E36 rear LCAs

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TXBDan
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E36 rear LCAs

Post by TXBDan » Wed Jul 13, 2016 2:50 pm

Hi all, I needed more rear camber so bought Turner adjustable LCAs that use the factory rubber inner bushing.

I'm already taking a point (due to camber plates) for:
Non-Factory Trim/modified suspension components which enable alignment settings beyond Factory Trim capability (does not apply to coil springs, leaf springs, or torsion bars); note - additional points may need to be taken for specific non-Factory Trim suspension components if listed elsewhere in this section
Assume I must also take a point for:
Non-Factory Trim/Modified Control Arms or Non-Factory Trim/Modified Trailing or Camber Arms of different dimensions than Factory Trim
Right? These arms can be within the range of factory adjustment, but could also be a little longer dimensionally... Or does this rule only speak to non adjustable things of different dimension?

Thanks
Dan Durusky
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Re: E36 rear LCAs

Post by offcamber09 » Sat Jul 30, 2016 10:58 pm

Dan, sorry no one responded sooner. Yes you will have to take the second point for the Turner rear arms.
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Re: E36 rear LCAs

Post by joncowen » Mon Aug 01, 2016 9:56 am

I don't agree. The arms he's referring to replace the stock arms, and maintain the same geometry, same mounting points, same adjustment. They are simply stronger and easier to adjust. The factory ones bend when you put on sticky tires. The factory ones use eccentric bolts for adjustment, which freeze up and sometimes slip. Yes, they have more range of adjustment (length of the arm), but the stock ones have more than you should need, unless your car is bent, or you are into stance.

So, in my opinion, they are the same dimension as stock, and don't qualify for the point.

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Re: E36 rear LCAs

Post by blindsidefive0 » Tue Aug 02, 2016 12:46 pm

Dan and I spoke about this earlier this season, and I agree with Jon on this one.
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Re: E36 rear LCAs

Post by FredK » Tue Aug 02, 2016 11:08 pm

Probably can pull 1.9Gs like dis:

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Re: E36 rear LCAs

Post by offcamber09 » Wed Aug 03, 2016 10:00 am

The range of camber adjustment with the Turner arms far exceeds that of the stock arms. That is why I classified it as a 1 point hit. If you have camber plates and are taking the point for that- then you are ok:
"Non-Factory Trim/modified suspension components which enable alignment settings
beyond Factory Trim capability (does not apply to
coil springs, leaf springs, or torsion
bars); note -additional points may need to be taken for specific non-
Factory Trim suspension components if listed elsewhere in this section
"

Or is it?

"Non-Factory Trim/Modified Control Arms or Non-
Factory Trim/Modified Trailing or Camber Arms of different dimensions than Factory Trim
"

The Turner arms are certainly being used in a longer dimension than the stock arm.
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Re: E36 rear LCAs

Post by joncowen » Wed Aug 03, 2016 11:21 am

Some race classes allow only the stock arms, and most people reinforce them with steel to prevent them from bending, if allowed. To my knowledge, they have no trouble getting plenty of rear camber with the stock arms. I used to run stock arms (way back), and i also had no trouble getting more than enough camber in the rear. So, in my case, they aren't being used in a longer than stock configuration.

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Re: E36 rear LCAs

Post by paultg » Thu Aug 04, 2016 2:50 am

In my opinion you have to take the point. You can't negate the point because you aren't using the full range of adjustment or the full length on the non-factory part. - Paul G.
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Re: E36 rear LCAs

Post by wizzman » Thu Aug 04, 2016 9:13 am

Its not about what portion of the adjustable range you need its about what the part permits and if that is beyond what is possible with the OEM part it is replacing.

Paging Chief Steward Derek...
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Re: E36 rear LCAs

Post by jlwhorf » Thu Aug 04, 2016 9:24 am

The way I see it is:

The Turner and the factory arms give the desired camber setting with out being at max adjustment.

But

If the max adjustment of the Turner arm is greater than the max adjustment of the stock arm, a point should be taken.
If the max adjustment of the Tuner arm is not greater than the stock arm, no point should be assessed.

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Re: E36 rear LCAs

Post by TXBDan » Thu Aug 11, 2016 3:03 pm

First, thanks for all the input.

Second, I apologize for bringing this up in public as it could impact other people's builds and I'm sure they'd prefer to remain blissfully ignorant. (I would :P)

Third, how do we wrap this up? I guess I'll email Derek again for the final word and ask him to post here. My gut feel is that these are a point, but I've been abused by the SCCA for some years.
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Re: E36 rear LCAs

Post by Dtangard » Wed Aug 17, 2016 9:01 pm

Dan,

In this case, you do not have to take the second control arm point. The control arm point was not intended for this particular modification.

The team of stewards agree the wording needs to be improved for next season.

Ill quote Nick Fontana on the history behind the rule.
"The history on the control arm rule is that it was implemented when we deleted the 3-point line item for changing suspension mounting points - it was split up into other line items and done away with. The control arm point was intended to cover things like upgrading a 325i to e46 M3 control arms which changes more than just alignment. There are also plenty of modifications to rear trailing arms meant to change the geometry to increase rear traction. However, for modifications where the only meaningful benefit is alignment adjustment, the point was never intended to apply."
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Re: E36 rear LCAs (Update 3/24/17)

Post by Dtangard » Fri Mar 24, 2017 7:01 pm

Over the offseason, I wrote a rule change proposal to clarify the control arm rule to specifically allow the aftermarket E36 rear lower control arm to not take a point. When it came to a vote, the BOD reversed our previous ruling. Aftermarket E36 control arms will now cost you one point for "Non-Factory Trim/Modified Control Arms or Non-Factory Trim/Modified Trailing or Camber Arms of different dimensions than Factory Trim." If you already take an alignment point, you will still need to take the control arm point.

Since it is well documented that this is a weak spot on E36 chassis BMWs, we will allow competitors to reinforce the factory rear lower control arms as a zero point modification. If you want to purchase reinforced arms, BImmerworld sells them here: http://www.bimmerworld.com/Suspension-S ... swodaYABHg
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