hatterasman

I responded from my phone earlier...now back at the computer I went through the pics I took to refresh my memory...as my Dad used to say "old people forget"

I've attached an image of the block side that I don't think I posted before. I think you can see that the pipe wants to hit the bolt for the bracket holding the turbo oil lines as well as their heat shield. I bent this slightly to get it out of the way to get the extra rotation needed.

Alignment is tedious because tightening up the v-bands moves the pipes slightly. If you can get them close tightening up the v-band bolts helps to pull them into alignment with the exhaust manifold. The issue I had was this changed the angle of the flange meeting the exhaust. I had to loosen the v-bands and re-position the pipes a couple of times before I got them to pull up tight to the exhaust manifold at the proper angle to meet the exhaust flanges on the other end. I found that I had to leave the flange end loose, because inserting bolts into the flange kept the DP from pulling up to the exhaust manifold. First time I tightened up the v-band bolts, they appeared to be tight. I removed the flange bolts to recheck alignment and found that the v-bands were loose because the exhaust system was pulling on the DP.

I'm going to be working on the car this weekend (M5 brake install, yea!) if there is a measurement I can take to help you verify the length of your pipe versus mine I happy to try.

Jeff

apaisncsu

Sorry for delayed response. It has been a busy week.

After I made my last post, I took another look and played around. I too found that I had to bend the bracket, but I also replaced the small bolt that is used to attach the oil line heat shield to the bracket with a bolt with a shorter head since it was the location of the bolt head that limited the rotation of the rear DP.

The new bolt with the flat black head is shown installed below (rear DP not installed). Bending the bracket that the bolt is screwed into also allowed for insertion of the rear DP after the front DP had been installed. Previously, I had to insert the front and rear DPs into the space together, as is described in other threads.




The pic below shows the rear DP installed and how close it is to the bent bracket with the replaced shorter-head bolt.




As hatterasman mentioned, the gap between the rear DP and the block is very small. This view is looking up on the left (driver side) of the rear DP. The gap between the DP and oil line on-line heat shield is even tighter, but there is a gap.




Here is the final installed product from directly below and from slightly to the right (passenger side).






Once I got the DPs installed, lining up the mid-pipes presented another challenge. When I pulled the mid-pipes toward the front of the car, there was a gap between the front DP and its respective mid-pipe when the rear DP was sitting against its respective midpipe. Also, I was able to line up the front DP (on the right above) almost perfectly with its respective mid-pipe, but I had to twist the rear DP mid-pipe to get the bolt holes to line up with the rear DP. Luckily the amount of necessary rotation was pretty small and the pipes are long enough to allow for the rotation. Once I got the rear DP bolted to its mid-pipe, I torqued the front DP bolts to get it to mate to its midpipe which put a bit of compression on the rear DP connection with its midpipe. In the end, I am not sure that the fit could have been any more snug.

The upstream O2 sensors presented another challenge. There was only enough slack to allow for installation into the OEM DPs and I need a bit of extra slack to install the rear DP sensor. After working my way down to the sensor leads from above, I unclipped them from the head and pulled a bit of slack from the back side of the engine where they route to the connection near the intake manifold. I still had a hell of a time getting the rear DP O2 sensor tightened with both DPs installed. As hatterasman previously mentioned, a 22mm crowsfoot wrench came in very handy here. Though, I had to push the rear vband bolt to the top of the flange to allow for enough room for the crowsfoot to rotate.

Reinstallation of all brackets, wheel well shield, skid plate, and splash guards was still another 90-120 min of work after the pipes were installed and tightened.

Overall, I had a few bumps along the way since I am not very experienced with such installs, but the technical challenge was not that difficult. As hatterasman pointed out, the video by AR about installing the DPs on a 335i was helpful and had some good pointers. Also, there was [thankfully] no need to drop the axle, steering rack, or subframe. Prior to this install, the most challenging work I have done is replacing the water pump on my old 2006 e91 325xi. If I can do this job, any decent home-mechanic with decent tools should be able to knock it out.

Thanks again to hatterasman for the inspiration to do the job and to AR for making some DPs for the e61. Now on to the JB4 install....

Jerry1847

Thank you for the write up!

ordered my DPs last week along with some other goodies (dci, oil catch, charge pipe). Can't wait to install!

how was the sound change? Any noticeable changes?

hatterasman

See sound clips in post #13. Good luck with your insall.

Jerry1847

Was that at closed loop on cold start or with a warm engine?

hatterasman

open loop...cold start.

Which pipes did you order?

Jerry1847

Nice, I'm excited. I ordered the AR design from N54tuning.com.