Dyno results

[M4YTY]

So, after swapping the M50 in i had my car on the dyno today.
Stock M50, custom intake, custom rear exhaust with stock 325 cats etc, running on normal supermarket 95 RON fuel (super is too expensive here at the moment! 98RON)

Came out with 173.2HP at the crank (150.9rwhp) and 163.2 Lbft or 221 NM torque.

Seems rather low to me. Think im gunna check the timing this week. Power curve was nice and smooth though so no starvation as i thought.

Anyone else have any results of an M50 vanos motor?

I'll post the graph up later on tonight

[Philly]

from a quick google search, BHP figures for the M50 should be in the range of around 185-190ish..... so yeah it looks like your missing a few somewheres...
Does it run nice and smooth?

fwiw, some dyno's are finicky anyways... if you try again soon, find a different type of dyno and see what results you get.


can't wait to get mine dyno'd

[mohaughn]

I wouldn't sweat the calculation on what it thinks your crank power is.. Most of the time I see people use 18% drivetrain loss for BMWs.. Which would put you up at 177 at the crank... M50 horsepower is published as 189hp at 5900 rpm...

I'd say that is close enough... Different dyno's, different locations, weather conditions, etc.. all affect performance. Not to mention the lower octane fuel.

Intake and exhaust are not going to get you much performance gains without tuning, and that tuning would need to be for high octane fuel.

[M4YTY]

Well, ever since i put the engine in ive thought it feels "choked" Sometimes it picks up and really flies! Pity it didn't pick up on the rollers! (typical) It's a really noticable difference. Even my GF noticed it without me saying anthing so there is defo something wrong. Im going to change the vanos unit to spring plates soon to cure the rattle so I will do the timing properly as no-one gets it right without the special tools. I checked the vanos solenoid tonight and that works so maybe its a sticky vanos adjustment unit. We'll see

[mohaughn]

If you suspect a vanos problem you can get in contact with this guy- drvanos.com. Not sure how he handles international orders, but paying in Euros will give you a nice break from what we pay here in the states...

Your title says you are a BMW tech, do you have access to a breakout box? I had some performance issues and we were able to troubleshoot all of the sensors in one shot by recording all of the data coming into the DME. Helped us figure out the DME/tune was my problem and not a sensor. My problem was sporadic so having the breakout box hooked up and recording all of the time helped us figure out the issue.

[BimmerBum]

My 99 2.8 (M52tu) Z3 Coupe dynoed at 169hp and 171ft lbs at the wheels... stock. Mustang dyno, South Florida heat.

That said, from what I understand the vanos unit could be your whole problem. I have a stage II kit from Dr. Vanos waiting to go into my S50ti, it makes minimal power in the low end but comes alive in the high RPM. Do you have any fault codes?

[M-technik-3]

Does seem slightly soft my E30 M50 was doing 169 at the wheels average depending which chip I ran.

When I went to S50 cams it jumped by 8 hp by the Tq suffered, so I compensated by changing from a 3.25Lsd to a 3.46lsd. I have not been on the dyno in 5 years wonder where it stands now.

[96cali]

Originally Posted by BimmerBum

My 99 2.8 (M52tu) Z3 Coupe dynoed at 169hp and 171ft lbs at the wheels... stock. Mustang dyno, South Florida heat.

Assuming the 18% drivetrain loss (I've heard more like 15% on manual shift Bimmers, but whatever) that puts you at 199.4 hp at the crank. Dang good for humid Florida. IMO our M44's like cooler dryer weather like 60 degrees, not sure about the 6's. I got 36mpg in weather like that this spring!

BTW bimmerbum, should you ever want to swap out your 2.8 drivetrain give me a shout. I'm gonna try and locate a wrecked 2.8 Z3 this fall for a drivetrain swap. Also hope to get the brakes which is why I held off from your brake pad/rotor deal.

[M4YTY]

ive got no fault codes but ive read all of the info from the sensors and theres somethin up with my oxygen sensor. It should fluctuate between 0.1 and 0.9V. But, its sits bang on 0.46 (fail safe) and doesn't move. If the heater relay for the sensor is pulled out and put back in, the readings fluctuate as normal for 10-15 secs then settle to 0.46 again. Ive put a new oxy sensor in and its just the same. Had no time to work on the car lately. Need to start checking wiring etc. Any one seen this before? I aint!

[M4YTY]

Well, two of my mates had their cars on the same dyno yesterday. One was a 330ci and the other was a Vauxhall vectra 2.5 V6. Both were 20bhp down from previous dyno rus on a different dyno. Starting to think the dyno is out. There has been romours for a while that it was reading low. Maybe they are true. Who knows. Still, doesn't explain my 02 sensor readings. And my vanos unit sounds like SH*T. Great!