[hutch423]

I am in the beginning stages of modifying my 435i and I think there may be a tune from the previous owner in it. I am unsure if there even is one but my question is if I have to check or remove it before I tune it myself? Also any recommendations for tuning brands? I love this car and I want to do everything right.

[RVA_N55_Fan]

I enjoy my 435i MT. FBO, PS2, Wmi, upgraded pumps, etc. Happy to help w the journey. Pm me as needed.

[johnung]

Originally Posted by hutch423

I am in the beginning stages of modifying my 435i and I think there may be a tune from the previous owner in it. I am unsure if there even is one but my question is if I have to check or remove it before I tune it myself? Also any recommendations for tuning brands? I love this car and I want to do everything right.

Great car! I have the same N55 EWG engine in my 335i XDrive. I’ve been using a Bootmod3 tune for years. When you install Bootmod3, which only takes about 15 minutes from your laptop, the first thing that it does is to save whatever tune is running on your car so that you can always reinstall it and be back where you began.

These engines have a poorly designed plastic charge pipe with a 90 degree bend on the end where it likes to crack right after even the mildest tune is installed. See photo. So best to replace it with a high quality aluminum charge pipe that doesn’t leak before you install a new tune. See link. Avoid cheap CPs because air leaks are expensive to troubleshoot and repair.

This FTP Charge Pipe is high quality, reasonably priced and includes the o-rings that should be replaced.
https://www.kiesmotorsports.com/prod...3&_ss=r?aff=22

Bootmod3 is a smooth powerful factory like tune. It includes free updates, great tech support and an enthusiastic helpful user community. Later the license can be transferred once to another VIN if you buy a new BMW or sell the license for usually $300-$400 on the used market.

You purchase the Bootmod3 license for $595, Map Pack for $50 and yellow installation cable for $20. That’s all you’ll ever need. The license allows you to install one map (another name for tune) of your choice. Map Pack allows you to change to an unlimited number of maps. I installed a Stage1 map years ago. As I upgraded hardware on my car to handle more power, I just installed other maps like Stage2 and Stage2+. Now I’m running a Stage2+ MultiMap that has FlexFuel so I can just put any percentage of E85 fuel in the tank and the tune with optimize the engine performance. I did all that over years without spending a dime more on tuning above my original investment.

When I first bought my car I tried a cheap $300 tune and it was crap. Bootmod3 is the way to go.

After the charge pipe is upgraded, IMO install the Bootmod3 Stage1 91 Octane map and put 92/93 octane in the tank. This assures that the engine will run smoothly even if you get the occasional weak tank of gas. There’s a free Bootmod3 automatic transmission that you can install at the same time.

Drive Stage1 and really enjoy it. It’s a really nice performance bump. Don’t believe the hype that you’ll read from guys who say that you must go to Stage2. The increase from Stock to Stage1 is much bigger than from Stage1 to Stage2.

After Stage1, every additional horsepower costs more and more in hardware upgrades. Possible future hardware upgrades below.

Stage2 needs upgraded Catted or catless free flow downpipe and upgraded intercooler (FMIC). A high quality Catted downpipe is necessary to pass emissions in many states and it eliminates the nasty gasoline smell of catless downpipes.

Stage2+ needs an upgraded High Pressure Fuel Pump (HPFP)

FlexFuel requires a FlexFuel sensor.

E60-E85 fuel use needs a larger HPFP and an upgraded Low Pressure Fuel Pump (LPFP).

BOOTMOD3 LINK- remember to also purchase the $50 Map Pack and $20 Yellow Installation cable. The Kies WiFi adapter works well later if you get into collecting engine logs and running the Bootmod3 app on your phone.

https://www.kiesmotorsports.com/prod...c&_ss=r?aff=22

BOOTMOD3 INSTALLATION VIDEO
https://youtu.be/PsNfSHCH7DI

Hope this helps!

[hutch423]

Wow I couldn’t have asked for a better answer. Very much appreciated. The previous owner installed a vrsf charge pipe on it already thankfully. So that gives me a head start. Next I’m just thinking moderately simple upgrades like a BOV and a intake. After reading this probably an upgraded exhaust. Thank you once again.

[johnung]

Originally Posted by hutch423

Wow I couldn’t have asked for a better answer. Very much appreciated. The previous owner installed a vrsf charge pipe on it already thankfully. So that gives me a head start. Next I’m just thinking moderately simple upgrades like a BOV and a intake. After reading this probably an upgraded exhaust. Thank you once again.

Great that you already have an upgraded charge pipe. The fact that you listed interest in those three mods, I assume that better sound is a priority. I forgot to mention that Bootmod3 has an exhaust dashboard that allows you to custom tune the exhaust sounds to your liking.

Are you doing installations yourself or do you have a good local BMW mechanic? BimmerShops website can be a way to find one. Where are you located in NY? A couple of my buddies have recommended mechanics in NYC and across the river in NJ.

The three mods that you listed have different types of sound and different levels of installation difficulty.

INTAKE
An Intake is definitely a do-it-yourself installation. However there are pitfalls in properly choosing an Intake. There is a lot of misinformation to read about Intakes.

An Intake is NOT a Full Bolt On (FBO) hardware requirement needed to install a Stage2 engine tune. Only a free flow Catted or Catless downpipe (to prevent backpressure damage to the turbo) and an upgraded FMIC (to prevent overheating intake air) are needed.

POSSIBLE BENEFITS OF AN INTAKE:
1) Small, but noticeable, bump (<5%) in engine performance.
2) Added sound from under the hood from hearing some of the turbo spool sound.

CHOOSING THE WRONG INTAKE can actually be a detriment to engine performance, and cause engine error codes. The engine’s Mass Air Flow sensor (MAF) is located in the intake pipe just after the airfilter. BMW tuned the MAF readings based on the environment in the stock intake tube, it’s shape, size, how much the sensor extends into the airflow, etc. Intakes that do a poor job of mimicking that stock sensor environment have problems.

INTAKE PERFORMANCE actually comes from using a free flow air filter, NOT from bigger air holes in the Intake. The bigger air holes are actually allowing the turbo spool sound out. That’s where the enhanced sound originates.

BMW M PERFORMANCE INTAKE
BMW has an aftermarket intake that replaces the bottom of the stock box with one that has an extra hole (trimmed in red) to allow more sound out. See photo.

The performance of the MP Intake can be enhanced by upgrading the stock airfilter to a free flow drop-in airfilter like the aFe Pro Dry. See photo. It’s a washable, reusable air filter that doesn’t have to be oiled and lasts for many years.

MAKE YOUR OWN MP INTAKE
The MP Intake box bottom can be purchased and installed, or it’s easy to modify the bottom of the stock airbox to perform the same function. Simply cut holes in the same location. When installed it’s hidden from view anyway. See photos. Then just swap in an aFe Pro Dry airfilter.

OPEN VS CLOSED INTAKE?
There is so much misinformation and marketing nonsense on what is a very simple concept about the air that enters the airfilter. Colder airflow from the front of the car is better. Air that is heated by being near the engine is worse. Simple!

BMW already ducts air from the front grille directly to the airfilter. It’s important that any added air from an Intake also come from the front of the intake closest to that fresh air source.

The hot engine radiates heat under the hood and heats air around it in the engine bay. Hot air rises. So it’s important that the air filter be shielded from those two directions: from the radiant heat from the direction of the engine and from warm under hood air entering the top of the air filter.

That’s it! Whether an intake is characterized/marketed as being open or closed doesn’t matter. It just needs airflow in from its front side, and heat shielding from direction of the engine and from the top.

AIR FILTER DESIGN/CONSTRUCTION
There is an entire science about air filter size, shape, pleats and filter materials. There are many junk filters out there but can’t tell by looking at them. That’s why I trust a company that specializes in performance air filters like aFe. I’ve had conversations with their technical guys and they know their stuff.

AIRFILTER SURFACE AREA
I have taken measurements on the BMW drop-in filter and the cone filters often used by Intake manufacturers. The cone filter has surface area advantages because of its size/shape and the increased number of pleats.

RECOMMENDATION
IMO the MST Intake has the best combination of performance and sound. MST uses a high quality cone filter that is washable/reusable. The MST shielding design optimizes both the cooler air flow going in and the sound coming out. MST did a great job of design around the MAF sensor so the engine runs smoothly with no error codes. No one has a better airflow design than MST.

Later, Stage2/2+ tunes require an upgraded Turbo Inlet Pipe to maximize the airflow into the turbo housing. The MST Intake and MST Turbo Inlet Pipe provide the smoothest air flow from air filter all the way to the turbo.

I will add separate posts about exhausts and BOVs.

Hope this helps!

LINK TO MST INTAKE
https://www.kiesmotorsports.com/prod...5&_ss=r?aff=22


LINK TO MST INTAKE INSTALLATION
https://youtu.be/-cAgrtaOsz4

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[alrocsmash]

Originally Posted by johnung

.

So, I'm currently running a 2013 335xi with an MHD OTS Stage 2 tune with only the charge pipe and IC replaced. I've been told that the downpipe isn't needed unless you're tracking the car a ton. I've run logs and the pressure seems fine? Was I misinformed?

[johnung]

Originally Posted by alrocsmash

So, I'm currently running a 2013 335xi with an MHD OTS Stage 2 tune with only the charge pipe and IC replaced. I've been told that the downpipe isn't needed unless you're tracking the car a ton. I've run logs and the pressure seems fine? Was I misinformed?

I’m not sure how MHD delineates their Stages vs hardware requirements.

For Bootmod3, by definition Stage1 means everything is stock (except charge pipe on F-N55). Stage2 uses boost levels that with a stock downpipe would cause back pressure against the turbo that could damage it. So a free flow Catted or Catless downpipe is considered a requirement with Bootmod3 Stage2 and above. I’d suggest checking the MHD website for hardware requirements to be certain.

[thejeremyman9]

Originally Posted by hutch423

Wow I couldn’t have asked for a better answer. Very much appreciated. The previous owner installed a vrsf charge pipe on it already thankfully. So that gives me a head start. Next I’m just thinking moderately simple upgrades like a BOV and a intake. After reading this probably an upgraded exhaust. Thank you once again.

This is completely backwards. Intake, BOV, and exhaust are literally the last mods you should do from a tuning/power perspective. IC is first, before doing any tune, then DP is next as it is a requirement for any higher stage tunes. Intake adds primarily just noise. https://f30.bimmerpost.com/forums/sh....php?t=1765289

DV holds up fine stock for stock turbo. Exhaust nets negligible power gains on stock turbo.

John has provided a ton of information, and everything you are asking here has been discussed extensively in the N55 section. https://f30.bimmerpost.com/forums/fo...421&order=desc

[thejeremyman9]

Originally Posted by alrocsmash

So, I'm currently running a 2013 335xi with an MHD OTS Stage 2 tune with only the charge pipe and IC replaced. I've been told that the downpipe isn't needed unless you're tracking the car a ton. I've run logs and the pressure seems fine? Was I misinformed?

MHD stage 2 is IC or DP, not both. Having said that, i wouldnt run any tune without an IC. So you are correct, you can run stage 2 with IC+CP.

Stage 2+ on MHD requires downpipe. You will benefit from a DP at any stage since the OEM one is so restrictive.

[hutch423]

Really appreciate these answers yall. Really in depth information. I’m treating this like scripture. From what I’m hearing I’m not too worried about an intake anymore. If anything just a washable filter. What would the general consensus be on good IC and DP brands? Planning on doing a stage 2 tune so any other recommendations from spark plug gaps to anything preventative I should do.

[Precisionnick]

I ran bootmod3, catless downpipe, and upgraded intercooler. Woke the car up completely ( now I changed to a precision turbo now running Mhd.)

Don’t forget to do the charge pipe first ! Best of luck

[thejeremyman9]

Originally Posted by hutch423

Really appreciate these answers yall. Really in depth information. I’m treating this like scripture. From what I’m hearing I’m not too worried about an intake anymore. If anything just a washable filter. What would the general consensus be on good IC and DP brands? Planning on doing a stage 2 tune so any other recommendations from spark plug gaps to anything preventative I should do.

No offense, but you are basically asking us to do your homework for you. Everything you are asking has already been discussed extensively, especially in the N55 section. https://f30.bimmerpost.com/forums/fo...421&order=desc

For an IC just skip the poorly designed 5'' ones and get a competition size with good fin density.

For DP the main thing that matters is if you are going to pay a premium to get a catted DP that will pass emissions, i.e., AA or fabspeed. If you go catless it doesnt matter, it just needs to fit.

[hutch423]

None taken you’re right thank you for everything.