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Toe? Does a little really hurt straight line speed...

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#1
bmw251

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I am experimenting with different set ups .... With other cars like my bmw we ran 1/16 out in the front and 1/16 in in the rear..... Is this unheard of by any fast guys? Will this little truly scrub speed?

Thanks
Greg

#2
Jim Drago

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I am experimenting with different set ups .... With other cars like my bmw we ran 1/16 out in the front and 1/16 in in the rear..... Is this unheard of by any fast guys? Will this little truly scrub speed?

Thanks
Greg

 

Those numbers will have no effect on speed. We routinely run 1/16-1/8 out in the front and 1/16-1/8 in on rear.   Toe in on the front is what kills speed in my experience. 


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#3
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What Jim says


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#4
Ron Alan

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Those numbers will have no effect on speed. We routinely run 1/16-1/8 out in the front and 1/16-1/8 in on rear.   Toe in on the front is what kills speed in my experience. 

When you say 1/8"...are you using the 15" diameter of the wheel(machine) or a toe plate of 22" +/-? 

 

I ask because i saw a pretty cool hunter machine this weekend that uses a disk type contraption that clamps to the outside of the wheel but measures on roughly a 10" diameter. So 1/8" on this might be 1/4" on toe plates.


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#5
Jim Drago

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When you say 1/8"...are you using the 15" diameter of the wheel(machine) or a toe plate of 22" +/-? 

 

I ask because i saw a pretty cool hunter machine this weekend that uses a disk type contraption that clamps to the outside of the wheel but measures on roughly a 10" diameter. So 1/8" on this might be 1/4" on toe plates.

toe plates


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#6
Mark

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Ron,

 

Don't let the size of the Hunter optical targets fool you. The Hunter uses a std (22"?) length measurement for calulating toe when displaying in inches. You can also display toe in degrees which is 'length independent'. It is more difficult to calculate toe in degrees when using toe plates though.

 

Mark


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#7
davew

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What mark says


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Tom Sager

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There are some really old school guys who used a ouija board alignment tool (not the game board that comes in a box ) and they would tell you that with the amount of negative camber we run that we need some toe out to reduce drag.  


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#9
Jim Drago

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There are some really old school guys who used a ouija board alignment tool (not the game board that comes in a box ) and they would tell you that with the amount of negative camber we run that we need some toe out to reduce drag.  

 

I believe that to be VERY accurate and I am not even old school :)


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Ron Alan

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Ron,
 
Don't let the size of the Hunter optical targets fool you. The Hunter uses a std (22"?) length measurement for calulating toe when displaying in inches. You can also display toe in degrees which is 'length independent'. It is more difficult to calculate toe in degrees when using toe plates though.
 
Mark


I believe you. But the guy who had the machine sells them for a living and I'm going by what he said. But it's very possible he misunderstood the question I asked him.
Not sure what type of machine is used at TFB(local shop)but I'm pretty confident Tim has told me the measurement it uses is 15". He always comments toe plate measurement will be larger than his machine numbers by a little.

Ron

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#11
Tom Sager

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I believe that to be VERY accurate and I am not even old school :)

 

Don't kid yourself, you are getting closer to old school every day.  


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#12
Jim Drago

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Don't kid yourself, you are getting closer to old school every day.  

Sad but true :(


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#13
Keith Novak

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I think a more important question is will any increase in drag caused by toe, offset the benefits you may get from ability to corner better?

 

I've been experimenting quite a bit with my settings and can make some pretty significant changes in handling with some little tweaks to the toe.  I have it set up to really want to turn but kind of darty going straight.  Any speed I lose in a straight line is more than made up for by improved turn in speed and corner exit speed (although it does involve some extra pucker factor when braking). 

 

Similarly I did an enduro in a Nissan where they set it up with no toe front or rear for straight line speed.  I thought it handled like a pig with tons of understeer.  My second stint was right after the car was hit hard in the side which knocked some toe out into the front.  I was able to drive the car 4 sec faster than anyone had before, including myself.


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I must not be a very good driver or not at the limit , as I have ran my car with 0 toe front and rear and then the toe out front toe in rear being discussed above, and I cannot tell a difference, but then again i am comparing two different weekends when i try to tell the difference.

 

i want to go  back for a moment about the point that you will get different toe readings at the track if you use a string kit in you shop measuring toe at the diameter of the rim (15 inches) or toe plates at the track 22 inches.

 

I assume the more accurate measurement is the toe plate because it takes into account the rubber beyond the diameter of the rim?

 

What number should i use??


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Johnny D

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I guess the larger dia would be more accurate from size, but the rubber/tire I'm not sure about accurate.

The wheel should be accurate.

 

Has anybody come out with tow plates (I guess there disks) with the tapes going through the spokes of the wheel and the plates are on the wheel and not the tire ?

Assuming there not disks, etc. in the way.

 

Bottom line, you're looking for a unit of measure to do A, B, A on.

YMMV, IMO, etc.

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#16
Bench Racer

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i want to go  back for a moment about the point that you will get different toe readings at the track if you use a string kit in you shop measuring toe at the diameter of the rim (15 inches) or toe plates at the track 22 inches.

 

I assume the more accurate measurement is the toe plate because it takes into account the rubber beyond the diameter of the rim?

 

What number should i use??

This should start a $hit storm. We all use the 22 inch or 24 inch dimension of talking purposes for total toe, as in 1/8 toe. If I rotate my tire while on the car, my non-molested rim is much more accurate than the rubber of the tire. IMHJ, measuring at the un-molested 15 inch rim dimension and calculating the 22-24 inch tire diameter is most accurate and repeatable.  


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#17
Jamz14

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Keith,

 

Did you try a little toe in on the rear to settle the car down under braking?


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#18
Johnny D

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. IMHJ,

 

This is a acronym, what's the "J" for ??

You may have said it before but I forgot.

J~


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#19
Jim Drago

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This is a acronym, what's the "J" for ??

You may have said it before but I forgot.

J~

http://acronyms.thef...ionary.com/IMHJ


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#20
Johnny D

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Thanks Jim !!, got it, carry on. :)

J~


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