Creating Guides for AutoX classes, need your help

[ACM]

That's OK - it wasn't me who mentioned Mod actually, it was...TechBenchTony, I think ?

I'm purely focused on (E)SP rules, and I know quite a bit about those, but I know _very_ little about the other classes - too much data, my head get full.

Charles

 

[kwheeler]

Yeah, I get pretty focused on the Modified class because thats where I run but I've been looking at SM and SP lately. Once I get the Talon running it'll be my daily and backup auto-x car so I've been trying to figure out what I want to modify. Unfortunately for me when I bought it the turbo and exhuast manifold were totally shot. I bought an Evo III 16G and exhaust manifold but that puts me in SM. I'd rather run SP so I'm looking to possibly buy a good condition used 14b, it all depends on how much I have to spend and whether I can find one in good shape.

kwheeler

 

[TechBenchTony]

Yeah, I get pretty focused on the Modified class because thats where I run but I've been looking at SM and SP lately. Once I get the Talon running it'll be my daily and backup auto-x car so I've been trying to figure out what I want to modify. Unfortunately for me when I bought it the turbo and exhuast manifold were totally shot. I bought an Evo III 16G and exhaust manifold but that puts me in SM. I'd rather run SP so I'm looking to possibly buy a good condition used 14b, it all depends on how much I have to spend and whether I can find one in good shape.

kwheeler

Your right on the SM for the engine thing. I forgot about that exception till i reread the rules yesterday. Sorry for causing confusion there. But I still don't understand how you could swap the engine into one or the other, and still run in SP. at the very least i would think that would be considered a turbo change. Which section of the rules in Street Prep are you looking at? I am not afraid to admit that I am wrong, but I am just not seeing it and neither does a friend of mine who is part of the classing for Auto Sports Northwest

 

[ACM]

The engine swap comes in under a couple of places. Firstly 15.1.C (page 84) - update/backdate for cars on the same line in Appendix A (page 190/191 for DSMs). Note the wording of C "The updated/backdated part or the part to which it is to be attached may not be altered, modified, machined or otherwise changed to facilitate the updating/backdating allowance." and also "The updating and/or backdating of engines, transmissions or transaxles must be done as a unit;
component parts of these units may not be interchanged." So engine mounts can't be changed unless there's another rule explicitly allowing this, and also, the definition of engine unit vs component...

Now move to 15.10, startng on page 93. 15.10.C.3 is what effectively bans FMICs for DSMs (unless you run the IC pipes out of the SMIC port . 15.10.C.4.b states "Turbochargers or superchargers may be updated/backdated only in conjunction with the accompanying complete engine unit." Finally, 15.10.J adresses the incompatible engine mounts between 1Gs and 2Gs - note that "attaching to the factory locations" refers to the last non-removable component, so that's the bodyshell on one side and the engine block on the other.

I discussed this in great detail with the SPAC when it first came out to make sure we all had the same understanding. Of course that all amounted to nothing when the Nationals moved from Forbes super-sticky concrete to the HPT sand pit - boost response being far more important on tight low-grip courses than top-end power, so the 2G compression and toy turbo became advantageous. I guess two motors are needed - 1G/14b for open, grippy venues, and 2G/T25 for HPT Nationals At this point I can change an engine in a few hours, so perhaps this is a practical option

 

[TechBenchTony]

The engine swap comes in under a couple of places. Firstly 15.1.C (page 84) - update/backdate for cars on the same line in Appendix A (page 190/191 for DSMs). Note the wording of C "The updated/backdated part or the part to which it is to be attached may not be altered, modified, machined or otherwise changed to facilitate the updating/backdating allowance." and also "The updating and/or backdating of engines, transmissions or transaxles must be done as a unit;
component parts of these units may not be interchanged." So engine mounts can't be changed unless there's another rule explicitly allowing this, and also, the definition of engine unit vs component...

Now move to 15.10, startng on page 93. 15.10.C.3 is what effectively bans FMICs for DSMs (unless you run the IC pipes out of the SMIC port . 15.10.C.4.b states "Turbochargers or superchargers may be updated/backdated only in conjunction with the accompanying complete engine unit." Finally, 15.10.J adresses the incompatible engine mounts between 1Gs and 2Gs - note that "attaching to the factory locations" refers to the last non-removable component, so that's the bodyshell on one side and the engine block on the other.

I discussed this in great detail with the SPAC when it first came out to make sure we all had the same understanding. Of course that all amounted to nothing when the Nationals moved from Forbes super-sticky concrete to the HPT sand pit - boost response being far more important on tight low-grip courses than top-end power, so the 2G compression and toy turbo became advantageous. I guess two motors are needed - 1G/14b for open, grippy venues, and 2G/T25 for HPT Nationals At this point I can change an engine in a few hours, so perhaps this is a practical option

Wow... Ok. Well, Like i said, I will admit when I am wrong. That makes sense. I can see where the advante would be, but for me, having a second motor make for way too much work for me, but if it helps you win. More power to you or less power, depending on the motor you go with for what race

 

[ACM]

There are a couple of important rule changes for (E)SP in the 2009 season

Big brake kits are now allowed. There are restrictions however :
1. Rotors must be ferrous metal except for standard parts. Aluminum rotor hats are allowed. Rotor dimensions (diameter and thickness) must be equal to or greater than standard parts. Cars originally equipped with solid (non-vented) rotors may utilize vented rotors.

2. Cross-drilled and/or slotted brake rotors may be used. Slots/holes are permitted only in
the braking area of the rotor. Rotors featuring a drum-type parking brake in the hat area of the rotor may not be drilled/slotted in the parking brake area.

3. Brake calipers may be replaced, provided the number of pistons is equal to or greater than the original number of pistons. Caliper mounting brackets may be replaced to accommodate this change, but may serve no other purpose. Alternate caliper brackets must bolt to the original caliper bracket mounting location(s).

It is not clear to me at this point whether the OEM handbrake must be retained, or whether it can be changed to a different type. Also note that due to the rotor thickness restriction, you cannot use the off-the-shelf Wilwood kit, because the rotor is thinner than OEM. All is not lost however, because Todd at TCE now has an OTS kit that fits the bill perfectly
A functional E-brake must be present - period, so any changes to E-brake form are permissible, so long as it functions.


Camber kits are now allowed - with restrictions :
1) On double/unequal arm (e.g. wishbone, multi-link) suspensions, only the upper arms OR lower arms may be modified or replaced, but not both. Non-integral longitudinal arms that primarily control fore/aft wheel movement (e.g. trailing arm(s) or link(s) of a multi-link suspension) may not be replaced, changed, or modified.

2) On arm-and-strut (MacPherson/Chapman) suspensions, the lower arms may be modified/replaced OR other methods of camber adjustment as allowed by paragraphs 15.8.C, D, or G may be used, but not both.

3) On swing or trailing arm suspensions, the main arms may not be modified or replaced, but lateral locating links/arms may be modified or replaced.

4) The replacement arms or mounts must attach to the original standard mounting points. All bushings must meet the requirements of 15.8.C. Intermediate mounting points (e.g. shock/spring mounts) may not be moved or relocated on the arm, except as incidental to the camber adjustment. The knuckle/bearing housing/spindle assembly cannot be
modified or replaced.

Loosely translated, 2Gs can now change either the upper arm or both lower arms in a 2G front suspension, and the upper arm or the lower LATERAL arm in the rear suspension. The 2G rear suspension is considered multi-link, not double A arm.

Since the SCCA refused my (perfectly reasonable) request to restrict these allowances to my 2G only, these changes only mean everyone else got a whole lot faster too, simply raising the cost of entry another few thousand dollars.

Unrestricted seats are back as well - you can dust off your 8lb CFK shells and bolt them back in - assuming you didn't sell them after they were banned ! Kart seats are still banned, regardless of position.

There are detail changes to the engine mount rule - it is unclear whether they disallow fitting a 1G into a 2G. When I find out I'll pass it on.
The new wording loosens the restrictions regarding the ratio of metallic to non-metallic composition, so 1G-in-a-2G is unaffected.

 

[eltoshan]

What's the ruling on offset bushings in SP? I'm under the impression that they are legal? How much static negative camber can be had without sacrificing braking performance? I autocrossed a FS 335i all last season, so coming from a super camber-challenged, heavy but well balanced RWD car, I really have no idea what to expect next season in a 2G AWD.

 

[Scott McIntyre]

How much static negative camber can be had without sacrificing braking performance?

In my experience with a 2G AWD, -3º static front camber adversely affected braking in autox, so I switched back to -2.5º. YMMV.

 

[everbruin]

i think offset bushings are legal if metal content remains the same

 

[9!'clipseDOHC]

This thread has long been dead but I started working on this anyway. I think that it will be very beneficial to DSMers looking to get into autox and hopefully can also serve as a quick reference guide for current autoxers as well since most of us are only familiar with our own classes.

Please go through and let me know if anything is incorrect or should be changed or added. I don't care if it sounds nit-picky or minor, I want to make this article really good and useful. I am pretty new to the sport myself and am also no longer autoxing my DSM and am instead racing my Evo in STU, so that is what I am most familiar with.

I have a few clarifications to ask about right off the bat. What class would aftermarket cams move you into? Level 1 Prepared? Also what about stroker motors? if you know of any other common DSM mods that aren't covered let me know also and I will add them.

Without further adu (sp?), here is what I've got so far:


DSMtuners.com SCCA SOLO Autocross Guide

You must be logged in to view this image or video.

Below is a quick reference guide for selecting an SCCA SOLO Autocross class. For full rules, download the 2012 SCCA Rulebook. The following guide applies to the 1990-1999 Mitsubishi Eclipse, Eagle Talon, and Plymouth Laser models. Any modification in a lower class can also be used in a higher class. Any modification not specifically allowed is prohibited.

But first, what is Autocross? Autocross is a type of amateur racing event focusing both on driver skill and vehicle handling and performance. Most Autocross events take place in parking lots or abandoned airfields with cones laying out the course. Because of this they are found all over the country and are more affordable then road course racing events. They generally feature speeds no faster the what you would encounter on a public highway. Autocross events build driver skill, provide an safe outlet for performance driving, and invoke some serious competition!

SCCA Autocross, also called SOLO, is based on a PAX index, which is basically a handicap designed to equalize all cars and focus on the driver's skill. Cars are placed into classes based on the type of car and modifications done. Each class is assigned a PAX modifier which is multiplied to your raw lap time to equal your PAX time, which is what is scored. For instance, an all stock GSX in DS has a PAX of .821 while an all stock GS has a PAX of .799. If the GSX ran the course in 60 seconds, his PAX time would be 49.26 (60x.821=49.26). So, for the GS to beat him, he would only need to run faster then a 61.65 (49.26/.799=61.65).

Ready to get started? To find races near you, click the Find Your Region link on the SCCA website.

Stock Class:

The stock class provides a nice way to be compete without spending a whole bunch of money on performance parts. However, since most DSM's are now 13-23 years old, they have at least a few modifications done that will bump them up in class. Even something as simple as a hacked air can, a downpipe, or a performance clutch will prevent you from being eligible to compete in the stock class. In the stock class you can run DOT legal R-comp tires such as the Hoosier A6, Goodyear Eagle RS, Hankook Z214, and Kumho V710.

You must be logged in to view this image or video.

• DS: Turbo/AWD PAX: 0.821
• GS: Turbo/FWD PAX: 0.814
• HS: Non-turbo/FWD PAX: 0.799

Engine Mods Allowed:
OEM style drop in air filter in stock "unhacked" air can.
Cat-back exhaust
Any spark plugs or wires
0.020" overbore w/OEM cast pistons of same weight and CR
Oil catch cans (provided the PCV still functions)
Silicone hoses

Suspension and Brake Mods Allowed:
DOT legal tires regardless of treadware rating
Shock Absorbers (OEM Style, no more than 2-way adjustable)
Substitution, addition, or removal of a single anti-roll bar and supporting hardware
Aftermarket wheels (OEM width & diameter, offset within +/- .25inch including spacers)
Extended wheel studs and aftermarket lug nuts
SS Brake and clutch lines are allowed for cars 89-92 model years only
OEM fitment Brake pads of any material
"Speedbleeders" are allowed
Alignments must be made with OEM allowable adjustments

Other Mods Allowed:
Aftermarket gauges
Turbo timers
Grounding kits
Dataloggers
Hood pins
Alternate steering wheels (within 1" of OEM diameter and must retain airbag if originally equipped) and shift knobs
Spare tire, tools, and jack my be removed
Roll bars and cages
Scattershields


Street Touring Class:

The street touring class is designed around using normal, every day street tires. It is for this reason that it has a nice low PAX and also allows for a large number of basic modifications to help turn your daily driver or street car into a well-rounded autox car. It is also generally a very affordable class to race in with basic mods most people do anyway and without the high cost of dedicated track wheels and tires. The tires of choice for street touring are the Dunlop Direzza Sport Z1 Star Spec and the Hankook R-S3, although any extreme/max performance summer tire will still work well.

You must be logged in to view this image or video.

• STX: Turbo/FWD/AWD PAX: 0.822
• STC: Non-Turbo/FWD PAX: 0.820

Engine Mods Allowed:
Lightweight battery (must be 12 volts)
Battery may be relocated to the trunk
Baffled oil pans
Intake system up to the turbo inlet for turbo car or throttle body for N/A cars. (MAF must remain in stock location)
Exhaust manifolds, headers, downpipes, high flow cat.
ECU tuning using V3, piggybacks, chips, or flashes (except boost control must remain stock)
Lightweight pulleys
Polyurethane motor mounts
LSD: STX AWD - No aftermarket LSD's can be added, STX FWD - Any LSD can be added, STC - No LSD's can be added

Suspension and Brake Mods Allowed:
Any struts including coilovers
Lowering springs
Polyurethane suspension bushings
Adjustable camber plates
Camber bolts
2-point upper strut bars may be added front and rear
Substitution, addition, or removal of any anti-roll bars
Tires must have a minimum treadware rating of 140
Maximum tire width: STX AWD - 245, STX FWD - 265, STC - 225
Maximum rim width: STX ADW - 8", STX FWD - 9", STC - 7.5"
Any metal brake rotors (must be equal to or larger then stock, can be drilled or slotted)
Any calipers (must have same or greater number of pistons)
SS brake lines
Brake air ducts
ABS may be disabled but not removed

Other Mods Allowed:
Front seats may be replaced (New seats must weight at least 25 lbs and be fully upholstered)
Mud flaps, rear wings, front lips, fog lights may be removed
OEM wings my be added from other DSM's
Any steering wheel (must retain air bag if originally equipped)
Fender lips may be rolled but not cut or flared


Street Prepared Class:

The street prepared class is where you start to see some more power and are again allowed to race on DOT legal R-compound tires. You can up the boost and add in the supporting mods like fuel, clutch, and intercooler. However, the added power can often be more of a hindrance then a help to new drivers. If that is the case, focus on the skills and seat time instead of more performance parts.

You must be logged in to view this image or video.

• ESP: Turbo/FWD/AWD PAX: 0.848
• FSP: Non-Turbo/FWD PAX: 0.838

Engine Mods Allowed:
Any size fuel injectors, lines, pumps
Aftermarket intake manifold
FMIC of any size
Aftermarket reticulated bypass valves may be used (this also allows the use of a 1g bypass valve on a 2g)
Manual boost controllers
ECU tuning (including boost tables)
Water injection systems
Any exhaust (as long as it is quiet and terminates behind the driver)
Upgraded radiators (must mount in same location and must be the same size or larger)
Cooling fans and shrouds can be changed
Any clutch and flywheel
LSD's are allowed to be added
0.0472" overbore w/OEM cast pistons of same weight and CR
Intake and exhaust ports and opening my be port matched up to 1"
Adjustable Cam pulleys

Suspension and Brake Mods Allowed:
Wheels of any diameter, width, or offset may be used
Wheel spacers
ABS may be disabled but not removed
Any brake line, master cylinder, vacuum brake booster, or brake pro- portioning valve may be used.

Other Mods Allowed:
Remove A/C system
Any steering wheel can be used (even if it removes the airbag)
Any fully upholstered front seats can be used regardless of weight
Front lips can be added
Rear spoilers may be added (can not extend more then 10" from the bodywork in any direction)
Fuel cell can be installed (must be within 20% of factory capacity and mounted within 6" of original)
Radio and speaker can be removed (but not the wiring)
Sunroof cars can be converted to solid roofs
Rear view mirror and sun visors can be removed


Street Modified Class:

To be fully built in the street modified class takes a lot of time and money. It also pushes the border between street car and race car. Yet in spite of this, most DSMers wind up in this class due to previous mods. A carbon fiber hood, turbo upgrade, or atmospherically vented BOV by themselves will land you in this class. If you find yourself here, don't despair, it just means you have the ability to do more mods without jumping classes! The big thing here is upgraded turbos. Chose wisely and try to balance between quick spool and high power!

You must be logged in to view this image or video.

• SM: AWD PAX: 0.866
• SMF: FWD PAX: 0.852

Engine Mods Allowed:
Engine swaps with other DSM's
Any fuel system (5 gallon minimum fuel cell. Fuel cell must be at least 6" away from the ground)
Metal motor and drivetrain mounts
Any turbo
Any ignition system
Blow off valves vented to the atmosphere

Suspension and Brake Mods Allowed:
Any drivetrain
Any brakes (except for carbon or ceramic rotors)

Other Mods Allowed:
Carbon fiber or fiberglass hood and front fenders
Rear passenger seats and seat belts my be removed
Spliters, spoilers, and canards can be added
Aftermarket side mirrors my be installed (must have 15 sq. in. of reflective material)
Pop-up headlights can be converted to static headlights (must retain high and low beams)

 

[snowborder714]

Nate has posted the above in a sticky.
http://www.dsmtuners.com/forums/roa...-dsmtuners-com-scca-solo-autocross-guide.html

Please let us know if there's anything on there that you'd want further explained/clarified, or that you think is incorrect or needs added.

 

[gixrman]

In the sticky it states tire width is limited to 245 in the ST class and its not mentioned in SP and SM so i'm guessing its carried over. And as metioned I have all the mods that are going to force me into the SM class anyway just want to know if I can go wider but if its pointless.

 

[ACM]

In the sticky it states tire width is limited to 245 in the ST class and its not mentioned in SP and SM so i'm guessing its carried over. And as metioned I have all the mods that are going to force me into the SM class anyway just want to know if I can go wider but if its pointless.

No it's not carried over. SP allows any size/width/diameter wheel and DOT-legal tyre, no size restrictions at all.

SM has an optional, voluntary 275 width restriction, in that should you choose to run 275 or narrower tyres, your calculated minimum weight limit drops by...200 lbs I think ? But it's not mandatory, SM allows any size DOT-legal tyre.

 

[2gmitsueclipse]

Would I need to change to a recirculated o2 housing from an external o2 housing to stay in an SP class?

I am trying to figure out where exactly I would place as I am new to SCCA events.

Car is 1998 Eclipse GSX
Mods are:

Open element air intake
full ss clutch line
3in o2-back exhuast. (no cat)
external dump o2 housing
short throw shifter w/ solid shifter and cable bushings
Evo 9 BOV
Evo 8 wheels (stock evo tires as well)

 

[jtmcinder]

Yes, because all exhaust gases must exit the side or rear of the car, somewhere behind the driver. That's a general SCCA rule and applies to all classes.

 

[ileagleracing]

Turbo back exhaust is open in ESP, but JTMCinder is right, the exhaust has to exit past the driver. And if you have any blow by from the motor, it should exit past any flammable items (this is why Charles car caught on fire at Nationals).

Swap your O2 housing, run a stock BOV, add a cat and run STX. Your car would be more competitive that way.

Samuel Krauss
Omnis Axis Proturbo
08 Expedition (TSP)
04 S4 (STU)
98 Talon (SMish)
95 Talon (STX)

 

[2gmitsueclipse]

Can the o2 housing still be tubular or should it go back to stock?

 

[9!'clipseDOHC]

In Street Touring you can run a tubular o2 housing, it just need to be recirculated. Keep in mind it will need to be an internal wastegate though, unless you want to go to Street Modified.

 

[2gmitsueclipse]

Thanks for the advice. I will search for a tubular o2 housing and 3in cat to stay in STX. This car is still on the t-25, so I am internally gated.

 

[ACM]

I keep meaning to point out the following, but I always forget - from the Street Prepared section :
FMIC of any size
Aftermarket reticulated bypass valves may be used (this also allows the use of a 1g bypass valve on a 2g)

Any BOV, recirculating or otherwise, is allowed - or none at all if you're feeling brave.

FMICs are technically legal, but there is no way to mount one per the rules. SP specifically prohibits modifying splash guards and the like for any reason - the sole exception being the outer extremities of fender splash guards. Since the plastic panels in the region of the radiator have to be modified to fit an FMIC (at least on a 2G), that renders an FMIC illegal. One could conceivably route the piping via the SMIC/trans cooler ducts in the front bumper, and that would be legal - legal perhaps, practical not so much.

 

[9!'clipseDOHC]

I keep meaning to point out the following, but I always forget - from the Street Prepared section :
FMIC of any size
Aftermarket reticulated bypass valves may be used (this also allows the use of a 1g bypass valve on a 2g)

Any BOV, recirculating or otherwise, is allowed - or none at all if you're feeling brave.

FMICs are technically legal, but there is no way to mount one per the rules. SP specifically prohibits modifying splash guards and the like for any reason - the sole exception being the outer extremities of fender splash guards. Since the plastic panels in the region of the radiator have to be modified to fit an FMIC (at least on a 2G), that renders an FMIC illegal. One could conceivably route the piping via the SMIC/trans cooler ducts in the front bumper, and that would be legal - legal perhaps, practical not so much.

Thank you for pointing those things out! I am pretty new to the sport myself and I am sure that you know more about autoxing then I ever will.

I don't know if the rules have changed in the past few years but according to the 2012 SOLO rule book, Street Prepared, Section 15.10:
d) No changes are permitted to blow-off/pop-off valves.
e) Compressor bypass valves (CBVs) are considered part of the air intake system and may be added, replaced, or updated/ backdated independently of the other components of a forced induction system.

12.14 BlOW-OFF VAlVE (BOV) / POP-OFF VAlVE (POV)
A device intended to limit maximum boost pressure in the engine inlet system by opening to vent the inlet system to the outside atmosphere when a preset boost value is reached.
12.15 COMPRESSOR BYPASS VAlVE (CBV)
A device intended to allow a supercharger or turbocharger's compres- sor output to recirculate back to the supercharger or turbocharger inlet when the throttle plate is closed. The purpose of this recirculation is to reduce boost lag when the throttle plate is reopened. A CBV is refer- enced to intake manifold vacuum and opens when manifold vacuum exceeds a preset value. It is closed under boost. CBVs installed by OEMs operate as described above. Some aftermarket CBVs vent to the atmosphere, and are marketed as Blow Off Valves or Pop Off Valves, although their operation is otherwise identical to the OEM CBVs.

By definition a compressor bypass valve recirculates air back into the intake system while a blow-off valve vents it to the atmosphere. The terms are often incorrectly used interchangeably and, especially with DSM's, referred to as BOV's regardless of the design. Let me know if perhaps I am reading it incorrectly.

You are definitely correct on the FMIC though, I just confirmed that in the rule book:

15.10.C.3. As utilized only on engines originally equipped with forced induc- tion, induction charge heat exchangers (known as "intercoolers" or "charge air coolers (CACs)") are unrestricted in size and configu- ration. Air-to-air CACs and radiators for air-to-liquid CACs must be cooled only by the atmosphere, except for standard parts. Body panels, fascias, or structural members may not be cut or altered to facilitate CAC installation.

 

[ACM]

You are correct about BOV/pop-off valves, however we always confuse the definitions in the DSM world. The DSM world uses the two terms interchangeably, where they are actually two completely different animals.

Blow-off/Pop-off valves directly control boost, it is their sole purpose - these are the valves used on Indy car engines, they are extinct in the road car world. These valve cannot be monkeyed with in any way shape or form. But since no road-going vehicle built in the last 30 years was ever equipped with one, it's largely irrelevant.

Compressor Bypass Valves have no role in controlling boost levels, and their function is controlled by intake vacuum levels - not positive pressure. CBVs can be deleted, added, changed or modified etc. The last sentence from 12.15 is key :
Some aftermarket CBVs vent to the atmosphere, and are marketed as Blow Off Valves or Pop Off Valves, although their operation is otherwise identical to the OEM CBVs.

So regardless of where the vented air is routed, it is still a CBV so long as it does not serve to regulate boost. Where the air goes is not central to the definition, it's the function as detailed in that section.

 

[9!'clipseDOHC]

You are correct about BOV/pop-off valves, however we always confuse the definitions in the DSM world. The DSM world uses the two terms interchangeably, where they are actually two completely different animals.

Blow-off/Pop-off valves directly control boost, it is their sole purpose - these are the valves used on Indy car engines, they are extinct in the road car world. These valve cannot be monkeyed with in any way shape or form. But since no road-going vehicle built in the last 30 years was ever equipped with one, it's largely irrelevant.

Compressor Bypass Valves have no role in controlling boost levels, and their function is controlled by intake vacuum levels - not positive pressure. CBVs can be deleted, added, changed or modified etc. The last sentence from 12.15 is key :
Some aftermarket CBVs vent to the atmosphere, and are marketed as Blow Off Valves or Pop Off Valves, although their operation is otherwise identical to the OEM CBVs.

So regardless of where the vented air is routed, it is still a CBV so long as it does not serve to regulate boost. Where the air goes is not central to the definition, it's the function as detailed in that section.

I see what you are saying but it can be read the other way too. If true blow-off/pop-off valves aren't used anymore, why add that sentence and introduce possible confusion. "Some CBV's vent to the atmosphere and are called BOV's. No changes are allowed for BOV's."

 

[2gmitsueclipse]

In my case would the Evo 9 bypass valve keep me in the STX class as it technically is an OEM piece, just not on the 2g DSM. On the allowed mods listed, I took it as I could have and intake, just nothing after market after the turbo, which would not allow for the EVO 9 bypass valve or SMIC hardpipes.

 

[zachakagoat]

No need for the change in BOV you can mod the stock 2g to hold 25psi reliably. See my build log for details and pictures.