Ideal toe in for IRS buggies like Class 1?

Scott_F

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In your opinion, what is the most desirable toe in number throughout the travel on an IRS with semi-trailing arms?
 
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He is asking about toe-in or toe-out on the rear of an IRS car. It is all going to depend on your car and driving preferrence. It will fall somewhere between 1/4 in and 1/4 out; any more than that and you be scrubing speed, especially in a limited car like a 1600. I run mine at 0.
 

DBMETALWORX

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We run .125-.250 toe in.. 1.5 degrees camber.
 

FABRICATOR

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With monolithic semi-trailing arms you can only have a range, not a number. I desire to avoid toe-out. :)
 

Scott_F

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Thanks for the comments guys.

On a semi-trailing arm, the camber and toe change throughout the travel.
I just checked the toe on my design. When the arm is level, it is at zero toe.
As it progresses to bump, it gradually increases to .125" toe in.
As it progresses to droop, it gradually increases to .125" toe in.
If it continues to droop, the toe in continues to increase.
From bump to droop, the camber goes from negative, to zero, to slightly positive.

I think for my travel range I have ideal geometry. Any further comments?
 
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