MS6 Suspension Data & DIY Bilstein Coilovers

[phate]

Originally Posted by MSP611 I know I will be a lil heavier than you when I do my corner balance becuz I will be full interior with some bracing minus some weight obviously from cats and a couple extra things but prob pretty close to stock, so im thinkin of doin minimum 850sF/900sR or so in the rear....

I would get corner weights first (at race weight) before deciding on rates. I've gone from 600's, to 700's, to 800's in the rear and the 800's can be a little unruly around town. If you plan to DD the car, maybe consider slightly lower rates. Performance wise, I definitely prefer the stiffer spring in the rear, and I think overall the car needs a lot more rear bias - hopefully through a stiffer rear ARB that doesn't exist yet, lol. If I want more spring than what I have now, it will likely require another revalve of the shocks.

Originally Posted by MSP611 Also other than the bump travel measurements I thought u needed a longer spring for the available 12" or so of full travel?... im sure im getting something wrong and my numbers r off, but jw why the choice of the 7" spring exactly

You need height adjusters in the rear for the shorter springs. I have some from BC Racing and they work great. 7" spring only because it's available in decent rates and works with the space we have. An 8" spring would be fine (QA1's are 8"), and they fit great with the same height adjusters.

When you run a significantly stiffer spring, your normal operating range of bump travel is decreased.

Originally Posted by MSP611 The real question is in the extra 30-50mm lowering r u wasting the space just for looks with less actual function?

Sort of. I gave my impressions of bump steer curves a page or two ago when I measured them, and I've put a lot of stock into those when deciding on height. The rear is fine being lower IF you can keep it off of the frame stops and IF you can keep the tires from rubbing, all while running proper camber settings. The front, not so much.

[MSP611]

great info @phate; this is some of the most informative suspension shit ive read, included as well the speed6 road racing thread. Ya the car will mostly be street driven but only taken out when I really wanna drive and I have a lot of nice roads and mt. driving around me with wat I grew up on....

As for corner balancing before I order, tht might be slightly hard becuz im gone 11months out of the year and only had limited time when im home... I was tryin to have everything ready when im home... I know corner balancing is ideal first but I don't know if ill have time.

[Code Monkey]

Originally Posted by MSP611 I know corner balancing is ideal first but I don't know if ill have time.

You just want corner weights first (with you in the car) without any balancing as this will determine valving and spring rates. Once you get all the suspension pieces in, you do proper alignment and corner balancing. If you cannot get all 4 corners, even just the front and rear weight would do.

[MSP611]

hmmm maybe ill have my roommate get it done... What kind of special scales do u use? or do take it somewhere?

[KevinK2]

Originally Posted by MSP611 ..... so technically @KevinK2; it would give you a lil more low? The real question is in the extra 30-50mm lowering r u wasting the space just for looks with less actual function?

The sprung CG height and track width are the only two things that can reduce the weight transfer for a specific corner speed. But unless you can correct bump steer, and adjust the F & R roll centers to reasonable heights, you can mess up the suspension geometry and degrade the handling with a 50mm drop.

.

[MSP611]

gotcha dually noted lol

[Nliiitend1]

Originally Posted by MSP611 gotcha dually noted lol

*duly*

[WetzMS3]

Originally Posted by Nliiitend1 *duly*

This guy.

[MSP611]

meh tomato, tomatoe

[Tomas]

Originally Posted by Nliiitend1 *duly*

well may be he meant to note things twice. I mean why not.

[KevinK2]

Originally Posted by MSP611 gotcha dually noted lol

Right, noted for both the front, and rear suspensions .... twice noted

[MSP611]

U got it @KevinK2;

[phate]

Autocrossed on asphalt yesterday. It's a totally different animal than the concrete I'm used to running on. Grip wasn't available like usual. I ran two sessions, one in the morning that consisted of 5 runs, and an afternoon session with 7 runs. I was mostly working tire pressures and taking tire temps and trying to reign in the oversteer that I started out with.

Current setup, as a reminder - 850F/800R springs, stock front bar, WL rear bar on stiff. -2.0° F/-1.8° R camber, 0 toe all around.

I ended up with pressures of 32.5F/33R, which is the closest I've ever had them. That gave me some manageable mid corner oversteer, but the car still has some steady state understeer. Turn in is a little numb, but I attribute that mostly to the Rivals. They weren't crisp the first time around, but the wider/slightly stretched tire this time around is definitely better.

Tire temps were kind of interesting. There was a hard, straight braking zone coming into the finish, so I think inner tire temp readings were a little hotter than they would have been otherwise, so I'm taking that into consideration. Mostly - I need more negative camber most everywhere. The inside region of the tread on the front tires was just slightly hotter than the outside by ~5° on most runs. The rear tires had almost completely even heat across the tread. With the assumption that the inner tread was slightly hotter due to the last braking zone, I want to try more negative camber to see if we can pick up more cornering power.

If that is the case, I think I can still shift more roll bias to the rear and hopefully pick up more front grip. Any additional grip up front and/or loss of grip in the rear should be countered by some added camber in the rear at the very least. On concrete, I have room to bring rear temps down since they were higher to get some rotation out of the car.

On the max camber front, we've been discussing it on our local autocross forum. There are folks running upwards of -3° without any [claimed] reduction in braking power. I have at least that much to play with, and I might be able to add in some caster by rotating the ball joints a bit. I'll work on that next weekend if I can. We have a test and tune, and should have tons of runs.

The car felt pretty good, though. Other than me completely over driving a few runs, including one spin, it was good when I drove it with smoother input. Throttle down before the apex most everywhere without inducing significant understeer, very easy and quick to correct mistakes.


This was my fastest run from the day. Check out the tire rollover, it's amazing how much it has. That's the pressure they seemed to like on that surface, and they weren't actually rolling over onto the sidewalls. They were pretty happy and pretty easy to drive.

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I've sent an email to GCDC for a recommendation of accelerometers. I tried using Harry's Lap Timer at this autocross and the last with marginal success. It did record numerous data points (both lineal and lateral) of >1.10g, and a few decel points just over 1.2g. The sampling rate is too slow to be useful, though. There are two GCDC units I'm looking at. One that is +/-2g and another that is +/-16g. The 2g unit seems totally sufficient, but they recommend the 16g one for automotive use. If they say the 2g accelerometer is OK for automotive use (I don't see why it wouldn't be), I'll get it for the higher resolution. Both have faster sampling rates than I need right now, and both look to have sufficient battery life. Maybe I can get that in before the test and tune. The HLT preview is enticing, haha.

[KevinK2]

Even with the stiff spring set-up, it appears to have more body roll than desireable. With your custom rear bar sized to match the Steeda 26mm front bar, bars would be 38% stiffer (100% with RB), roll and edge wear would be reduced. The wear on the front tires really get across the outer edges, lots of slip angle ... great camera work! I know you are going for more camber, but did you try more pressure F & R, like 36+ psi?
On the video, it looks like you were fast and slipping on the asphalt.

.

[zenit]

Originally Posted by phate Autocrossed on asphalt yesterday. It's a totally different animal than the concrete I'm used to running on. Grip wasn't available like usual. I ran two sessions, one in the morning that consisted of 5 runs, and an afternoon session with 7 runs. I was mostly working tire pressures and taking tire temps and trying to reign in the oversteer that I started out with. I ended up with pressures of 32.5F/33R, which is the closest I've ever had them. That gave me some manageable mid corner oversteer, but the car still has some steady state understeer. Turn in is a little numb, but I attribute that mostly to the Rivals. They weren't crisp the first time around, but the wider/slightly stretched tire this time around is definitely better. Tire temps were kind of interesting. There was a hard, straight braking zone coming into the finish, so I think inner tire temp readings were a little hotter than they would have been otherwise, so I'm taking that into consideration. Mostly - I need more negative camber most everywhere. The inside region of the tread on the front tires was just slightly hotter than the outside by ~5° on most runs. The rear tires had almost completely even heat across the tread. With the assumption that the inner tread was slightly hotter due to the last braking zone, I want to try more negative camber to see if we can pick up more cornering power. ... On the max camber front, we've been discussing it on our local autocross forum. There are folks running upwards of -3° without any [claimed] reduction in braking power. I have at least that much to play with, and I might be able to add in some caster by rotating the ball joints a bit. I'll work on that next weekend if I can. We have a test and tune, and should have tons of runs. ..... This was my fastest run from the day. Check out the tire rollover, it's amazing how much it has. That's the pressure they seemed to like on that surface, and they weren't actually rolling over onto the sidewalls. They were pretty happy and pretty easy to drive..

Originally Posted by KevinK2 Even with the stiff spring set-up, it appears to have more body roll than desireable. ... The wear on the front tires really get across the outer edges, lots of slip angle ... great camera work! I know you are going for more camber, but did you try more pressure F & R, like 36+ psi? .

Your tires are definitely moving, but actually less than I expected. I'm used to seeing videos of big floppy race tires or oversized street tires on an undersprung car.

I can relate to the low pressures v tire roll. I was running 32 psi on 255's on 10's and saw roll right at the outer marker for the front tires. However, I'm beginning to wonder if that the tires on the front setup are under cambered and are still overtaxing the outside edge, but due to a lack of body roll essentially scrubs the tire flat vs rolling the tread and scrubbing. I'm not sure how adding pressure would help this.

This is a something that could be looked into with a pyrometer. Didn't happen to record the raw data did you?

[phate]

Originally Posted by KevinK2 Even with the stiff spring set-up, it appears to have more body roll than desireable. With your custom rear bar sized to match the Steeda 26mm front bar, bars would be 38% stiffer (100% with RB), roll and edge wear would be reduced. The wear on the front tires really get across the outer edges, lots of slip angle ... great camera work! I know you are going for more camber, but did you try more pressure F & R, like 36+ psi? On the video, it looks like you were fast and slipping on the asphalt. .

I started around 34/36, they increased to ~36/37 and grip was down and the car was very loose. I dropped it as low as 32/32, but that seemed to be too low as it wasn't as fast or responsive.

I was ~1.7s slower than the fastest door car, so not bad imo.

Originally Posted by zenit Your tires are definitely moving, but actually less than I expected. I'm used to seeing videos of big floppy race tires or oversized street tires on an undersprung car. I can relate to the low pressures v tire roll. I was running 32 psi on 255's on 10's and saw roll right at the outer marker for the front tires. However, I'm beginning to wonder if that the tires on the front setup are under cambered and are still overtaxing the outside edge, but due to a lack of body roll essentially scrubs the tire flat vs rolling the tread and scrubbing. I'm not sure how adding pressure would help this. This is a something that could be looked into with a pyrometer. Didn't happen to record the raw data did you?

Sure did, but of course my notebook is with my autocross box, in Johanna's garage. I'll ask her to grab it. I tried to record as much as I could so I have something to look back on.

Are you coming down for the test and tune this weekend? I'll have my pyrometer if you'd like to use it. Might even have an accelerometer by then!

[KevinK2]

Originally Posted by zenit .... I can relate to the low pressures v tire roll. I was running 32 psi on 255's on 10's and saw roll right at the outer marker for the front tires. However, I'm beginning to wonder if that the tires on the front setup are under cambered and are still overtaxing the outside edge, but due to a lack of body roll essentially scrubs the tire flat vs rolling the tread and scrubbing. I'm not sure how adding pressure would help this. ....

EDITED:You see a lack of body roll for your car. From Phates video of his car, I see about 5-6 " at the wheel, in terms of max gap and min gap, and also know larger sway bars are the way to reduce roll, but with the oem front bar, and an effectively 2mm larger rear bar where the MR is .56, Phate's not getting much anti-roll from the set-up, imho.

In the tire pressure, I was wrong to suggest raising both front and rear to ~ 36+ psi, and Phates subsequent notes show that made things worse. You are right in that higher pressure would not help the front edge wear on the stetched fit tires.

Originally Posted by Phate ... I started around 34/36, then increased to ~36/37 and grip was down and the car was very loose....

With this info, I read +2 psi up front did increase front grip, and/or +1 psi at the rear decreased rear grip. So 1st logical step would be to change one variable. I'd leave the front at 34, and reduce the rear by ~2 psi. That is 34/34, and we now know Phate was best with 32.5/33. Of course this is after knowing what worked from Phate, but it's a logical path vs my quick suggestion to raise pressures to 36+.

One thing to remember is Phate's control arm bushings are close in stiffness to new oem's, so some neg camber loss is due to bushing flex in the corners, which supports the general agreement to increase neg camber.

.

[Code Monkey]

I thought autocrossers ran very high pressures in the front? Like 40-42 psi front/34 psi rear on a car like the speed6?

[phate]

Originally Posted by KevinK2 With this info, I read +2 psi up front did increase front grip, and/or +1 psi at the rear decreased rear grip. So 1st logical step would be to change one variable. I'd leave the front at 34, and reduce the rear by ~2 psi. That is 34/34, and we now know Phate was best with 32.5/33. Of course this is after knowing what worked from Phate, but it's a logical path vs my quick suggestion to raise pressures to 36+.

I typically lower one axle's pressure at a time and sort of shimmy down to those pressures. The fronts weren't happy much above 34psi, nor below the 32.5psi; both cases with close to nominal rear pressures.

You can feel it during the course, also. If you start at a decent pressure it feels great for the first segment or two, then as pressures increase as the tire heats up, the grip goes down. The tires never got above 140°F, so I definitely wasn't overheating them.

Originally Posted by Code Monkey I thought autocrossers ran very high pressures in the front? Like 40-42 psi front/34 psi rear on a car like the speed6?

Most camber limited/softly sprung/heavy cars have to in order to prevent tires from rolling over. If you don't have any of those, then you can lower until you find peak grip (nearly one in the same, if you think about it - you run the pressure that gives max grip). I never rolled the tire over onto the sidewall (even though the video might seem like it), I simply lost grip with lower pressure.

[Crarrs]

Originally Posted by Code Monkey I thought autocrossers ran very high pressures in the front? Like 40-42 psi front/34 psi rear on a car like the speed6?

Originally Posted by phate Most camber limited/softly sprung/heavy cars have to in order to prevent tires from rolling over. If you don't have any of those, then you can lower until you find peak grip (nearly one in the same, if you think about it - you run the pressure that gives max grip). I never rolled the tire over onto the sidewall (even though the video might seem like it), I simply lost grip with lower pressure.

Most of the autocrossers on here are running the widest tire they can possibly fit on a given wheel width, so they need the extra pressure to support the sidewall. I was running 245s on an 8-inch wheel, and I know I wasn't the only one. I was running 42-44 psi in the front with slightly over 1 degree of negative camber on stock springs.

With the "proper" setup of a wider wheel for a similar-width tire, you can get away with less pressure, and it will gain you traction overall versus having to run the extra pressure simply to maintain your contact patch. If I had decided to keep developing my MS3 for STX, my next 3 purchases would've been camber plates, 17x9s, and the GC coilover setup; in that order.

[KevinK2]

Good point. As I watched the stretch fit tires on Phates wheels, there was very little if any sidewall distortion. I was reminded of a similarly placed camera on a F1 machine, and due to the small wheel dia spec (26" dia on 13" dia rims), the tread would shift back and forth by an inch or two, with zero roll of the tread width! Two images:

Link, 2003/F1/Imola



2004 Imola



.

[phate]

Going to do testing this weekend with this little guy.





I got the +-2g unit. I don't think I'll ever have the car pulling 2g's unless it's in a wreck lol. This thing is dead simple. Set up a quick config file, save it, then it's one button top start and stop logging.

It will supposedly record 8-10 hours at 512Hz, but I'll be logging at 128 to start out. If it needs more, I'll bump it up for Sunday. I'm just going to log the entire day and trim the data later. Should be pretty easy.

[KevinK2]

When you were considering the 2 vs 16 g, I was wondering if the accuracy would be better with the 2g setup. With analog pressure gauges, accuracy is expressed as a % of full scale, but your g accelerometer + digital output board is likely different in acuracy vs scale. So is the 2 g more accurate vs the 16g uspeing a 2g display option?

Also, have you added neg camber for the next run? I know you did not have much time to do it.

.

[Nliiitend1]

Originally Posted by KevinK2 When you were considering the 2 vs 16 g, I was wondering if the accuracy would be better with the 2g setup. With analog pressure gauges, accuracy is expressed as a % of full scale, but your g accelerometer + digital output board is likely different in acuracy vs scale. So is the 2 g more accurate vs the 16g uspeing a 2g display option?

Considering that both the 16g and 2g accelerometers have rougly the same resolution (16-bit vs. 15-bit, respectively according to the company's website), wouldn't that stand to reason that the accuracy of the 2g model would be better (for the range of 0-2g, that is)?

[phate]

Originally Posted by KevinK2 When you were considering the 2 vs 16 g, I was wondering if the accuracy would be better with the 2g setup. With analog pressure gauges, accuracy is expressed as a % of full scale, but your g accelerometer + digital output board is likely different in acuracy vs scale. So is the 2 g more accurate vs the 16g uspeing a 2g display option? Also, have you added neg camber for the next run? I know you did not have much time to do it. .

Yes, the resolution is much better with the 2g unit for the reasons nliiitend1 said. They also said there was less noise with the 2g unit.

I did a rough test of it by putting it inside a box and turning it on all sides. Everything registered near 1g, so the device is working properly (not a perfect test, obviously, just something to make sure it wasn't giving drastically wrong info). We put it on Johanna's MS3 yesterday for ~20 runs, logging at 128Hz. I'll have to write some code to trim the logs, but the data looks good.

Today is test and tune, and I'll do a set with the current -2° camber up front, then change from there. Probably see what full negative does (should be around -3°), and maybe an in between setting if time allows.

Originally Posted by Nliiitend1 Considering that both the 16g and 2g accelerometers have rougly the same resolution (16-bit vs. 15-bit, respectively according to the company's website), wouldn't that stand to reason that the accuracy of the 2g model would be better (for the range of 0-2g, that is)?

Totally accurate, but from -2 to 2, and -16 to 16

[phate]

I have done ZERO analysis on the accelerometer data logs. I had a couple minutes this morning, so I trimmed one and plotted lateral and lineal accel over time. Looks promising.

Axis orientation, for reference:

[phate]

Wrote a bunch of code for accelerometer data analysis. I'll do a full write up of how I'm generating these graphs if anyone is interested. These are showing the average total acceleration every 5° (+- 2.5° of every 5°, starting at 0°), along with the standard deviation at that angle.

Edit: These are your typical g-g diagrams where braking is +y direction and turning left +x direction.

Prior to changing the alignment:


After adding negative camber in the front end:


Johanna driving the car:




I think my next step is to do some averaging between runs of the same driver/setup and compare from there.

[phate]

I autocrossed the 6 last Sunday without any suspension changes made from the last time. I did, however, realize the week before that when we swapped the turbo a couple months ago that I hooked up the boost controller wrong and I was only getting spring pressure I so rarely go full throttle except at autocross that I never noticed. Needless to say, running double the boost pressure makes the car feel really fast again, haha.

The course was exceptionally fast. I was in third gear probably more than 70% of the course with only 1 downshift to 2nd for a 180° turnaround pivot cone. My driving wasn't the tidiest and I managed to only get 1 clean run - my slowest run of the day. My fastest run was another 1.3s faster than my clean run, and I think it is within reason to say it was achievable had I been driving a little better. But, that 1 clean run was good enough to take the class by a little over .7s.

I ended up 6th overall, and had I driven that fast run cleanly it would have put me 2nd overall. We'll see in a week whether it was a fluke or not (haha).

Accelerometer data showed that I was trail braking slightly more, but I need to work on it more.

It was my nephew's first time at an autocross so I had the camera pointing backwards to get his reaction. It's too bad he had the visor down (he's in runs 1, 2, and 5). Run 3 has a pretty good reaction, but the camera died just a little ways in. Run 4 is our very own @zenit;! It also shows me that I'm still a little choppy with the steering at some points. And take a look at the seat movement!

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[MSP611]

What are u usually racing against in the class u r in?

Also what is Ur harness mounted to? U have a harness bar?? Is there any harness we can get and mount without a harness bar?? Like something with longer straps we can mount to the floor or something?

[Crarrs]

Originally Posted by MSP611 Is there any harness we can get and mount without a harness bar?? Like something with longer straps we can mount to the floor or something?

Schroth Rallye 3 and Rallye 4 are made for exactly that purpose. I just sold mine here last month. It works very well.

[ItsNox]

Originally Posted by phate It was my nephew's first time at an autocross so I had the camera pointing backwards to get his reaction. It's too bad he had the visor down (he's in runs 1, 2, and 5). Run 3 has a pretty good reaction, but the camera died just a little ways in. Run 4 is our very own @zenit;! It also shows me that I'm still a little choppy with the steering at some points. And take a look at the seat movement! http://youtu.be/y7miouPPn0o

Were his under-titties sweaty after the run? I know how he feels. Except we were on the side of a mountain! Look at his fist all clenched and holding on for dear life to the handle and trying to wedge himself in there in that la-z-boy no-support passenger seat.

OH FUN TIMES CANT WAIT TO DO IT AGAIN

[phate]

Originally Posted by MSP611 What are u usually racing against in the class u r in? Also what is Ur harness mounted to? U have a harness bar?? Is there any harness we can get and mount without a harness bar?? Like something with longer straps we can mount to the floor or something?

My class typically consists of muscle cars (mustangs - including the new 5.0, camaros). It includes the AWD "boost buggies" - WRX (non-STi) and DSM's - but they rarely run this class in my region. We're allowed to run DOT RComp tires, so the muscle car guys have mostly gone to the 315 or 335 wide Hoosier A6. The competition has gotten pretty serious in this class, locally. 2 years ago when I was considering the switch the class was pretty soft. I think a few of us noticed and made the switch all at once and it's made for some great competition and typically the biggest class to compete in.


The harnesses:

Last year I borrowed @naoandlater;'s Schroth Rallye Cross 4 point harness (this one). I REALLY liked this harness and hated having to give it up. The mounting tabs are bendable and work great.

I'm currently running a Corbeau 4 point harness (this one) that I bought as a replacement for the Schroth. This harness is less than half the price of the Schroth and looked to be a good alternative. The mounting tabs are ~1/8" steel and pretty short, so impossible to bend by hand. They make it a little more of a pain to mount everything, but it's doable.

Both harnesses mount similarly, but like I said the Corbeau tabs make it a pain. For the Schroth I used the two rear seat bracket bolts of the front seat to mount the lap belt (going into the chassis tub). The bendable tabs make this possible. For the Corbeau, I'm using the lower mounting point for the front seat seat belt to mount the lap belt's left side, and the rear seat bracket bolt to mount the right side (same as Schroth). The shoulder harness mounting points are the same between the two - I'm using the rear seat belt lower mounting points directly behind the driver.

Both of the harnesses let you push the belt out of the way onto the rear floor and let you keep the 3 point functionality for DD use. I'm really leery of using 4 points on the street, even though both say they are DOT approved (The Corbeau harness came with a letter stating this, I can't seem to find the approval on their site).


I've looked into the harness bar in conjunction with lighter seats (true racing seats need a mounting point behind the shoulders). I asked a racecar fab shop how they would go about it and what it would weigh and for me it doesn't seem worth it. It would likely end up in a net gain of weight, even with super light racing seats (carbon fiber craziness).

[Code Monkey]

No freaking way you would gain weight with a harness bar, the driver power seat is like 65 lbs IIRC.

[phate]

Originally Posted by Code Monkey No freaking way you would gain weight with a harness bar, the driver power seat is like 65 lbs IIRC.

The Sport driver seat is 45lb and the passenger seat is 41, total of 86. Figure the lightest carbon fiber seat with padding weighs 10lb each, plus brackets and hardware for 15lb each (guessing on bracket weight). That's 30lb for the two, leaving only 56 lb for a 4 point bar.


Aluminum racing seats weigh more and eat into that margin.

[MSP611]

Originally Posted by phate My class typically consists of muscle cars (mustangs - including the new 5.0, camaros). It includes the AWD "boost buggies" - WRX (non-STi) and DSM's - but they rarely run this class in my region. We're allowed to run DOT RComp tires, so the muscle car guys have mostly gone to the 315 or 335 wide Hoosier A6. The competition has gotten pretty serious in this class, locally. 2 years ago when I was considering the switch the class was pretty soft. I think a few of us noticed and made the switch all at once and it's made for some great competition and typically the biggest class to compete in. The harnesses: Last year I borrowed @naoandlater;'s Schroth Rallye Cross 4 point harness (this one). I REALLY liked this harness and hated having to give it up. The mounting tabs are bendable and work great. I'm currently running a Corbeau 4 point harness (this one) that I bought as a replacement for the Schroth. This harness is less than half the price of the Schroth and looked to be a good alternative. The mounting tabs are ~1/8" steel and pretty short, so impossible to bend by hand. They make it a little more of a pain to mount everything, but it's doable. Both harnesses mount similarly, but like I said the Corbeau tabs make it a pain. For the Schroth I used the two rear seat bracket bolts of the front seat to mount the lap belt (going into the chassis tub). The bendable tabs make this possible. For the Corbeau, I'm using the lower mounting point for the front seat seat belt to mount the lap belt's left side, and the rear seat bracket bolt to mount the right side (same as Schroth). The shoulder harness mounting points are the same between the two - I'm using the rear seat belt lower mounting points directly behind the driver. Both of the harnesses let you push the belt out of the way onto the rear floor and let you keep the 3 point functionality for DD use. I'm really leery of using 4 points on the street, even though both say they are DOT approved (The Corbeau harness came with a letter stating this, I can't seem to find the approval on their site). I've looked into the harness bar in conjunction with lighter seats (true racing seats need a mounting point behind the shoulders). I asked a racecar fab shop how they would go about it and what it would weigh and for me it doesn't seem worth it. It would likely end up in a net gain of weight, even with super light racing seats (carbon fiber craziness).

Great fuckin info @phate;

I'm really interested in the harnesses for hard canyon driving etc etc plus I kind of like the look. In the current format u have them mounted (corbeaus or rallye), do the belts get in the way of the passengers leg room or make any fuss? Did u change the mount bolts u used for longer ones on the brackets??

[phate]

Originally Posted by MSP611 Great fuckin info @phate; I'm really interested in the harnesses for hard canyon driving etc etc plus I kind of like the look. In the current format u have them mounted (corbeaus or rallye), do the belts get in the way of the passengers leg room or make any fuss? Did u change the mount bolts u used for longer ones on the brackets??

I rarely have back seat passengers, but I can imagine they would be stepping on the harness.

The Schroth doesn't require any new or different hardware. Stock bolts are sufficient because the tabs are pretty thin. The Corbeau harness does require longer bolts, but they are supplied with the harness.

[MSP611]

Hmmm well thts shitty lol Damn backseat passengers... I don't really drive with them either and don't like to in a matter of fact. All my friends think I'm weird for having a sedan and not liking to drive people lol.

[phate]

Here's the usual mess.

[MSP611]

Could u tuck it under Ur seat lol??

[KevinK2]

Just a brief complement on your smooth driving style, and looking ahead on the course. I can see it from your normal videos, and this one with the camera facing the driver and passenger. Is that an ugraded turbo? It's amazing how you can stay in 3rd and still pull out hard from some slow corners.

Who was the passenger in run 3 ???

Back in history when I competed for class titles, I also had close competition, that I beat by tenths. I had plotted all the time differentials, and found I had a significant gain after spending a day running HSDE's at Summit Point's 2 mile road course.

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