Autocross Class for SS/TC with the GM Upgrade
 

With the new GM turbo upgrade or stage kit, would this make the car fall into DSP or SM. Thanks.

More power doesn't necessarily help. You need to be able to put that power to the ground. I would suggest if you're going to do some mods, lighter wider wheels, Sticky rubber and good suspension.

does GM upgrade modify boost?

Yes.

I'm not sure what is all changed with the stage kit - what all comes with it? The parts you change out will determine what class you get put into.

I'm not certain, but GM Stage 1 may only put you into STX since it's basically just a tune and sensor change...

DSP, same class I'm in, but you could move up to SMF if you wanted... It's a 'sensor' mod and a computer reflash, both legal within SP rules -- you're not modifying the turbo, you're changing the computer settings that handle airflow, spark timing and fuel....

I know I won't move to SM -- way too much money.

Scott

Oops, you can also run in STX if you want. I run in STX (a street tire class) in the winter to save $$$ on Hoosier slicks.

Scott

Alright thanks.

I'm just trying to figure what I should do first. I will be doing autocross and track days and I just need to balance everything out. Tires are probably number 1 and I know the GM kit will pay off a lot more on the road course rather than in autocross.

I would stay in stock and run better tires.

This. The TC already has enough power to easily over-power the front tires on tight courses like you see in Auto-X. You'll spend the entire time trying to limit excessive wheelspin and throttle-induced understeer. For road course racing I could see an upgrade being highly useful (I'm sure Venom09 will clean up next season), but for Auto-X I'd agree on wider, stickier rubber.

I personally can't wait to see someone fender roll one of these things, throw on 255 R-Comps, and get a tune... Imagine the cars one of those could destroy on a big road course.

You can now modify boost in ST classes?
I remember those Evos cant touch their boost back in my STU days...

You're right. SCCA Rules state in 14.10 F:

Is Stage 1 really changing stock boost levels, though? The car can achieve 22psi of boost stock, it's just rare that the PCM ever calls for it. So by simply fixing the boost at the stock maximum (which as far as I know, Stage 1 does), can you really consider it increased?

I guess this falls under modifying the boost controls, though.

Ya.. it's never clear to me...
You can modify ECU timing/fuel but no boost.. however
Boost changes indirectly from exhaust/instake are allowed....

But how do you tell one from the other? :confused:
(how do you catch those that cheat?)

Don't get confused by the words, you aren't 'modifying' boost -- by any means described in the reguations. You have replaced two sensors (OK) and modified the computer (also OK) -- you haven't done anything to the turbo -- you didn't install a boost controller, you didn't fiddle with the waste gate settings, you haven't added a bigger turbo or a second turbo -- you haven't modifed the boost.

Everything done by the GMS1 is within the rules.

Won't apply to stock. But DSP, STX, and SMF are all OK.

Scott

One more comment: if you just change the part you've made bold, you have the answer.

The engine management system parameters and operation may
be modified only via the methods listed below. Any and all
modifications must meet or exceed the applicable EPA tailpipe
emissions standards for the year, make, and model of the car.
These allowances 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.

Scott

but I remember cars like Evo... you can fool the ECU (via piggyback) to let it hold at
higher boost longer... (modifying boost via ECU...) or I'm guessing simply modify the ECU
to change the max and duration of the boost level is also possible....??

Wouldnt boost change via ECU fall under... altering/modifying boost electronically...?

My interpretation is that GMS1 is most definitely NOT allowed in stock. You are electronically changing boost controls first of all, second of all you are changing parts.

Yes, but you're not changing the factory boost controls to allow higher than factory boost - you're merely locking in the maximum STOCK boost allowable.

ya.. thats altering boost electronically... :lol:

i guess we can post on sccaforums to get a clearer explanation... :)

how would they know...there is no way to visably tell the diff.

A lot of autocross groups use the honor system. They leave it up to you to say/reveal what mods/upgrades you've done to your car. I CAN tell you this. If one of my fellow competitors started beating me I would be more than inclined..(and allowed) to ask him to take a look at his engine bay. Those nice new sensors stick out like sore thumbs when you compare them to the old ones. I would raise that flag immediately.

If he/she tried to get away with 'cheating' then there is no room for someone like that in most autocross groups.

Maven's absolutely right -- dead on the money, the GMS1 is definitely outside the Stock Class rules.

Classes aren't an 'I'll pick one' kind of deal. Almost the only exception would be something like DSP to STX -- and there are things you can do in STX that you can't do in DSP, and vice versa. My Cobalt SS just happens to meet both rulesets. Do I really want to run in STX? No, I don't, but the cost of slicks is high ($1300) and I need to save that money for the next Nationals. I can also make every effort to become a better driver with the crappy traction from STX approved tires -- even the best STX tires really SUCK compared to Hoosier slicks. I've been out once in STX -- I placed 3rd out of 9 STX cars -- not great, but I was also on very, very used Falken Azenis that I could spin under power at will -- even before the GMS1. Do I think I could be 1st in STX locally, possibly, but it still not as much fun as slicks!

Let me give you another example about the rules: I used to have a Saturn Redline that I ran in D Stock, I upgraded to a GMS1 for my Saturn -- only new injectors and a reflash -- presto, I was in DSP, if I had gone to the Stage II -- a smaller pulley -- I would have had to race in SM.

Since I couldn't get racing springs for my Saturn, I used 'lowering' springs with NASCAR-style 'spring rubbers' to stiffen the suspension. The 'spring rubbers' were questioned by an inspector at a National Tour Event tech inspection -- but after discussing with some others, he let it go that once. I read the rules again, spoke with my local SCCA rules guy (who agreed with me -- and said so in writing), and petitioned SCCA for a ruling based on how I read the rules -- they agreed -- so I was able to use the 'spring rubbers'. Had I waited til a Nationals, I'd have been protested.

You've got to read the rules!

Look, if you're driving kind of OK, then a better car probably means a better finish. If you're a great driver, you can probably finish well even in a piece of crap car. If you make the car as good as possible, within the rules, and you 'sort it out', then you have the opportunity to become a better driver -- and a great driver with a great car is unbeatable!

When I was setting-up my Cobalt, I asked lots of people (including many national champions -- FWD, AWD, and RWD) lots of questions -- one example, I asked about springs and sways. Most SCCA autocrossers said go with about 500-750 lb front springs and 600-1000 lb rear springs and don't add more rear swaybar. The Cobalt Time Attack crew said 450 lb springs front and rear and OTTP killer swaybar in the rear. Completely different approaches -- BTW, how you drive makes a difference in setup as well as the parts. But the 'real' race cars are hundreds of pounds lighter than a stock Cobalt; the racers use very expensive, completely custom axles; custom shocks & coilovers; mounted at different locations; different - adjustable springs; custom brakes; different gearing; etc.; etc.; etc.. Is it really a direct comparison -- no, it isn't! It makes for a good start-point and it is experience that most of us probably don't have -- so learn from it. Was I happy with my 550 fronts/650 rears and no extra sways at the Nationals? Yes, was. Was it the best solution, I'm not so sure. And for STX I'm running 360 fronts/250 rears with an extra sway -- just trying something different -- and I've run with stock suspentionin the past too. I'm thinking that I'm going to try disconnecting the front sway --- with the stiffest springs --- and give that a try too. You need to know where your going and make decisions based on what is allowed.

Bottom line, you need to make a decision, based on the rules (and your wallet), and plan your purchases and mods to meet those rules. I found out in Stock (and in DSP), if you don't do EVERYTHING the rules allow, you won't be competitive at the National level. If you do EVERYTHING, then you've got a chance -- it becomes more driver, less car, assuming that the parts you could use are available -- and just so you know, there's no where near as many Cobalt racing parts as you can find pretty easily for a BMW, VW, STi, Civic, Audi -- you get the picture. We're at a disadvantage from the beginning. The SS is pretty darned good, but it's not at the same level as any of the other cars I mentioned.

And for those who think that no one will notice that you're running a GMS1 in Stock, don't kid yourself, you're probably right at the local level and probably even at National Tour Events, but if you ever get to a Nationals, you should assume that some competitor knows about Stage Kit and is prepared to protest.

You wouldn't believe all the protests that came out of this year's Nationals. One guy said it right; 'If you're an also ran, nobody cares, but if you're placing, or, god forbid, in the top three, you can guarantee that you'll be protested.'

Once more, our flash doesn't 'control' the boost, it changes air and fuel flow. If those changes 'incidentally' cause the boost to rise under certain circumstantes, then it's OK.

One of the things you'll need to do, 'if' you plan to compete seriously in anything (but it applies to SCCA or NASA too), you need to get the rule book, every year (this is required by SCCA -- if you compete at any national levels - you have to show them your rule book at registration), read the rule book, read every word very, very closely, read other chapters (you'd be amazed at how the rules relate), and completely understand what it says. If you don't, or can't do this, you'll have a rough time competing.

Scott

As I read it GMS1 would not be allowed due to the fact it modifies boost, not necessarily the boost level since it can reach 22psi stock but modifies how the boost comes on which is modifying boost IMO. So, there for not being allowed in STX. But it's really confusing and could be read either way I think.

Not that more power would benefit us much.

So SMF DSP STX? What's the final anwser for a GMS1 SS/TC?

I think this has been pretty well covered -- No for DS, Yes for DSP, or SM (and you can be on DOT race rubber), or STX with street rubber. I will point out that I routinely race in DSP and STX, I used to race in DS -- to include at many SCCA National Tour Events and the SCCA US Nationals.

Everyone has lots of 'opinions' about this, you might think about giving more credance to those very few of us who regularly autocross race -- people who have cars that have successfully been through many tech inspections many times. I have the GMS1 on my car -- in DSP. Over the past several years, I have only seen two other Cobalts at the events I've run -- both in DS -- at National Tours or the Nationals.

There's lots of opportunities for autocross participation for Cobalts, but there aren't many participants -- how does the saying go, 'heap big smoke, but no fire'.

However, here are the 2010 SCCA Rules: http://www.scca.com/documents/Solo_R...inal_draft.pdf

and: http://www.scca.com/documents/Solo_R...inal_draft.pdf

Be sure to read both, the first is the general rules, the second is class specific. And you need to understand Stock BEFORE you read about SP, STX, or SM.

Scott
2009 Cobalt SS, DSP

These allowances 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.

So, GMS1 in STX sounds like a big grey area to me.

The section highlighted says it all. The changes from a GMS1 are all "indirectly" related to boost -- they directly change peak RPM (which can potentially add turbo RPM -- ergo boost) and the fuel flow vs air flow ratios (which can potentially add turbo RPM -- ergo boost). There's nothing in the documentation or published data from GM that speaks to directly modifying the turbo! Far from it. And I've seen no valid tests that demonstrate significant boost increases-- at the 6250 RPM speeds -- there are no 'before-and-after' boost level tests. All we have are anecdotal thoughts that the boost has risen -- drawn from looking quickly at the not-completely-accurate boost guage.

Bottom line: don't worry about it! No one in STX will care -- particularly if you haven't already won the National Championship in STX (if you've done that, expect to be protested for everything you've ever done to your car -- boost levels will be the least of your probems).

Scott

haha well put Scott.

Alright, I'm running in STX then... I don't plan on running slicks so STX is the only thing I could be competitive in.

I'm mouning the slicks and going out to play in DSP tomorrow. First time with the GMS1 -- It'll be interesting to see how much 'stick' I get under power...

This is my only opportunity to 'test and tune' before the March event in Mineral Wells, Texas. I'm hoping the GMS1 will be an advantage -- remains to be seen. I'm also hoping it doesn't snow or rain tomorrow -- this is Colorado after all.

Candidly, I'm not sure the GMS1 will be the hot ticket in STX. On my mostly-stock-powered 09 SS (GMS1, Hahn cold air, improved exhaust, Stiffy torque surpressor), it's almost too easy to spin the tires under power. Spinning tires aren't transmitting power to the ground. I can see throttle control being the new big deal for GMS1 cars. I don't know, I guess we'll see...

Scott

So, how did the autocross go with the GMS1 Scott?

Maybe it's because I'm running around with an open dif, but I just assumed that throttle control was a big deal for all of the Cobalts...

With the slight turbo lag (it's ever-so-slight) it's just enough to not to have to worry about the throttle precision. The LSD also helps with that. Slight throttle during tight corners the LSD really helps.

Hey John, You been AutoXing lately? According to this discussion and my new intercooler I think I am DSP now, but I'm not sure, as I haven't been keeping up lately. I'm going to the MirrorKhana event this Saturday though, so that should be fun. Hope to see you there!

Still wondering about if any autocross guys think they have benefited from a tune? To STX or not to STX? That is the question.

GMS1 isn't STX legal. It's quite clear. Not even close guys.

"Reprogrammed ECU (via hardware and/or software) may be used
in the standard housing. Traction control parameters may not be
altered. Altered engine controllers may not alter boost levels in
forced induction engines. Alternate software maps which violate
these restrictions may not be present during competition, regardless
of activation."

I see it as a gray area. We can boost 21psi stock. So, a tune boosting no more than that would be.......well I'm not sure. But, I'm kinda leaning towards a no. I would feel like I was cheating. So conflicted!

It's not a grey area. If you take a stock SS/TC and run it next to a GMS1 SS/TC at the same time, the GMS1 car will request more boost to make more power.

That's hearsay. GM hasn't told us that the GMS1 calls for more boost.

Boost changes indirectly resulting from allowed modifications are permissible

The ecu has been reprogrammed for more air and fuel. More boost is an indirect result.

That's what I was thinking.

I wanna post this on SCCAforums but afraid no one would understand how our ECUs work

So..., I've been debating (with myself - short conversation) how to answer this.

So it's a cold day (about 38), really dirty asphalt, dirty cold slicks, trying 450 lb springs front and back (per one suggestion) and a swaybar added.

The way I usually do things is to go like hell the first run -- really, really push the corners, if you spin out, no big deal, lay on the gas hard, so at least you have a good idea what the course will handle and you have at least two more runs to get it right. It you go to a Nationals, you'll see this method a lot.

On the 3rd corner (left) I lost it big time. 1. I entered the corner faster than I'd ever been able to in the past (more acceleration), 2. under power in 2rd I started spinning the fronts (remember, I'm on 285/30 x 18 Hoosiers), and everything got loose at once -- front and back. I left the course 90 degrees from the direction of travel, put both feet in (clutch and brakes), and barely slowed down.

So I punted a curb at the edge of the course, blew the right front Hoosier, didn't do anything to the alignment (it's been checked already), didn't hurt the rim - it's straight, but I think I pushed the right LCA back because there's a caster variance that says the right front is now more straight up and down (I hit it almost straight-on). Nothing's bent, or cracked, or otherwise pranged in any way. I've been over it with a fine toothed comb. (I'm going the 'adjust' the right front LCA this weekend.) It drives just fine; I'm impressed with how tough it is!

I went into the pits, got under the car and checked everything, put my STX 245s on the car, and ran three more runs without incident. But I definitely tip-toed that first street-tire-run. Otherwise, I love it! WOW, does it accelerate! It's almost shocking with the Hoosiers - even spinning, they stick so much harder than street tires - it really plants you in the seat...

Before GMS1 - stock except for a Cold Air and Cat Back, on a straight section, on the floor in second (in the power band), there was no tire spin (also mostly true in the corners). Now, still on 285s, I can spin the slicks in second under power pretty readily on the straights or in the corners. That's why I was mentioning having to go back to throttle control in an earlier post; I had been used to sticking the pedal on the floor most of the time. It might still be OK with hot, sticky tires, on a summer road - I'll have to see.

Scott

Some questions are best left unasked...

Scott

probably right.............to late ;) just interested in other perspectives.

http://sccaforums.com/forums/410823/...ad.aspx#410823

Thanks Scott. You input is always appreciated. Maybe with the added power you would benefit from some more rear spring?