[E90 335xi]

Hi All,

This is one of my first posts here... I'm looking for some advice from you regarding tried-tested-and-true mods.

I have an E90 335xi and so far have the BMS JB4, BMS Intake, Sonic Tuning coilovers, and Pilot Super Sport tires (not sure if that counts as a mod, but they're way better than the runcraps). I feel the car is very well balanced in terms of acceleration/handling/braking, but of course, the power bug is hungry and I'm thinking maybe a few more bolt-ons will satisfy that craving.

So... what are the next few best bang-for-buck power mods?

I don't intend to race the car, it's a daily driver in our crappy Canadian weather so she sees anything between snowstorms with 0 degree weather to occasional nice summer days of 85 degrees.

My research is inclining me to go towards:
-VRSF catless downpipe ($290)
-VRSF chargepipe ($195)

What do you guys think? VRSF claims 25-30hp gains from the catless DP with a tune (not sure if they mean whp or crank gains). Another benefit is faster turbo spool? Also, from reading up on the chargepipe, it's more of a durability mod to accomodate higher boost levels, and it won't really increase performance... right?

I run my JB4 on Map 5 and fill up with Shell 91 or Ultramar 91 (ethanol-free) here in Canada. I can get 94 but it has ethanol in it so I kind of stay away from it. My boost is generally 13psi and occasionally creeps to 16-17psi (based on the guage hijack; I haven't datalogged yet).

I also understand an intercooler upgrade will help keep intake air temperatures lower and more consistently so. Given the cost however, I'm not sure I need that considering our climate. July and August, we occasionally see 90 degrees or more, and it's pretty humid, but summer temperatures are usually up to 85 at most.

I know methanol is also an option, although I know very little about it. Is it a good bang/buck for me at this point?

Thanks in advance for your replies!

[4lss]

My first two mods were JB4 and BMS intake. Right after that I went with VRSF cp and dp and ff wires. I enjoyed driving even more after the dp install. I would go that route.

Can you post a pic of your car? I'm thinking about getting the same coilover setup, do you have the newest version?

[NoImDirtyDan]

Your DP install is going to be costly unless you do it yourself. i've heard (read) DP install on an xi is a PITA. But catless DP is def the next mod I would do. Worth every penny. You should have ordered the chargepipe with the JB4 so I would order that ASAP you never know when the stock one might crack under those boost levels. Intercooler helps in the higher RPM's from what I know and read it made a difference on my car. I believe that covers FBO. I cannot comment on meth since i've never used it I feel like FBO is enough power since youre not looking to track the car and you have higher octane fuel. (Im stuck with Californias 91 octane). If you did want more power I would jump on a turbo upgrade. Im thinking about it mostly because it holds boost farther in the RPM range.

[E90 335xi]

Thanks guys. My mechanic said it should take 4-5 hours to install the DP & CP.

How strong is the gas smell when running catless DP? Also, I've watched countless Youtube vids on catless DPs and they all sound raspy to me. Part of the problem is that 99% of the vids are with a camera left just by the exhaust tips of a parked car. In-car sound and takeoffs/drive-by-acceleration would give a much better idea of sound.

djfellipe: here's a few pics. I just got these in March 2015. The fronts can go a bit lower, the rear way lower, but I like it the way it sits. So grateful to have gotten rid of that god awful reverse-rake that the XIs have stock.

[neverdone]

How is the ride on those coilovers? I want to drop my xDrive, at max, the same as you, I don't want to slam this car, but I need a comfortable ride.

[NoImDirtyDan]

Personally I'm running catless DP + stock mufflers and it sounds like a beast quiet when cruising and loud when smashing. Gas smell is strong but it depends on the weather. Hot/humid you're gonna get a strong smell. Cold windy you won't smell it in the cabin windows down. I noticed with the FMIC (7" VRSF) the smell wasn't as strong especially when idling. Cold start is loud and smelly which is expected but once it warms up it idles with a nice low rumble and the smell isn't too strong.

Here's a quick drive by of my car sorry it was taken on an iPad

[4lss]

Your car looks really good BTW!

CP shouldn't take more than 30 minutes, DP took me 4.5hrs the first time, 2.5hrs the second time just a week ago on jack stands.

In my case, you can only smell the gas if you are right behind the car, it sounds really good with the stock exhaust. It's loud at cold start for 10 seconds after that it tones down a bit.

[jonluc88]

Hey man! Great looking car you got there! I am FBO with secondary cat and I cant smell anything from the exhaust. But the sound of the BMW PE combined with DP is AMAZINGG!!!!

I never regretted ditching my OEM DP.

Happy modding!

[sw1183]

Nice Looking ride man, I have the exact same Msport (n55) and am FBO.

With your current setup and situation in mind and with all the mods available on mine, my personal opinion would be:

1) Charge Pipe - suck it up, you have to do it otherwise it will break under boost loads like mine did and you'll be stuck on the backroads waiting for a tow. (btw, mine broke only with a jb4 mod)

2)JB4 FlexFuel wires. (assuming you can get e85 in Canada) Kinda a pain on first install, but adding 5-8 gals of e85 turns this car into a BEAST. It is a cheap mod that will get you instant power increases on map 5.

3) Downpipe. Choose your vendor - VRSF builds quality products at reasonable prices and thats why I choose them (On our xi's, there are two cats, I have had this installed for a year and there was no smell at all - startups are a lot louder however)

4) Alpina TCU Flash - the downshifting rev matching with the downpipes make this car gurgle and sound soo sweet. The TCU Flash shifts really increases our 0-60 time (with 25-35F temps I put down a best 3.48 0-60. I also have Continental DWS tires that helped)

5) FMIC - This really is a necessary component, but, you said you're not tracking this car so I would put it last on a numbered list. It really has helped decrease my IAT temps as I usually do a lot of pulls when I drive (15-30F degrees) I noticed at around 4-4500k a stronger pull (VRSF) as well. Also, I recommend a CP before this, as the connection on BMWs plastic could crack when you tighten it, you really want a metal cp for a strong connection.

Again, these are just my opinions, but I have the exact same setup assuming your an N55 xi also. Hope this helps man!

[sw1183]

Originally Posted by neverdone

How is the ride on those coilovers? I want to drop my xDrive, at max, the same as you, I don't want to slam this car, but I need a comfortable ride.

I have H&R Springs with stock suspension. I don't recommend this setup without upgrading other components as it can be a pretty rough ride at times.

[E90 335xi]

Thanks guys. I have an appointment next week at a local exhaust shop to do the PE mod to my factory exhaust, so maybe I'll wait and see how I like the sound of it before going the DP route. I did the math and it would cost me about $800 Canadian bucks by the time I have the DP intalled on my car. Hmmm... don't know if that's really worth 25whp for a daily driver.

Originally Posted by neverdone

How is the ride on those coilovers? I want to drop my xDrive, at max, the same as you, I don't want to slam this car, but I need a comfortable ride.

It's good. It's surprisingly comfortable. Damper setting recommendations from Sonic Tuning were 5F/8R for daily driving comfort, and 11F/14R for agressive driving/racing. I started out with 5/8 but moved up to 11/14. Both myself and my mechanic found the damping at 11/14 to be better matched to the spring rate. This is a daily driver that I don't race so I am very happy with the comfort level. It's still just around 32 degrees around here so I haven't had a chance to really push the car much but there's less body roll and the steering feels quite connected.

My only gripe with these coilovers is that the fronts make a bit of a harsh hollow sound when going over a significant bump that requires very fast shock compression. Such as a raised manhole cover. Only makes this sound in the front. I had everything looked at to make sure it's tight. I was told it's normal since it's a mid-pack quality coilover. The crappy eBay ones would sound like that all the time, whereas the more expensive (read: 2X the cost) ones would sound normal (like stock) at all times. So, you get what you pay for, but overall I'm quite happy with them anyway and wouldn't have paid twice as much of KWs.

[E90 335xi]

Forgot to mention, thanks for the suggestions on the CP. I was reading elsewhere as well that it's a must. I didn't know. Will order it now.

Also I didn't think E85 was an option but I just found the 1 and only 1 gas station in my town that sells E85.

Can someone tell me more about E85? What else do I need to buy besides the $25 flex fuel wires for the JB4?

[sw1183]

Originally Posted by E90 335xi

Forgot to mention, thanks for the suggestions on the CP. I was reading elsewhere as well that it's a must. I didn't know. Will order it now.

Also I didn't think E85 was an option but I just found the 1 and only 1 gas station in my town that sells E85.

Can someone tell me more about E85? What else do I need to buy besides the $25 flex fuel wires for the JB4?

Read the DIY from BMS on the install - reaching behind the engine not knowing what I was looking for was difficult at first for me. Other than that the install was as simple as the jb4 with only 1 harness to connect.

There are tons of forum post saying if you run more than 8 gallons of e85 you need to make sure you don't over work your fuel pump and they recommend a Whalboro pump at that point. I dont disagree but Ive personally had no issues.

Ive been running 7.5 - 8.5 gallons of e85 / 6 Gallons of 93 octane for full fillups for 18 months with no issues (even before DP & FMIC install). I send logs often on n54tech dot com for review and have increased my max boost to 18.5 with good trims and no issues.

Every engine is different but Ive had no issues. In my opinion I would start with 5 gallons as a safe bet, log, then post on a forum here or elsewhere if you dont know how to read logs. Anyone agree / disagree with this amount?

Regardless, e85 made a huge difference in power in my vehicle -I was shocked and for bang for the buck as you mentioned earlier - is the cheapest and quickest power gains Ive experienced.

[E90 335xi]

Originally Posted by sw1183

Read the DIY from BMS on the install - reaching behind the engine not knowing what I was looking for was difficult at first for me. Other than that the install was as simple as the jb4 with only 1 harness to connect.

There are tons of forum post saying if you run more than 8 gallons of e85 you need to make sure you don't over work your fuel pump and they recommend a Whalboro pump at that point. I dont disagree but Ive personally had no issues.

Ive been running 7.5 - 8.5 gallons of e85 / 6 Gallons of 93 octane for full fillups for 18 months with no issues (even before DP & FMIC install). I send logs often on n54tech dot com for review and have increased my max boost to 18.5 with good trims and no issues.

Every engine is different but Ive had no issues. In my opinion I would start with 5 gallons as a safe bet, log, then post on a forum here or elsewhere if you dont know how to read logs. Anyone agree / disagree with this amount?

Regardless, e85 made a huge difference in power in my vehicle -I was shocked and for bang for the buck as you mentioned earlier - is the cheapest and quickest power gains Ive experienced.

Thanks for all the advice man! BTW your car looks sick too.

I just spent my lunch hour reading up on E85. It seems lot of guys like to do a 60 / 40 mix of pump_91+ / E85. And that all I need is the flex fuel wires which are dirt cheap. Definitely going this route.

It just so happens that the only gas station in my area that has E85 is right on my way to work... it was meant to be!

I read up on logging too, so now that I know how to do that, I'll get the wires, do some logs and post them up to see what BMS says.