How close is too close?...back tires...

[Tallen]

Well I got a great deal on some yokohama 235/45/17's from my buddies SR20. Ok, so I went to get them mounted, fully aware that it'd be a close call. We test mounted one in the rear and found about 1-2mm of clearance. This makes me a little nervous, so I had the old tire put back on. Now what should I do? I was thinking of some THIN wheel spacers (pep boys) to give me just enough room to feel happy. What would you suggest?

 

[jtmcinder]

Run them without spacers and keep checking the knuckle for polishing.

- Jtoby

 

[Tallen]

So 1-2MM is ok? What do you guys think of slip-on wheel spacers?

 

[14.5 drift]

bad for bearings

 

[jtmcinder]

You want to be as close as possible without hitting. Maybe 2mm is enough not to rub when cornering; maybe it isn't. It's an empirical question, so go get some data. You won't hurt anything.

As to spacers: the main two problems are that they often reduce the number of employed threads on your lug nuts to the point of being dangerous (or failing tech) and they add unsprung weight (although not much). Wheel bearings are hurt by having too low an offset; whether the offset is too low because of the wheel or because of spacers is totally irrelevant.

- Jtoby

 

[Tallen]

Would a 1/4" kill bearings though?

 

[wret]

Adding an additional 2-5mm will lower your offset to the point that it will be similar to everyone else running 235 tires. What is you wheel offset anyway?

 

[Tallen]

Dunno, their Koenig Monssons from the previous owner.

 

[wret]

If they are that close with 235's I would guess you have offset in the neighborhood of +45mm.

Spacing it out a few milimeters shouldn't be a problem as long as you have plenty of thread engagement left for you lug nuts as mentioned above. I believe the rule of thumb is that minimum thread engagement must be equal to the thread diameter of the wheel stud. So at 12mm, 1.5 pitch you need 8 full turns of thread engagement.

 

[paul s]

I have about 1-2mm in the back and its been OK for the past few months you should be OK..

 

[Tallen]

Thanks guys!