New Wheels, Need help with offsets
#1
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New Wheels, Need help with offsets
Hi all,
So i am finally thinking of going with a custom wheel(bozeforged, welds, maybe Forgelines) and i need some help.
Currently i am running C6 vette Replicas that are 18s and 19s with a 2" spacer up front and a 2.5" out back. I measured the rear wheel and got 11.5 width which seems very wide but possible and the front is 9.5.
Right now i am on a 245/45/18 up front and a 285/35/19 out back. Stock rear end width. The car is lowered 2" and will soon be on weight jack so i can adjust as i want.
Right now i am a fingers width away from the inner fendor well(no bump stops) and a good bit away from the outer(which i plan to have rolled).
I want to be able to run 305s at least on the rear without mini tubs if possible. I have the special LCAs as well out back to give clearance for wheels. I also am planning to run CTSV Front brakes with 6 piston calipers if that matters.
The new wheels will be all 18s.
So i guess what i am asking is what offsets can i run with 18" wheels that will give me the sizes i want without having to run spacers and rubbing.
My plan was to buy a set of 18s for "show wheels" keep the vette wheels as bum around wheels, and maybe get a set of rear 15s or 16s to put some drag radials on.
So i am finally thinking of going with a custom wheel(bozeforged, welds, maybe Forgelines) and i need some help.
Currently i am running C6 vette Replicas that are 18s and 19s with a 2" spacer up front and a 2.5" out back. I measured the rear wheel and got 11.5 width which seems very wide but possible and the front is 9.5.
Right now i am on a 245/45/18 up front and a 285/35/19 out back. Stock rear end width. The car is lowered 2" and will soon be on weight jack so i can adjust as i want.
Right now i am a fingers width away from the inner fendor well(no bump stops) and a good bit away from the outer(which i plan to have rolled).
I want to be able to run 305s at least on the rear without mini tubs if possible. I have the special LCAs as well out back to give clearance for wheels. I also am planning to run CTSV Front brakes with 6 piston calipers if that matters.
The new wheels will be all 18s.
So i guess what i am asking is what offsets can i run with 18" wheels that will give me the sizes i want without having to run spacers and rubbing.
My plan was to buy a set of 18s for "show wheels" keep the vette wheels as bum around wheels, and maybe get a set of rear 15s or 16s to put some drag radials on.
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Re: New Wheels, Need help with offsets
You're making this harder than it needs to be. Measure what you have, figure out how much you want things to change, and then do the math so things end up where you want. It's just that easy.....
#3
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Re: New Wheels, Need help with offsets
what quicktrip said. I'll add in if you look around you might find tire specs that are something like x wide on y width rim, as a rule of tumb, every 1/2" you change the rim width changes the tire width about .2"
FWIW, I have 305/30-18's on 18x10.5's on the back and they're a pretty good fit (outer edge lined up with the lip, not sticking out, no rubbing on the inside, if I was going to do anything to them it would be tuck them in about another 1/4" and if that caused it to rub on the inside I'd do some hammering) with a 56mm offset and a 2" spacer (so about 6mm offset in). Most people are pretty happy with 3rd gen width rears and 0 total offset on the rear, with really wide tires that puts some of the sidewall outside the lip and I would tend to try to tuck them about 1/2" more.
FWIW, I have 305/30-18's on 18x10.5's on the back and they're a pretty good fit (outer edge lined up with the lip, not sticking out, no rubbing on the inside, if I was going to do anything to them it would be tuck them in about another 1/4" and if that caused it to rub on the inside I'd do some hammering) with a 56mm offset and a 2" spacer (so about 6mm offset in). Most people are pretty happy with 3rd gen width rears and 0 total offset on the rear, with really wide tires that puts some of the sidewall outside the lip and I would tend to try to tuck them about 1/2" more.
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Re: New Wheels, Need help with offsets
Also keep in mind that wheels are measure from between the bead seats, so the nominal size of the wheel I usually around1" less then the the overall measured width. If your rear wheels measure 11.5" wide, they are actually 10.5" wheels.