m losing 20/25 PS in my transmission... 105ps vs /85 ps
 

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Discussion Starter #12 (Edited)
@Sailor24
Must apologize for the pictures but I did also a few print sreens, VMWARE doesn´t allow me to take them...I´ll fix it ASAP..


INPA Screens:




Idle


2500rpm´s



Did a couple of screens at 7.000rpm...don´t know if it´s what you needed, I was reving the car and my girlfriend doing the captures...






And now the DIS pictures:



































PD.

I´ve just beginned using INPA and DIS so maybe there is sth. wrong...

Thank you anyway for your interest.
 

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As rao says, your rear wheel HP (potentia ruedas, the power directly measured by the dyno so the most honest number) is way down on the ~320 HP a healthy M5 would show.

So either the dyno was badly out of calibration, or you have a major problem with your engine.

Since your INPA and DIS data look good, I don't think it's likely you have a problem with the engine. A compression test would confirm this as I suppose it is possible the compression on all cylinders could be very low, which may not show up obviously on INPA or DIS.

You could also do the full-load MAF test using the secret menu. If you get 125-140 l/hr fuel consumption, that would also indicate there was nothing wrong with the engine.

By the way, potentia arrastre is the power consumed accelerating the drivetrain between the flywheel and the wheels, not the power consumed by the dyno. This would normally be around 70 HP for the M5, so the 105HP calculated/assumed by the dyno is too high.

Malcolm
 

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Discussion Starter #14 (Edited)
Thanks <!-- BEGIN TEMPLATE: dbtech_usertag_mention --> @68FB <!-- END TEMPLATE: dbtech_usertag_mention -->

I´ll check everything..I´ve posted all the dyno graphs just to show you that all of them offer similar WHP...that makes me think that there´s something we don´t know about the way the MAHA measures the power.
I´ve also tried to figure out how the Dynojet works...

Refering to he compression test...I want to notice sth. I have no oil comsumption...I´ve done 3.000 miles and the oil is still at the maximum level...anyway I´ll perform a compression test.
 

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My bad when I asked for the cam position I should have told you pedal position. Those were from holding that rpm not foot to the floor?

Your exhaust valves on bank one are as far as the intake on the same bank. As you can see the vanos still holds the value it is looking for. At least it is equal to bank two. That pretty much rules out vanos fail causing this huge power loose.
From the computer there does not seem to be anything wrong. It has to be the dyno.
 

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Discussion Starter #16 (Edited)
My bad when I asked for the cam position I should have told you pedal position. Those were from holding that rpm not foot to the floor?

Your exhaust valves on bank one are as far as the intake on the same bank. As you can see the vanos still holds the value it is looking for. At least it is equal to bank two. That pretty much rules out vanos fail causing this huge power loose.
From the computer there does not seem to be anything wrong. It has to be the dyno.
If I understood correctly your last message , you´re right I did it WRONG...both WOT printscreens were taken holding the RPM´S

I also did a couple of WOT tests measuring MAFS, I had a peak of 137L/H.

That´s why I opened this thread, Dyno values obtained in different places using that Dyno show similar WHP values

Everything in my car seems to be ok. no oil consumption, normal vanos sound, normal fuel consumption...It´s well maintained

But I´ve a lack of power....

The only test that fails is that BANK1 vanos test....
 

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Discussion Starter #17 (Edited)
Ok, here I ´ve got a couple of numbers to compare...

2 M5 e39 both of them Stock and in mint condition.

MAHA DYNO

297WHP
302WHP

Both of them used between 101/110 Ps to move the dyno

(different ambiental conditions)

You say that 320/330WHP should be a normal value.


It looks obvious that I´ve lost a lot of horses....maybe 50/55WHP but If I´m going to use a MAHA 320/330WHP is a number that I won´t obtain here in Europe
 

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I also did a couple of WOT tests measuring MAFS, I had a peak of 137L/H.
This test isn't just a fuel consumption test. It's an indication of how much power the engine is making, although in a rather indirect way.

The DME uses a maximum power AFR at around 11.9:1. So using 137 l/hr of fuel means your engine is sucking in around 1200 kg/hr of air. That's what a healthy M5 engine making around 400 HP flows. I suppose the engine could use 137 l/hr of fuel and suck in a lot less air for some reason but that should be obvious, e.g. black smoke under full power, fuel trims way off, terrible fuel consumption.

I just don't see any indication there is anything wrong with your engine. Why do you think it is down on power?

There are some other tests you could try. Do you have access to one of the accelerometer-type performance meters like Tesla Gtechpro?

And there are roll-on tests like this although they are not very accurate:
http://www.m5board.com/vbulletin/e39-m5-e52-z8-discussion/121622-80-120-kph-4-8-sec-4th-gear.html

Check out this thread on doing a compression test as I found it a bit tricky:
http://www.m5board.com/vbulletin/e39-m5-e52-z8-discussion/69610-tech-how-accurately-compression-test-s62-engine.html
 

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Discussion Starter #19 (Edited)
This test isn't just a fuel consumption test. It's an indication of how much power the engine is making, although in a rather indirect way.

The DME uses a maximum power AFR at around 11.9:1. So using 137 l/hr of fuel means your engine is sucking in around 1200 kg/hr of air. That's what a healthy M5 engine making around 400 HP flows. I suppose the engine could use 137 l/hr of fuel and suck in a lot less air for some reason but that should be obvious, e.g. black smoke under full power, fuel trims way off, terrible fuel consumption.

I just don't see any indication there is anything wrong with your engine. Why do you think it is down on power?

There are some other tests you could try. Do you have access to one of the accelerometer-type performance meters like Tesla Gtechpro?

And there are roll-on tests like this although they are not very accurate:
http://www.m5board.com/vbulletin/e39-m5-e52-z8-discussion/121622-80-120-kph-4-8-sec-4th-gear.html

Check out this thread on doing a compression test as I found it a bit tricky:
http://www.m5board.com/vbulletin/e39-m5-e52-z8-discussion/69610-tech-how-accurately-compression-test-s62-engine.html

I read that post yesterday¡¡

I´ve just bougth a compression test kit...

I´ll try to test it this weekend...

The accelerometer is something that is very rare in our country for a normal user...but I´ll ask a couple of friends...
 

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What was the sucked air temp in inpa when you did the dyno run?

My M5 made an extra 9 rwhp on a dyno just by letting the sucked air temp go down from 40 to 30 degC.
 
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