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      01-10-2014, 06:36 PM   #1
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Wheel alignment: Any noticeable difference between 0.05* and 0 front toe?

I have the GC coilovers on my car and just got a wheel alignment.

Front:

Camber -1.9
Caster 7.5
Toe in 0.05* (per side)

Rear:

Camber -1.7
Toe in 0.15* (per side)


The car's a bit jumpy at the front. Feels like a bit of (unequal) wheel hops at the front. The left front seems more sensitive. I'm wondering if this is caused by the front toe-in? Would it get better if I set the front toe to 0?

And I don't know if it's placebo effect or anything, but I kinda feel weird about the front toe in when driving slightly more aggressively on freeway on/off ramps, and thought the turn-in doesn't feel very sharp. Should I be able to discern any difference between a 0.05* front toe in and 0 toe? Again, would I be better off re-setting the front toe to 0?

The rear toe in is 0.15* per side (old setting was 0.05*). After doing a bit of research, most people seem to recommend 0.1* toe in. I think my gas mileage has gone down a bit since the alignment, could it be caused by the toe in?

TIA! Much appreciated!
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      01-10-2014, 06:37 PM   #2
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And how much is a 0.05* toe-in when converted to inches?
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      01-10-2014, 06:57 PM   #3
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If anything, your car is going to want to tramline and become more sensitive with toe at 0 up front.

For me, I have 0 toe up front and the car usually wants to drift right, as the crown of the road is sloped that way. Any rut though and the tires will quickly follow that direction.

Toe-in will reduce feel on your front tires and induce understeer quicker than 0 toe.

As for the rear, toe-in essentially fights forward motion, so it isn't crazy to think that MPG has gone down as a result. I haven't experienced the same though when I went from 1/8" total to 1/4" total toe in on the rear tires.
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      01-10-2014, 07:08 PM   #4
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Thans for the quick reply. Well, I actually don't feel that much wandering right now. It's more of a up and down wheel hop at the front and I don't know if they could be caused by the toe-in.
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      01-10-2014, 07:44 PM   #5
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Quote:
Originally Posted by GP20 View Post
Thans for the quick reply. Well, I actually don't feel that much wandering right now. It's more of a up and down wheel hop at the front and I don't know if they could be caused by the toe-in.
Do you have rebound and/or compression adjustments on the shocks?

It compression, which adjusts the unsprung weight on your car....aka the wheels. If your compression is set too high when it hits a bump it can cause wheel hop.
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      01-11-2014, 11:47 AM   #6
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What you described wouldn't be caused by toe settings.

I have mine set to 1/16" total toe-out and on highways you'll have to pay attention ALL THE TIME because the car will follow whatever rut the tires get stuck in. And the steering wheel will be permanently cocked to the side the road crowns on.

But man oh man...it responds to my steering inputs so quick it's ridiculous.
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      01-12-2014, 04:13 PM   #7
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Thanks again for the replies, Kgolf31 & The HACK.

I ended up getting the wheels rebalanced and Discount Tire said the front 2 wheels were slightly off-balance. Now, I'd say that the wheel hops that I felt are 30%~40% less than before, but not gone. Maybe the rest of the wheel hops is just from the dampers and springs (440lbs front springs). I have SA dampers so I can't change the compression; rebound is at 1/4 turn from full soft so I'm not sure if I should go softer.

I'll just keep the current wheel alignment until next spring/summer and see if I get used to it.
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      01-13-2014, 06:34 AM   #8
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To answer your original question-----yes. Even 1/32nd is noticeable.

I prefer the Hack's set-up for my cars, but it is probably not for everyone. Your toe-in on the front will create will create under steer at initial turn-in.
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      01-15-2014, 04:38 AM   #9
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Quote:
Originally Posted by GP20 View Post

Front:

Camber -1.9
Caster 7.5
Toe in 0.05* (per side)


The car's a bit jumpy at the front. Feels like a bit of (unequal) wheel hops at the front. The left front seems more sensitive. I'm wondering if this is caused by the front toe-in? Would it get better if I set the front toe to 0?
Apparently too much negative camber can cause the problem you describe. When one front wheel lifts, camber thrust from the other wheel with greatest traction can shove the car to the opposite side in the instant before the load becomes equal again on both sides. You're running more -ve camber than OEM.
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