///M1.5 Build Thread

amg6975

Corporal
Oct 27, 2019
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2012 135, 2005 ZHP, 2009 fJCW
Totally different but both frames will bolt up to the chassis with no modification.
This is a bit of a hyperbole. The only difference is how the motor mount attaches. The N55/54 subframe has the two bolts for the newer style "tall" motor mounts, and the S65 subframe has the single bolt style mount that RWD bimmers have had since the E30. I would definitely suspect the S65 could be made to work with the N55/54. Everything else is exactly the same, suspension mounts, steering rack mount, etc.
 

syn909

Specialist
Jun 27, 2018
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'07 335i
@amg6975 That's a good point I have to agree with you thats exactly what I suspected and it should not be too hard to fabricate motor mount adapters from S65 subframe to 335i mounting position
 

amg6975

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Oct 27, 2019
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2012 135, 2005 ZHP, 2009 fJCW
@amg6975 That's a good point I have to agree with you thats exactly what I suspected and it should not be too hard to fabricate motor mount adapters from S65 subframe to 335i mounting position

Yeah, maybe. Doubt it would be worth the effort to be honest. The suspension components already bolt to where the cross members in the subframe are so I don't imagine they're moving much.
 

amg6975

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Oct 27, 2019
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Your forgetting about the sump position and the position of the mounts, I dont think it would be worth the effort something a custom brace could not fix.
No, I'm not. there are exactly two major physical differences in the subframes. The type of the motor mount and the rear "wings" on the V8 subframe, which we know doesn't matter. Other than that they are exactly the same size. The only other difference I find are the mounts for the brace on the V8 subframe.

I have absolutely no doubt if the engine mounts were addressed you could install the V8 subframe in an N55/54 car.

IMG_4565.jpg
 

amg6975

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Oct 27, 2019
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2012 135, 2005 ZHP, 2009 fJCW
No you could not, the down pipes will hit the s65 subframe as we already tried.

You could possibly make the n54 subframe work with a v8 but not the v8 with the n54.

Look at the passenger corner closely just behind the engine mount.
Good point. I'd bet a custom exhaust could be made but I like I said previously, I can't see it being worth it.

Back to M1.5 talk please.
 

derekgates

Lieutenant
Feb 23, 2018
727
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derekgates.us
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2011 335is
Good point. I'd bet a custom exhaust could be made but I like I said previously, I can't see it being worth it.

Back to M1.5 talk please.

Yes please, how is it coming!

(I like to hear about both setups and I lust after having a V8/M3... but I want to see more of this swap!)
 

amg6975

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Oct 27, 2019
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2012 135, 2005 ZHP, 2009 fJCW
Yes please, how is it coming!

(I like to hear about both setups and I lust after having a V8/M3... but I want to see more of this swap!)

It's coming. I've been updating the original couple posts so that when I'm done it will be easy to reference rather than scrolling through a massive thread to find updates. I'm in trenches of wiring right now, slow and tedious!

My birthday is the 12th so my goal is to fire the engine in the M1.5 by my birthday... long way to go but I think it's possible if it stays warm enough to spend a couple hours a night in the garage!
 
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amg6975

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Oct 27, 2019
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2012 135, 2005 ZHP, 2009 fJCW
@martymil do you know what you did with the aux vacuum pump and vacuum sensor? I think I want to eliminate this as it's supposedly just for when the car is first started but I'm not sure if it's even possible to delete.
 

martymil

Colonel
Sep 6, 2017
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I reused it and running it same way the m3 did everything is just the same and fits. I used a rubber hose clamp to mount it under the guard.

You need it all the time as it supply's vacuum to the brakes in low vacuum conditions unless you have a full racebox pedal setup then you won't need it.

These engines don't produce enough vacuum especially when your punishing it through the curves
 

amg6975

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Oct 27, 2019
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2012 135, 2005 ZHP, 2009 fJCW
I reused it and running it same way the m3 did everything is just the same and fits. I used a rubber hose clamp to mount it under the guard.

You need it all the time as it supply's vacuum to the brakes in low vacuum conditions unless you have a full racebox pedal setup then you won't need it.

These engines don't produce enough vacuum especially when your punishing it through the curves
That's what I figured. I don't think it's going to fit behind my 135 fender so I may relocate it to the battery compartment or something. Thanks!
 

amg6975

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Oct 27, 2019
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2012 135, 2005 ZHP, 2009 fJCW
Big bump. Been hard at work on wiring now that the weather is decent. Posts updated.
 

amg6975

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Oct 27, 2019
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2012 135, 2005 ZHP, 2009 fJCW
Updated the Chassis and Electrical sections, engine bay studs, fuel/brake lines, rear subframe, gas tank.
 

amg6975

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Oct 27, 2019
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2012 135, 2005 ZHP, 2009 fJCW
Hey @martymil what did you do about DCT and engine oil coolers? The 135 oil cooler is too “tall” for the M3 DCT lines to fit correctly. Also doesn’t look like the M3 engine oil cooler will fit which is a big bummer.