Street Tire Class 2013

JamesShort · **Posted:** Tue Jun 04, 2013 8:41 pm

Aaron Buckley wrote:

IIRC, the R32 is not turbocharged. - AB

Yup, Bill has a Golf R.

Bill Aycock · **Joined:** Wed Sep 26, 2012 1:55 pm **Posts:** 117

Thanks to all for their input. It is very helpful in trying to figure out priorities, especially when being temped by mods which are likely wasted in the light of my lack of experience. I would also like to say that being a part of this club for the last 8 months has been an absolute blast. Everyone has been very welcoming and helpful, so kudos to you all. It a good bunch of folks!

I have tried to be patient on mods since purchasing this car, and really have only done one mod thus far, which is the one everyone says should be done first: tires (Michelin Pilot Super Sports) I immediately saw results in terms of times and standings position at my first event on them (Fayetteville). However, the absence of Chuck, Rodney, and Jordan didn't hurt either.

I take Shawn's point to heart about priorities. This being my first full season, my goal is to really just find my feet and see if I can be competitive. I took the advice of Matt McGrain at my first club meeting, to stay stock, get the feel for my car, and stick to the PAX classes. As for the car, this is not a dedicated autocross car. It's my daily commuter, plus daily fun car, plus autocross car, so I'm really trying to cover the spectrum. I want to be competitive at autocross, but i spend more time in this car in an every day sense. The ECU tune is really for shits and giggles, but, I don't want to do anything that would really serve to handicap me when an autocross comes around. I don't plan on being in a PAX class forever, especially with the uncertianty surrounding stock/street class for next year, so who knows.

I'd be curious to hear more about your opinion on tunes, James. I realize that they are not a silver bullet, but they do seem to offer some pretty good bang for your buck.

Aaron Buckley wrote:

IIRC, the R32 is not turbocharged. - AB

You remember correctly, however the current iteration R is a turbocharged 4-banger.(and hence just referred to as an "R" and not an "R32" I guess people thought "R20" didn't have the same ring to it.

JamesShort wrote:

BIll, electronic boost modifications are not allowed in ST* anyway. I assume your 'ecu mod' would change boost levels and therefore you'd have to go to RTDSP or DSP.

Are you telling me that none of all those S-2000s have a tune??

More to the point, quoting 2013 SCCA Solo Rulebook 14.10.F - Engine and Drivetrain

Quote:

The engine management system parameter and operation may be modified only via the methods listed below. These allowance also apply to forced induction cars, except that no changes to standard boost levels, intercoolers, or boost controls are permitted. Boost changes indirectly resulting from allowed modifications are permissible but directly altering or modifying the boost or turbo controls, either mechanically or electronically is strictly prohibited. 1. Reprogrammed ECU/PCM (via hardware or software_ may be used in the standard housing.

Does this mean if the ECU reprogramming specifically addresses boost levels, then that change to the engine management system is prohibited, but if the software changes other aspects of the tune, and only incidentally increases boost, then that change is permissible? It seems hard to believe that you would actually have to compare the code of one tune next to another to determine if boost levels are directly vs. indirectly addressed, but then again, I'm no tuner.
If nothing else, there appears to be a valid argument to be made here, that a tune is not prohibited in ST per se.

JamesShort · **Posted:** Tue Jun 04, 2013 9:04 pm

The only S2000 that runs with THSCC regularly that is tuned is Jeremy's (the one I drive). Hondata changes VTAK engagement point, fuel trim, timing, has launch control, redline etc. This is all permitted under ST* rules.

Electronic boost control/changes are specifically prohibited. If however, legal tuning/mods result in elevated boost levels (as read by a boost gauge for instance) then that is fine. For instance STU Subaru STIs run a legal downpipe and due to the flow geometry and lack of modification to the waste gate control yadda yadda, the turbo system exhibts boost creep in low gears and boost higher than factory specs even with an STU legal tune. However, these tunes are such that they can run really lean under load in higher gears so you shouldn't run them for daily driving.

Anyway, it's well know that Stage 1/2 tunes do directly up the boost levels (quite significantly as VW is crazy conservative with the factory ECU tuning) so those aren't going to be ST* legal. I think my ex-coworker who had a second generation 2.0T GTI said that a stage 1 tune made it go from 180whp to 250whp or something nuts (mostly due to boost). The S2000 might get 4whp with the Hondata tune for comparison

.

Jeremy Ellison · **Joined:** Fri May 13, 2011 5:01 pm **Posts:** 186

Minor correction, Launch Control is not ST legal either. However, a 2 step rev limiter (one limit with the clutch in and speed of 0 and another with the clutch out) is. The difference is that most Launch Control configurations use traction control or ABS to detect wheel slip and manage throttle/rev limit accordingly.

Zach Hill · **Posted:** Wed Jun 05, 2013 10:28 am

In my opinion, speaking in a general sense, I think the ST classes offer the best compromise for a daily driven fun car, or as some call it the "daily race car." Street Touring allows for fun & easy mods like intake, exhaust, and suspension, which to me are the most common, easy, and best bang-for-buck on a daily driven car. Plus being able to drive to the event on your competition street tires ain't bad either, not to mention not having to worry about being at a disadvantage to someone who just spent $1500 on R-comps.

The monkey wrench comes because your car has forced induction, and therefore has restrictions with ECU modding since it will affect the turbo and could give huge power gains making it unfairly competitive in the class. If you're dead set on a tune for street driving purposes, I say go for it and accept that you'll be at a disadvantage at autocross and just have fun. But, if competition is more important to you, then I would go the route of Tires (sounds like that's already done) > Intake > Suspension (anti-roll bars > coilovers) > Exhaust, and run in STX. You might be surprised how much you'd enjoy these mods on the street as well. You may be outclassed at first once you enter the class (plus we have at least one fast driver running there), but having a high benchmark to shoot for makes a for more interesting competition, right?

JamesShort · **Posted:** Wed Jun 05, 2013 10:56 am

Jeremy Ellison wrote:

Minor correction, Launch Control is not ST legal either. However, a 2 step rev limiter (one limit with the clutch in and speed of 0 and another with the clutch out) is. The difference is that most Launch Control configurations use traction control or ABS to detect wheel slip and manage throttle/rev limit accordingly.

Derp, you are right. That's what I meant anyway....too bad I can't get any wheel spin even if I purposefully hold the revs at 4500 rpms

.

@Bill The Golf R comes with 26 lb 18x7.5" wheels and 225s, I bet you can find some 17x8 or 17x8.5 wheels and put some stiffer sidewall tires (Rivals/Star Specs) on them and see a big performance gain (stiff sidewall tires are important on strut based cars). The aftermarket wheels will probably be a lot lighter too.

Another important thing is going to be front camber. Unfortunately the Golf/GTI has similar style struts to the E46 where the strut slides into a clamp mount knuckle so use of camber bolts is out. The only way to get more front camber is with slotted strut towers (not sure if the GTI has some slots from the factory) or with camber plates which will require smaller diameter racing springs (ie you are getting coilovers at this point).

My next step with be sway bars and dampers. Start with a bigger rear adjustable bar only and see how the rear wheel lift is and when you get some new dampers, hopefully the increase in rear bump damping will slow the rear transitional response to manage the wheel lift. Coming from the WRX, I learned quickly that despite what many people think (namely that AWD cars in smack dab in the middle of the FWD -> RWD spectrum) that AWD cars are much closer to FWD cars than anything.

Next would be to optimize spring rates and maybe lower the car a bit (remember lowering a macstrut car too much can really botch the suspension geometry). At this point, given my comments about camber above, you should just consider going to a full coilover with camber plates.

Patrice Bousquet · **Posted:** Wed Jun 05, 2013 1:20 pm

Instead of a tune you might want to look at a piggyback box like the one TMC make.
Those will fit the regulation because they connect between the sensor and the ECU and are using OEM style connector.

2. Supplementary (“Piggyback”) ECU may be used subject to the
following restrictions:
a. Connects between the standard ECU/PCM and its wiring harness
only.
b. Must be plug-compatible with the standard ECU/PCM (no splices).
3. Electronic components may be installed in-line between an engine’s
sensors and ECU/PCM. These components may alter the
signal coming from the sensor in order to affect the ECU/PCM operation
of engine management system. Example: fuel controllers
that modify the signal coming from an airflow sensor.

I think a tune is better than a box but if you want to stay in ST the box will be the way to go.
I didn't do anything to Abarth engine yet, the only tune available for it are bench tune, meaning you need to send your ECU to be re-flash.
There are some working on an ODB download so maybe later on a tune will be available to download thru the ODB port but even
there it will be most likely not legal for ST.

Like other said do spring and swaybar first, this is what I have done to the Abarth.

Les Davis · **Joined:** Fri Aug 29, 2003 2:04 pm **Posts:** 2059

My advice? Just run your appropriate Street Mod class, screw silly SCCA rules and most importantly PAX (PAX SUX) and enjoy modifying you're car however you like. Boost is fun, more boost is more fun. If you have a turbocharged car and you are running stock boost level you are not having as much fun as you could be with your turbocharged car, run more boost, and have more fun.

JamesShort · **Posted:** Wed Jun 05, 2013 2:52 pm

Patrice Bousquet wrote:

Instead of a tune you might want to look at a piggyback box like the one TMC make.
Those will fit the regulation because they connect between the sensor and the ECU and are using OEM style connector.

2. Supplementary (“Piggyback”) ECU may be used subject to the
following restrictions:
a. Connects between the standard ECU/PCM and its wiring harness
only.
b. Must be plug-compatible with the standard ECU/PCM (no splices).
3. Electronic components may be installed in-line between an engine’s
sensors and ECU/PCM. These components may alter the
signal coming from the sensor in order to affect the ECU/PCM operation
of engine management system. Example: fuel controllers
that modify the signal coming from an airflow sensor.

I think a tune is better than a box but if you want to stay in ST the box will be the way to go.
I didn't do anything to Abarth engine yet, the only tune available for it are bench tune, meaning you need to send your ECU to be re-flash.
There are some working on an ODB download so maybe later on a tune will be available to download thru the ODB port but even
there it will be most likely not legal for ST.

Like other said do spring and swaybar first, this is what I have done to the Abarth.

Even a piggy back that affects boost levels via electronic 0s and 1s is no go in ST

. Just to be clear, ECM tuning IS legal in ST* whether it be a piggy back or direct flash. The main caveat is for force induction cars and directly/electronically altering boost levels via said tuning/piggy back signal modifications.

Patrice Bousquet · **Posted:** Wed Jun 05, 2013 6:13 pm

This is the important part then.

Boost changes indirectly resulting from allowed modifications are permissible
but directly altering or modifying the boost or turbo controls,
either mechanically or electronically, is strictly prohibited.

So on a turbo car almost any tune and box is not legal as I'm pretty sure they are all changing the boost level.

Steven Carter · **Posted:** Wed Jun 05, 2013 8:28 pm

No, that's not it. If you DIRECTLY, by mechanical or electrical means (ECU tuning boost parameters), raise the boost level then you are afoul of the rules. IIRC, the Subarus have an available divorced downpipe which as a side effect of the downpipe construction indirectlycauses boost levels to be higher than OEM. That effect is legal.

It seems very difficult to police the issue, however. That is why I moved from an STU to an STR vehicle. Well, that and the 2009 WRX is the black sheep of the WRX clan, apparently....

JamesShort · **Posted:** Wed Jun 05, 2013 10:01 pm

What Steven said. See my post 3 to 4 posts ago about Subarus and boost creep.

Bill Aycock · **Joined:** Wed Sep 26, 2012 1:55 pm **Posts:** 117

Lots of good stuff here!

Generally speaking, I am concentrating on raw times, as they are certainly a better gauge of whether or not i am improving, and its true, going against solid competition is a good motivator. I am, however, enjoying the PAX element of TIR as it seems to allow for a large number of competitors in different kinds of cars, and there are numerous good drivers in TIR setting a high standard.

Back to mods...

I had considered purchasing dedicated wheels and tires, but they weren't in the budget just yet, hence the Michelin PSSs which struck me as a good dual-use tire. As far as the tune goes, I might consider paying the extra $$ for program switching so that i can return to stock parameters for an autocross event, if the club is cool with that sort of thing. Apparently there are companies out there that will provide a custom tune that would not directly alter boost levels, however. How are these sorts of issues policed at the national level?

As to additional mods like coilovers, camber plates, and sway bars, they are all on my radar, but i think I will probably see how the new street class rules play out.

JamesShort · **Posted:** Thu Jun 06, 2013 1:37 pm

Bill Aycock wrote:

How are these sorts of issues policed at the national level?

If you suspect someone is cheating you protest them and they have to prove to you that their tune doesn't alter boost levels directly. All the STU Evo/STI folks know the tunes/tuners so well that they know who is legit or not since very few shops do STU tunes since most people buy ECU tuning software/interfaces specifically to increase boost.

And you definitely can reflash to stock at events to run DS. There are the witch hunters who say that flashing the ECU too many times can mess it up, but I think that number is probably so large that it's infeasible that it would ever materialize in a bricked ECU in anyone's lifetime.

If you are still figuring out DS or STX, I'd at bare minimum get the rear bar since it is stock/street legal and if the Golf R is like any other VW I've driven, it pushes like mad. Rear bars are generally super easy to install and not prohibitively expensive (probably less than $200 and you can DIY McMaster endlinks like a lot of us if the OEM ones are weak.

Steven Carter · **Posted:** Thu Jun 06, 2013 1:45 pm

....and recall that the M3 that won STU in 2013 was cammed, and no one protested. I think that says something. Not sure what exactly, but that was interesting to see.

THSCC Forums

Street Tire Class 2013

Who is online