SCCA F-Street Setup. What's Everyone Done so Far?

TeeLew

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You gave up rear footprint. Even if the tire construction is more pushy, there's a lot to be said for contact patch area.
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Norm Peterson

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I went from 275 35 R18 front & 285 30 R 18 rear RE-71r tires to square 275 40 R18 Yokohama A052 tires and just ran my first event.

Surprisingly, it made the car EXTREMELY tail-happy and I softened my strano rear swaybar from full stiff to the middle setting at lunch. In prep for next week, I put the rear bar to full soft.
I'm somewhat less surprised. You've added a lot of sidewall height without changing the as-mounted section width much (I'm assuming that you're still running the same wheels for both your 'before Yokes' and 'after Yokes' events. So I'm expecting a bigger change in lateral tire distortion out back than up front (compared to before).

Almost an inch more sidewall height translates to a 1" higher geometric rear roll center, which is itself an oversteer effect. The half inch added to the front geo-RC height isn't going to balance that, and load transfer through the geo-RC's happens almost instantaneously (no waiting for roll to develop).

Comparison shown with 30mm different offsets for clarity; at the same offset too many of the lines fell almost on top of each other.

TireNominal V00L06 2754018 10 vs 2853018 10.jpg



Norm
 
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Dana Pants

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Good catch on the ride height. It looks like the 265 yoko has the same tread width and is much shorter.... lesson learned for next time. (If I buy yokos again)
 

[email protected]

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Good catch on the ride height. It looks like the 265 yoko has the same tread width and is much shorter.... lesson learned for next time. (If I buy yokos again)
When you go to CAM
 

TeeLew

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Almost an inch more sidewall height translates to a 1" higher geometric rear roll center, which is itself an oversteer effect. The half inch added to the front geo-RC height isn't going to balance that, and load transfer through the geo-RC's happens almost instantaneously (no waiting for roll to develop).

Norm
After my experience with lower ride height front springs and stock rear springs/ride height, I think the effect of rake, the difference in front and rear ride height, is underappreciated. It's a powerful tool.
 

Dana Pants

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Review of Yokos Day 2: Strano rear bar set to soft.

The car was "underdamped" and perhaps getting a bit pushy. My aggressive steering inputs show I was trying to cause rotation.

I increased my Koni shocks from 2.0F 0.25R to 2.25F 2.0R and this seem to give the car the pitch & roll control it needed and put back a little spunk into the rear suspension.

I think after 3 or 4 events total I should rotate the tires front to back. and probably flip after another 3 or 4.

The course was so tight that my friend in STS hunted me down at lunch trying to give me the keys to his car. "Don't go out there with the Mustang, Its a suicide mission." Despite this I left with a big smile and PAXed 15/67. Based on that I would say these tires are a big success competitively... but also probably lighting money on fire.


Attached is a stock photo of a new Yoko and my worst Yoko after 30 runs.

New Yoko.jpg


744D268B-9C10-413F-BA50-DCD1A326BD86.jpeg
 
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AlfaFord

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Review of Yokos Day 2: Strano rear bar set to soft.

The car was "underdamped" and perhaps getting a bit pushy. My aggressive steering inputs show I was trying to cause rotation.

I increased my Koni shocks from 2.0F 0.25R to 2.25F 2.0R and this seem to give the car the pitch & roll control it needed and put back a little spunk into the rear suspension.

I think after 3 or 4 events total I should rotate the tires front to back. and probably flip after another 3 or 4.

The course was so tight that my friend in STS hunted me down at lunch trying to give me the keys to his car. "Don't go out there with the Mustang, Its a suicide mission." Despite this I left with a big smile and PAXed 15/67. Based on that I would say these tires are a big success competitively... but also probably lighting money on fire.


Attached is a stock photo of a new Yoko and my worst Yoko after 30 runs.

New Yoko.jpg


744D268B-9C10-413F-BA50-DCD1A326BD86.jpeg
 

AlfaFord

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Hi all I’m looking to find a Strano adjustable rear bar, let me know if you have one for sale or have any leads.
 

strengthrehab

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Hi all I’m looking to find a Strano adjustable rear bar, let me know if you have one for sale or have any leads.
Try contacting Sam? Hopefully your interactions with him proceed better than mine do.
 

boardkat

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Yea I will Monday but hear he’s no longer making it.
“He” doesn’t make it - Hellwig does. If Strano isn’t carrying stock any more and is unwilling to place another order, you might want to reach out to them directly. Barring that, I’ve got one collecting dust that I might be persuaded to move..
 

Dana Pants

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“He” doesn’t make it - Hellwig does. If Strano isn’t carrying stock any more and is unwilling to place another order, you might want to reach out to them directly. Barring that, I’ve got one collecting dust that I might be persuaded to move..
Please. I’m trying to foster good competition at NER.

Also, my yoko wear prediction seems true. Sitting at my desk right now gathering the courage to flip the yokos After ~7 events with a relatively harmless dual driver.

7F92556F-2804-443E-A5C6-CCF0A35B770C.jpeg
 

AlfaFord

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“He” doesn’t make it - Hellwig does. If Strano isn’t carrying stock any more and is unwilling to place another order, you might want to reach out to them directly. Barring that, I’ve got one collecting dust that I might be persuaded to move..
Hi boarkat, I'm interested, pics, condition, price? I'll PM you.
 
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