M3/M4 CS Owners Thread

[mpower79]

suscribedª!

I have pics in my profile

[RugbyBro]

Fresh spray, fresh lip, PPF, and full polish. Next step… adjust the bow in the front bumper / hood region. A notorious issue for LRG cars it seems. Easy fix tho, a couple washers does the trick.

[jmg]

Originally Posted by RugbyBro

Fresh spray, PPF, and full polish. Next step… adjust the bow in the front bumper / hood region. A notorious issue for LRG cars it seems. Easy fix tho, a couple washers does the trick.

I had the same problem. I didn't know it was an LRG thing. What's the contributing factor?

Washers did the trick for me too Btw.

[RugbyBro]

Originally Posted by jmg

I had the same problem. I didn't know it was an LRG thing. What's the contributing factor?

Washers did the trick for me too Btw.

I don't know that it's LRG specific, but I've seen it happen to LRG cars most. I think I know the root cause as I've been under the skin of F8X many times (pic below for reference). As you know, there are a lot of adjustment points between the hood stops, latches, and bumper which play a contributing role in fitment. However, there is one major adjustment point that I don't think people realize... the headlights themselves. These aren't dropped in at a fix position, they have a decent amount of play in them. Once they are set in position, then the bumper is secured to the headlights at the edges of the hood/bumper seam. If you look at a lot of cars that do headlight mods, afterwards they get left with this same awkward gap where the edges droop. so the alignment of the headlights is quite important and can easily effect the front bumper alignment... but unfortunately you won't know if things line up until after it's all reassembled. The other factor (I noticed this on my last car) is that one of the mounting brackets for the headlights to the front assembly is a plastic piece that actually has a decent amount of flex. I would not be surprised if over time, this piece "breaks-in" and settles a little bit lower than originally intended. So the most proper way to fix it would be to just align everything correctly but that's a bit arduous so the simple way is just to use washers as spacers (did this on my old car after painting my headlights, lined up perfectly.)

TLDR: Headlights are a mounting point with lots of alignment play on their own - this is a major contributor to an uneven hood/bumper seam where the edges droop.

[1FZFE]

This thread is easily the best looking M thread in the entire forum. CS needs nothing to look top grade. Well done.

[Chayse]

Originally Posted by jmg

I had the same problem. I didn't know it was an LRG thing. What's the contributing factor?

Washers did the trick for me too Btw.

Where do these washers get installed, may I ask? My SMB has the issue where the center of the hood is slightly lower than the center of the bumper. The edges are fine.

[jmg]

Originally Posted by Chayse

Where do these washers get installed, may I ask? My SMB has the issue where the center of the hood is slightly lower than the center of the bumper. The edges are fine.

There are several support posts on top of the engine bay. I removed the posts, put washers underneath, then reinstalled the posts.

[RugbyBro]

Originally Posted by Chayse

Where do these washers get installed, may I ask? My SMB has the issue where the center of the hood is slightly lower than the center of the bumper. The edges are fine.

I’m doing it this weekend, I’ll make a post about it

[hC1001]

Do you guys ever see steam coming out the front hood at a traffic light? I think its left over water from rain. It doesnt smell like burnt oil or coolant. Just wondering. Thanks.

[jmg]

Originally Posted by hC1001

Do you guys ever see steam coming out the front hood at a traffic light? I think its left over water from rain. It doesnt smell like burnt oil or coolant. Just wondering. Thanks.

I've only seen the heat, but never steam.

[m34m]

Originally Posted by RugbyBro

Fresh spray, fresh lip, PPF, and full polish. Next step… adjust the bow in the front bumper / hood region. A notorious issue for LRG cars it seems. Easy fix tho, a couple washers does the trick.

Gentlemen excuse my ignorance. Respray? What's this about the hood? I've noticed nothing on my SMB. I've posted pics of it earlier in this thread if you don't mind take a look at my car and enlighten me.

[RugbyBro]

Originally Posted by m34m

Gentlemen excuse my ignorance. Respray? What's this about the hood? I've noticed nothing on my SMB. I've posted pics of it earlier in this thread if you don't mind take a look at my car and enlighten me.

Yeah my car had a terrible front respray done prior to my purchase… slipped thru the purchase process for various reasons. The hood issue is separate, it’s where the front bumper bows instead of staying straight with the hood - see my pic and JMG’s thread below. Honestly my hood/bumper seam is probably fine for 95% of people… I’m just part of the 5% that gets annoyed by inconsistencies like that. I also notice the different colors that bumpers have from their car bodies from factory which is not normal for most people lol

https://f80.bimmerpost.com/forums/sh....php?t=1768212

[m34m]

Originally Posted by RugbyBro

Yeah my car had a terrible front respray done prior to my purchase… slipped thru the purchase process for various reasons. The hood issue is separate, it’s where the front bumper bows instead of staying straight with the hood - see JMG’s thread below:

https://f80.bimmerpost.com/forums/sh....php?t=1768212

Ok thanks. Yeah I see the hood issue now. Likely due to CFRP distortion due to temperature deltas. Doesn't bother me at all even if my car had it I wouldn't touch it.

[m34m]

So here's a question I haven't had answered. Does sport+ throttle mode change sound/exhaust in any way? I can't discern any difference from sport.

[RugbyBro]

Originally Posted by m34m

So here's a question I haven't had answered. Does sport+ throttle mode change sound/exhaust in any way? I can't discern any difference from sport.

Regarding sound there is no fundamental tone difference but you’ll hear the turbos spooling due to the quicker throttle sensitivity and there will be a few natural pops which may be hard to hear unless you have burbles disabled. Also, you’ll hear the full cooling system activate at all times (vs situationally in other modes)

[RugbyBro]

As a follow up to my prior post about straightening the hood gap with washers, this is what I mean. You basically use washers as shims between the bumper and headlight / front support. This is the quick and dirty way to fix the gap - the more legit but much more laborious way would be to reposition the headlight. I can also appreciate that this is a very small adjustment, most people probably wouldn’t and shouldn’t care lol

[m34m]

Originally Posted by RugbyBro

Regarding sound there is no fundamental tone difference but you’ll hear the turbos spooling due to the quicker throttle sensitivity and there will be a few natural pops which may be hard to hear unless you have burbles disabled. Also, you’ll hear the full cooling system activate at all times (vs situationally in other modes)

Thanks. Can you clarify what you mean about burbles? My understanding was this car didn't have a burble tune and rather the burbles were natural turbo overrun?

[drb]

First trip in the CS

[RugbyBro]

Originally Posted by m34m

Thanks. Can you clarify what you mean about burbles? My understanding was this car didn't have a burble tune and rather the burbles were natural turbo overrun?

Those crackles and pops in sport and sport+ are mainly programmed burbles. The odd sharp pop or two will be natural overrun but they are usually quite random and inconsistent

[Wanted_M]

Originally Posted by drb

First trip in the CS

Welcome to the FRZN wasteland . Nice CS.

[RugbyBro]

Btw for anyone who wants to run G8X Cup2s on the 763Ms, see below. It’s a 275F 285R setup.

[CanAutM3]

Originally Posted by RugbyBro

Btw for anyone who wants to run G8X Cup2s on the 763Ms, see below. It’s a 275F 285R setup.

Looks nice and meaty. Looking forward to reading about how you like them.