STU guys check in. Set ups

[WRX8XB]

Originally Posted by justint5387

Oh cool, what wheel is 18x10.5 +50?

These specs will not work on a GD, not even close. The GD lacks inboard clearance that the new cars have.

Fitting a 265 on a GD is possible, but it's tough without pulling the rear fenders.

Some coilovers have a good bit more inboard clearance than others, some have very ****ty inboard clearance.

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[WRX8XB]

Originally Posted by Panza

Wheels specs are 18x10.5+50
Tires are Yokohama A052 265/35R18

The 10.5's are to get the Yoko's stretched, but you could run 18x10's (+45) with this set up without issue if that's easier to find wheels. I personally searched tire rack for Mustang rear wheels as they were cheaper.

Is this on stock struts? Coilovers normally have rubbing issues with that high an offset and 265s.

[Panza]

Originally Posted by WRX8XB

Is this on stock struts? Coilovers normally have rubbing issues with that high an offset and 265s.

My STI IS on stock struts actually. The lower half of the shock sits above the tire of the wheel. I hadn't thought about a coilover body interfering with the wheel clearance.

[WRX8XB]

Originally Posted by Panza

My STI IS on stock struts actually. The lower half of the shock sits above the tire of the wheel. I hadn't thought about a coilover body interfering with the wheel clearance.

that makes sense. Stock shock GR/GV can fit some meats.

[justint5387]

Originally Posted by WRX8XB

These specs will not work on a GD, not even close. The GD lacks inboard clearance that the new cars have.

Fitting a 265 on a GD is possible, but it's tough without pulling the rear fenders.

Some coilovers have a good bit more inboard clearance than others, some have very ****ty inboard clearance.

What's the widest possible on the front on a GD?

Thinking if running reverse stagger with same overall diameter tires

[jesup16]

Originally Posted by justint5387

What's the widest possible on the front on a GD?

Thinking if running reverse stagger with same overall diameter tires

If you play the offsets right, I've seen 10's and 10.5's fit up front... you'll definitely have to be selective with wheels, offsets, etc

[WRX8XB]

Originally Posted by justint5387

What's the widest possible on the front on a GD?

Thinking if running reverse stagger with same overall diameter tires

The coilover of choice, camber, etc will play a big role.

18x10 +35mm can fit up front without too much headache the rear is tougher.

[T-37]

Originally Posted by WRX8XB

The coilover of choice, camber, etc will play a big role.



18x10 +35mm can fit up front without too much headache the rear is tougher.

This, I run 275/35/18 re71s on 18x9.5 (SM). My RCEs are out for rebuild right now. I rub pretty heavily in the rear, but switching to my backup Stance SS+ (inverted monotube) while the RCEs are being serviced I gained enough clearance to not rub in the rear.

[Splash]

FYI, I run 18x9.5 et45 PF-01's with 265/35-18 A-052's all around on my '04. Rear lips are rolled, but that's it. KW or AST coilovers. I run a spacer up front, 5mm I think, but I don't NEED to.

Looking into a staggered setup myself to get 18x11's up front.

[subydude]

Originally Posted by Splash

FYI, I run 18x9.5 et45 PF-01's with 265/35-18 A-052's all around on my '04. Rear lips are rolled, but that's it. KW or AST coilovers. I run a spacer up front, 5mm I think, but I don't NEED to.

Looking into a staggered setup myself to get 18x11's up front.

11's won't fit up front in STU trim based on the rear pinch weld in the fender. 10's are the easy choice it seems, and 10.5's might work, but it's gonna be a lot of variables to make work without cutting tires down regularly.

[Thorium06]

I ran 18x10.5, I think 45 offset with spacers up front in STU on my 05, those fit fine. The problem with 11s is the offset on them becomes too low to fit. The rear can fit a 10 fine if you have the inboard clearance. If I was still in that class I would try 285s on 18x10.5 front and 18x10 rear.

[Panza]

I have a tuning question... What kind of a tune can I get done for the STI?

My head gasket has a leak (internal coolant leak) and so I'll be sending the car out to have that replaced.
While I'm at it, I'm thinking about replacing some tired parts on the car. Intake, Equal Length Headers, Downpipe which will obviously need a tune.

Any tips for the head gasket and light build? Thanks

[Thorium06]

Originally Posted by Panza

I have a tuning question... What kind of a tune can I get done for the STI?

My head gasket has a leak (internal coolant leak) and so I'll be sending the car out to have that replaced.
While I'm at it, I'm thinking about replacing some tired parts on the car. Intake, Equal Length Headers, Downpipe which will obviously need a tune.

Any tips for the head gasket and light build? Thanks

As far as the head gasket and light build question, in STU the headgasket and engine itself must remain OEM, even the heads may only be decked to the minimum allowed in the service manual.

The headers and downpipe can give significant gains within the STU allowances and would be worth doing. I've had mixed results with intakes and found at least on the GD that the OEM airbox with a drop in filter was better and made more consistent power during a run. The downpipe allowance has very specific cat requirements, especially with placement, make sure whatever brand you're looking at is compliant with the allowance.

[Panza]

Originally Posted by Thorium06

As far as the head gasket and light build question, in STU the headgasket and engine itself must remain OEM, even the heads may only be decked to the minimum allowed in the service manual.

The headers and downpipe can give significant gains within the STU allowances and would be worth doing. I've had mixed results with intakes and found at least on the GD that the OEM airbox with a drop in filter was better and made more consistent power during a run. The downpipe allowance has very specific cat requirements, especially with placement, make sure whatever brand you're looking at is compliant with the allowance.

Interesting that the GD performs best with the stock intake.
I thought the OEM downpipe has two catalytic converters and two parts to it... how do I stay compliant to the rules this way? Do I just settle that one of the cats are removed and there's one HFC left over?
And as for the tune, does the tuner just adjust everything else except the boost levels?

[Thorium06]

Originally Posted by Panza

Interesting that the GD performs best with the stock intake.
I thought the OEM downpipe has two catalytic converters and two parts to it... how do I stay compliant to the rules this way? Do I just settle that one of the cats are removed and there's one HFC left over?
And as for the tune, does the tuner just adjust everything else except the boost levels?

The current ruleset is quite different from where it was for most of this thread with regards to "boost tables" ect. Currently you are allowed to tune anything on an OEM ecu, and you are even able to swap out boost controllers.

A single high flow cat may replace two cats, and the inlet of which must be no further downstream than 6 inches from the exit of the final cat.

Here is a link to the current rulebook:

https://cdn.connectsites.net/user_fi...pdf?1649867026

[blindstuff]

This thread is a great resource.

Recently quit racing motorcycles and looking to get a new fix. Just tried my first Auto-X on the GR STI despite having it for about 5 years now. Humbling experience, I was way overdriving and slow AF.

I'm running in STU with stock suspension and wheels on PS4S' (fresh bushings all around and recently aligned - max camber 0 toe), I want to do a few more events in this config, but would like to start planning a dedicated wheel /tire combo.

Having read here, it seems most people are going with wider wheels. My first thought was to go with 18 x 8.5 on RT660s 245/40. Is there really that big of an advantage to go with a 18 x 9.5 (motegi mr145 +45mm) with 265/35 considering the extra cost and weight being added? I don't want to modify fenders to get them to fit.

[Butt Dyno]

Originally Posted by blindstuff

Having read here, it seems most people are going with wider wheels. My first thought was to go with 18 x 8.5 on RT660s 245/40. Is there really that big of an advantage to go with a 18 x 9.5 (motegi mr145 +45mm) with 265/35 considering the extra cost and weight being added? I don't want to modify fenders to get them to fit.

IMHO - if you are new, you are still going to have fun and the ability to be pretty competitive - especially locally - on 245s. Don't worry about optimizing the stuffing out of it from the get-go. 265s should be faster, for sure, but you can still get up to speed just fine on a good set of 245s.

[blindstuff]

Originally Posted by Butt Dyno

IMHO - if you are new, you are still going to have fun and the ability to be pretty competitive - especially locally - on 245s. Don't worry about optimizing the stuffing out of it from the get-go. 265s should be faster, for sure, but you can still get up to speed just fine on a good set of 245s.

Thanks. I'll be running the 245 PS4S for a few more events.

Once I'm ready to buy a dedicated wheelset I'll revisit 245 vs 265.

[Thorium06]

FWIW, the 285 is easier to fit than the 265 due to the height differences. 285 on an 18x10 or 10.5 would be what I would do, especially with a GR

[Craig_B]

Originally Posted by blindstuff

Thanks. I'll be running the 245 PS4S for a few more events.

Once I'm ready to buy a dedicated wheelset I'll revisit 245 vs 265.

I was driving the GD STi in your group last weekend. My advice would be to get as wide of tire as possible for autocross. I was on my set of 235/45/17 last weekend. My stock rims have 245/40/17's and I can tell the difference. My next set will be 255's on wider rims. The M3 that dominated STU was on brand new, very wide RT660's.

[blindstuff]

Originally Posted by Craig_B

I was driving the GD STi in your group last weekend. My advice would be to get as wide of tire as possible for autocross. I was on my set of 235/45/17 last weekend. My stock rims have 245/40/17's and I can tell the difference. My next set will be 255's on wider rims. The M3 that dominated STU was on brand new, very wide RT660's.

Beautiful GD man! Cool to find you here. Are you going to Gulf Coast AutoX in June?

That M3 was something else, I get what you mean, thanks for the input. I've gotten so many differing opinions that I think the course of action is to improve as a driver for a few events and then figure out if I can fit 265s without rolling the fenders.

[blindstuff]

Originally Posted by Thorium06

FWIW, the 285 is easier to fit than the 265 due to the height differences. 285 on an 18x10 or 10.5 would be what I would do, especially with a GR

Sorry to sound stupid, but I don't get how this would be easier than a 265 on 18 x 9.5. What am I missing?

[Butt Dyno]

Originally Posted by blindstuff

Sorry to sound stupid, but I don't get how this would be easier than a 265 on 18 x 9.5. What am I missing?

The 285-30-18 is a shorter tire than the 265-35-18

[Thorium06]

Originally Posted by Butt Dyno

The 285-30-18 is a shorter tire than the 265-35-18

Correct, the 285 is significantly shorter than the 265, and if you are ok with rear poke, you could get away with more wheel out back too than the 9.5 wide. With STU legal fenders and suspension, I ran 285 A7s on 18x10 +38s at Nationals in 2019 with a bit of rear poke. It didnt rub, even when street driving. If I were still in STU I'd strongly consider than same fitment.

[Craig_B]

Originally Posted by blindstuff

Beautiful GD man! Cool to find you here. Are you going to Gulf Coast AutoX in June?

Unfortunately not. I haven't made the trip over there in over a year now. Life is just too dang busy and I prioritize track days over autocross. I can only get so much weekend time away from the wife and kids.

Maybe in the fall, I'll try to do an event or two over there. With gas so ridiculous, autocross just makes more sense than burning $150 driving around Sebring.