This is intended to be a listing of ALL specific mods legal for STX. The priority is subjective, but should reflect that the stuff that gives you more benefit has a higher priority (ignoring cost/benefit). This isn't intended to be a discussion of the best xxxx as there are a million threads discussing individual components (e.g. this coilover vs that).

DISCLAIMER: THROWING MONEY AT YOUR CAR WON'T MAKE YOU FASTER UNTIL YOU CAN PUT THE POWER TO THE GROUND SMOOTHLY. This list is only to illustrate what COULD be done to your STX WRX. National level winners have won with far less than everything on this list - BUT GREAT DRIVING SKILL. DRIVING SKILLS WILL ALWAYS HAVE THE GREATEST BENEFIT!

This subjective list is meant to be illustrative of how you would incorporate mods in stages based on benefit. It makes sense in some cases to do multiple things at once when doing major work (since the labor would be repetitive) even though they aren't both in the same category.

What am I missing? Any thoughts on the general priority listing? This should be as specific as possible regarding mods allowed. Feedback has and will continue to be incorporated.

High Priority
• Wheels 17x8, light as possible
• Tires 245/40/17, 245/35/17, or 235/40/17, (treadwear rating >140)
• Fenders rolled to accommodate tires (more important for us wagon owners)
• Performance alignment
• Coilovers/Shocks/Springs
• STi Group N tophats rear
• Camber plates front
• Camber adjustment for rear – camber bolts OR adjustable lateral links with pillow ball upper mounts OR camber plates
• Front swaybar
• Rear swaybar
• Endlinks front & rear
• Swaybar mounts and bushings
• Rear strut brace (wagon)
• Engine management (stock boost controls)
• Uppipe
• Downpipe
• Turboback lightweight, high flow exhaust which must have at least one cat no further back than 6” of end of last oem cat in the system (stay tuned for emissions legality rulings by SCCA) and meet sound requirements
• Trans and differential fluid (aka Redline shockproof, Uncle Scotty’s mix, etc)

Priority
• More aggressive brake pads
• High quality brake fluid, e.g. ATE Superblue or equivalent
• Stainless steel brake lines
• Lightweight racing seats (25 lbs min. weight, stock bolt locations)
• Lightweight battery
• Weight removal - Delete A/C
• Front control arm (rear transverse link) bushings including offset bushings (gains caster)
• Short throw shifter kit with bushings
• Lightweight crankshaft pulley
• Underdrive accessory pulleys
• Header or PnP OE exhaust manifold
• Intake (pre-turbo stuff only)
• Turbo Inlet Hose
• Harness
• Big brake kit
• Motor mounts
• Transmission mounts

Low Priority
• Rotor upgrade – lighter, slotted
• Caliper upgrade – using same mounting points
• Steering rack bushings
• Front trailing link bushings
• Rear trailing arm bushings
• Lateral link bushings (if not already using adjustable lateral links)
• Differential mount bushings
• Rear differential fluid upgraded
• Rear strut brace (sedan)

Unneccessary – but legal
• Front strut brace
• Grounding kit
• Rollbar or cage
• Water wetter in coolant
• STi pitch stop
• Battery relocation to trunk
• Copper spark plugs (indexed to 12 o'clock)
• Thermostat
• Parts bin matching
• Factory overbore allowance of .020

All bushings listed are assumed to be an upgrade when going stiffer than stock. Also must comply with STX rules stating that the ratio of metal/non-metal must not be increased.

S
• Steering rack bushings (illegal in STX)


Completely legal in all classes EXCEPT Stock classes.

steering rack bushings are legal,

as well as you must have a cat within 6 in. of your last cat

also camber bolts in the rear are a good idea

Updated steering rack bushings to legal
Added camber bolts for rear
Clarified exhaust with one high flow cat within 6" or last oem cat

If you are building the car to be 100% all out STX...i'd move the underdrive/lightweight pully set into the higher priority category.


Every little bit counts at the highest levels.

Harness or CG lock- high priority :)

Is removing weight legal in ST? I know you can't run without the back seat, would this apply to sound deadening, radio, etc...?

Don't forget a rollbar or cage...completely legal since it is a "safety" modification.

Instead of camber bolts for the rear, it's probably better to get adjustable lateral links...

back seat has to stay.

complete removal of AC system and radio (except wiring) is legal as long as any holes are covered.

a cheap harness that bolts into seatbelt locations (and stock seat belt remains) is 100% better than CG lock any day.

Theres no rule like the steering wheel that prevents an Impreza owner of replacing their driver and passenger seat, is there. I dont remember anything like that. Because of the airbag, that is.......

You could add that to the list. Replace front seats as long as they meet the new 25lb rule--seat and rails--using stock mounting holes.

seat-time!!!!

I think lightening the car (including replacing/moving the battery) is probably a higher priority...probably more of a priority than everything in your 'priority' section except brake pads.

You can also add intake, MAF elbow thingy (if the new intake doesn't already replace it), and a turbo inlet. You might also want to note that you can have adjustable lateral links OR camber bolts OR camber plates in the rear, but not more than one form of camber adjustment.

Another few notes:
While moving the battery to the rear helps weight balance, you are adding 5lbs of wire to do it.
Rolling the fenders isn't necessary unless you've lowered your car enough to screw up your roll centers and degrade performance. But its a free mod and doesn't hurt anything.
Water wetter in the coolant is questionable. I've never had my car overheat...ever. In fact, the temp seldom moves once its up to operating temp.
Headers...would recommed ported and polished stockers or equal length, as tuned length delays spool and reduces low RPM response.

seat-time!!!!

2nded.

http://www.autocross.com/evolution

--kC

Low Priority
• Short throw shifter kit with bushings


I agree that the Short throw shifter kit isn't a high priority mod by a long stretch, but the shifter bushings are one of the best mods I ever did to my 99RS. They make a notable improvement in shift feel and shift speed (as it gets rid of a lot of that "bound up drivetrain" sensation on quick 1-2 shifts). IMHO, the shifter bushings are at least medium priority parts for an autocross car (that also happen to be cheap and easy to install, too). :)

Push the motor mounts up the list, install them when you do the up-pipe, you'll have more than half the work to replace them done anyways at that time. They're worth the money and your time is already being spent on the labor.

Push header down the list, you'll gain peak HP but lose spool, depending on how your dyno sheet looks you may not want to do this one at all. Maybe consider P'n'P on the stock manifold instead.

Turbo inlet hose and intake should go on your power list. And as soon as you think you're done with all your power mods get a dyno tune by a GOOD tuner.

Rear pillow ball upper mounts and adjustable lateral links are a legal combination. IMO, that's the way to go, simple and easy changes to rear camber and toe are priceless.

Be careful combining underdrive accessory pulleys with the lightweight battery. Or if you do keep a jump-pack with you in grid.

For years I was a firm believer that a BBK in STX was a waste of money. Then we got one, because we were facing a significant cost to replace calipers anyways after one seized, and now I know better.

Also legal and not specifically listed:

STi pitch stop (minimal beneift but hey we were in there to replace the transmission anyways :) )
Front control arm bushings, including the Whiteline offset bushing.
Rear trailing arm bushings
Transmission and differential fluids, this is a CRITICAL one as the factory fluid is junk.
Spark plugs, copper plugs will wear out VERY quickly but can possibly help with a HP or 2.

And the way to get fast is always seat-time as was already mentioned. Throwing money at a car won't make you faster, in fact it often makes you worse by helping to hide where you are making mistakes.

Low priority and priority appear to be almost completely flipped.

The cat doesn't have to be WITHIN 6" of the last cat. It just cannot be any further back than 6" of the last cat. It can be as far forward as you like.

Also, if you can find grippy tires that fit your driving, 245/35-17 is an excellent size.

I would pull all the illegal items off your list (or make a separate "illegal" list). It's confusing to us simple-minded types the way you have it. :)

Were the radio & speakers optional on the WRX (in a line-item way)? If not, I don't see a provision to remove them in either stock or ST rules.

Definitely don't see any provision for removing sound deadening.

• Ground wiring


Grounding kits are only covered in the Stock portion of the rules but it states

“Grounding kits” specifically designed to support sound
systems are permitted but may serve no other purpose.

I interpret that as grounding kits are not legal (under the heading of "If they don't say you can do it then you can't). :D

2007 rules added grounding kits to the ST ruleset.

New 14.9.B

"The addition of electrical grounding cables and associated distribution blocks/terminals is permitted. Holes may be drilled for mounting only. This does not permit the use of electrical enhancement components such as condensers, voltage controllers, etc."

Rolling the fenders isn't necessary unless you've lowered your car enough to screw up your roll centers and degrade performance. But its a free mod and doesn't hurt anything.

Wagons need it with serious rolling stock.

• Tires 245/40/17 or 235/40/17, grippy as possible

I thought it had to be over 140 treadware.

>=140, yep.

I would pull all the illegal items off your list (or make a separate "illegal" list). It's confusing to us simple-minded types the way you have it. :)

Were the radio & speakers optional on the WRX (in a line-item way)? If not, I don't see a provision to remove them in either stock or ST rules.

Definitely don't see any provision for removing sound deadening.

i agree with jen. take off anything on that list that is illegal. the subject of this thread is "listing of all legal stx mods" putting the illegal stuff on there jsut makes it more confusing and the illegal list can go on for pages. its easier to list everything you CAN do. anything not on the list is therefor illegal.

radio and speakers is not legal to remove. also sound deadening is not legal like jen said.

oh... and btw... if you want to win... consider everything a priority ;)

Thanks for the feedback, this list is really coming along.
First edit - I agree with jcroy66 & angryfist - Illegal items removed from the top list.
I put these on here since I wasn't 100% sure in the first place and knew that whatever was wrong could be corrected.

For future reference, these were some things that were unclear (to me) but ARE illegal (removed above):
PnP Intercooler Elbows - No intake mods between turbo and engine

Intercooler Hose - No intake mods between turbo and engine

PnP Turbo - No intake mods between turbo and engine

PnP Throttle Body - No intake mods between turbo and engine

Weight removal - can't remove sound deadening, wagon roof rails, radio, or speakers. Wagon owners cannot change folding backseat to fixed (lighter) STi backseat.

Many edits made:

WJM - moved lightweight and underdrive pulleys up in priority

BigSky & WJM - added harness

Wagonman - added rollbar/cage

Impreza01 - added adjustable lateral links

WRX 2.0 - clarified racing seats

Waktasz - moved "lightweight" items up

Scooby 921 - added intake stuff, rear camber notes, header notes and did some re-prioritizing

Warp3 & PhilC & afpdl - did some major re-prioritizing, few adds

jcroy66 & tetrapunk- corrected the cat verbiage, clarified tires

Thanks all - hopefully this continues to get more comprehensive and (subjectively) accurate as we go.

I still have the generic "suspension bushings" listed - have we got all the specific legal bushings covered yet?

Think of the intake mods as everything before the turbo. Everything from the turbo to the engine is illegal.

Low priority and priority appear to be almost completely flipped.

As noted above- a bunch of stuff was flipped around. If you disagree with the order tell me what specifically and why.

Well you initially had just about all weight reduction in low priority. Reducing weight or adding power should always make you faster. And in the priority area you had a bunch of things that increase feel but dont really have an affect on your times i.e. brake fluid/lines, motor mounts, tranny mounts etc... They are not bad modifications but they dont really provide a benefit over the stock parts when you put it against a clock.

But it looks like you have edited the list since then and it looks alot better. Though I have had a front strut bar and if I didnt look under the hood before driving I would have no idea it was there. I would list it as a bling mod.

For future reference, these were some things that were unclear (to me) but ARE illegal (removed above):
PnP Intercooler Elbows - Interpretation that this is an intercooler mod

Intercooler Hose - Another intercooler mod

PnP Turbo - Illegal turbo modification

Weight removal - can't remove sound deadening, radio, or speakers. Also, I had read somewhere that wagon owners could replace their back seat with an STi backseat - lighter because it doesn't fold. Is this legal?

PnP Throttle Body - I'm still not sure on this one, but since no one said it IS legal, it goes in the illegal list. I'm not sure because I would think this would fall in the realm of an intake (although now that I think about the rules I believe intake mods were very specific, not anything goes) If no one clarifies this for me I'll search for it later

As was already mentioned the verbage in the rules is pretty well clarified now. On a WRX or STI in ST* you can change whatever you want in the intake along the path up to the turbo inlet except for the MAF sensor. Since the turbo, intercooler, piping and throttle body is beyond the turbo compressor inlet in the air-flow of the engine none of it can be touched.

You cannot change or remove the rear seat in ST. You could for instance have them recovered in leather as a comfort and convenience item but you can't change the actual seat.

You also cannot remove the roof rails from a wagon in ST unless something has changed that I don't know about.

As far as suspension bushings go the ones you eventually want to hit are:

Front and rear bushing on the rear trailing arm.
Control arm bushings in the front.
If you aren't going to use adjustable lateral links replace the inner and outer bushings on the stock lateral links.

Pretty much all of those suck to do, a lot of labor for relatively little return so they'd be just about the bottom of my list.

I guess it should be mentioned that parts bin shopping for pretty much any part of the car is legal. That means that you can pick the stock turbo with the least play and best tolerances, pick the set of rods that is actually exactly the same weight, pick the set of pistons that are the same weight, etc. Balancing isn't legal by typical machinging methods but it is legal by parts bin swapping and can make a measurable difference. We also inherit the stock rules for engine. First factory overbore is legal up to .020", any thermostat.

Actually, I'm pretty sure you CANNOT remove the roof rails on the wagon. IIRC, they were standard equipment, not an option, in the United States. So you have to keep them.

Edit: as usual, my spouse/co-driver is faster than me! D'oh!

Specific suspension bushings worth mentioning- the rear transverse link (front control arm) bushings- either Group N or Whitelines one that adds a smidge of additional positive caster- both much stiffer than the oe ones.

In the rear- lateral link bushings- unless you've upgraded to adj ones as these will have firmer bushings already- Grp N or a couple of poly choices as well.

Trailing links- front (housed in the actual link) and rear- actually housed in the rear knuckle- again Grp N or a poly aftermarket.

Might have been mentioned (ddin't see it), but a relatively new allowance has to do w/ the way the strut is mounted to the knuckle. This new allowance allows the holes to be optimized to gain neg camber or even slotted.

...
Rear pillow ball upper mounts and adjustable lateral links are a legal combination. IMO, that's the way to go, simple and easy changes to rear camber and toe are priceless.
...

Phil, has there been any clarification that the rear upper strut mount can be changed to a pillow ball if you have adjustable lateral links? I could see that GroupN mounts that only change the bushing material would be allowed. The allowance for a pillow ball mount is:
"Any type of bearing or bushing may be used in the adjustable camber plate attachment to the strut" but the adjustible camber plates aren't allowed with adjustable lateral links.

If I'm wrong, can I replace the lateral links with adjustable links as long as they are set to factory length? Or how about light-weight lower links with camber plates?

"Any type of bearing or bushing may be used in the adjustable camber plate attachment to the strut" but the adjustible camber plates aren't allowed with adjustable lateral links.

I second Phil. Non-adjustable pillow ball tops and adjustable lateral links are legal. You just cannot have 2 forms of camber adjustment. It does not matter how you have the lateral links "set" as long as the tire tread is not visible looking down ( plumb ) with the widest point of the fender. I.E. tires not sticking out.

The way Phil described is the most user freindly when it comes to adjustment.

my .02

While were on the subject of ST rules, can we talk about how the new allowances can be used to fullest?
Are there any benefits I might realize by hacking fender liners or using custom designed strut ear/flanges where they attach to the hub/spindle?
Grounding kit? Pure rice or something to it?

If you've got a camber plate, or camber bolts, in back then you are stuck with stock lateral links not just stock length ones.

On the WRX at least the advantage of the new fender liner rule is that I'll never have to go to the dealer to pick up another one if a cone tears one apart again. Big help on other cars like the Civic though.

Strut ear flanges. Basically actually allows struts that were fairly radically different than stock like the ZZYZX or ones that are only a bit different from stock like Tein, JIC, KW, etc. which were of questionable legality in the past at least according to some. My math and the model I built says that you can in fact change the dynamic camber curve by changing the static angle of the strut, others disagree with me. Benefit of that would be hard to figure. You can also gain tire clearance between the strut and the inner edge of the tire allowing for wider tires to be fitted (on the WRX\STI the trailing arm becomes your inner limiter instead of the strut when using the ZZYZX ear design).

Grounding kit is IMO rice, I've done darn near everything I could to take weight out of the car why would I intentionally add 5 pounds of wire back in?

Grounding kit is IMO rice, I've done darn near everything I could to take weight out of the car why would I intentionally add 5 pounds of wire back in?

While most are FORM rather than function....simply running a few ounces of wire from the batt to body, batt to engine, from that side of the engine to the other, and from the engine to the body...it does make a rather large difference in overal consistancy of how the car runs/drives/performs. It may not show a gain on a dyno or an autox run back to back....but it does help the car run better overall.

You just dont need 5 lbs of wire to do it...all you have to do is take some 14 guage and a few connectors...bam. Done. Who cares about looks?

seat-time!!!!

2nded.

http://www.autocross.com/evolution

--kC

3rded.

Really seat time is more important than EVERYTHING else on the list, and by a wide margin. Until you can run competitive ST* times in a stock legal car on street tires there's really no point in spending thousands on mods. If you happen to have a mod on the car already, great. I've seen many people trophy regionally in STX with stock-legal WRX's on street tires.

In general, the things on your mod list that most affect autox times are the tires, shocks, alignment, and sway bars. All the other stuff is less important. Power and (I'll get flamed for this) weight mods in particular don't really help a lot at autox. They might make measurable differences at drag races but most autocrosses don't look like drag races... Tires I'd absolutely put at #1 with no qualms. The other 3 things are more debatable. Perhaps a good alignment next, if for no other reason than to keep from killing the fronts with low camber.

--Kevin H.

Oh snap! I just read the new fenderliner rule. Nice.

My math and the model I built says that you can in fact change the dynamic camber curve by changing the static angle of the strut, others disagree with me. Benefit of that would be hard to figure.

I have only thought about it in my head, but did you find that the longer the shorter the ears the more negative camber gain through compression and vise versa? Actually giving you a "worse" camber curve with long ears?

If you've got a camber plate, or camber bolts, in back then you are stuck with stock lateral links not just stock length ones.
...


Why do you say that rear pillowball mounts are legal with adjustible lateral links? The only allowance for rear pillowballs is with camber plates.

This is exactly what I was looking for. Thank you! :D

I have only thought about it in my head, but did you find that the longer the shorter the ears the more negative camber gain through compression and vise versa? Actually giving you a "worse" camber curve with long ears?

At least in the model I built if you have longer ears in the rear the car actually goes more positive on camber as compression occurs than it would in a stock configuration. So for those who like to run big amounts of rear camber this would change things one way and for those who like only a little bit of rear camber it changes it a different way. Like I said though other people have put together models and say that the dynamic camber curve doesn't (and can't on a strut based car) change and I certainly wouldn't call myself a suspension expert so I could easily be wrong. The software I was trying to model the car in was a demo version that I was trying to learn how to use and it was last winter when I did it so I don't even have a computer with the results anymore.

Why do you say that rear pillowball mounts are legal with adjustible lateral links? The only allowance for rear pillowballs is with camber plates.

If it is not a camber adjustment method (and a fixed pillow-ball without slotting the mounting holes is certainly not an adjustable item) then it is a shock mount which is open via 14.5.B.

If it is not a camber adjustment method (and a fixed pillow-ball without slotting the mounting holes is certainly not an adjustable item) then it is a shock mount which is open via 14.5.B.

OK, thanks for the clarification.

Never thought much about the orientation of the holes/flanges in the rear, but that could be pretty advantageous getting the exact camber you want by it's arrangement.

In the front, just looking at the difference between the wagon and sedan flanges illustrates clearly the advantage of getting the best orientation. A wagon strut on a sedan will add close to .5 degrees of addtional static neg camber- the other way around a loss of .5 degrees.

Wow, nice thread. I'm glad I stumbled across this with search!

Wow, nice thread. I'm glad I stumbled across this with search!

Thanks for bumping up this "shopping list" for me Zuffy. :P

Should be part of the Autox Super Thread sticky.......Mod?

Thanks for bumping up this "shopping list" for me Zuffy. :P

Hehehe, isn't NASIOC great! Oh, yah sticky this thread please.

So I'm guessing my 4 point h brace and rear subframe locks are illegal?

I'm afraid that the answer is yes

Are aftermarket up-pipes still legal with the new "clarification"? (for the 2.0liter wrx)

(have never seen a high flow cat aftermarket uppipe)

--
Brian

Are aftermarket up-pipes still legal with the new "clarification"? (for the 2.0liter wrx)

(have never seen a high flow cat aftermarket uppipe)

--
BrianI am pretty sure I remember someone making one. Random tech or something? Certainly not easy to find.

john

I am pretty sure I remember someone making one. Random tech or something? Certainly not easy to find.

john

http://www.xcceleration.com/itemdetails.cfm83.htm

A steal at $420! Plus, although I think random tech sells EPA-certified cats, I'm pretty sure the high-flow units they put in most of their performance parts are not certified. Most aftermarket high flows are not. I believe you'd have an EPA serial # stamped on the cat if it was legit.

Guess it depends on which of the 50 interpretations of the new rules is the right one.

I'm afraid that the answer is yes

off they come!

off they come!

Be forewarned that installing/removing Whiteline's rear subframe locking bolts will dramatically affect rear toe settings.

I made a quick update to add in that even with a cutout, still need to retain one cat no further back than 6" of end of last oem cat. I see some more recent comments about a new Fastrack with updates to the cats ruling? What changed exactly?

*edit* just read this posting - answers my question:
http://forums.nasioc.com/forums/showthread.php?t=1309156

note - since a cutout must be after one cat, I don't know how much benefit this will really be to a street driven STX car, since most likely this will just be adding weight since a full exhaust will be on the car still, and I would think exhaust flow gains would be minimal AFTER the cat. Should I remove this from the list, or are there some legitimate top-caliber STX 2.0L WRX's using a cutout to be competitive? If the car is a trailer queen I suppose the exhaust could exit just behind the driver (assuming sound limits are met), getting rid of the weight of the last few feet of the exhaust system.

Also noticed there was still a reference to the removal of wagon roof rails - this is ILLEGAL, since there was no option to have a roof rail delete from the factory.

Last comment, I am sure I am missing some various bushings and esoteric suspension linkages/components. If anyone would be so kind as to send me an exact and thorough listing of any that I am missing along with subjective priority, I will add it to the original list. I started looking through some schematics to trace everything down and got bored - I know someone has this info in their head already...

Thanks

Do you want links of where to get the bushings too? Also, in some cases there are softer bushings and harder bushings; since folks that would be doing this would likely be going for national prep level (i.e. ALL mods) I'm assuming the stiffest available bushings? :)

-Biggly

http://www.xcceleration.com/itemdetails.cfm83.htm

A steal at $420! Plus, although I think random tech sells EPA-certified cats, I'm pretty sure the high-flow units they put in most of their performance parts are not certified. Most aftermarket high flows are not. I believe you'd have an EPA serial # stamped on the cat if it was legit.

Guess it depends on which of the 50 interpretations of the new rules is the right one.
I didn't see a bung for the EGT sensor on that catted uppipe.

It's there. Here's the uppipe from another angle and cheaper source:
http://www.wrxevolution.com/exhaustcbwrx.asp

Do you want links of where to get the bushings too? Also, in some cases there are softer bushings and harder bushings; since folks that would be doing this would likely be going for national prep level (i.e. ALL mods) I'm assuming the stiffest available bushings? :)

-Biggly

Thanks for the offer of links where to get them - feel free to post them. Added a clarification about bushings - upgrade = harder, and note that the ratio of metal/non-metal cannot increase.

Update to original list: I looked through all the thorough postings and I believe I sorted it out and listed all the bushings I could find. Mostly listed under the "Low Priority" section, with the exception of offset front control arm bushings since they give a caster gain. Also minor reshuffling and additions. Also made a reference to recent Fastrack rule "clarification" which leaves some debates brewing about the legality of removing cats. Make your own interpretation....

Let me know if anything is still incomplete. There may still be some missing bushings and I have briefly looked, but haven't seen a reference to see if there is a minimum termination point for the exhaust (e.g. 6" behind driver's seat or something like that).

...how about drive the car...and learn to drive before you mod the crap out of it.

...how about drive the car...and learn to drive before you mod the crap out of it.

that's why it already says this right up front:
DISCLAIMER: THROWING MONEY AT YOUR CAR WON'T MAKE YOU FASTER UNTIL YOU CAN PUT THE POWER TO THE GROUND SMOOTHLY. This list is only to illustrate what COULD be done to your STX WRX. National level winners have won with far less than everything on this list - BUT GREAT DRIVING SKILL. DRIVING SKILLS WILL ALWAYS HAVE THE GREATEST BENEFIT!

Specific suspension bushings worth mentioning- the rear transverse link (front control arm) bushings- either Group N or Whitelines one that adds a smidge of additional positive caster- both much stiffer than the oe ones... Trailing links- front (housed in the actual link) and rear- actually housed in the rear knuckle- again Grp N or a poly aftermarket....

Do you want info on where to get the bushings too? Also, in some cases there are softer bushings and harder bushings; since folks that would be doing this would likely be going for national prep level (i.e. ALL mods) I'm assuming the stiffest available bushings? -Biggly

Yes Biggly, please help! I'm looking for GC specific bushings (STS car). Super Pro has a complete lateral link bushing kit... never heard of them though and I haven't found a GC specific kit from Whiteline (maybe they're interchangeable?). The Whiteline control arm rear/transverse offset bushing looks like a winner, would you recommend replacing the balljoints (MOOG sells em) and what about the front control arm bushings.. worth it? The other missing piece is the rear/knuckle trailing arm bushings, can't find them.... (super pro makes the fronts though)...

Yes Biggly, please help! I'm looking for GC specific bushings (STS car). Super Pro has a complete lateral link bushing kit... never heard of them though and I haven't found a GC specific kit from Whiteline (maybe they're interchangeable?). The Whiteline control arm rear/transverse offset bushing looks like a winner, would you recommend replacing the balljoints (MOOG sells em) and what about the front control arm bushings.. worth it? The other missing piece is the rear/knuckle trailing arm bushings, can't find them.... (super pro makes the fronts though)...
http://www.rallispec.com/prod_mount.htm
That probably has some/most of the Grp N mounts...

EDIT: ok sorry I found the ST* exhaust database thread...

can someone advise on the exhaust (uppipe and downpipe listed as high priority), I've read through the old exhaust clarification of 2007 threads but haven't really found a consensus, I know going all high-flow will work, but it's out the the question for me - too much $$$.

So must the up/dp be changed to include all 3 cats (high-flow), or are there other combos people have found to work. Basically I'm trying to get up to speed with where everyone is at on this issue a year past the time most of those discussions occurred.

I'm debating what to do with my helix high flow catted dp and catless (and EGT bungless) uppipe; change to STX legal, go back to stock, only do local events where no-one in STX cares...

Low priority and priority appear to be almost completely flipped.

Maybe some of them...

Brake fluid as a priority? No performance difference with the heat generated during an autox run.

Maybe some of them...

Brake fluid as a priority? No performance difference with the heat generated during an autox run.

I’m not so sure about this, ever try left-foot braking to maintain boost?

I know from experience the heat generated is plenty enough to boil old, i.e. watery fluid and cause fade. This happened to me just after I bought my wrx, I wasn’t left-footing at all at the time and this was a relatively small/slow course on a cool day. I have no way of knowing exactly how old the fluid was (possibly original - hopefully not but wouldn't be surprised - on a 45k mile ’03 in ’07) so I can’t say for sure that “high quality” fluid is required as long as you’re changing it out regularly, but I think it could be a concern.

I’m not so sure about this, ever try left-foot braking to maintain boost?

I know from experience the heat generated is plenty enough to boil old, i.e. watery fluid and cause fade. This happened to me just after I bought my wrx, I wasn’t left-footing at all at the time and this was a relatively small/slow course on a cool day. I have no way of knowing exactly how old the fluid was (possibly original - hopefully not but wouldn't be surprised - on a 45k mile ’03 in ’07) so I can’t say for sure that “high quality” fluid is required as long as you’re changing it out regularly, but I think it could be a concern.
How do you know the fluid was boiled?

I have heard of LFB'ers having brake issues (vacuum assist?), but not because of fluid fade.

How do you know the fluid was boiled?

I have heard of LFB'ers having brake issues (vacuum assist?), but not because of fluid fade.

At that time I wasn't LFB'ing at all.

I had noticeable fade toward the end of my runs and wouldn't have attributed it directly to the fluid at the time, but having since changed fluid (and for a time nothing else brake related) I haven't had anything like it happen again. I'm pretty sure it actually was fluid fade, what I can't say for sure is the condition of the fluid at the time, must have been somewhere between 100% fluid and 100% H2O :lol:.

Really I wonder how bad the fluid could have been, like it said worst case it had 4yrs/45kmiles, if the 30k maintenance was done :confused: it would have only been a couple years old.

At that time I wasn't LFB'ing at all.

I had noticeable fade toward the end of my runs and wouldn't have attributed it directly to the fluid at the time, but having since changed fluid (and for a time nothing else brake related) I haven't had anything like it happen again. I'm pretty sure it actually was fluid fade, what I can't say for sure is the condition of the fluid at the time.
What pads were you on?

What pads were you on?

Prolly OEM

I'd bet that was your problem and not the fluid.

I had loss of vacuum assist on the brakes, a non-LFB driving setup. I used a T-fitting to run a vacuum canister located inside the front bumper wheel well. It worked exceptionally for when I was running BSP / SM. Now, switching to STU, it's been removed. We'll see if the lack of vacuum assist returns.

What about subframe-lock bolts?

I'd bet that was your problem and not the fluid.

Could be, I need to check my records on when I changed pads, I could have sworn I ran those pads a few other times after the fluid change and never had any issues.

What about subframe-lock bolts?
If it's not in the list of modifications it's not allowed. That goes for any class.

Technically you're adding metal where there wasn't before, but you're not modifying the car in any way. It's not really a bushing, it's a fastener. This is one of those things that are kind of in a grey area, IMO. But then again, the rules state that if it's not allowed you must be moved into a prepared or modified class.

But to play it safe (especially if you're going to be competing in a "real" event and not your local chapter) don't install them.

If it's not in the list of modifications it's not allowed. That goes for any class.

Technically you're adding metal where there wasn't before, but you're not modifying the car in any way. It's not really a bushing, it's a fastener. This is one of those things that are kind of in a grey area, IMO. But then again, the rules state that if it's not allowed you must be moved into a prepared or modified class.

But to play it safe (especially if you're going to be competing in a "real" event and not your local chapter) don't install them.

Ditto that. Unless the the rule book says, "The installation of subframe lockout bolts is allowed", then you can't install them legally.

The last time I was under there looking up at the subframe I think I noticed that the subframe rides on four bushings. Now those could be replaced with some other bushing as long as the amount of metal in the replacement bushing is the same as OEM. No one makes those. I've looked. You have to custom make them.

What about a catch can? As I read it in the stock rules 13.10 sub G it looks like it would be legal. Anyone have a reason not to install other than added weight?

Oh, so *this* is why I couldn't find this thread in the "Autocross" subforum.

Thanks for bumping it!

Anyone other than GrantC still looking at this?

my read is the same- catch can would be legal for ST- can't see any real down side- most of the ones I've seen are pretty light

Anyone other than GrantC still looking at this?no, not really :D

Turns out I'm still reading it. Early in the thread someone mentioned a BBK, but they have to mount to the original attachment points. What BBK's meet that criteria? Would sti takeoffs mount to the original wrx (2002) attachment points?

The original attachment points for BBKs are the two bolts that mount to the hub. If you don't need to brace it, or create new holes, or find a different way to attach it other than using the stock mounting locations, you're good to go.

--kC

Turns out I'm still reading it. Early in the thread someone mentioned a BBK, but they have to mount to the original attachment points. What BBK's meet that criteria? Would sti takeoffs mount to the original wrx (2002) attachment points?

4-pot, 2-pot brakes work too. They will also be allowed under UD/BD if I end up doing ESP. :p

4-pot, 2-pot brakes work too. They will also be allowed under UD/BD if I end up doing ESP. :p

Are you sure about that? If that reasoning held, one would be able to swap in the EJ255, which would then bump them into BSP. Right?

I messed around with UD/BD-ing my Miata, but it's been years.

John

Are you sure about that? If that reasoning held, one would be able to swap in the EJ255, which would then bump them into BSP. Right?

I messed around with UD/BD-ing my Miata, but it's been years.

John

You exactly right, in SP you can swap in the EJ255 since 02-07 WRX are on the same line. In fact, to be competitive, you pretty much *have* to.

Only the 08/09 WRX were moved to BSP, because of the new turbo in the 09 WRX.