Track forum general chit chat.

[evilspiritM3]

Originally Posted by Shmelgy

For those of you wondering- here's a pic of 295/30/18 Toyo RR on 18x10 et 25. Had no rubbing issues since I raised the spring, and the tires did have a bit of a bulge to them.

Ended up getting a blowout on turn 6 at big willow, which made me go off pretty badly. Destroyed the front splitter and the wheel got bent pretty badly. I've been wanting wider wheels and have gotten tired of constantly bending apexs, so finally pulled the trigger on some forgelines!

What size/spec forgelines?

[Move Over]

Originally Posted by Shmelgy

For those of you wondering- here's a pic of 295/30/18 Toyo RR on 18x10 et 25. Had no rubbing issues since I raised the spring, and the tires did have a bit of a bulge to them.

Ended up getting a blowout on turn 6 at big willow, which made me go off pretty badly. Destroyed the front splitter and the wheel got bent pretty badly. I've been wanting wider wheels and have gotten tired of constantly bending apexs, so finally pulled the trigger on some forgelines!

What size spring is this and are you running a helper?

[NoCarrier]

I'm at Laguna Seca today and I've cooked the brakes (OEM w/ PFC08 pads) in two different sessions... pedal to the floor in this most recent one. This has never been a big problem for me, even at this track which is notoriously hard on brakes.

I have always run Castrol SRF or PFC brake fluid in the past, but shipping delays caused me to use Motul 660 this time around. Would the fluid change be enough to cause this? Or could there be something else going on?

[roastbeef]

Maybe you're just going faster this time?

[NoCarrier]

I am, by a few seconds (different tires). But still... something seems off.

[Move Over]

Originally Posted by NoCarrier

I am, by a few seconds (different tires). But still... something seems off.

In my experience, SRF to motul (even 660) is drastically different. I'm not a huge fan of the compressibility of SRF, but have always had issues with Motul boiling. I know the boiling point is high, but I have reason to believe that number is inflated. I've never had an SRF boiling issue.

[NoCarrier]

Originally Posted by Move Over

In my experience, SRF to motul (even 660) is drastically different. I'm not a huge fan of the compressibility of SRF, but have always had issues with Motul boiling. I know the boiling point is high, but I have reason to believe that number is inflated. I've never had an SRF boiling issue.

I always wondered if the SRF worship was a bit over the top. I bought the 660 based on the numbers but I don't think the numbers tell the whole story. The brakes have just felt crappy all day. Back to SRF or PFC for sure.

Maybe it's time to put the car on the roastbeef diet. I've got a uni-bit and some spare time.

[Redd]

Motul is a Tier2 fluid, SRF is a Tier1 fluid. If you like SRF but find it a bit too spongy, try Endless RF650.

https://thebuildjournal.com/tech-gui...view-analysis/

[chocstraw]

edit: Motul 600/660 is only good immediately after flushing, even then it's not great. It's borderline unsafe after a few months. I've cooked it on the streets on a hot summer day on shitty tires.

I'm sure this has been asked a thousand times but it's not exactly easy to search for. Is there any gains or benefit from some simple ducting into the wheel well like the 335i has? I know that it's ideal to hook it up to the rotor shield but would something like this help marginally? I have the hardware to do it laying around.

Seems like an oversight that the 335i came with more brake cooling than the M3.

[roastbeef]

it will help, but there isn't a great place for the ducting. hard motorsport makes a ducting kit that makes you cut into the fender liner and the scoops for the lower air intake, and transmission cooler. it is 3d printed and is poor quality. it doesn't last long and disintegrates, ruining four expensive oem panels.

[Redd]

Or you can do my 911 GT3 brake duct/scoop retrofit. It's cheap and I don't know if it works 100% but I know it doesn't hurt.

[rhyary]

Originally Posted by roastbeef

it will help, but there isn't a great place for the ducting. hard motorsport makes a ducting kit that makes you cut into the fender liner and the scoops for the lower air intake, and transmission cooler. it is 3d printed and is poor quality. it doesn't last long and disintegrates, ruining four expensive oem panels.

Autocouture is installing brake ducts on my car as we speak. I don't know if it will make the brakes more effective, but I would have a tangible results if it actually works and worth the expense and effort.

My inner brake pads are being used at much faster rate than the outsides. I have learned to flip them, but that doesn't prevent the accelerated wear.

Brembo engineer confirmed that heat would be the first reason after a stuck caliper, which I don't have and it happens on both fronts.

I should be able to tell going forward if ducting helps.

[Move Over]

Originally Posted by NoCarrier

I always wondered if the SRF worship was a bit over the top. I bought the 660 based on the numbers but I don't think the numbers tell the whole story. The brakes have just felt crappy all day. Back to SRF or PFC for sure.

Maybe it's time to put the car on the roastbeef diet. I've got a uni-bit and some spare time.

I personally don't like the feel of SRF, as the hot compressibility levels aren't great. I switched the endless and the pedal stays rock solid and does not get a spongy (don't read that as boiling) feel when hot. I really liked endless for the first 3 days I was on it.

In regards to ducting, I had a very long conversation with Jeff Ritter at Essex when I bought my AP kit, and he had a great point that 90% of these duct kits on the market do not feed air into the right place as they are shooting air straight at the face of the rotor which really does nothing and actually can cause more harm than good. The duct needs to feed cool air into the rotor vanes to be effectively cooling. This article was written after our conversation, definitely worth the read. He basically said unless I am running a 2.5" hose or larger directed at the rotor vanes, it's worthless. He advised me to ditch all dust shields and maybe do an air diverter kit instead.

https://www.essexparts.com/news-blog...n-my-track-car

[Move Over]

Originally Posted by Redd

Or you can do my 911 GT3 brake duct/scoop retrofit. It's cheap and I don't know if it works 100% but I know it doesn't hurt.

Can you link me please? I have seen it around but cannot seem to find it

[Redd]

Originally Posted by Move Over

Can you link me please? I have seen it around but cannot seem to find it

Here you go:
https://www.m3post.com/forums/showthread.php?t=1406400

[slowdown_dan]

While we're talking about airflow, has anyone flat bottom'd their car, or at least partially? I know it's commonplace to run a front splitter and rear diffuser, but what about connecting all that open space in between with some aluminum or cf panels attached by rivnuts, and possibly a few naca ducts placed in spots where some low drag airflow could benefit certain components (thinking each corner for the brakes)

Obviously a full flat bottom would see the largest aero gains, but can you cover up the exhaust section if you add in some naca ducts along the way for exhaust cooling? I came across this picture as I was looking for an example of this being done to our chassis. It's not a full flat bottom, but it's getting there.

Anyway, I wish there was a way to attach a full fluids car to a rotisserie and tip it over to get to work measuring and fabricating.

[Kelse92]

I have but have still not yet installed the Porsche brake duct mod. But I will say that more and more people seem to be ditching the traditional brake "ducting" in favor of air "deflectors" like those.

[Move Over]

Originally Posted by Kelse92

I have but have still not yet installed the Porsche brake duct mod. But I will say that more and more people seem to be ditching the traditional brake "ducting" in favor of air "deflectors" like those.

It even appears vorshlag is in the process of making deflectors... that should speak a bit of how they feel.

[dparm]

Originally Posted by Move Over

It even appears vorshlag is in the process of making deflectors... that should speak a bit of how they feel.

The Vorshlag guys are awesome and will do it right. I have visited their shop a few times to see the operation and understand how they approach things. Maybe Kelse92 can loan her car as a test mule!

[tsk94]

Deflectors are nice for the ease of install and relative effectiveness without being intrusive. Brake ducting can be a pain to route and often will limit steering lock so you don't squash the hoses. However, the deflectors aren't nearly as efficient. Directly the air into the general vicinity of the rotor will help, but isn't nearly as effective as ducting that directs the air to center of the hub and allows the rotor to pull the cool air through it properly.

Good option for a dual purpose car, but ultimately not the solution if you're really struggling with overheating.

[StripclubDJ]

Happy Monday funday

[Bartledoo]

Originally Posted by StripclubDJ

Happy Monday funday

Let's see those endplates though...