Street Touring Hatchback (STH) discussion/setup

[DerHase]

Was the bump steer noticeable to you while driving?

Yes. The car feels "odd" if nothing else.

These cars hide it pretty well between all the bushings and heavily over-assisted steering.

The bigger problem is the stupid tire wear due to the overly-active toe. I don't expect it to be quite this bad on a considerably stiffer suspension, but any kind of stock springs or lowering springs are soft enough rate that you're using all of +/-1.5in of wheel travel on a pretty regular basis. Every little bump, dip, pothole, turn, etc the toe is changing wildly.

No alignment toe settings will fix this.

Now some is likely from spinning the inside tire on corner exit on track, but I’ve never gotten wear like this before. Is it from more camber? Potentially yes. So take this FWIW. Other factors CAN be at play.


My tire wear at stock ride height with 034 camber mounts + offset bushings was REALLY good. I’ve been chasing suspension problems ever since deviating from that formula. More camber would be great but for a dual use car it worked really really well.

I think it might be worth playing with suspension packers to extend the bump stops closer to contact for autocross, etc. it’s basically supplemental spring rate that’s easily removable if need be. And cheap to experiment with. If I do go back to stock or stock-ish springs I plan on playing with this idea.

 

[DerHase]

I know I can do camber plates and offset LCA bushings, but I would think ball joints and camber plates at the same time would be a no go, altering camber in two different ways.

I'd assume the ball joint is considered part of the lca assembly.

Not sure how I missed this the first time around. Whiteline, 034, and Superpro ball joints are all illegal for STH regardless of what else you're running.

They alter roll center. They're not even allowed in Street Prepared (or at least weren't a couple years ago, I know there were some letters pending at one point in time).

Edit: still not allowed even in SP:

 

[GTIfan99]

Not sure how I missed this the first time around. Whiteline, 034, and Superpro ball joints are all illegal for STH regardless of what else you're running.

They alter roll center. They're not even allowed in Street Prepared (or at least weren't a couple years ago, I know there were some letters pending at one point in time).

Edit: still not allowed even in SP:

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I'll have to see how much I can get from just TTS arms then. If less than -2 camber total, I'll just do offset lca bushings and Eurosport camber kit again. I'll buy the pre-assembled version, drilling them out was a pain last time.

Edit TTS won't work, they require the TTS ball joints.

At least that clears up the path I need to take. Eurosport and offset LCA.

 

[Jmitchell4873]

Not sure how I missed this the first time around. Whiteline, 034, and Superpro ball joints are all illegal for STH regardless of what else you're running.

They alter roll center. They're not even allowed in Street Prepared (or at least weren't a couple years ago, I know there were some letters pending at one point in time).

Edit: still not allowed even in SP:

View attachment 301932

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If I cared more about being competitive, I would have built my car to the rules. I'll just concentrate on having fun and being uncompetitive in XSA where they allow pretty much anything.

If mine or my son's skills improve to the point where being competitive is more important, I can pull some parts off to comply with STH rules.

Street prepared seems like a weird class to me. I guess I don't understand SCCA's reasoning behind running Hoosiers, but not allowing the suspension changes to take full advantage of the tires.

 

[Maiden69]

Not sure how I missed this the first time around. Whiteline, 034, and Superpro ball joints are all illegal for STH regardless of what else you're running.

They alter roll center. They're not even allowed in Street Prepared (or at least weren't a couple years ago, I know there were some letters pending at one point in time).

Edit: still not allowed even in SP:

View attachment 301932

View attachment 301933

Ain't the comment in H contradictory to the statement you highlighted? C. don't allow changes in geometry, but H. allows for camber kits, which include ball joints.

 

[scrllock]

Ain't the comment in H contradictory to the statement you highlighted? C. don't allow changes in geometry, but H. allows for camber kits, which include ball joints.

H.4: All bushings must meet the requirements of Seciton 15.8.C (the one he highlighted). You can only use a balljoint that doesn't change the pickup point, which means no roll center correction.

 

[scrllock]

Ain't the comment in H contradictory to the statement you highlighted? C. don't allow changes in geometry, but H. allows for camber kits, which include ball joints.

typically "geometry" means something different than "alignment." You can change alignment all day, but you can't change where on the chassis or spindles things connect to (geometry).

 

[Maiden69]

H.4: All bushings must meet the requirements of Seciton 15.8.C (the one he highlighted)

Ok, I thought it was a different one, as the one highlighted title is 15.5.C

 

[krs]

FL scca events you don't need to worry about that though. So no problem.

 

[GTIfan99]

I think ST and SP should set max camber limit and not worry how you get there, as long as it's safe.

 

[Jmitchell4873]

I think ST and SP should set max camber limit and not worry how you get there, as long as it's safe.

That would level the playing field more than any of the rules they have now.

-2.1f, -1.8r wasn’t enough for me this past weekend. 15 runs on the autoX course showed me that I definitely need to dial in some more in the front and maybe even try to squeeze some more in the rear if the shocks have a little more room for the tires.

I think these already have some tread splice issues starting to show too.

 

[krs]

That would level the playing field more than any of the rules they have now.

-2.1f, -1.8r wasn’t enough for me this past weekend. 15 runs on the autoX course showed me that I definitely need to dial in some more in the front and maybe even try to squeeze some more in the rear if the shocks have a little more room for the tires.

I think these already have some tread splice issues starting to show too.
View attachment 301980

My cracks are worse than that.

Not worth the worry for autox in my opinion. ¯\_(ツ)_/¯

 

[GTIfan99]

My cracks are worse than that.

Not worth the worry for autox in my opinion. ¯\_(ツ)_/¯

Agreed, but they killed my track plans last year. No way I'm driving 150 mph on a tire like that.

 

[DerHase]

Should a dedicated "XA" thread be made?

My fastest run from yesterday:

And my codriver got me by 0.1 sec:

Looking forward to going back and forth with data this year. Need to overlay squiggly lines to compare more. Really need to get a Racecapture unit as that would speed this up greatly. Might sell my Catalyst since that would cover the cost and then work for both track and autocross.

Comparing those two runs, I *think* the car seems to do better cutting distance on the longer sweepers, which Logan did a lot more of.

First time on RE71RS, they're really good but looking forward to next time since this was their first real heat cycle.

The car is in XA due to the 034 ball joints and hood vent. Otherwise legal (with the PCV being legal-ish).

 

[GTIfan99]

I was at GRM $2024 challenge yesterday. They opened a class for cars over $2024. Every Mk7 that ran put on a smoke show.