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      11-20-2015, 01:15 PM   #23
dfjaws
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The E36 crash bolts work identically on a Z4M as they work on the E36 platform. You can just get those if you want. That being said, they are not legal for a 'street' class. Per the rules they must be prescribed by the manufacturer in order to be allowed and they are not prescribed by BMW. Scion/Toyota is an example of a manufacturer who prescribes them so they are allowed for the FRS crowd.
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      11-20-2015, 01:19 PM   #24
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Also, as a side note, there is no Street Touring class for the Z4M. We get to play in either BS or BSP. Bummer.
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      11-20-2015, 04:34 PM   #25
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Quote:
Originally Posted by F360C View Post
I agree with dc-wright on this... run at least a 255 with that 275 rear. These cars need way more tire up front for autox. 255 is good, 265 even better and square 275 is where the money is at. With that said I also found the 255/35/18 fit better then the 245 due to the height of the sidewall. Our cars can take more tire up front then most people think with out rubbing. The limiting factor I find with the front tire is the diameter of the tire.

Last autox of the season coming up for me this weekend!
What about when you put -2.5 camber? Will the 255 up front rub on the spring or spring perch?
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      11-20-2015, 05:45 PM   #26
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Quote:
Originally Posted by dfjaws View Post
The E36 crash bolts work identically on a Z4M as they work on the E36 platform. You can just get those if you want. That being said, they are not legal for a 'street' class. Per the rules they must be prescribed by the manufacturer in order to be allowed and they are not prescribed by BMW. Scion/Toyota is an example of a manufacturer who prescribes them so they are allowed for the FRS crowd.
This was my point when I stated "not available". The E36 bolts will fit but you can't use them legally for Street since they're not listed for the M.

It's just mind boggling that for Street class SCCA considers all Z4's from the 2.5 to the M equal, but doesn't allow the M in STR.

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What about when you put -2.5 camber? Will the 255 up front rub on the spring or spring perch?
Even with the 255s you should be able to get to -2.0 degrees with the camber shims. You'll have to keep an eye and the spacing between the inner tire sidewall and the strut body. Worst case you use a 5mm spacer to give added clearance if needed. If you install camber plates it's moot because the whole steering knuckle and strut move as one so the spacing between the tire and strut remain constant.
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Last edited by dc_wright; 11-20-2015 at 05:50 PM..
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      11-20-2015, 06:41 PM   #27
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Quote:
Originally Posted by dc_wright View Post
This was my point when I stated "not available". The E36 bolts will fit but you can't use them legally for Street since they're not listed for the M.

It's just mind boggling that for Street class SCCA considers all Z4's from the 2.5 to the M equal, but doesn't allow the M in STR.
Ahh, my bad. I misunderstood what you meant. We're on the same page.

I agree. I wish we had a ST class to play in. I'd like to see it go into STR or STU but oh well.
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      11-20-2015, 07:00 PM   #28
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Originally Posted by dfjaws View Post
Ahh, my bad. I misunderstood what you meant. We're on the same page.

I agree. I wish we had a ST class to play in. I'd like to see it go into STR or STU but oh well.
Write letters saying so. Ask for a proper classing in ST. State your case (using the 370z for example would be a good start).

https://www.crbscca.com/


Can't make a change unless you request it.

Honestly, it's one of the main reasons why I bought a 128i for a full tilt STX build. It's pretty fun too I guess
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      11-21-2015, 10:06 AM   #29
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Any thoughts on brake pads for autocross. I really like how the stock pads feel, it stops on a dime. I had Carbotech 1521's on my STi that I really liked for autocross. KNS Brakes sells them for the the E46 w/competition brake package. I am assuming that is the same as the Z4m Brake package. I don't see any reference to Carbotech in the Z4M community as of yet (I'm still new)
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      11-21-2015, 06:20 PM   #30
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I've used the Akebonos for autocross and they did fine. I'm currently running Performance Friction Z Rated pads and I'm fairly happy with them. They're not terribly dirty, they're well behaved for street driving (decent initial bite and no noise), they do fine for autoX, and have been Ok for light track days. I ran Hawk Street/Race pads for a bit as I was doing more track events, but they were hideously noisy and it was difficult to get them warm enough for good performance for autocross.
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      11-21-2015, 10:09 PM   #31
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Originally Posted by Kgolf31 View Post
Write letters saying so. Ask for a proper classing in ST. State your case (using the 370z for example would be a good start).

https://www.crbscca.com/


Can't make a change unless you request it.

Honestly, it's one of the main reasons why I bought a 128i for a full tilt STX build. It's pretty fun too I guess
Myself and a friend both did but I guess it wasn't enough
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      11-21-2015, 10:21 PM   #32
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Quote:
Originally Posted by Bossdog
Any thoughts on brake pads for autocross. I really like how the stock pads feel, it stops on a dime. I had Carbotech 1521's on my STi that I really liked for autocross. KNS Brakes sells them for the the E46 w/competition brake package. I am assuming that is the same as the Z4m Brake package. I don't see any reference to Carbotech in the Z4M community as of yet (I'm still new)
Ferado DS2500s

I will no longer support HP+. It's an awful pad
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