Okay, this is a first for me so here goes. I'm currently modifying my 1985 Rx 7, GSL-SE from the ground up. Big juice (13B, Turbo, BIG Street Port, Slotted Rotors, Micro Tech, upgrade Clutch/Flywheel, etc....all in all I'm looking at 350hp.



I have no understanding of the offset measurements, albeit "pos" or neg" and it has been explained to me a million times over! I'm in the midst of purchasing 3 piece rims, but I am in search of the precise offset.



My 3 piece wheel is "retro" the Work Equip 03, and the size I'm going with is 15 x 7" in the front, and 15 x 8" in the rear. To see these rims go to www.worksuperwheels.com, scroll to Work Equip 03, and you'll see them (mine is the Black cut clear). These rims have a lip ranging fom 2.7" - 3.5" depending on the offset. However, prior to ordering it I need the offset and believe it or not I'm having great difficulty in getting the correct offset specs.



Can anyone help me with the appropriate offset? Any assistance will be genuinely appreciated.



Sincerely,



Yardi

 

the offset for the gsl se is 4x114.3 bro, other 1st gen models are 4x110

 

Offset, not bolt spacing.



Most people measure backspacing instead of offset. They're the same thing, but measured different ways. Offset refers to the wheel's center section being 'offset' from the center of the shell. It can be either positive or negative. Backspacing is simply the measurement from the mounting surface to the level of the inner wheel lip. The maximum recommended backspacing on a first gen is 4", which on a 15x7 rim should be about 1/2" offset. Double check with your wheel supplier to make sure.



Also, slotted rotors are pretty much just a show item on first gens. The stock brakes are more than adequate with a good set of pads.

 

Thanks for the feedback "Beater RX 7." For the 15 x 7" rim - the 1/2" you are referring to is that neg or pos? And, if my rear rim will be 15 x 8" does this mean that the offset should be 1" (neg or pos)?

 

http://www.rsracing.com/tech-wheel.html



According to my calculations it should be 1/2" positive offset (and I thought an 8" wheel would have 1" positive offset), but according to the chart on the above website, 4" backspacing on a 7" wheel is 0mm offset (-12mm for the 8"). As I said above, ask your wheel dealer.