335i to 135i - which mods are direct fit?

[orionredwing]

Hi everyone,

I currently own an 07 E90 335i, and am shopping for an 08 135i Coupe. Was wondering if anyone knows which of the following mods on my 335i can be direct fitted onto the 135i?

- Wavetrac LSD (I don't have a welded differential in my 335i, is the 135i welded?)
- Coilovers (KW v3 w/ Swift Springs)
- AR Downpipes
- AMS Intercooler
- M3 suspension bits
- Wheels (M6 reps, guessing not a direct fit, but I'll also try searching wheels subforum)

After a LONG list of repairs, you'd think I'd want to stay away from another N54 (seriously, my spreadsheet looks ridiculous). But as you guys know, this engine's a blast. I figured since I already know all the problems in the N54 (even posting a DIY or two), there'll be a very short learning curve on the 135i. Plus it helps to go in mentally prepared and with a repair budget allocated aside

One good thing about buying used is that I will be able to keep both cars Thanks for your help!

[ErvGotti]

1. The LSD is welded, but both the 07 335i and 08 135i 6MT should both have the large differential. So you'll have to swap the whole assembly. Definitely verify this before attempting the swap.

2. KW's should fit

3. Dp's should fit

4. Intercooler should fit with a bit of trimming.

5. Most M3 pieces should also fit.

6. Wheels more than likely will not fit, the 135i has some of the shittiest off sets for wheels.

[135Pats]

+1 on the above, and id be shocked if the m6 reps fit....our offsets are abysmal, sooo few wheels offer good fitment.

[ParkNuts]

Won't the KW's have different spring rates for a different chassis?

[orionredwing]

Thanks for the response guys. I picked up a used 08 135i 6MT today and will be looking to port my 335i mods over.

[jsmonet]

everything but the wheels and diff are a pretty sure fit.

[Cozy]

You virtually have a 335i with a smaller body so most mechanical parts swap over. With a smaller body comes small bumper so that may need trimming for FMIC as erv says, wheels will almost definitely not fit, ET45 is pushing it on this car .

[uberschnell]

LOL, I traded my 07 Tiag 335 for an 08 135

I think you'll like the trade. And BTW, my 08 135 has had far fewer issues then my 07. Seems they got a lot of thing sorted out.

This is what I learned from my swap:

- LSD swap, auto to auto, internals can be swapped.
- All the suspension pieces can be swapped over. Swapped over my AST's (same springs) and m3 bits including front sway
- Except for the M3 strut bar. Need to get a modified version from HP for that
- Hold off on the rear sway, car does not need it as much as the 335 (but do the subframe bushings for sure)
- You do need a specific 135i oil cooler upgrade, not as much room
- AMS intercooler fits
- Intakes fit
- Wheels, yeah the ET's suck on the 135
- For track use (not autoX) may want to consider some brake upgrades (like new pistons / seals) Those 335 brakes were awesome.


Get the carbon blasted out and a used n54 will run like a champ. Honestly, I'm really happy with the swap. This car is more fun.

[ChristianReyess]

Originally Posted by MteK

Get the carbon blasted out and a used n54 will run like a champ. Honestly, I'm really happy with the swap. This car is more fun.

????? carbon blasted out? where would one go for that? and really it makes that much of a dif?

[splitsecond]

Originally Posted by ChristianReyess

????? carbon blasted out? where would one go for that? and really it makes that much of a dif?

It may be placebo, but I felt a huge difference. I went to VS Motorsports in Chicago, but you might have a place in your area too. Where are you?

[sparkyblue]

Originally Posted by orionredwing

Hi everyone,

I currently own an 07 E90 335i, and am shopping for an 08 135i Coupe. Was wondering if anyone knows which of the following mods on my 335i can be direct fitted onto the 135i?

- Wavetrac LSD (I don't have a welded differential in my 335i, is the 135i welded?)
- Coilovers (KW v3 w/ Swift Springs)
- AR Downpipes
- AMS Intercooler
- M3 suspension bits
- Wheels (M6 reps, guessing not a direct fit, but I'll also try searching wheels subforum)

After a LONG list of repairs, you'd think I'd want to stay away from another N54 (seriously, my spreadsheet looks ridiculous). But as you guys know, this engine's a blast. I figured since I already know all the problems in the N54 (even posting a DIY or two), there'll be a very short learning curve on the 135i. Plus it helps to go in mentally prepared and with a repair budget allocated aside

One good thing about buying used is that I will be able to keep both cars Thanks for your help!

Originally Posted by MteK

LOL, I traded my 07 Tiag 335 for an 08 135

I think you'll like the trade. And BTW, my 08 135 has had far fewer issues then my 07. Seems they got a lot of thing sorted out.

This is what I learned from my swap:

- LSD swap, auto to auto, internals can be swapped.
- All the suspension pieces can be swapped over. Swapped over my AST's (same springs) and m3 bits including front sway
- Except for the M3 strut bar. Need to get a modified version from HP for that
- Hold off on the rear sway, car does not need it as much as the 335 (but do the subframe bushings for sure)
- You do need a specific 135i oil cooler upgrade, not as much room
- AMS intercooler fits
- Intakes fit
- Wheels, yeah the ET's suck on the 135
- For track use (not autoX) may want to consider some brake upgrades (like new pistons / seals) Those 335 brakes were awesome.


Get the carbon blasted out and a used n54 will run like a champ. Honestly, I'm really happy with the swap. This car is more fun.

Since you two both came from a 335i and moved onto a 135i. What are your opinions of the two?

I'm actually looking to do the opposite, I'd like to get out of my 135i and move into a 335i Sedan.

Does the car feel any bigger around town? Hows the handling? Braking?

[Cozy]

I'm another 335i - 135i member. I swapped as the 135i is a much better drivers car where as the 335i was great at being a cruiser, somewhere between 1er & 5er. I find that the 135i turns in shaper, stops quicker, accelerates a little faster and handles better stock for stock but what it lacks in compared to the 335i is a lower quality interior (marginally I guess), it has mega hard suspension with the RFTs, doesn't look as pretty or have the cool twin exit pipes, the OE exhaust system isn't at throaty or as sporty sounding (the 135i and golf-tee mod does less) and finally the 3-series badge comes with more prestige.

There is a bonus to owning an E82/E88 now though, it still has 1 full production year left where as the E90 has been replaced for some time and the E92/93 are in their last days priors to the 4-series. Based on that the value of the e82 will hold up for a little while yet.

My opinion overall was that to gain the same level of performance as a stock 135i, the 335i needed suspension stiffening and brakes but both need RFTs gone ASAP.

[splitsecond]

If you decide not to install the M3 bits, I might buy them from you.

[ChristianReyess]

Originally Posted by splitsecond

It may be placebo, but I felt a huge difference. I went to VS Motorsports in Chicago, but you might have a place in your area too. Where are you?

South orange county in california. Nad maybe I've read others stating they felt it helped too, so I am a bit interested.

[splitsecond]

LTMW is the place to go in SoCal. Their prices are pretty reasonable too.

[ken1137]

Originally Posted by sparkyblue

Since you two both came from a 335i and moved onto a 135i. What are your opinions of the two?

I'm actually looking to do the opposite, I'd like to get out of my 135i and move into a 335i Sedan.

Does the car feel any bigger around town? Hows the handling? Braking?

Bored tonight and came across your question. I am a 335i owner and former 135i owner. I miss it very much! Yes, you feel like you are driving a sedan. The handling is meh (not a 135i), braking similar, but the ride is smoother. I have Sport suspension (w/run craps), will be adding BMW performance suspension soon, and PSS' later. It will feel big and burly so I would recommend a tune. I am very pleased with GIAC Stage II. Very smooth and a shit load of boost at the higher end. I should've tried GIAC on my 135i. GL