DIY and Parts: Mr5 Intake System (Cold Air Intake) for the 135i

[thetaobear]

This is for the 135i N54

* Goal: Get cold air from both the OEM intake box and air from near the bumper.

* Motivation: I had DCIs. But the noise (besides the turbo spooling) is quite annoying and unpleasant. Also, when you run multiple WOTs and at low-speed situations, hot air soaks. (you can find more information by doing a search). "Mr5 intake" system has shown to reduce stress on turbos, maintains more consistent air intake temps, and maintains near stock engine bay noise. The design is very similar to Dinan's CAI. If you are interested in the debate, don't do it here, but

The Debate
http://www.e90post.com/forums/showthread.php?t=352077

Dynos
http://www.e90post.com/forums/showthread.php?t=549854

Was it worth it?
Yes- I have a JB4 tune. With the stock airbox, I felt the power loss and the engine demands more air
Beats DCI because...
+ quieter in-cabin noise coming from the engine bay
+ colder intake air temperature through multiple runs
+ stock look
Beats stock because...
+ more HP due to my tune. It definitely pulls a lot harder than stock intake. Performs similarly with DCI, but, again, the noise and other benefits outweigh.

If you have a stock tune... I don't think it is worth it?

* Challenges: Mr5's original design works for E90/E92 because there is more room.
With the E82,
- we have a lot less space.
- I do not want to modify the wheel wells, steering fluid container, etc.
- and have that OEM look to increase the possibility of passing those pesky California Smog Checks

To get parts requires a lot of guessing game. But here it is
==========
- DIY
- Review and Impressions
- Hard Logs and Numbers (coming up!)
==========
What you need:
* Air Filter- K&N RU-0610
* Duct -
http://www.mcmaster.com/#5499k243/=vzsymp
High-Temperature Blo-R-Vac Duct Hose for Dust 2-1/4" ID, 2-5/16" OD, Black, 3 ft. Length (5499k243)
* Flange:
http://www.aircraftspruce.com/pages/...uctflanges.php
10350-9
* 2.25-inch clamps

Magic number: 2.25 inches inlet and duct

Air Filter- K&N RU-0610
+ this fits EXACTLY between your wheel well and bumper
+ I wanted to use the BMS DCI but those are way too big
This is how I placed it:


High-Temperature Blo-R-Vac Duct Hose
+ This is the one that is flexible enough to snake through
+ 2.25 inches is the maximum-ish inlet diameter that can fit through everything

Same-ish DIY: http://www.e90post.com/forums/showthread.php?t=549965


DIY

Prerequisites:
- cowl
- air intake
- wheels
- wheel well

Step 1: Cut a 2.25 inch hole through the right side of your OEM intake box
- sand it the sides down first
- then use 2.25 inch drill to cut it (I suggest using a corded drill unless you have a powerful battery powered drill)


Step 2: Put flange through the 2.25 inch hole


Step 3: Attach the air filter onto your duct


Step 4: Take off your front driver wheel to get access to the wheel well


Step 5: Place the filter right between the wheel well and front bumper. You will see there are a few air holes all ready to go for air to inlet for you. I put it this way so it can fit:


Step 6: Make sure you carefully snake the pipes out on top.


Step 7: Attach your duct to the flange that you attached to your OEM airbox

This is the final result:


Comments and suggestions welcomed!

==========
Review and Impressions
Here I will focus more on the "real world" feels.

Mr5 outshines the stock air intake in terms of power.
Mr5 outshines the DCI intake in terms of smoothness and consistency.

Power
The car feels more powerful than stock air box hands down. I have LSD and JB4; with this intake, my tail wags (fun). With the stock intake, it doesn't as much. This feeling is similar to the DCI. I believe the top torque/HP feels about the same as DCI. However...

Smoothness
After traffic or driving windy roads, when I WOT with the DCIs, I feel some sluggish/hesitation at higher RPMs. I believe this is because of the inconsistent oxygen that the DCI sucks in during slow traffic, etc. since all the air is coming from inside of your hood with all that hot air mixed in. This is extremely prominent during traffic driving. With the Mr5 intake, even through traffic, my car pulls nicely; DCIs feel sluggish at times. Just for reference, the weather here is 60-70 degrees F and 50-70% humidity.

Consistency
The consistency of the pulls are very similar to the stock air intake, but, now, with more power. The DCIs, again, feel sluggish after a few pulls/slow driving/traffic.

==========
Hard Logs and Numbers

Coming up!

Credits to Mr. 5

[MightyMouseTech]

The stock airbox already gets fresh air from the front of the car?!?!?

[thetaobear]

Yes, but not enough. The stock intake box is a bit restrictive for non-stock tunes. This is why you need another air inlet (or what most use, dual cone intakes)

[Solo_M_Tech]

Has this been done to an N55? Any gains possible with it?

[GR1P]

classy.....

[e36addict]

Uhm.. what? That looks ridiculous.. and pointless. Just get a BMS DCI lol

[thetaobear]

Not sure if this has been done for the N55 engine. This is for the N54

[MuNkY6913]

Curious. I didn't read any of the other thread you linked. Did you do any logs before and after? Did you see boost targets or afr or timing being affected without this mod that was fixed by doing it? How much of a drop in ait compared to the dci did you get? If you ever want to undo it, keep me in mind. Have a stock airbox to sell.

[spxxx]

Originally Posted by MuNkY6913

Curious. I didn't read any of the other thread you linked. Did you do any logs before and after? Did you see boost targets or afr or timing being affected without this mod that was fixed by doing it? How much of a drop in ait compared to the dci did you get? If you ever want to undo it, keep me in mind. Have a stock airbox to sell.

How did this effect pwm or wgdc at similar boost levels? Compared to DCI... I saw higher wgdc with my Mr 5 Intake compared to DCI but I'm thinking of going back for the stealth look and cost iat

[Solo_M_Tech]

Originally Posted by e36addict

Uhm.. what? That looks ridiculous.. and pointless. Just get a BMS DCI lol

If the N54 Dinnan intake uses the same design, (in carbon fiber though) it must not be pointless.

[spain4065]

Better to go with upgraded inlets by forum member on n54 tech...check it out!

[ShocknAwe]

Originally Posted by spain4065

Better to go with upgraded inlets by forum member on n54 tech...check it out!

Have those inlets been dynoed yet for a car on factory turbos? Also, a HUGE difference in install difficulty. Intake filters are about as easy as it gets, whereas to do the inlets it requires tinkering with everything from PS reservoir and vacuum canisters to DPs.

On topic:
OP, I would look into running a 90-120 degree bent 3"+ aluminum pipe from the side of the airbox straight foward to a huge snub nose cone filter right behind the headlight. Reduce your restrictions and the length of the piping. Thermal wrap the piping (or maybe ceramic coat?) and you're good to go!

[spain4065]

IF you can install DP's then you can install inlets. Not rocket science. To each it's own, some people aren't too technically inclined. I'd rather have the best performing modification than to have a sub-par upgrade for some silicone bends for $500.

[ShocknAwe]

Originally Posted by spain4065

IF you can install DP's then you can install inlets. Not rocket science. To each it's own, some people aren't too technically inclined. I'd rather have the best performing modification than to have a sub-par upgrade for some silicone bends for $500.

Oh I totally agree with you. Though, ability levels differ so greatly here that I thought it was prudent to be blunt about what's involved so folks knew what they were getting into.

[thetaobear]

Originally Posted by ShocknAwe

Have those inlets been dynoed yet for a car on factory turbos? Also, a HUGE difference in install difficulty. Intake filters are about as easy as it gets, whereas to do the inlets it requires tinkering with everything from PS reservoir and vacuum canisters to DPs.

On topic:
OP, I would look into running a 90-120 degree bent 3"+ aluminum pipe from the side of the airbox straight foward to a huge snub nose cone filter right behind the headlight. Reduce your restrictions and the length of the piping. Thermal wrap the piping (or maybe ceramic coat?) and you're good to go!

Thanks a bunch! Yes, the huge snub nose cone filter is definitely another option and doesn't require inserting a filter through the wheel well. Thanks for the suggestion.

[thetaobear]

Originally Posted by spxxx

How did this effect pwm or wgdc at similar boost levels? Compared to DCI... I saw higher wgdc with my Mr 5 Intake compared to DCI but I'm thinking of going back for the stealth look and cost iat

I'll log it sometime this weekend! Read my updated impressions in the meantime. I really think Mr 5 intake does a better job with the IAT.

[froop]

I have a Mr5 style intake on my car. Quite similar to yours except I'm using a K&N Apollo filter. Right now it sits next to the power steering reservoir and I have a length of pipe to route it down into the wheel well but I haven't gotten around to doing it yet. It's been 2 years LOL. Maybe I'll do it tonight if I can be bothered.

But when I dyno'd it post install, from memory the car gained about 4-5kW. Same everything except for the intake. Given they dynos were taken on different days, but it was early autumn when the post intake dyno was taken so would have been reasonably warm still.

[e36addict]

Originally Posted by HooningB2G

If the N54 Dinnan intake uses the same design, (in carbon fiber though) it must not be pointless.

Well if it was made by Dinan.. guess I made my point.

[Freon]

The factory intake on this car is actually quite good, but extra filter area by adding a secondary filter should aid airflow a bit.

I think that's the gain with any aftermarket intake on the car in general. You're swapping out a square filter for two large cone filters or otherwise, hopefully to the point you end up with a lot more total filter area. The more filter area you have all else being equal, the longer the filter lasts and the lower the pressure loss across the filter at high flow rates.

This is an interesting mod. I doubt it can really hurt as long as you carefully seal your tube into the airbox and carefully clean up all the plastic bits after you drill your hole. If you don't like it there are plenty of people with factory airboxes that will probably sell you one for cheap. The other added bonus is you maintain the "seal" between the front snorkel and the engine bay itself. Few of the popular aftermarket intakes do this, most make a passing attempt at best.

[New2M3]

Looks good gonna make this soon

[cbl117]

Originally Posted by e36addict

Well if it was made by Dinan.. guess I made my point.

Dinan uses carbon fiber for their tubing which is smooth and a bit more heat resistant. This tube has ribs (for the cars pleasure) and the bends must make alot of turbulance. More filter area for sure but I don't think that outweighs the added turbulence. I think DCI is really all you need for a turbo car. Do you honestly think the air temp after the turbos is any cooler?? If you're concerned about air temps after a few runs it sounds like you need to consider intercooler design.

[Indo Rider]

Originally Posted by thetaobear

This is for the 135i N54
Smoothness
What makes this intake system outshine the DCI is smoothness. When I WOT, the power seems smooth throughout the RPM. This was definitely *not always the case* with the DCIs. Most prominent example is after traffic or windy roads, when I WOT with the DCIs, I feel some sluggish/hesitation at higher RPMs. I believe this is because of the inconsistent oxygen that the DCI sucks in during slow traffic, etc. since all the air is coming from inside of your hood with all that hot air mixed in. This is extremely prominent during traffic driving. With the Mr5 intake, even through traffic, my car pulls nicely; DCIs feel sluggish at times. Just for reference, the weather here is 60-70 degrees F and 50-70% humidiy.

This made be laugh. Gotta get that oxygen yo!