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07-21-2026LAST POST
chocstraw wrote
Is there any consensus about water pump maintenance ? I'm doing an OFHG and alternator soon, debating whether or not to do the water pump while I'm there.

Any thoughts on the metal impeller (Rein) vs plastic ?
I've had a Rein metal impeller pump in my M3 for a few years now with no issue. I've used a few Rein pumps in other cars (190e, E36 M3, 300TD) with no issue.

The OE plastic pump isn't really a concern but a well cast metal one is good insurance on the rare chance a plastic one breaks. I've seen people use the GMB/Graf metal pump but the impeller looks like it would be worse because the fins aren't as well shaped. The Rein pump looks like an exact copy of the OE plastic pump but in cast metal.

The Rein pump is $120 on Rockauto btw :cool!:
chocstraw wrote
Is there any consensus about water pump maintenance ? I'm doing an OFHG and alternator soon, debating whether or not to do the water pump while I'm there.

Any thoughts on the metal impeller (Rein) vs plastic ?
None of the BMW techs I know think the plastic impeller on this car is an issue to worry about nor have they seen them fail. But they also didn’t object to me putting a Graf pump in. If it doesn’t work out I have the FCP warranty.
spammysammich wrote
None of the BMW techs I know think the plastic impeller on this car is an issue to worry about nor have they seen them fail. But they also didn’t object to me putting a Graf pump in. If it doesn’t work out I have the FCP warranty.
if its good enough for the GT4 its good enough for me lmao.
omgzirra_exe wrote
if its good enough for the GT4 its good enough for me lmao.
lol GT4 part use is the best way to make informed decisions on an e9x M :)
first track day in the books at NJMP.... car performed great minus some steering wheel vibration/shuddering during heavy braking (have brand new Girodisc front rotors + Hawk DTC-60s all around, with <500 miles on both. rear rotors have plenty of life). Trying to figure out what could be causing it... (front bushings???). Either way - enjoy the pic!

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Eric335 wrote
first track day in the books at NJMP.... car performed great minus some steering wheel vibration/shuddering during heavy braking (have brand new Girodisc front rotors + Hawk DTC-60s all around, with <500 miles on both. rear rotors have plenty of life). Trying to figure out what could be causing it... (front bushings???). Either way - enjoy the pic!

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Swapping to monoballs in the tension arms seemed to help with that for me. I still get some weird behavior on hard braking in specific corners but solid subframe bushings + front tension arm monoballs seemed to mostly help. For me the rear seems to shift slightly / not turn in a straight line specifically on downhill braking zones (T10 Thunderhill being a main one).
bipp wrote
Swapping to monoballs in the tension arms seemed to help with that for me. I still get some weird behavior on hard braking in specific corners but solid subframe bushings + front tension arm monoballs seemed to mostly help. For me the rear seems to shift slightly / not turn in a straight line specifically on downhill braking zones (T10 Thunderhill being a main one).
Thank you! Where did you get yours / do you have specific recommended products? I was doing some research and thought those might be good place to start.
Eric335 wrote
Thank you! Where did you get yours / do you have specific recommended products? I was doing some research and thought those might be good place to start.
I use the GAS monoballs (new tension arm with pre-fitted monoball - with shop labor in my area the price to get a monoball pressed in was close enough to getting it preassembled lol) and the CMP subframe bushings. https://germanautosolutions.com/gas-store/gas-bmw-e82-1m-e90-m3-monoballs-pre-installed-into-new-control-arms-4/ is the link but seems to be taken off their page - might be worth sending them an email.

The caveat to the CMP bushings is that they correct roll center, which I wanted but is up to you if that is something you want (and want something equivalent in the front). Otherwise, can't go wrong with the Bimmerworld ones.

I also just picked up my car from the shop and one rear camber had gotten to -1.4 and the other was at -1.8 (last aligned in 2024, 6 track days ago). So maybe that led to the rear end instability...
Eric335 wrote
first track day in the books at NJMP.... car performed great minus some steering wheel vibration/shuddering during heavy braking (have brand new Girodisc front rotors + Hawk DTC-60s all around, with <500 miles on both. rear rotors have plenty of life). Trying to figure out what could be causing it... (front bushings???). Either way - enjoy the pic!

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Probably improper bedding of pads

Drive through it a few sessions and it will clear itself up once some repeated heat gets into then system
danvitmon wrote
The OE plastic pump isn't really a concern but a well cast metal one is good insurance on the rare chance a plastic one breaks. I've seen people use the GMB/Graf metal pump but the impeller looks like it would be worse because the fins aren't as well shaped. The Rein pump looks like an exact copy of the OE plastic pump but in cast metal.

The Rein pump is $120 on Rockauto btw :cool!:
I was able to get most of the parts on RockAuto, with the water pump I was more concerned about other things like bearings / seals, etc— I also don't see how metal vs plastic makes a huge difference.

As I'm doing this big service at 137k, I have a whole list of things to do—
- Fuel tank breather
- Injector cleaning
- OFHG
- Water pump, radiator hoses
- T-stat (motorrad 180F vs stock 174, no particular reason but availability)
- Alternator
- Belts
- All pulleys and belt damper / tensioner.
- PS reservoir (why not ? Integrated filter at 137k)
Edit: Also doing PCV, VC, and those front VANOS gaskets too.

I think I'm at under $900 or so with all of this, maybe another $200 for local injector cleaning.

Is there anything I'm forgetting ?

I did GAS monoballs, poly diff, and solid subframe about 9 months ago. Could not recommend this more. No appreciable loss of NVH, massive confidence gain. I bought a second subframe for $200 locally, had these pressed, and swapped everything out, later sold the old subframe for $200
okusa wrote
In case anyone's interested...selling my Trailex trailer

https://www.m3post.com/forums/showthread.php?t=2082602
this is a really old post, but interested in how easy it was to load/unload an e9X onto the Trailex 7541/7551? My HOA is very strict so looking at a trailer that can fit in my garage (which is just a shade under 20') and this seems to be one of the only options. I see you had a winch which I assume helps given the reasonably narrow track of these.

Any other feedback welcome.
e92BMW///M3 wrote
this is a really old post, but interested in how easy it was to load/unload an e9X onto the Trailex 7541/7551? My HOA is very strict so looking at a trailer that can fit in my garage (which is just a shade under 20') and this seems to be one of the only options. I see you had a winch which I assume helps given the reasonably narrow track of these.

Any other feedback welcome.
I had a winch for emergencies only and only used it twice. Loading:unloading is a breeze. For loading I would always poke my head out the window but never for unloading. It’s really not a narrow track. Even with 305/645/18 square and massive front aero there is plenty of room up front and on either side (at least an inch between tire and track lip on either side).
okusa wrote
I had a winch for emergencies only and only used it twice. Loading:unloading is a breeze. For loading I would always poke my head out the window but never for unloading. It’s really not a narrow track. Even with 305/645/18 square and massive front aero there is plenty of room up front and on either side (at least an inch between tire and track lip on either side).
Great to hear. Hoping to rent one for a weekend before pulling the trigger but this gives me a lot of confidence.
e92BMW///M3 wrote
Great to hear. Hoping to rent one for a weekend before pulling the trigger but this gives me a lot of confidence.
Let me know if you end up buying it and it doesn’t come with a winch because I have an unused Trailex manual one you can have (unless you want an electric one).
chocstraw wrote
I was able to get most of the parts on RockAuto, with the water pump I was more concerned about other things like bearings / seals, etc— I also don't see how metal vs plastic makes a huge difference.

As I'm doing this big service at 137k, I have a whole list of things to do—
- Fuel tank breather
- Injector cleaning
- OFHG
- Water pump, radiator hoses
- T-stat (motorrad 180F vs stock 174, no particular reason but availability)
- Alternator
- Belts
- All pulleys and belt damper / tensioner.
- PS reservoir (why not ? Integrated filter at 137k)
Edit: Also doing PCV, VC, and those front VANOS gaskets too.

I think I'm at under $900 or so with all of this, maybe another $200 for local injector cleaning.

Is there anything I'm forgetting ?
you're better off just replacing the injectors, cleaning them will be a waste of time and money.
Had a great time at Putnum last weekend instructing with 10/10ths Motorsports in Indy. It was super hot (ambient was 95 with high humidity) so track was at least 120 or more. All I can say is the poor tires were toast by the end of the weekend as my student and I both shared the car Sat/Sun and I let another buddy get a session in. No track records accomplished, lol, but I still got down to the 1:17's with worn RE71'RS.

Having a problem with my helmet gopro washing out in high sun light, anyone experience this issue too and have a fix for it?

Video of my one of my stints.....


Next up I'll be instructing at Mid Ohio the first weekend of August with the Buckeye Chapter of BMW CCA. Already ordered a new set of V730 as I want to try these in the heat and a new set of front DTC-60's, and water wetter.

Rubin
former 240 s14 wrote
Having a problem with my helmet gopro washing out in high sun light, anyone experience this issue too and have a fix for it?
buy some ND filters for your GoPro, the settings won't be enough to fix that issue.
omgzirra_exe wrote
buy some ND filters for your GoPro, the settings won't be enough to fix that issue.
Good to know, could you elaborate on these ND filters a bit more, a quick Amazon search and it looks like a ton of options, just want to ensure I get the right type?

Rubin
former 240 s14 wrote
Good to know, could you elaborate on these ND filters a bit more, a quick Amazon search and it looks like a ton of options, just want to ensure I get the right type?

Rubin
Definitely aim for a variety, since sunlight intensity and glare will change throughout the day. I usually run an ND4 filter as my “general purpose” setup, but you might want to go with an ND8 depending on conditions. Most ND kits come with a set of 4, 8, 16, and 32, which gives you a good range to work with.

ND (Neutral Density) filters reduce the amount of light entering the camera. This helps cut down on glare and allows your footage to look more natural by letting you use lower shutter speeds and wider apertures, especially important for hitting the 1/120 shutter speed at 60fps for proper motion blur/sense of speed.

Without an ND filter, if you're shooting in direct sunlight, you’ll often be stuck with a super high shutter speed, which can make your footage look choppy or overly sharp. The ND lets you dial in the right f-stop (aperture) without blowing out your highlights.

For GoPro, make sure you get ND filters that are compatible with your specific model (e.g., Hero 11/12/Max). Most kits clip on or replace the lens cover. Look for well-reviewed brands like PolarPro, Freewell, or even Telesin for budget options.

That’s basically my GoPro setup. I just swap ND filters or tweak the aperture depending on the light. It’s definitely not a “set it and forget it” deal, conditions change throughout the day, so you’ll be adjusting as you go.
omgzirra_exe wrote
you're better off just replacing the injectors, cleaning them will be a waste of time and money.
was about to say this. Injectors are $400 for all eight shipped on RockAuto, I have bought a set of them for my M3 with no issues, all the Bosch QR codes and serial numbers were confirmed on their site. I then bought another 10 for my M5 since the S65 ones work with a few parameters changed in the tune. Those also checked out with no issues.
danvitmon wrote
was about to say this. Injectors are $400 for all eight shipped on RockAuto, I have bought a set of them for my M3 with no issues, all the Bosch QR codes and serial numbers were confirmed on their site. I then bought another 10 for my M5 since the S65 ones work with a few parameters changed in the tune. Those also checked out with no issues.
Love that that’s a thing for the E60s now. I think mine was the test mule for making that parameter change lol.
Thanks guys, when I checked a few years ago they were $85. $392 shipped for 8 !

Edit: Cut up the t-stat tubes while removing them, you guys think it's fine to file out burrs and run it ?

Also, rejecting this Motorad unit, I'm not thrilled with the socket marks and whatever method of securing the nut they use. It appears to be swaged but it's not worth it to me to risk having to redo this
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