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View Full Version : Wheel Offset.......confused



Spirit
14-07-2006, 08:01 AM
OK, can't get my head in gear this morning.

My current wheels are 7" wide with an offset of +45, and need a spacer to fit over the Kads.

I have seen some 8" wide wheels which say there are standard offset for an Evo V to IV. Now assuming this is +38, this calculator http://www.1010tires.com/WheelOffsetCalculator.asp says that this would give me 6mm less inner clearance......i.e they ain't gonna fit over the Kads, even though they are for an Evo ???

Please help someone......./help

bradc
14-07-2006, 08:11 AM
That measurement for inner clearance is the actual measurement right on the inside edge of the wheel, ie how close the innermost part of the rim will be to the suspension.

If you go from a 7" wheel to an 8" wheel with the same offset, the clearance will be 12.7mm less on each side. The standard offset for the evo wheels is 38mm.

Do you know if normal evo wheels will fit over the kads? Or do you know if the kad's protrude less than the brembo's?

Spirit
14-07-2006, 08:28 AM
So the offset alone won't prove if they will fit over my Kad's - bugger.

bradc
14-07-2006, 08:46 AM
Not at all. Uc's 18x8's have a 35mm offset, yet they only cleared his brembo's by about 0.5mm. My evo 7 wheels have a 38mm offset, yet they clear the brembo's by about 5mm.

You have to take into account the design of the actual rim, ie deep dish rims will reduce the clearance between the brake caliper and the inside part of the spoke, so you will have a reduced chance of those fitting over the caliper.

What sort of mags are you actually looking at?

Spirit
14-07-2006, 08:56 AM
These are the wheels, but in a different limited edition colour. My other concern is that as the car is also lowered, will the extra width mean I get rubbing and can I still put 225/45's on it ?

bradc
14-07-2006, 09:02 AM
hmm those spokes look fairly thick, I think it would be 50/50 if they fit over the brakes or not. Your car is very low, and I would expect you would have rubbing problems with 17x8 38mm wheels.

Spirit
14-07-2006, 09:06 AM
Well they should fit over the brakes - here they are on an Evo - but not sure about the rubbing

bradc
14-07-2006, 09:11 AM
Thats on the back of an evo though, what offset do the guys have running 4 pot brembo's on the front?

Spirit
14-07-2006, 09:14 AM
Just added a pic showing the front too

bradc
14-07-2006, 09:24 AM
ahh yep cool. I was going to say that it was an evo 4 (no arches) as well so it wouldn't have the brembo's at the front, but the guy has obviously upgraded his car. Do you know how much they clear the brembo's at the front and what offset that guy had on his mags?

Spirit
14-07-2006, 09:27 AM
Trying to get that info off him at the moment.

I can see this being a real pain in the a**, and may end up having to go to a local company to try some wheels on I guess.

Nick Mann
14-07-2006, 09:34 AM
I'd say that the fact they are on an evo 4 with brembos means they have a very good chance of fitting on a VR4 with kads. Are you sure that his are 8" wide?

Kenneth
15-07-2006, 05:55 AM
Offset = Distance from centre line of wheel to hub mounting face.

Brake clearance = distance from hub mounting face to where wheel spokes begin.

So, the bigger your brakes, the more brake clearance you need.
This is why the evo wheels have the spokes at the outer edge of the rim, to increase brake clearance.

If you reduce the offset, then you get more possible room for brake clearance. Because our cars are not made to run on a low offset, this would cause the outer rim to stand out from the wheel arch more for any rim width.

So for deep dish, you need a low offset. You then need to have an even lower offset if you need brake clearance.

Spacers reduce offset and increase brake clearance at the same time

Spirit
15-07-2006, 07:58 AM
Thanks for the replies peeps - have moved on a bit now.

Managed to borrow one of Kev's Enkei's last night to try. They are 17 x 8" with 235/45/17 tyres.

Outcome: loads of clearance over the brakes.......but nothing under the wheelarch.....could not even get a fingernail in there.....so that's out. Using the calculator I guess it's because of the extra 20mm this wheel size gives over my current wheel on the outer edge.

Got my head a bit more around this now. Looks like I am gonna need to keep to a 7" wide wheel (maybe 7.5") with an offset of +38 or less and the right spoke design. Have seen another set I like that fit this bill so gonna go to local wheel place and get them to check it all out and take it from there.

bradc
15-07-2006, 10:01 PM
It is possible to get 8" wide mags under there, you just need to get your guards rolled at the back, and you'll be perfectly fine :)