Testing the Condition of the DISA, "Adjuster Unit" on BMW M54 M52 Engines

Whilst replacing the Crank Case Ventilation Valve, I removed the DISA valve as it makes getting access to the CCV a lot easier but also allows you to check on the condition of the DISA itself.

The purpose of the DISA is to raise the low and midrange torque "and" raise the top end power output. It is present on E36, E46, E39, E60 and Z4's with the M54 or M52 engines. It's a valve that opens or closes intake ports depending on the load.

Here is short video I made showing how to check the condition of the DISA and the various levels of failure.

Check back when I'll write up some tips and additional photos, on replacing the CCV, that haven't always been detailed on most other DIYs..

H&R Sway / Anti roll bar Install & Opinions

I'd recently purchased H&R sway/anti roll bars as I'd heard they had a bigger impact on improving a cars handling than springs and shocks.  I had at approx 65k miles had H&R Cup kit spring & shock combo installed on my E46 along with having all the relevant suspension bushes replaced.  There was no deterioration in ride comfort, but did it improve the handling?  Only when you were really pressing on, but the the car did feel smooth and progressive on the track (Knockhill).

After installing the the H&R sway bars, there was an instant improvement, noticeable even in everyday driving.  The car felt much flatter through the corners, the front end seemed much more sensitive ie more willing to turn in, to such a great extent that I had to consciously modify my driving style by being much more gentle with my inputs.  But after a week, I quickly became accustomed to it, and don't have to "think" about my steering inputs.

Bear in mind, you can set the level of stiffness of the bars by connecting up the end link to different holes at the ends of the bars, and thereby affect the cars tendency to understeer or oversteer.  I set mine up to increase oversteer, (in  fact to maximum oversteer), FULL SOFT at the front, and FULL STIFF at the rear, as I've always felt that the 330ci is a heavy car, set up for safe understeer and not so willing to turn in.  However after a few weeks, I set the front to its middle setting. 

Here's a link to UUC's website that explains sway bar setup which i found useful:
 http://store.uucmotorwerks.com/articles/swaybar_setup.htm

Here's a few DIYs i found useful.  The first is an excellent video by Bav Auto, and the second link is useful in showing how to disconnenct the end link with the help of the factory vice locking pliers.

http://www.youtube.com/watch?v=KwZfLWwB1uM

http://forums.bimmerforums.com/forum/showthread.php?1686784-DIY-Front-Sway-Bar-Stabilizer-End-Link


My tips for the install:

(1)   Jack up both sides of the car, so both wheels are off the ground.  DO NOT jack up only one side and remove and install the bar.  For the front bar I only jacked up the right wheel, and managed to swap out the bar with the left wheel still on the ground.  After completing the install there was a little knocking coming from the front left especially as I went over bumps in the road.  I think with one side of the suspension/bar loaded and one side unloaded this probably caused and uneven and excess load/pressure being place on the left end link and caused it to fail.  I replaced it with new Lemforder end link and all was good.

(2)  For the rear bar all the DIYs seem to show the removal of the end link from below, but it is incredibly tight access that way, and I think it would be very frustrating.  Instead I jacked up the rear of the car and placed it on jack stands, and removed both rear wheels.  The picture below shows how much easier it is to get access to the end link bolts that sit above the rear wishbone:

 

Any questions or comments, fire away.