Track forum general chit chat.

[roastbeef]

Originally Posted by DRLane

Only challenge is to meet regulations you'd still have to use the larger tubing even with Jamie's T45 cage. The safety regs don't recognize the increased strength, thus it would weigh at least as much as DOM. But I do love his work!

I'll have to figure that out when the time comes. At the moment, I don't think I'll be a regular participant in any competitions.

[DRLane]

Originally Posted by roastbeef

I'll have to figure that out when the time comes. At the moment, I don't think I'll be a regular participant in any competitions.

Sure maybe not immediately, but building a cage that fundamentally can't pass tech in any organization would be questionable financial choice. Would render the car almost worthless if there came a time you needed to sell the car for whatever reason.

[derbo]

Originally Posted by Bimmer Barney

This crash video is why I'm on the fence about only doing seats, qfp harnesses and a hans. IMO it needs to be an entire engineered system. Either all in or stick with the millions of dollars and hours that bmw spent on the stock safety ecosystem.

Full race car system, or track it using stock restraint system and drive knowing you're not in a race car.

My opinion has been shaped by prior motorcycle racing and a career in risk management. YMMV. I walked away from a 90mph high side on track at chuckwalla. Very lucky.

SYT_Shadow mentioned this from a Schroth document. I do think there is a place for bucket + harness bar + harness even without a cage. Yes, a full containment system is the best.

I have to pause here to address the elephant in the room. Many people feel that unless you have a full cage or at least half a welded cage, race seats are instant screaming death on a stick. Those people also say it's better to run 3 points of the Schroth QFP than a 6 point and a harness bar.
I disagree completely, but here is what Schroth has to say about it. They may know a thing or two about safety.
Cliff notes: 6 points are safer than 3 points, period.
https://www.schrothracing.com/docs/TechTactics.pdf
Edit December 2020: the pdf is no longer on the website but here are the interesting pages:

https://www.m3post.com/forums/showthread.php?t=1394068

[spooni]

Originally Posted by slcook54

Will have pics of my TCD cage on Friday.

Does he really make you run a banner on your car? And make you park next to him when you do track days together?

[SYT_Shadow]

Originally Posted by derbo

SYT_Shadow mentioned this from a Schroth document. I do think there is a place for bucket + harness bar + harness even without a cage. Yes, a full containment system is the best.




https://www.m3post.com/forums/showthread.php?t=1394068

It could not be any more clear, but people still use the 'I'll duck' thought process...

[spooni]

Once I got the boogery bolts in, the rest went in perfectly. Great fitment. Putting in the harnesses and new Sparco grid Q tonight! First time doing a TA event on Saturday(with OnGrid so not too fancy)

[tsk94]

Guys - has anyone been running rear coilovers on a non-reinforced E9X M3 chassis for an extended period of time and can report back their experiences? On my E92 race car, we reinforced the strut towers and the cage was tied into it, but for a track car, it would be nice if this wasn't needed. I have no issue doing it if required but wanted to hear back if anyone has any input.

For reference, the rear spring rate I'd be looking to run would be ~700-750 (coilover, of course..)

[DRLane]

Originally Posted by tsk94

Guys - has anyone been running rear coilovers on a non-reinforced E9X M3 chassis for an extended period of time and can report back their experiences? On my E92 race car, we reinforced the strut towers and the cage was tied into it, but for a track car, it would be nice if this wasn't needed. I have no issue doing it if required but wanted to hear back if anyone has any input.

For reference, the rear spring rate I'd be looking to run would be ~700-750 (coilover, of course..)

dogbone

[warp10]

Originally Posted by tsk94

Guys - has anyone been running rear coilovers on a non-reinforced E9X M3 chassis for an extended period of time and can report back their experiences? On my E92 race car, we reinforced the strut towers and the cage was tied into it, but for a track car, it would be nice if this wasn't needed. I have no issue doing it if required but wanted to hear back if anyone has any input.

For reference, the rear spring rate I'd be looking to run would be ~700-750 (coilover, of course..)

I'm running a true coil on the rear. No issues so far.

[Gossypiboma]

Originally Posted by derbo

SYT_Shadow mentioned this from a Schroth document. I do think there is a place for bucket + harness bar + harness even without a cage. Yes, a full containment system is the best.




https://www.m3post.com/forums/showthread.php?t=1394068

So they don't advise using their 4 point QFP with a Hans, or maybe that came out afterwards?

I'm definitely no expert but I feel a 4 point harness and a Hans seems pretty safe.

[Tommysalami]

Originally Posted by Gossypiboma

So they don't advise using their 4 point QFP with a Hans, or maybe that came out afterwards?

I'm definitely no expert but I feel a 4 point harness and a Hans seems pretty safe.

I think that power point is really old. Otherwise Schroth wouldn't advertise the QFP as being compatible with a Hans

[roastbeef]

Originally Posted by tsk94

Guys - has anyone been running rear coilovers on a non-reinforced E9X M3 chassis for an extended period of time and can report back their experiences? On my E92 race car, we reinforced the strut towers and the cage was tied into it, but for a track car, it would be nice if this wasn't needed. I have no issue doing it if required but wanted to hear back if anyone has any input.

For reference, the rear spring rate I'd be looking to run would be ~700-750 (coilover, of course..)

Me, but not much track time. I was told it wasn't an issue on these cars.

[///Mobbin]

Originally Posted by tsk94

Guys - has anyone been running rear coilovers on a non-reinforced E9X M3 chassis for an extended period of time and can report back their experiences? On my E92 race car, we reinforced the strut towers and the cage was tied into it, but for a track car, it would be nice if this wasn't needed. I have no issue doing it if required but wanted to hear back if anyone has any input.

For reference, the rear spring rate I'd be looking to run would be ~700-750 (coilover, of course..)

I recently started running a coilover rear on a non-reinforced chassis. Checked in with a number of folks before ordering and no one had any issues to report.

[derbo]

Originally Posted by Tommysalami

I think that power point is really old. Otherwise Schroth wouldn't advertise the QFP as being compatible with a Hans

Yah the Schroth document is prior to their QFP lineup.

[Lozza47]

Originally Posted by spxxx

You're running 285/35 tires? That's a pretty uncommon size unless it's the Slick equivalent? Seems like that'd rub much more than a 295/30?

It's all about that 5in spring (no helper) to keep the perch above the tire... or monster truck ride height

Sorry to butt in here again, but regarding the 285/30/18 and 295/30/18 - the difference is diameter is around 6mm approx, I'm guessing this won't fix up the speedometer calculation inconsistency as much as running a 285/35 or 295/35.
I'm honestly about 13kms out when travelling at 100km/h. The final gear ratio has changed dramatically I'm beginning to think I should go back to 285/35 Zestinos.
Anyone running 295/30 and does that extra 6mm make any difference in speed calc?

[spxxx]

Originally Posted by Lozza47

Sorry to butt in here again, but regarding the 285/30/18 and 295/30/18 - the difference is diameter is around 6mm approx, I'm guessing this won't fix up the speedometer calculation inconsistency as much as running a 285/35 or 295/35.
I'm honestly about 13kms out when travelling at 100km/h. The final gear ratio has changed dramatically I'm beginning to think I should go back to 285/35 Zestinos.
Anyone running 295/30 and does that extra 6mm make any difference in speed calc?

Negligible but yes it'll make a difference, this is a pretty good calculator. https://tiresize.com/calculator/

[Lozza47]

Originally Posted by spxxx

Negligible but yes it'll make a difference, this is a pretty good calculator. https://tiresize.com/calculator/

I've been using that Speedo error calculator on that site and the difference between stock 265/35/19 and 285/30/18 should be about 6km/h but I'm getting a 13km/h difference, so was just seeing what others are getting IRL. Maybe the Nankang CR-S wheel diameters are a bit smaller than the average??

[b4hand]

Originally Posted by tsk94

Guys - has anyone been running rear coilovers on a non-reinforced E9X M3 chassis for an extended period of time and can report back their experiences? On my E92 race car, we reinforced the strut towers and the cage was tied into it, but for a track car, it would be nice if this wasn't needed. I have no issue doing it if required but wanted to hear back if anyone has any input.

For reference, the rear spring rate I'd be looking to run would be ~700-750 (coilover, of course..)

No Issues here, only been like 8 months though. OG Shark did the install and didn't see a need to reinforce.

[911r]

Originally Posted by tsk94

Guys - has anyone been running rear coilovers on a non-reinforced E9X M3 chassis for an extended period of time and can report back their experiences? On my E92 race car, we reinforced the strut towers and the cage was tied into it, but for a track car, it would be nice if this wasn't needed. I have no issue doing it if required but wanted to hear back if anyone has any input.

For reference, the rear spring rate I'd be looking to run would be ~700-750 (coilover, of course..)

I put ~30k miles on a car with true rear dampers (MCS) … car also had 15-25 track days on the same dampers (previous ownership).

Zero issues.

[spxxx]

Ran coilovers + 900lbs divorced springs for ~4yrs on my previous E82 with nearly identical suspension geometry as the E9x.

[tsk94]

Thanks everyone for the input. That's good to hear

[Bartledoo]

Originally Posted by tsk94

Thanks everyone for the input. That's good to hear

Got another M3?!