Quote:
Originally Posted by TheLetterJ
Something to keep in mind is your scrub radius. As you turn, your tires will swing in an arc front to back (pivoting around the balljoint.) Even if it clears the fender opening while pointed dead ahead, it will still require a larger opening front to back to allow for the swing of the steering.
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I did some more PCAD to visualize what starts to hit when turning the wheels. I labeled this as Tire sweep rather than scrub radius.
I measured the distance from the balljoint's center to the rim's inside edge for my 17"x8" -12mm wheels; it was about 1" even though the side wall bulges out closer to the balljoint turn center.
I show three tire profiles for -25,0,+25 degrees from the top down. The rectangle is the tire height x tread width ignoring bulging side walls. I just picked 25 degrees; I did not actually measure it.
To keep everything straight I showed a nominal required wheel well as well as some dimension of required internal space.
Trying to deal with the variations in wheel size and offset was a little beyond the accuracy of this simple analysis so I just kept the inside wall of the tire at the same spot for all the variations.
The little ball in the center represents a turning radius of the inner rim with the previously mentioned 1 " offset from the ball joint center.
So it is clear that the main issue with tire clearance is going to be on the inside rear of the wheel well when turning the fount of the tire out.
The first thing to cut back is the outside portion of the wheel well (requires corresponding pie cuts from the fender as well) as I show in the pictures and then make sure the suspension is lifted enough to keep the floor well above the tire with a compressed suspension. Otherwise, you will rub on where the floor meets the air vent humps.
Quote:
Originally Posted by TheLetterJ
The narrowest part of the lower/backside of my front fenders is now no more than 1" and the cut extends roughly 10.5-11" upwards from there.
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Did you have to go any further than the picture that I showed which cuts off the pinch weld and cuts out a pie section from the inner/outer side walls (shown as 1 1/4" in front of the door?
The next level is to actually cut a pie section out of the floor where the inner wheel well meets the floor in the front seat foot area. This requires pulling back the carpet and any wires running at the base of the wall.
This area is probably the driving limitation for putting lift into the front end. You need lift to get the floor above a significant portion of the tire and still allow for spring compression.
Quote:
Originally Posted by TheLetterJ
I also had to bend the outer corners of the lower seam of the core support/inner fender forward as my tires had left a polished spot right there.
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Is this in the front or the rear?