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greg f

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I am confused by some verbage in the latest rules I have downloaded. Section 14.2 states " All shocks may not have more than two external adjustments. Remote reservoir shocks are not permitted. Threaded body shocks similar to the MO3O package are allowed on the front only."

Later the rule states that only Bilstein or Koni shocks of a particular part number(s) are eligible to be used. Neither of these shock models have two external adjusters, in fact the Bilstein is non-adjustable. None of them are threaded body replacement struts either. Why does the first paragraph of this rule exist if you have to use these specific shocks? Is it permissible to modify either brand of damper to be a threaded body damper ( front, similar to M030) with two external adjusters? Greg Fordahl

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That is an example of some rules upgrades we made, but never fixed the wording.


Basiclly we spec the shocks. Either pretty common Koni yellows or Bilsteins.


When we first started in 2002 the first part of rule was in place. Later in consulation with Chris Cervelli figured $5000 in shocks was not really in the best interestes of low cost class. This spec'ed out the two shocks. We just never took out the old wording. At one time it was assume that all top level shocks would have more adjustments and remote reserviors. .


The intent however is restict drivers to simple off-the-shelf street type shocks rather than allow the expense of proper race dampers. This is case of field goint .5 sec faster, spending $3000 more per car not improving the racing any. "Slip over collars" are legal to be able to install 2.5" racing springs in front. So one should never need to thread any shock body.

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So you all will be revising this rule then to make it reflect the intent? My only problem with the Koni yellow's is the frequent replacement required for the front units. Maybe our tracks are just much rougher up here but they will frequently squash the foot valve and quit adjusting. I can send these shocks to several places that would convert them to better, ( more $) valving and even make them double adjustable ( more $ again). Maybe the first paragraph should state that the two choices are to be unmodified versions of the off the shelf shocks.

My JRZ's were $1800 when purchased new 4 years ago. They are owner servicable and are the correct length for a lowered racecar. All in all a good investment for me. I still run used factory swaybars from an M030 924S. I can appreciate the need for a low cost Porsche class, ( wow, that just sounds wrong!) so I support what is happening around the country with these cars. I also know I do not want to step in the hole that the Spec Miata guys are in now. Since they all have the same suspension they instead spend their money on engines. This has created a have/ have not race class on the verge of going national. (The great thing about a 944 engine is that the intake system is a very effective flow restrictor that regulates the engines output.) Greg F

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Greg, I think you have a good idea there. Thanks for reading the rules and providing knowledgeable input. Any other glitches you've found?


"Maybe the first paragraph should state that the two choices are to be unmodified versions of the off the shelf shocks."


The "threaded body" for us is actually a slip over collar that allows ride height adjustment for the smaller diameter, shorter springs. We need to include this in the verbage.


Joe P. , can we clean that rule up and state it as simply and clearly as possible? How about if we state:


"Shocks must be either the original factory installed shocks or the following models and part numbers in an unmodified, off the shelf state."

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I don't make the rules. Just Follow them buddy!


Really the rules are decided between Steve and you being series directors and all. I will gladly publish and updates.


I agree that we can clean-up the wording. When we put this wording in place a couple years ago I asked about modified shocks. I guess right now it is covered under the "you can't do it if it does not say" rule. However a clarification would be helpfull.


There is one potential issue. It is probably easy to detect if the number of adjustments has been increased. Probably not so easy to tell if the internal valving has be adjusted. So potentialy we have no way of checking the valving and therefore can't enforce a "stock valving" rule.



That said the changes as proposed may still better than what we have now.



When it comes to cost and Koni durability. These off the shelf units can be had for $161ea front and $115ea rear. So a completely new set runs $552. Not chump change, but the $1800 JRZ's buys 3.25 sets of koni's.


Replacement in the rear is snap and the front is not hard especially with 2.5" springs. So... still the better value. Plus there are the bilsteins if you don't like the koni's.


With respect to the 944 intake. Yep... that was one nice thing about a 944-spec class. Because it is so hard to make more power from these motors is becomes a good spec type class. Junkyard vs built motors = same power. A 951 spec class would be blast, but near impossible to control hp due to the ease of increasing it.

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I don't have the full wording of the rules, but based on what I read here, there does seem to be a grey area. Both Koni/Truechoice and Bilstein will revalve the "spec" shocks to whatever you want. Truechoice can also convert the "spec" Koni to a double-adjustable. Would all of those be considered illegal by word of the rules? IE, does a rebuild/revalve essentially change the shock's part number for rules purposes?



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Sam, I believe the idea was to have CHEAP, EQUAL, shocks.

I would want that to mean unmodified, off the shelf, not re-valved, "just bolt them on" shocks.

The current wording for that rule leaves room for interpretation as to "tuning." Re-valving can be seen as tuning, just like the airflow meter.

If we can keep guys from spending more money on things like custom valving of shocks for different tracks, that would be great!

Thanks for helping to find problem areas with the current rules.


I, for one, would like to see the adjusting of cars limited to:

1. adjusting off the shelf Koni's. (OEM and Bilstein's aren't adjustable)

2. adjusting sway bars.

3. adjusting alignment.

4. adjusting tire pressures.


Other than that, just jump in and drive a car as equal as the guy's next to you on the grid.

But, I tend to be more conservative with respect to the rules. Hell, if I was a rich guy, I'd have a couple sets of headers and I wouldn't spare the bucks for labor to switch them for each track. But that would be the wrong attitude for a spec class. It's totally legal right now, though.

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