135i power issues

[Ikes]

Hey Guys,

I am in need of some advice. Irecently had my car on the at WRC and shockingly it only 173.9 on the wheels. this concerned me a bit and the car was booked in at BMW and got the car back feeling slightly better. I then found out that Evolution 2 motorsport is who BMW use when they want to dyno cars. I then took my car there and did a dyno run. Needless to say "SHOCKING". From 4000 rpm the cars torque drops from around 400 to 240 at 6500 rpm surely something is not right. BMW however claiom that they are picking up nothing with the car on their computers.

Any advice on what you think it could be and which dealership in the JHB area would be able to help.




Attached a copy of the dyno printout.

 

[Baracus]

Hey Guys,

I am in need of some advice. Irecently had my car on the at WRC and shockingly it only 173.9 on the wheels. this concerned me a bit and the car was booked in at BMW and got the car back feeling slightly better. I then found out that Evolution 2 motorsport is who BMW use when they want to dyno cars. I then took my car there and did a dyno run. Needless to say "SHOCKING". From 4000 rpm the cars torque drops from around 400 to 240 at 6500 rpm surely something is not right. BMW however claiom that they are picking up nothing with the car on their computers.

Any advice on what you think it could be and which dealership in the JHB area would be able to help.




Attached a copy of the dyno printout.

Your peak power of 191wkw 5500 rpms on the Evolution Motorsports graph seems within normal limits, stock N54's/N55's usually dyno at around 190-205 wkw's at the reef with correction factors. However just having a quick look at the graph you do seem to have a torque curve that drops off a bit more than usual after 4000 rpm's, quite strange as power is a function of torque and engine speed?? So theorectically if torque is dropping off like that your peak power should also be a bit lower than normal? :thinking: But hey I'm not an expert, perhaps George or Sherwin could comment? What did the power curve of the 173 wkw's run at WRC look like? Can you perhaps post that graph as i think the one from Evolution Motorsports could be a bit misleading? Just checked my old 135's dyno at Snail and peak torque was 412nm but the difference was that at 6500 rpms I was still at 280nm, however comparisons are not really useful as that was on a another dyno, under totally different conditions

I'd start by checking to see if your diverter valves are clicked in correctly (arrows must match up), you could be having a problem maintaining boost at higher rpm's?

(BTW I suggest you remove your details and reg number from the image, if u decide to mod later u definitely dont want BMW snooping around!)

 

[Ikes]

At higher RPM the car doesn't seem to respond as it would at around 2500 - 3000 rpm. iwould have thought the torque should hold out a bit longer. Attached is the dyno chart from WRC and again the torque drops off to around the 240 mark. Will give the DV a check to see. Question, does the 135 generally dump quite loud?



Thanks for the heads up. How do i replace the pic?

 

[roboman]

I know its a strange question but what is a divert or valve and where does it sit?

 

[Twinz]

I know its a strange question but what is a divert or valve and where does it sit?

Read here:
http://www.forgemotorsport.com/content.asp?inc=product&cat=020301&product=FMDVBM35

Left Picture: Stock DVs in the stock charge pipe. Right picture: Forge DVs in the Stett charge pipe

Left pic: Forge DVs can also fit straight into stock charge pipe. Right pic: Or you can choose a Blow off Valve fitted into a Stett charge pipe:

The DVs or BOV fit on the right-hand side of the engine bay:

 

[Baracus]

At higher RPM the car doesn't seem to respond as it would at around 2500 - 3000 rpm. iwould have thought the torque should hold out a bit longer. Attached is the dyno chart from WRC and again the torque drops off to around the 240 mark. Will give the DV a check to see. Question, does the 135 generally dump quite loud?



Thanks for the heads up. How do i replace the pic?

Now this graph makes more sense, the scale and sharp curve in the Evolution Motorsports one was a bit misleading. Your peak power definitely looks like it’s a bit lower than normal and confirms the sharp drop off in torque you seeing. Whatever is causing to loose 20wkw+ should throw a code though, have you had anybody from the forum read the car with a BT cable? It’s definitely worth double checking as some the BM techie's are really incompetent and are often just plain lazy to check properly, as I recently found out when I had to have my brake pads replaced! Warning light went off 5 times after replacing the pads, they changed the sensors for a second time but still kept getting the red light? Eventually I sorted it out myself with my BT cable, they hadn’t set the remaining wear % in CBS parameters correctly:flyfun:. Unfortunately I’ve only got an enthusiast BT cable which means its VIN locked to only 3 vehicles, however I strongly suggest you contact one of the tuners on this forum, maybe OB or Sherwin and they can read any codes and also do some logs of boost and ignition advance etc. with the professional BT cable

 

[Ikes]

Thanks Baracus.

I got the car booked in at JSN tomorrow so we'll see what they say. Will definitely contact one of the tuners to see whats happening. Can't go ahead with plans with the car in this state.

---

I know its a strange question but what is a divert or valve and where does it sit?

Read here:
http://www.forgemotorsport.com/content.asp?inc=product&cat=020301&product=FMDVBM35

Left Picture: Stock DVs in the stock charge pipe. Right picture: Forge DVs in the Stett charge pipe

Left pic: Forge DVs can also fit straight into stock charge pipe. Right pic: Or you can choose a Blow off Valve fitted into a Stett charge pipe:

The DVs or BOV fit on the right-hand side of the engine bay:

DV's look interesting. Any idea what they cost for the N55?

 

[Twinz]

There are some for sale on this forum.

Rennzport has a set as well. Give Revo a PM.