[eclipsor]

I have a couple quick questions for you guys. I have a 2008 335xi coupe and I will be installing a Helix FMIC, AR catless DPs, and AE catless exhaust this weekend (on jackstands/ramps (read: no lift)). I'm wondering how much different the installs will be on the AWD, as opposed to the RWD. I'll be using the following three DIYs, as well as the factory service manual + some years of mechanical experience...

http://www.e90post.com/forums/showthread.php?t=104333
http://www.e90post.com/forums/showthread.php?t=91461
http://www.e90post.com/forums/showthread.php?t=79514

Please let me know if there are other DIYs that are more suited for my exact application. I'm thinking that the downpipe install will be the only one with any significant differences from the DIYs.

Also, I have a set of KW V3s sitting around, ready to be installed. Would it be beneficial to install the suspension at the same time (i.e. will I have to take off front suspension components to access the DPs on my xi)?

Thanks in advance for the help.

P.S. Hopefully I can get onto a dyno sometime this week for a baseline run before I start going crazy with the mods.

[cn555ic]

The only difference will be the DPs...which would be more difficult...other than that it should be pretty straightforward...Good luck especially since your doing it with jack stands! If you finish everything after the weekend, your a champ!

[jpsimon]

Unless you cut one of the stock downpipes in half with a sawzall you'll need to remove some suspension bits

[JoeyFiasco]

Originally Posted by jpsimon

Unless you cut one of the stock downpipes in half with a sawzall you'll need to remove some suspension bits

you're joking.. really?

[jpsimon]

not joking, there isn't room to remove the downpipes without doing one of those two things. We cut one of mine in half instead of removing the axel and such... axel removal/install is a pain in the ass.

[eclipsor]

Originally Posted by jpsimon

not joking, there isn't room to remove the downpipes without doing one of those two things. We cut one of mine in half instead of removing the axel and such... axel removal/install is a pain in the ass.

Ugh... removing suspension components is one thing, but removing one of the axles is another. I guess I will just cut the damn pipe. The only time I will be removing the axles is when I change my clutch.

[jpsimon]

it's more fun to cut it anyways

[eclipsor]

How hard is it to get the AR DPs up into their final destination without taking out the axle? I'm guessing it's the cats that make the stockers hard to remove, eh?

[JoeyFiasco]

Originally Posted by jpsimon

it's more fun to cut it anyways

Jesus.. you went to town on those. if that if what has to be done with every DP install on a Xi you guys get props.

[jpsimon]

Originally Posted by eclipsor

How hard is it to get the AR DPs up into their final destination without taking out the axle? I'm guessing it's the cats that make the stockers hard to remove, eh?

My UR ones are 2.5", they went right back in with no issues. I can't comment on the AR's. But like you said, it was the cats that were the issue getting the stock ones out

[eclipsor]

Well... HO LY SHIT... my car is finally back together and I'm in love.

I installed the Helix FMIC and the AE exhaust myself, then got to work on the downpipes. I cut the stockers in half (I now regret that) before removing the axle and bearing case, which turned out to be a big mistake. Why? Because I couldn't get the axle out of the bearing case or the hub. That fucker was in there good and I had absolutely no luck extracting either end. Obviously there was no going back, at that point, because the stock dowpipes were sitting on the garage floor in pieces. I was getting pretty pissed off and I didn't want to break anything, so I ended up just putting the car up onto my trailer and taking it to a shop near my house.

Originally Posted by jpsimon

My UR ones are 2.5", they went right back in with no issues. I can't comment on the AR's. But like you said, it was the cats that were the issue getting the stock ones out

They had to remove the axle, drop the sub-frame, and lift the engine in order to get the big-ass AR downpipes up onto the turbos.

The end result is definitely noticeable. The sound is quite intoxicating and my butt dyno has registered a significant increase in power (especially high in the rev range). The exhaust sounds SO much meaner and more beefy than stock. I was surprised to actually hear less of a "gurgling" sound at low speeds (part and off-throttle), which I'm (incorrectly?) attributing to the decreased back pressure.

QUESTION #1: The passenger side hose that came with my Helix FMIC doesn't seem to be optimal piece for the job. It's a straight section of hose, if I remember correctly, and it actually should have a slight (5 degree, maybe) bend in it. I made it fit, but the hose is actually deforming (crinkling) because it's being forced to bend slightly. This is definitely not ideal and I'm trying to find a replacement that's better suited for the task at hand. Has anyone else experienced the same issue?

QUESTION #2: The Helix FMIC feels to be about three times heavier than the stock unit, yet it's still being held in place by the same two (tiny) screws. I'm very worried about this intercooler dropping out of the car if I hit a big pothole. I think I'm going to try to reinforce the FMIC with some heavy-duty zip ties. Has anyone else had a similar concern?

Thanks!

[cn555ic]

Originally Posted by eclipsor

Well... HO LY SHIT... my car is finally back together and I'm in love.

I installed the Helix FMIC and the AE exhaust myself, then got to work on the downpipes. I cut the stockers in half (I now regret that) before removing the axle and bearing case, which turned out to be a big mistake. Why? Because I couldn't get the axle out of the bearing case or the hub. That fucker was in there good and I had absolutely no luck extracting either end. Obviously there was no going back, at that point, because the stock dowpipes were sitting on the garage floor in pieces. I was getting pretty pissed off and I didn't want to break anything, so I ended up just putting the car up onto my trailer and taking it to a shop near my house.


They had to remove the axle, drop the sub-frame, and lift the engine in order to get the big-ass AR downpipes up onto the turbos.

The end result is definitely noticeable. The sound is quite intoxicating and my butt dyno has registered a significant increase in power (especially high in the rev range). The exhaust sounds SO much meaner and more beefy than stock. I was surprised to actually hear less of a "gurgling" sound at low speeds (part and off-throttle), which I'm (incorrectly?) attributing to the decreased back pressure.

QUESTION #1: The passenger side hose that came with my Helix FMIC doesn't seem to be optimal piece for the job. It's a straight section of hose, if I remember correctly, and it actually should have a slight (5 degree, maybe) bend in it. I made it fit, but the hose is actually deforming (crinkling) because it's being forced to bend slightly. This is definitely not ideal and I'm trying to find a replacement that's better suited for the task at hand. Has anyone else experienced the same issue?

QUESTION #2: The Helix FMIC feels to be about three times heavier than the stock unit, yet it's still being held in place by the same two (tiny) screws. I'm very worried about this intercooler dropping out of the car if I hit a big pothole. I think I'm going to try to reinforce the FMIC with some heavy-duty zip ties. Has anyone else had a similar concern?

Thanks!

Regarding the FMIC weight issue, I was also concerned with the weight of these large fmic and the lack of a real support....Waited for a while for some vendor to finally come out with a support system to pull the trigger...Although you and I may feel uncomfortable about this, there hasn't been one issue that I have heard about the IC falling out.

[TurboBimmer]

Yeah, I was really surprised that the IC is fixed place by two tiny screws (what's more, screwed into plastic... ).

But I guess it's just as much the IC pipes which hold it in place. On my Forge IC, the OEM tubing is replaced by silicone ones, which are a very tight fight, secured by T-clamps.

[BayerischeMW]

OT: Autobahn335i, could you (in a different thread) post your thoughts on the Forge FMIC (power, temperature, pressure drop and install)?

[JayML]

was it this much trouble to get the ar pipes in because the car is an xi? or thats what everyone goes through when they put downpipes in the n54 motor

does it matter if your coupe or 4 door as well

[eclipsor]

Originally Posted by slapmyfro

was it this much trouble to get the ar pipes in because the car is an xi? or thats what everyone goes through when they put downpipes in the n54 motor

does it matter if your coupe or 4 door as well

Just XIs have to deal with this... and I don't think it has anything to do with the number of doors.

[Alex@AKMotorwerk]

Originally Posted by slapmyfro

was it this much trouble to get the ar pipes in because the car is an xi? or thats what everyone goes through when they put downpipes in the n54 motor

does it matter if your coupe or 4 door as well

xi's/xdrive are definitely more trouble than the I's... coupe and 4 door are similar, it's the i and xi that differs.

[stimpy]

Originally Posted by eclipsor

Well... HO LY SHIT... my car is finally back together and I'm in love.

I installed the Helix FMIC and the AE exhaust myself, then got to work on the downpipes. I cut the stockers in half (I now regret that) before removing the axle and bearing case, which turned out to be a big mistake. Why? Because I couldn't get the axle out of the bearing case or the hub. That fucker was in there good and I had absolutely no luck extracting either end. Obviously there was no going back, at that point, because the stock dowpipes were sitting on the garage floor in pieces. I was getting pretty pissed off and I didn't want to break anything, so I ended up just putting the car up onto my trailer and taking it to a shop near my house.


They had to remove the axle, drop the sub-frame, and lift the engine in order to get the big-ass AR downpipes up onto the turbos.

The end result is definitely noticeable. The sound is quite intoxicating and my butt dyno has registered a significant increase in power (especially high in the rev range). The exhaust sounds SO much meaner and more beefy than stock. I was surprised to actually hear less of a "gurgling" sound at low speeds (part and off-throttle), which I'm (incorrectly?) attributing to the decreased back pressure.

QUESTION #1: The passenger side hose that came with my Helix FMIC doesn't seem to be optimal piece for the job. It's a straight section of hose, if I remember correctly, and it actually should have a slight (5 degree, maybe) bend in it. I made it fit, but the hose is actually deforming (crinkling) because it's being forced to bend slightly. This is definitely not ideal and I'm trying to find a replacement that's better suited for the task at hand. Has anyone else experienced the same issue?

QUESTION #2: The Helix FMIC feels to be about three times heavier than the stock unit, yet it's still being held in place by the same two (tiny) screws. I'm very worried about this intercooler dropping out of the car if I hit a big pothole. I think I'm going to try to reinforce the FMIC with some heavy-duty zip ties. Has anyone else had a similar concern?

Thanks!

#1 - I'm not sure if it's the same issue as we had but it sounds very similar. What we had to do to get rid of the deforming/crinkling was pull the silicone hose up higher on each end and it straightened out any crinkling.

#2 - I agree however I haven't had an issue yet (or read of one)

[zsapphire7]

thats crazy... im so glad i didnt get an xi haha....

[import36]

geezus...i'll be installing the same exhaust and downpipe combo soon. i feel really fortunate at this point to not have an XI...especially since i'll be doing this in my garage on ramps/jackstands.

[Kevin@AKMotorwerk]

the axle does not have to be taken out, and the dp doenst have to be cut, although on jackstands thats probably the easier route

[eclipsor]

Originally Posted by Kevin@AKMotorwerk

the axle does not have to be taken out, and the dp doenst have to be cut, although on jackstands thats probably the easier route

I have a hard time believing that.

So, if you don't remove the axle and bearing case, do you drop the subframe and lift the motor.