S50B32 power band question

[base146ball]

The car starts and idles great driving under 30 % throttle also feels very promising. As soon as you get into 100 % throttle it feels like something is holding the car back. As if you were limiting it somehow. Now for the weird part as soon as you get above 5000 rpm the car runs great pulls very hard and the more it revs the better it feels. Anyone have any idea what could be causing this or does the car usually feel like this??

The motor is in a 1988 E30 M3, stock fuel system, with an oil cooler and upgraded radiator. The exhaust is a Y pipe at the headers to a single 3" resonator to one 3" tube back to a muffler with a 3" inlet and two 2.5" outlets.

Please let me know your thoughts.

Thanks You

[gobuffs]

1. pull the codes. sounds like you might have a Vanos problem.
2. other people will say the stock E30 M3 fuel pump is sufficient, but the B32 requires 5 bar. I'd check your fuel pressure....OTOH, you'd have more problems at the upper RPMs if fuel was insufficient.
3. check you electrical system and muake sure your grounds are clean and making good contact.

[Jason89i]

1. pull the codes. sounds like you might have a Vanos problem..

agreed. take it to the dealer and have an experienced person hook it up to the gt1 and see whats going on with the engine running. vanos units on the s50b32 have been very problematic in europe. I too had a both vanos units stuck at "0". both solenoids needed to be replaced. best of luck. cheers, jason

[digger]

S50B32 should come on strong by 2200rpm peak torque at ~3200-3500rpm and pull hard to 7k sounds like vanos for sure

[base146ball]

Thanks for all of the feedback guys I have had the car hooked up to a snap on unit that is supposed to be very expensive and no codes showed on that. Do you guys think the bmw computer will read differently.

[sharksforthecup]

unplug the vanos solenoid to see if it is the vanos

[Jason89i]

...............I have had the car hooked up to a snap on unit that is supposed to be very expensive and no codes showed on that. ..

get it hooked up to a gt1 or something that can read ALL sensors while the car is running.

when mine was hooked up, you could see all the sensor data that the dme was reading.....including the tdc and vanos positions.

cheers, jason

[mattdk318i]

im starting to notice a pattern in these DOHC threads. Theres been 4 or 5 threads about S5X's "dieing"
What FPR are you running? Could be vanos of coarse... but im curious

[tubby17s]

Standard fuel pump is not good enough. youll need to upgrade it to the higher pressure one. pull one out of a m3 3.2ltr and hose clamp it onto you existing fuel pump frame.

Or run a dual pump set up with a surge tank because you'll have issues later down the track and may as well kill two birds with one stone.

[tubby17s]

Standard fuel pump is not good enough. youll need to upgrade it to the higher pressure one. pull one out of a m3 3.2ltr and hose clamp it onto you existing fuel pump frame.

Or run a dual pump set up with a surge tank because you'll have issues later down the track and may as well kill two birds with one stone.

[base146ball]

ok guys well I have installed a Walbro 255 I had and the car is still having the same issues. I took a look at the Vanos today and noticed some silicone around the exhaust solenoid cap. So I am figuring the car has a Vanos issue, I think I can get the car into the shop on Thursday. I will keep you guys updated but I can not wait until it is running right! Does anyone know about how big of a difference the car will have in power?? Also me driving it without it working is not hurting anything right?

[Jason89i]

.........I took a look at the Vanos today and noticed some silicone around the exhaust solenoid cap. So I am figuring the car has a Vanos issue, I think I can get the car into the shop on Thursday.

frank -

the vanos solenoids problems are VERY common. my old motor had the solenooids serviced before the 56k mile mark and were dead. from what ive heard (not first hand experience) the vibration of the motor will fatigue the thin wires and pull them off the contacts. if you open the cover (the one thats usually siliconed like yours) you can check for loose wires and solder them back on. i think the new service manual calls for filling the cavity with silicone to keep the wires stabil........that is just hear-say though.

i thought my car felt healthy from 2200 to redline. could easily pull an 07 mcoupe in a drag race down the main strait.

cheers, jason

[m3_eater]

frank -

the vanos solenoids problems are VERY common. my old motor had the solenooids serviced before the 56k mile mark and were dead. from what ive heard (not first hand experience) the vibration of the motor will fatigue the thin wires and pull them off the contacts. if you open the cover (the one thats usually siliconed like yours) you can check for loose wires and solder them back on. i think the new service manual calls for filling the cavity with silicone to keep the wires stabil........that is just hear-say though.

i thought my car felt healthy from 2200 to redline. could easily pull an 07 mcoupe in a drag race down the main strait.

cheers, jason

EDIT: nevermind, I just realized he was asking about an s50b32, not a US S50. Single VANOS == different animal!

[erik325i]

Or run a dual pump set up with a surge tank because you'll have issues later down the track and may as well kill two birds with one stone.

So, with the dual pump setup, you run the stock in-tank pump to the surge tank, and then an in-line (Walbro) pump? What size Walbro pump should I run?
This setup will provide sufficient fuel pressure for the b32 motor?
I have a nice surge tank already, just need to install it.

Erik

[base146ball]

Ok guys I took the car to the dealer and as I pulled in everyone stopped what they were doing lol. Well the computer says that the Vanos is working great and that there is really no codes with the motor that it could find. It did have an O2 sensor code but we cleared it and it never came back. I was told by a few guys there it could be a faulty HFM. If you guys have any idea on what else it could be please let me know.