http://rayswheels.co.jp/cgi-bin/cgi2...?modelName=GTS

This link takes you to the sizing chart for the GTS wheels. I have a question here.

Notice that a 10.5" +30 offset on offset A (The one defined for my car with BBK's) has a rim depth of 94mm.

On offset C (which will work for my BBK's as well) 10.5" +37 has a rim depth of 107mm.

I realize that the higher the offset the further out the face is, than am I to assume that the +37 would stick out 6mm more than the +30?

I'm pretty damn stupid as you can see so any help would be appreciated.

 

You have it backwards. The lower the offset - the closer to the fender.

 

I should have known seeing how my understanding made no sense. Thank you.

 

Okay how about another question:

What would the +30 with 3.7" lip look like compared to the +37 with 4.2" lip?

This is in the rear btw.

 

No comment on the lip but use a offset calculator to compare the wheels. Reference: http://www.1010tires.com/WheelOffsetCalculator.asp

 

why aren't you going with the normal +18 in the rear?

 

Too aggressive. I currently have that setup and 285 is as wide as I can go. I'm F/I so I need all the traction I can get. Plus I guess the rears sticking out so much are beginning to bother me.

 

I'm not sure your correct. Per Tirerack the more positive the number the further toward the front/street the mounting surface is.

http://www.tirerack.com/wheels/tech/...jsp?techid=101

Now if you take that into consideration won't the +37 with more lip stick out further than the lower offset wheel?

 

David was correct. If you don't want the +18, get the +28 "B" face.

 

Actually he is wrong and so are you. If you would look at the link to Tirerack you will see that. Now am I reading it wrong? Is Tirerack sending out bad info? I'm not sure. What I do know is you guys are saying it is backwards according to Tirerack. As far as the +28 is concerned it doesn't say that it will clear our BBK's.

 

No. For example, a 8-inch wheel is 8-inches wide regardless of the width of the lip.

 

I like this calculator more: http://www.rims-n-tires.com/rt_specs.jsp

 

I realize that, but how are they getting a deeper lip on the +37 than the +30? The higher the positive number the further the mounting to the edge of the front lip. The only plausable reason is that the spokes are more curved, correct?

 

Correct. The spokes are shaped differently. The technique used to mount the spokes to the outer wheel may also be different. Remember that the objective of offset and spoke design is to clear the brake calliper.

 

Gotcha. I completely understand now.

 

+28 has MORE clearance than the +37 because of pad type/offset and WILL clear a BBK in the rear. Straight from the chart: ･The OFFSET B in the size table denotes models matching big calipers of FAIRLADY Z (Z32), RX-7 and
IMPREZA (GDB/BREMBO calipers). A is typically a front fitment with a small lip and maximum brake clearance. B will clear BBK's in the rear and has a medium lip. C is designed for maximum lip and will have the least amount of clearance, depending on the size/offset will still clear BBKs.