226 replies to this topic

[Brandon]

Brandon comparison to a stock part for compliance is very common procedure without publishing specs. 

 

Then a rescinding of the published tech article would be in order as well as that's the defined limits of the parameters of the component. It's superfluous to remain in effect if the review will be a subjective analysis by the tech stewards.

 

This is the problem when proposals seemingly appear out of the blue (I'm thinking back to the offset bushings) - there isn't a full analysis of the extent to which other pieces need to be altered as well. The original bushing proposal didn't specify concentricity of the through-bolt holes nor whether they could be positively fastened into place in the UCA.

 

The submission, as noted in the latest Fastrack, does not indicate the canceling/removal of the spec sheet which is why I'm asking for clarification on whether the "comparison to a stock part" is how the rule will be enforced.

 

ETA - my reasons for being pedantic about this is an effort to ensure there's alternatives to merely "I think they're bad so I'm buying all new". Send them off to a rebuilder for a refresh and balancing (minimal variation between L/R) and as long as the graph "looks stock" we should be okay? That ambiguity is not confidence inspiring for someone potentially getting a DQ.

 

Publishing a graph of X would be helpful for everyone to ensure there's minimal risk of such an incident happening. Especially if there's a desire to put the genie of "parts optimization within published parameters" back into the bottle.

[Steve Scheifler]

As much as it might pain him to hear ,  I agree with Todd's responses to FC.  But I would like to be very clear on what is being proposed going forward because it may have gotten lost in all the other discussion.

 

We know that the shock specifications used by tech until now still allow considerable reshaping of the response curves, but they were designed to accommodate production variances and change due to normal use, and probably a good deal more.  Fans of a low-rebound approach (popular a decade before FC got involved) probably weren't deterred much.

 

Question 1: Will the rules clarification revise those specification boundaries in any way?  If yes, will they be published?

 

As I understand it: (Please correct me where I am mistaken)

• Whatever the exact dyno test specifications/limits, tech will also be empowered to do a visual comparison of the curve to those taken from numerous unmodified shocks and use their judgement to determine whether the shock is likely modified from original. (Arguably, this is not so different from visual inspection of any physical part to a stock one from Mazda)

• Tech will also have the latitude to conclude from visual inspection that although a shock fails against a particular specification that it is the result of wear or damage and requires no further action (or perhaps test the other shocks from that car depending on circumstances).

• If a shock technically passes the dyno test but there is reason to suspect it has been modified, tech has the option to issue a DQ, confiscate the shock and have it disassembled at a later date for confirmation.

Is that an accurate summation?

 

Question 2: Do the proposed changes allow tech to DQ a competitor for evidence that the shock has been "opened" even if there is no other evidence that it has been modified with respect to valving?

 

I have had a lot of shocks tested, using three different shops over the years.  Because I'm typically working on two or more cars at a time I have always sent in at least three full sets and as many as seven.  I never did get back at least 4 sets from one shop because after pulling out the best matched sets the rest were non-compliant and/or not worth keeping unless I had them overhauled.  Back then the new ones were reasonably consistent so I just ordered more of those, and had them tested.  Since then our "spec" shock has changed and from what I've seen they are less consistent even though still within the wide specifications allowed by the guidelines used in tech.

 

I mention this only because regardless of any rule and enforcement changes there will still be some value in having shocks tested and matched, and even choosing which side of the car gets which shock from a set.  It's not going to make a huge difference but it will remain one of those "top prep" items that the most meticulous among us will continue to do if for no other reason than we can.

 

I'm not sure that the SCCA is equipped for a flood of shock testing, but those looking to have their shocks dynoed over the winter, for whatever reason, might want to check with V2 Motorsports. They've seen a lot of both stock and modified SM shocks.

[BNaumann]

Call the shape of the graph "probable cause". I know you don't believe it but as Ralph said any modification that makes a difference will be plain as day. I'm sure a competitor would be given benefit of the doubt and if there was any contention there would have to be a tear down.

Publishing a spec is what caused the grey area in the first place. Along with the clarification that table should be removed from the GCR. I hope the people with the data do at least post a min/mean/max for your reference, but this should be info only and not added to the GCR. I believe Shaikh has already shown a similar sample in his videos.

With a new "limit", people are going to cheat again by changing the valve code to exploit the area in the tolerance band. I also feel that even if your shocks fall outside whatever sample the powers that be have amassed, your shocks should still be deemed legal if they have the correct unmodified components inside. This is why actual numbers should be reference only.

There is a reason the F-V curve is referred to in the industry as the "characteristic curve". The shape of that curve indicates the character of the shock. Actual numerical measurements are subject to many different variables.

If you did want to blueprint or sort this particular shock for this application, you would want to max compression and minimize high speed rebound within the tolerance band. As Shaikh has pointed out, these shocks are shit for this application, and if someone wanted to waste time and money doing that, there would be virtually no gain.

However, if you start changing the parts specification to change the character of the shock within that tolerance band, there are definitely gains to be had.

I actually agree with everything Shaikh says, understand his position and respect his right to present his well-written arguement to the CRB. But I believe his shocks have been illegal since day one.

Shocks should not be illegal because they fail a dyno test. The dyno test is only an easy indicator that something may be wrong.

[High Chair]

Damn... Just bolt on some new shocks and go race.. 99.9% of the drivers in SM couldn't tell the difference anyway and wouldn't go faster if you put fully adjustable shocks on the car. Except for Todd Lamb... He is my hero.

[MPR22]

 

     Todd, I get it, spec class, everyone has to deal with it........Then why do we still have cylinder heads with much more machine work than as they came from Mazda? ( personally thought we should have gone back to stock heads)If we all had the crappy ports and chambers, we ALL have to deal with that. Or pick through a pile of heads for a good one right?(like some will do with out of the box shocks.....).   

The variance in lap time with stock heads would have been +/- 1 second across the range of stock castings.  The variance on stock shocks is nearly non-existent as FC pointed out the system is out of whack because of the springs.  A pile of heads at $250 -$400, not to mention the labor and dyno time testing what head works would be extremely expensive to achieve the parity we have today.  @ $125 a piece if someone like Steve wants to dyno test and parts bin match shocks to gain less than a .1 a lap that's the nature of the beast in spec racing.   As Jamie pointed out a large portion of those racing never put the car at the limits to see the benefit of the matched shocks anyways.  

 

To show you how over sprung these cars are, go shave a set of SM7s.  That 2mm you shave off will make the car nearly un-drivable.    

[Steve Scheifler]

The variance in lap time with stock heads would have been +/- 1 second across the range of stock castings.  The variance on stock shocks is nearly non-existent as FC pointed out the system is out of whack because of the springs.  A pile of heads at $250 -$400, not to mention the labor and dyno time testing what head works would be extremely expensive to achieve the parity we have today.  @ $125 a piece if someone like Steve wants to dyno test and parts bin match shocks to gain less than a .1 a lap that's the nature of the beast in spec racing.   As Jamie pointed out a large portion of those racing never put the car at the limits to see the benefit of the matched shocks anyways.  

 

To show you how over sprung these cars are, go shave a set of SM7s.  That 2mm you shave off will make the car nearly un-drivable.    

 

Some that I have tested over the years were of questionable provenance, some were bought new by me but used for a season or more and being re-tested, and now I just plain don't trust Bilstein QC.  And I know that depending on the source, they may be returns already rejected by someone who buys extra and keeps the best.  Once you have the test results it would be pretty silly to not at least match them up into sets. 

 

BTW, your estimate of stock head variances is as far off as FC claims for shocks that still meet current specification limits, but your points are still valid and I fundamentally agree with them.

[MPR22]

Some that I have tested over the years were of questionable provenance, some were bought new by me but used for a season or more and being re-tested, and now I just plain don't trust Bilstein QC.  And I know that depending on the source, they may be returns already rejected by someone who buys extra and keeps the best.  Once you have the test results it would be pretty silly to not at least match them up into sets. 

 

BTW, your estimate of stock head variances is as far off as FC claims for shocks that still meet current specification limits, but your points are still valid and I fundamentally agree with them.

We saw 6hp in an NA 1.6 with horrible core shift.  I did use a bit of an outlier. 

[Steve Scheifler]

We saw 6hp in an NA 1.6 with horrible core shift.  I did use a bit of an outlier. 

 

 

A bit, and would not require a flow bench or dyno testing to weed that one out, but OK, your +/- 1 second is still a 2 second swing from worst to best. Show me even one track where 6 hp is worth 2 seconds in these cars.

[MPR22]

A bit, and would not require a flow bench or dyno testing to weed that one out, but OK, your +/- 1 second is still a 2 second swing from worst to best. Show me even one track where 6 hp is worth 2 seconds in these cars.

sorry, you are correct.  I meant total delta of 1 second.  

[MPR22]

A bit, and would not require a flow bench or dyno testing to weed that one out, but OK, your +/- 1 second is still a 2 second swing from worst to best. Show me even one track where 6 hp is worth 2 seconds in these cars.

Road america might be 1.4 because you couldn't hold the draft.  Road Atlanta might be .75, VIR .8.  Daytona could be the worst but i haven't ever driven a car 6 hp down there. 

[speedengineer]

My thoughts.

 

1)  The rule is (even currently) modified shocks are illegal.  Why yes, opening them up to make any changes...is ILLEGAL.

2)  As Ralph said, any stock shock will fall within their proposed tech reference curves.  So if you have a stock shock (aka LEGAL) you will be fine, no need to worry about it.  No need to compare it to any curves.
3)  Do NOT publish the tech reference curves.  Doing so will only provide information to potential cheaters so they know how much they can adjust their shock tuning by and still fly uder the tech radar and avoid a bilstein inspection.  If you have LEGAL shocks, again, you don't need to worry about it.
4)  If you want to dyno a bunch of legitimately stock ones and match them up, go for it.  


In my opinion, anyone who is finding any objection to these improved shock rules is likely someone who:
1)  Likes cheater shocks and shock rules loopholes so they can maintain their (perceived) competitive advantage over honest drivers.
2)  Doesn't comprehend the best interests of the class.
 

As mentioned by others, do remove the current shock force curves from the scca website as they will no longer be relevant.

[Steve Scheifler]

Road america might be 1.4 because you couldn't hold the draft.  Road Atlanta might be .75, VIR .8.  Daytona could be the worst but i haven't ever driven a car 6 hp down there. 

 

 

OK, we're getting closer.

 

If you were in a tight draft above ~ 90MPH then 6HP would not be enough to break it.  The problem, and any 1.6 owner already knows this, is that the car with an advantage below that pulls away enough to keep you from staying close enough until the benefits of the draft exceed the difference in power.  At a place like Daytona the draft is worth WAY more than 6HP through 5th gear.  So what's less obvious is that without the draft 6hp would have very little impact on terminal velocity between two cars running solo and probably less than you think for an "unassisted" full lap.  But if there are three cars and two of them are able to pull away from the other as they first hit the oval because he's down 6hp, then sure he loses a LOT of time, not so much the 6hp but from being left out of the draft.  The same applies to your other examples if to a lesser degree.

[MPR22]

OK, we're getting closer.

 

If you were in a tight draft above ~ 90MPH then 6HP would not be enough to break it.  The problem, and any 1.6 owner already knows this, is that the car with an advantage below that pulls away enough to keep you from staying close enough until the benefits of the draft exceed the difference in power.  At a place like Daytona the draft is worth WAY more than 6HP through 5th gear.  What's less obvious is that without the draft 6hp would have very little impact on terminal velocity between two cars running solo and probably less than you think for an "unassisted" full lap.  But if there are three cars and two of them are able to pull away from the other as they first hit the oval because he's down 6hp, then sure he loses a LOT of time, not so much the 6hp but from being left out of the draft.  The same applies to your other examples if to a lesser degree.

What you are describing is the difference between time trialing and racing.  The real world is we race.  I have been 6 hp down many times for various reasons, in a race 6 hp at the tracks mentioned is worth the numbers i quoted, have the data to prove it.  Nobody is pushing you when you are 6hp down so you are on your own.  

[Steve Scheifler]

What you are describing is the difference between time trialing and racing.  The real world is we race.  I have been 6 hp down many times for various reasons, in a race 6 hp at the tracks mentioned is worth the numbers i quoted, have the data to prove it.  Nobody is pushing you when you are 6hp down so you are on your own.  

 

No argument there, just making clear to the casual reader that in absolute terms 6 HP is not worth anywhere near that much on it's own, and that you are in effect even by your last statements comparing draft laps vs solo.  That isn't HP alone and it is important to understand that there is a difference.  I have no qualms with your basic point.

[Brandon]

In my opinion, anyone who is finding any objection to these improved shock rules is likely someone who:

1)  Likes cheater shocks and shock rules loopholes so they can maintain their (perceived) competitive advantage over honest drivers.
2)  Doesn't comprehend the best interests of the class.
 

As mentioned by others, do remove the current shock force curves from the scca website as they will no longer be relevant.

 

Your generalizations aren't fair as it ignores other aspects of compliance that aren't being addressed with the single addition of the suggested rule.

 

We've had nearly 7 years of the "shock specifications" posted as part of that tech bulletin and unfortunately its publishing did not incorporate a mechanism within the ruleset to ensure enforcement in variation of those values. It was this omission which enabled the 2014 Runoffs result irrespective of what was actually done to those heads.

 

Knowing there are non-compliant components out there means it becomes a verification issue for the competitor. Absent something to test against, or a process which competitors can ensure they're compliant, you're at risk with products you did not directly order from Mazda and unbox yourself. And that doesn't even get to the specifics of the identified QC variations with the manufacturer. You're left with ordering whatever number of shocks to dyno and then match (parts binning) if you even have a dyno to test with.

Which was one of the major reasons for NOT returning to stock heads after 2014 Runoffs because of quality issues with the castings. Monied competitors would be buying multiple heads and building from the best ones. This was another supporting reason for permitting the 1.6s to modify their exhaust headers as the qualify of the welds at the flange & collector were poor and random.

 

I agree the removal of the tech bulletin should be done in conjunction with the implementation of the rule, but absent a process or accommodation for already installed shocks competitors will still be questionably in terms of compliance until they fork over the $600 (uninstalled mind you - which was another supporting reason for PERMITTING the UCA slot; cost & skill/capability to correct otherwise) and replace whatever it is they have.

 

I'm willing to do that myself as I've got two sets of shocks which I'm unaware of their provenance however I shouldn't have to if there's a method of ensuring compliance (posting a curve).

[Bench Racer]

Define opening please.........

Happily, opening, an aperture or gap, especially one allowing access.

 

Tamperproof seal, surly Bilstein/Mazda could implement. As Koni did for the SCCA Solo Spec class.

 

KONI Sport shocks and struts were selected for the SCCA Solo Spec Coupe class due to their wide range of user adjustability and robust design. The dampers are dyno-tested to ensure equal performance prior to shipping. An all-weather, tamperproof seal is installed by the manufacturer to comply with the class rules.

[BNaumann]

Happily, opening, an aperture or gap, especially one allowing access.

Tamperproof seal, surly Bilstein/Mazda could implement. As Koni did for the SCCA Solo Spec class.

KONI Sport shocks and struts were selected for the SCCA Solo Spec Coupe class due to their wide range of user adjustability and robust design. The dampers are dyno-tested to ensure equal performance prior to shipping. An all-weather, tamperproof seal is installed by the manufacturer to comply with the class rules.

Same as the bump stops, you are not going to make my current out-of-the-box stock shocks illegal by requiring this seal.

If you're going to make every single competitor buy new shocks, you might as well make them something that doesn't suck as Shaikh recommended.

[Alberto]

Don't forget that the oil used in shocks also affects their performance.  Also, the oil wears out and needs to be maintained - either via a shock rebuild or new shocks.  I kinda wish we could easily change shock oils each season so that performance stays consistent - and so the internals last longer.

 

It seems kind of wasteful to have to buy new shocks when they can be rebuilt.

[Todd Lamb]

Bromance!

Damn... Just bolt on some new shocks and go race.. 99.9% of the drivers in SM couldn't tell the difference anyway and wouldn't go faster if you put fully adjustable shocks on the car. Except for Todd Lamb... He is my hero.

[Bench Racer]

Don't forget that the oil used in shocks also affects their performance.  Also, the oil wears out and needs to be maintained - either via a shock rebuild or new shocks.  I kinda wish we could easily change shock oils each season so that performance stays consistent - and so the internals last longer.

 

It seems kind of wasteful to have to buy new shocks when they can be rebuilt.

Ok, what are the cost per shock to maintain to a level you desire? What is the frequency you'll do the rework/up date?

A new shock is $132.00.