replacing twins- to lower subframe or remove completely

turbo replacement remove subframe completely or lower

  • lower subframe

    Votes: 6 18.2%
  • remove subframe completely

    Votes: 27 81.8%

  • Total voters
    33

foe516

Specialist
Nov 5, 2016
79
15
0
11730
so next week i am going to a friends shop to do turbos, oil pan gasket, pulleys, motor mounts, csf radiator. we will be doing on a lift. he thinks we should remove subframe completely. i have read a lot of you guys just drop it. looking for your opinions.
 

markyb0

Corporal
Jun 17, 2017
106
20
0
Hampton, VA
Ride
2009 335i ST
Id remove it completely. I took off my front turbo once to look at something without taking the subframe out and it just made it 100x harder. Remove it and everything will be out of your way and much easier to work on. Pretty sure you have too drop the subframe anyway to do the oil pan gasket.
 

N54QC

Corporal
Aug 17, 2017
127
67
0
Ride
07 E90 335i
I just lowered mine to do the turbos and pan gasket. Did it in a storage unit on jacks so removing it was out of the question.
 

Milan

Sergeant
Dec 24, 2016
389
219
0
jebi se
Ride
your mom
The extra time it takes to remove the subframe is easily offset by the time savings of installing the new turbos without the subframe in the way. Maybe with a design like MMP it wouldn't be too bad
 

Torgus

Major
Nov 6, 2016
1,773
1,225
0
Boston
Ride
ACF 6466 E92 + METH
I lowered it when I did my single install. It honestly does not take much time to do. I can't imagine doing the install of a single or stock frame without doing so. I mean I am sure it could be done but is it worth the hassle?
 

buster84

Corporal
Mar 24, 2018
240
91
0
Ride
335 bmw xdrive
If the shop is doing it have them take it off to make it easier and faster for them. If your doing it yourself its upto you to decided which you prefer.

On my xi I lowered my subframe and replaced my turbos (went from gc 1.0 to 2.0) so my experience might be a tad different since I could remove it easier by splitting the manifold; however, I had to install the manifold to the turbo before reinstalling so it was reinstalled no different than a stock turbo. I never removed the front axle, or the waterpump/thermostat. If you have the time and small hands it's very doable.

The way I look at it is this. If you want to remove the least amount of parts to save you self the trouble of losing bolts/breaking anything or not knowing where things go back then I'd suggest dropping the subframe and then if you hate the smaller working area you will always have the option to fully drop it. Just make sure you get good torque wrenches that range from 5nm to 100nm to retorque all the bolts back to OEM specs.
 

langsbr

Captain
Apr 5, 2017
1,176
673
0
Ride
07 335i 6MT e90
I voted to remove it completely. It's not that many bolts, only takes a few minutes to do, and give you unfettered access to everything. Why make life difficult by leaving it in place?
 
  • Agree
Reactions: Torgus

veer90

Captain
Nov 16, 2016
1,000
762
25
West Nyack, NY
Ride
e90 335i 6MT
I lowered it when I did my single install. It honestly does not take much time to do. I can't imagine doing the install of a single or stock frame without doing so. I mean I am sure it could be done but is it worth the hassle?

I did my single turbo install on jack stands in a parking space with the subframe in. Sucked donkey dick but is definitely doable.

If you have a lift and are also doing OPG, etc, just remove the subframe so you don't hate yourself lol
 

fmorelli

Major General
Staff member
Aug 11, 2017
3,166
2,881
0
54
Virginia
www.morelliguitars.com
Ride
E89 Z4 35i, F10 535d
... or you can do it like my buddy @Asbjorn 's folks in China ... they don't fool around.

Filippo

(from Asbjørn's build thread)
mmexport1526281329198.jpg
 

chadillac2000

Corporal
Oct 26, 2017
233
253
0
NC
Ride
2008 BMW 135i
I'd suggest not being in a hurry with an install of this magnitude and just remove it. You'll spend more time working around it then you'll have invested in just taking it off. Next time I have to go back in for a turbo install, I'll probably just pull the engine/trans out the front and assemble everything on a stand.
 
  • Agree
Reactions: Jeffman and Torgus

buster84

Corporal
Mar 24, 2018
240
91
0
Ride
335 bmw xdrive
I'd suggest not being in a hurry with an install of this magnitude and just remove it. You'll spend more time working around it then you'll have invested in just taking it off. Next time I have to go back in for a turbo install, I'll probably just pull the engine/trans out the front and assemble everything on a stand.

Not true for everyone. If your smaller with smaller hands you have more room than someone that's alot bigger overall. Space is relative to your size so removing the subframe is just another way to make it easier for certain people. It just depends on your comfort level. The longest part of the turbo install is figuring out where what goes where and what torque you need to apply to what bolt and what sequences are needing for reinstalling it without wasting time removing something ecusse you forgot something. I had this problem with my right engine mount. Installed everything and I forgot about the engine mount dumb moment but it does happen
 

chadillac2000

Corporal
Oct 26, 2017
233
253
0
NC
Ride
2008 BMW 135i
Not true for everyone. If your smaller with smaller hands you have more room than someone that's alot bigger overall. Space is relative to your size so removing the subframe is just another way to make it easier for certain people. It just depends on your comfort level. The longest part of the turbo install is figuring out where what goes where and what torque you need to apply to what bolt and what sequences are needing for reinstalling it without wasting time removing something ecusse you forgot something. I had this problem with my right engine mount. Installed everything and I forgot about the engine mount dumb moment but it does happen

More power to you my friend. I'm 5 foot 10 inches, 150 pounds so not big by any stretch of the imagination. What's another hour of labor when you're doing all that work yourself though? It doesn't take any specialty tools or know-how, and doesn't mess with any alignment settings, yet frees up all the room in the world. It was worth it in my eyes just for the ease of reinstalling the water pump and all hoses. Not to mention the oil pan gasket, which should probably be replaced while you're in there.

This is with a large DSLR camera and my head fully poked up in the engine bay. Look at all that room!

ypLJTn2.jpg
 

buster84

Corporal
Mar 24, 2018
240
91
0
Ride
335 bmw xdrive
More power to you my friend. I'm 5 foot 10 inches, 150 pounds so not big by any stretch of the imagination. What's another hour of labor when you're doing all that work yourself though? It doesn't take any specialty tools or know-how, and doesn't mess with any alignment settings, yet frees up all the room in the world. It was worth it in my eyes just for the ease of reinstalling the water pump and all hoses. Not to mention the oil pan gasket, which should probably be replaced while you're in there.

This is with a large DSLR camera and my head fully poked up in the engine bay. Look at all that room!

View attachment 13316

I'm not arguing against it I'm just saying that having more room doesnt gaurntee a faster repair especially if your new and by yourself.

I did it on my x-drive and left on alot of stuff on the car and still finished the install in a timely manner. It was fairly quick and the longest part for me that took all day was relifting the subframe while alligning it all by myself. I had go get crafty and out together some wood and jacked it up that way and got it all together.

To each there owns, but it's always good to hear from people (like you) who have actually done the swap and there methods and car model (x-drive or rwd).

I didnt take many photos but here is one that shows how much I left on when doing the swap. I wished I snapped a photo of the amount of free space i had but I apparently didnt. I'm 5'10 155lbs and felt like I had plenty of room.

Here's some photos of the turbos installed and everything I left on.

20180323_211312.jpg
20180323_211229.jpg
20180510_185428.jpg
 

silverstreak18

Corporal
Jan 3, 2018
126
65
0
Charlotte, NC
Ride
2016 M3
I'm not arguing against it I'm just saying that having more room doesnt gaurntee a faster repair especially if your new and by yourself.

I did it on my x-drive and left on alot of stuff on the car and still finished the install in a timely manner. It was fairly quick and the longest part for me that took all day was relifting the subframe while alligning it all by myself. I had go get crafty and out together some wood and jacked it up that way and got it all together.

To each there owns, but it's always good to hear from people (like you) who have actually done the swap and there methods and car model (x-drive or rwd).

I didnt take many photos but here is one that shows how much I left on when doing the swap. I wished I snapped a photo of the amount of free space i had but I apparently didnt. I'm 5'10 155lbs and felt like I had plenty of room.

Here's some photos of the turbos installed and everything I left on.

View attachment 13317 View attachment 13318 View attachment 13319

You have a decent amount of room when you lower the subframe, I still find it easier to swing it out of the way. It takes maybe 10 more minutes to do so. Judging from the corrosion on those control arm bolts though I'd guess you're up north, so I probably wouldn't want to take apart anything I didn't absolutely have to either.
 

buster84

Corporal
Mar 24, 2018
240
91
0
Ride
335 bmw xdrive
You have a decent amount of room when you lower the subframe, I still find it easier to swing it out of the way. It takes maybe 10 more minutes to do so. Judging from the corrosion on those control arm bolts though I'd guess you're up north, so I probably wouldn't want to take apart anything I didn't absolutely have to either.

I'm actually in FL, but I purchased the car recently from someone who lived where it showed alot and had salt all over the roads.