Track forum general chit chat.

[SAMM3Y]

Originally Posted by bigjae1976

Aren't those mounts are steel or stainless steel? I would use a matching material and not aluminum I would not want just use a spacer either. That may cause the bolts to side load.

IMO, those mounts are a bad design because they will cause normally sized people to be way too low.

"Planted" offer 1/4" spacers made out of aluminum and the macht schnell mounts are made of aluminum too which are about an 1" thick, both t6061. .just to clarify I would drill and maybe even tap matching holes through the spacers for the rest of the hardware. Not just sandwich them in there, do you still think that would be an issue?

[bigjae1976]

Originally Posted by SAMM3Y

"Planted" offer 1/4" spacers made out of aluminum and the macht schnell mounts are made of aluminum too which are about an 1" thick, both t6061. .just to clarify I would drill and maybe even tap matching holes through the spacers for the rest of the hardware. Not just sandwich them in there, do you still think that would be an issue?

I'd make the spacers big enough to maintain the surface area contact. So it would likely be a big square. I'm not sure if BK designed those seats with a spacer in mind. I'd call and ask just to be sure. Even with a spacer. You're putting more leverage on the bolts.

Remember, you're asking more out of your mounts with track speeds and stiff fixed back seats. I also think the Macht Scnell and Vac aluminum floor mounts suck. Remove the bolt a couple of times and the aluminum where the bolt sits galls and there's about 1/8 of soft aluminum under part of the bolt head.

I made my own. Wasn't hard and costs $30 in 3/4" thick 4" wide billet aluminum. Aluminum is easy to drill.

[macdude357]

Here is a pic of my bk mounts with my OEM sliders to get an idea of how high they are. These are the brackets for the Cobra Nogaro seats. I weighed the whole piece and it's 14 lbs. So about 36 lbs including the seat

[ApexWheels]

Originally Posted by kayha12

On the floor mounts I have it at the "highest" setting, could mess around with the front bolts but that would just tilt the seat back.. I can't imagine anyone wanting to sit any lower than this unless they are like 6'7"+ haha

Our cage fabricator just installed my RaceTech seats and BK mounts (direct to floor) and I am having the same issue. I'm 5'11" and was looking forward to a lower seating position, however, I am a bit too low right now.

Looking into possible solutions.

- Ryan

[bigjae1976]

Originally Posted by macdude357

Here is a pic of my bk mounts with my OEM sliders to get an idea of how high they are. These are the brackets for the Cobra Nogaro seats. I weighed the whole piece and it's 14 lbs. So about 36 lbs including the seat

Did you steal your kid's ruler? Lol

[M3MPH1S]

Originally Posted by ApexRaceParts

Our cage fabricator just installed my RaceTech seats and BK mounts (direct to floor) and I am having the same issue. I'm 5'11" and was looking forward to a lower seating position, however, I am a bit too low right now.

Looking into possible solutions.

- Ryan

Tbh the real fix to the issue would be if BK would offer a "tall" version. I know OMP has both normal and tall versions of their brackets

[dogbone]

Originally Posted by ApexRaceParts

Our cage fabricator just installed my RaceTech seats and BK mounts (direct to floor) and I am having the same issue. I'm 5'11" and was looking forward to a lower seating position, however, I am a bit too low right now.

Looking into possible solutions.

- Ryan

When I bought a Recaro SPG seat, I originally went with the Recaro seat mount. It was SOOO low, I could barely see out the bottom of the windshield. And I’m 5’10”. No good. I got the Macht Schnell seat mount and it offered a bunch of seat height options. Works great. Haven’t worried about it since.

[ApexWheels]

Originally Posted by dogbone

When I bought a Recaro SPG seat, I originally went with the Recaro seat mount. It was SOOO low, I could barely see out the bottom of the windshield. And I’m 5’10”. No good. I got the Macht Schnell seat mount and it offered a bunch of seat height options. Works great. Haven’t worried about it since.

The BK mounts also offer a range of height options, I think the issue is that their one-piece design does not net you the same height as a two-piece system regardless if you use the highest mounting points.

IIRC, RECARO seats come with their side mounts but you then need to source your own base. Macht Schnell is also a two-piece design.

- Ryan

[M3ANMACHINE]

Originally Posted by dogbone

It's not a repave. They:

-filled the cracks with tar. When it's cold out, the tar is bumpy and gives the feeling that your suspension is really rough and stiff. Later in the day, the tar in the cracks was pulling up as the cars drove over it and the tar slapped the underside of the cars. I show a pic below of a Lambo in front of me pulling up the tar. I remember seeing the tar slapping around as cars in front of me drove over it.
-painted the surface black. It definitely is much nicer to look at. I show some comparison pix below of how it used to look versus how it looks now.
-fixed the berms a bit and painted them.
-Painted white lines along the edge of the track
-Painted walls along the track

I believe what they did is 99% for the sake of better visuals. It's definitely nicer to look at. But there's virtually no difference in grip. And the track is still a complete cheese grater to tires. No change there. I corded a very decent set of tires far too quickly there last Sunday, and I was rotating the tires.

But the black surface looks super fancy in pictures and videos!.......

So they basically polished a turd? nice

[OG Shark]

Plan to move up to a 305 square setup shortly - would an 18" x 11" wheel work or is 10.5" a safer choice? JRZ Pro, will go to a 5" spring & will run as much camber as needed. Would like to run the same offsets - will run spacers if necessary as well.

[roastbeef]

The 11 would be a better choice for correct tire fit.
I'm not there yet, but if you're fitting 305's, I'd say it's best to do it correctly and not compromise. Might not be a huge difference, but it is probably more ideal. I'd rather have a properly sized lesser width tire than a squishy sidewall.

[OG Shark]

Originally Posted by roastbeef

The 11 would be a better choice for correct tire fit.
I'm not there yet, but if you're fitting 305's, I'd say it's best to do it correctly and not compromise. Might not be a huge difference, but it is probably more ideal. I'd rather have a properly sized lesser width tire than a squishy sidewall.

Yeah agree would prefer to go with 11 - and sounds like should fit in the right offset - just hoping to verify before spending that money

[dogbone]

Originally Posted by jktx

Plan to move up to a 305 square setup shortly - would an 18" x 11" wheel work or is 10.5" a safer choice? JRZ Pro, will go to a 5" spring & will run as much camber as needed. Would like to run the same offsets - will run spacers if necessary as well.

I have JRZ and I've been running fat tires up front for years now.

If the 305 tire that you want to run is a Pirelli DH, then a 10.5" rim is perfectly fine to run. Pirelli DH 305 tires run narrow, if anything. I have found no compromise by running Pirelli DH 305 on 10.5". The tire is responsive and fast, wears nicely and the tire sidewall of a 305/645/18 Pirelli is not stretched or pinched on 10.5". It looks very comfortable on there---ready for any type of load.

Let's look at DH 305 tires under load on track on a 10.5" rim, in this case, Titan 7 rims. This photo is taken with the passenger side tires taking serious load on the Auto Club Speedway Oval going at least 140mph at the time of the photo. We're seeing high-G's and high speeds on a banked oval. I can hardly think of a better picture to look at of a tire sidewall under a long duration of extreme load. The sidewalls look perfect on a 10.5" rim. No weird stretching or pinching or bulging or tucking or strangeness. You would have a hard time finding a moment where a tire sees more prolonged high stress than in this moment and we have it captured in a very clear picture and everything looks really great here.



A BFGoodrich R1S 285/30/18 is wider than a 305/645/18 Pirelli DH and that works fine on a 10.5" rim fine too. So, I believe that it is not necessary to run an 11" rim with Pirelli DH 305. (There's no safety issues as far as a 305 tire mounted on either of those rims.)

With an 11" rim in the front, you will force yourself to deal with fitment and rubbing challenges. You're just running out of room near the spring perch on the inside and the fender on the outside with an 11" rim. The 10.5" rim with 305 already rubs everything in the wheel well as it is. An 11" rim will just make it worse. Remember, just because a rim fits on a car when it sits in your garage does not mean that you can turn the steering wheel on a tight corner and then compress the suspension during high-G moments--especially if the car has been significantly lowered.

My advice: On the E9x M3 platform (without any widebody mods), don't go wider than 10.5" on the front.

[roastbeef]

Originally Posted by slicer

5mm with hub extensions. You sure they aren't 10mm?

I was way wrong!

Anyone want these?

[slicer]

Originally Posted by roastbeef

I was way wrong!

Anyone want these?

Lol - 17mm is just a little more than 5 mm

[roastbeef]

I think I was thinking 0.5". Lol

[bigjae1976]

Originally Posted by macdude357

Here is a pic of my bk mounts with my OEM sliders to get an idea of how high they are. These are the brackets for the Cobra Nogaro seats. I weighed the whole piece and it's 14 lbs. So about 36 lbs including the seat

Here's a pic of how tall my homemade floor mounts and Sabelt side brackets are.

[OG Shark]

Originally Posted by dogbone

I have JRZ and I've been running fat tires up front for years now.

If the 305 tire that you want to run is a Pirelli DH, then a 10.5" rim is perfectly fine to run. Pirelli DH 305 tires run narrow, if anything. I have found no compromise by running Pirelli DH 305 on 10.5". The tire is responsive and fast, wears nicely and the tire sidewall of a 305/645/18 Pirelli is not stretched or pinched on 10.5". It looks very comfortable on there---ready for any type of load.

Let's look at DH 305 tires under load on track on a 10.5" rim, in this case, Titan 7 rims. This photo is taken with the passenger side tires taking serious load on the Auto Club Speedway Oval going at least 140mph at the time of the photo. We're seeing high-G's and high speeds on a banked oval. I can hardly think of a better picture to look at of a tire sidewall under a long duration of extreme load. The sidewalls look perfect on a 10.5" rim. No weird stretching or pinching or bulging or tucking or strangeness. You would have a hard time finding a moment where a tire sees more prolonged high stress than in this moment and we have it captured in a very clear picture and everything looks really great here.



A BFGoodrich R1S 285/30/18 is wider than a 305/645/18 Pirelli DH and that works fine on a 10.5" rim fine too. So, I believe that it is not necessary to run an 11" rim with Pirelli DH 305. (There's no safety issues as far as a 305 tire mounted on either of those rims.)

With an 11" rim in the front, you will force yourself to deal with fitment and rubbing challenges. You're just running out of room near the spring perch on the inside and the fender on the outside with an 11" rim. The 10.5" rim with 305 already rubs everything in the wheel well as it is. An 11" rim will just make it worse. Remember, just because a rim fits on a car when it sits in your garage does not mean that you can turn the steering wheel on a tight corner and then compress the suspension during high-G moments--especially if the car has been significantly lowered.

My advice: On the E9x M3 platform (without any widebody mods), don't go wider than 10.5" on the front.

The info is much appreciated. While Pirelli DH's are in the future it is still going to be awhile before I make that jump. I have been running square 275/35/18 NT01's but now that I have the room I want to increase the width but stay with a fairly comparable level of tire. NT01 comes in pretty tall at 305/35 so I'm going to try the Yokohama ADVAN A052 in 295/30/18 when they come back in stock. They reportedly run wide so more like a 305 width. Since it's going to be multiple sets I would like these wheels to be my endgame fitment & be able to transition well from here up the ladder eventually to the DH's.

Do you run any spacers with the Titan 7's?

Thanks!

[dogbone]

Originally Posted by jktx

The info is much appreciated. While Pirelli DH's are in the future it is still going to be awhile before I make that jump. I have been running square 275/35/18 NT01's but now that I have the room I want to increase the width but stay with a fairly comparable level of tire. NT01 comes in pretty tall at 305/35 so I'm going to try the Yokohama ADVAN A052 in 295/30/18 when they come back in stock. They reportedly run wide so more like a 305 width. Since it's going to be multiple sets I would like these wheels to be my endgame fitment & be able to transition well from here up the ladder eventually to the DH's.

Do you run any spacers with the Titan 7's?

Thanks!

I do run a 3mm spacer in front, but with 305 DH, it's mainly due to trying to keep away from the supercharger intake (which sin't working so well......). If I don't have a supercharger, I believe that I could run a 305 DH without the spacer and still be ok with the spring perch given how I've setup my JRZ. But as I recall, I needed the 3mm spacer for the R1S because it was just too close. JRZ said you need at least 2-3mm between the tire/rim and the spring perch due to flex.

Regarding my JRZ setup, I went with a 5" spring and removed the helper spring so I could raise the spring perch high enough to get it out of the way of the tires. And I run max camber----as much as the Vorshlag allow.

[ApexWheels]

Originally Posted by jktx

The info is much appreciated. While Pirelli DH's are in the future it is still going to be awhile before I make that jump. I have been running square 275/35/18 NT01's but now that I have the room I want to increase the width but stay with a fairly comparable level of tire. NT01 comes in pretty tall at 305/35 so I'm going to try the Yokohama ADVAN A052 in 295/30/18 when they come back in stock. They reportedly run wide so more like a 305 width. Since it's going to be multiple sets I would like these wheels to be my endgame fitment & be able to transition well from here up the ladder eventually to the DH's.

Do you run any spacers with the Titan 7's?

Thanks!

Dogbone gave some great feedback. Although mounting 305 track/race compounds on an 18x11" square wheel configuration is marginally superior in the right drivers hands, it will take some trial and error up front to prevent contact under suspension compression. You are simply running out of real estate under the front fenders. Running a short 5" linear spring to get the lower spring perch as high as possible (so it sits above the tire rather than next to it) without sabotaging your ride height in combination with a healthy amount of negative camber is necessary for starters, and although this setup is feasible, an 18x10.5" ET22 provides enough sidewall support for 295 and 305 tires and is much easier to work with.

We specifically lowered our 10.5" wheel offsets to ET22 (from ET27) to ensure E9X M3 owners had the opportunity to run a 10.5" rotatable square setup without the need for spacers. If you are using 10.5" wheels with a higher offset, strong chance you will need small spacers to clear your struts. Our two newer wheel designs (SM-10 & FL-5) are available in these specifications. 18x10.5" is also a very popular rear wheel specification for enthusiast running staggered fitments, and the lower ET22 offset results in a more flush fitment (again, so spacers aren't needed).

18x10.5" ET22 with 295/30-18 Yokohama A052's is the perfect upgrade from the common 18x10" ET25 with 275/35-18 NT01 setup. Once you have plateaued on the Yokos, you can upgrade to a wider compound without worrying about spending more on wheels.

- Ryan

[dparm]

Originally Posted by jktx

Plan to move up to a 305 square setup shortly - would an 18" x 11" wheel work or is 10.5" a safer choice? JRZ Pro, will go to a 5" spring & will run as much camber as needed. Would like to run the same offsets - will run spacers if necessary as well.

As Apex and others have said, for track usage I would be looking at what the tire manufacturer suggests. For those scrubs that someone suggested, they typically specify one ideal width.

FWIW, I run 315s on 18x11 (on my Corvette).

[ApexWheels]

Originally Posted by dparm

As Apex and others have said, for track usage I would be looking at what the tire manufacturer suggests. For those scrubs that someone suggested, they typically specify one ideal width.

FWIW, I run 315s on 18x11 (on my Corvette).

I'll finally have some 18x12's & 18x13's for your Vette soon

- Ryan