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-   -   End all for wheel fitment on Respeed brake kit. (https://www.rx7club.com/1st-generation-specific-1979-1985-18/end-all-wheel-fitment-respeed-brake-kit-588603/)

85rotarypower 10-18-06 01:26 PM

End all for wheel fitment on Respeed brake kit.
 
5 Attachment(s)
Alright, I've wanted to get the respeed big brake kit for my 7 for quite a while now. I've been doing tons of searching for the answers on the forums, never really could find a straight answer on fitting of a 7" wide wheel, and a lot of people asking the same questions over and over with no clear answer. But, I've got the answer for you. About a +13mm offset is the required offset when using a 205 tire, pretty much the widest you can fit on the front of a 7. I don't believe you would need to roll the fender with this offset, but I could be wrong. Wheel width has no bearing on this number as the overall width is the same + or - 1/4" with a 205 tire.

I used my stock + style wheel with a 205/60R13 tire to do all the measurments. This wheel has a +25mm offset. The 205/60 has a total width of about 8 1/4", which is right in line with most 205 tires. Now, using this as a base on the stock spindle, I determined that the tire just barely touches the spring. This of course would not do, so a spacer needed to be made to determine a proper offset. Since this spacer would not be used on the road, just for display purposes, so I made it out of 1/2" thick MDF wood. This wood if fairly accurate for this purpose. But anyway, I found a 1/2" spacer would work great and give me the proper amount of space between the spring and tire. IMO, no less than a finger width is required, and thats what I got. This spacer gave an effective offset of +13mm on the stock rim. So, I hope this all makes sence. The main fact here is that the wheel width has NOTHING to do with the fitting of the wheel. Only the overall width with the tire and the offset of the wheel.

Here are a few pictures of the stock wheel with a 1/2" spacer.

https://www.rx7club.com/attachment.p...d=202003&stc=1

https://www.rx7club.com/attachment.p...d=202004&stc=1

https://www.rx7club.com/attachment.p...d=202005&stc=1

https://www.rx7club.com/attachment.p...d=202006&stc=1

https://www.rx7club.com/attachment.p...d=202007&stc=1

t_g_farrell 10-18-06 03:02 PM

Thats interesting because I've run 205/60R13 for years on my stock waffle wheels on my SA and never had them rub the springs. Maybe the plus wheels and/or the FB is that much different than an SA.

DOH! I just reread the title, this is with the ReSpeed kit installed, right? I don't have that.

dbragg 10-18-06 03:57 PM

i have 205/40/16 on my car with the respeed kit. i havent driven the car yet, but i dont think theyll scrub, but i may have to roll the fender

vipernicus42 10-18-06 04:23 PM

I have Sumitomo 205/60/13s on my 7 right now and get absolutely 0 spring rubbing....

RB Springs, KYB GR-2 Shocks, stock 13" + rims

Jon

Rico Suave 10-18-06 10:23 PM

3 Attachment(s)
OK, i have 215/35/18 tires on 18x7.5 wheels with NO rubbing issues. Now i upgrade the springs to a Ground Control coil over set up to fit the wheels.

85rotarypower 10-18-06 11:39 PM

It doesn't matter if the respeed kit is installed or not. The mounting surface is still in the same basic position.

All I'm trying to say here is that the specs I posted above are probably the safest you could go with. You could probably get away with a +20mm offset without any problems, but I feel safer with more space between the strut and the tire. Using this, a 215 tire probably would fit, but the clearances are too close for me to like too well.

vipernicus42, its strange to me too. I bought these for the back of my car originally, but tried them on the front for shits and giggles. Drove around on them without a problem. That was 2 years ago. The only thing I changed was the strut assembly to one from an 84 GSL, giving me the larger bearings I need for the respeed kit. Really is a strange phenomenon. I can't figure it out.

85rotarypower 10-31-06 01:59 PM

I guess nobody cares about this? I just wasted my time figuring everything out?

82transam 10-31-06 02:21 PM

no you didn't, it confirms what I had calculated earlier when I had some free time, seems somewhere between .9-1" will be just about right.

t_g_farrell 10-31-06 02:24 PM

Not a waste of time. So now you've given more info. Looks like the 84 strut assembly in a 82 chassis causes the rubbing. I have a stock 80 SA with stock struts and RB springs with 205/60x13 tires and have no rubbing at all in the front or rear. So I have to think it's the different struts. Is the lower control arm different for an 84/85 and the rest of the 1st gens? Somethings different here causes this.

85rotarypower 10-31-06 02:38 PM

I'm starting to think that there was a different offset for 84 and 85 from 79-83. Anyone have a 79-83 strut with hub installed that they could measure? I specifically remember that the clearances were close on the stock 82 struts with those 205 tires but not too close to create any problems, but there is a definate rubbing now with the 84 struts.

20bdreams 10-31-06 05:27 PM

ok i see that most people are running these tiny13-15'' wheels with snow tires (50-60) side wall....im trying to go for a more modern look. i would like to fit a 16-17'' with a low profile 35-40 side wall and would like to have a nice lip so i can make it look like it really is a rear wheel drive car. i have an s4 gsl-se, but im thinking about going with the respeed kit...how can i make what im trying to do work using fenderflares.

dbragg 10-31-06 05:34 PM

1 Attachment(s)
i have 16x7 and 16x8 Work equips. im running 20/40/16. i need bigger tires for the rear. here is a pic to show you how my car looks now. my rear wheels currently stick out past the fender lip, but after i get my rear axles redrilled they should come out right to the fender.

rotor vs. piston 10-31-06 05:53 PM

Your car is looking good '140... I run 225-50-16's in the rear on 32mm offset and only have a slight rub... just need to roll the fender a little.

The main problem I've found on the front of the 7 is the tire rubbing the swaybar... I have a ST bar but it's not *that* much bigger than stock. This was when I ran my 205-45-16's on 42mm OS rims... now with the 32mm the same tires don't rub at all.

82transam 10-31-06 06:22 PM

I've never had my 205's rub the spring, but at full steering lock they rub the sway bar as rotor vs piston says. I have the pst 1 1/8" bar. I'm not sure what difference the 84/85 spindle would make, as far as I know the only difference is the bearing surface itself, the rest should be the same. Struts are sold for 81-85 so it should all be the same...

85rotarypower 10-31-06 07:44 PM

Thats what I thought 82transam. I've been trying to figure it out myself why my 205's rub now. It makes absolutely no sense. I guess I'll have to go through mounting them back on the front again to try an figure it out.

20bdreams, you would be best off with a 17 and a 205/40R17 tire. Probably give you the look you want, and their the same overall diameter as stock so you won't have any problems with the speedo. Personally, I'm going with 16's and a 205/45R16 all around. I may go to a 225/45 in the rear, but still thinking about it.

20bdreams 11-02-06 06:00 AM

yeah a 205 tire with a 17'' rim is all good but still pretty skinny. im going to be using fender flares from selectmaz.com.au and am looking for a nice (WIDE) rim. not necessarily a larger rim. if i can get away with a wide 17'' then yeah but im leaning more towards a 16''. i want my rims to stick out quite a bit to give it that super agressive stance.

woodonastick 11-02-06 12:22 PM

good job trying to figure this out. there was a well..nto really heated debate abot this before too. i started a thread about last year about this. i ended up with a 1" spacer running a +38 offset on a 15x7. tires are 205/50/15. this set up cleared the springs a little too fine. i think if u have the kit, and dont want a spacer, i believe a good offset for that would've been a 10? anyways in the future i plan to run a 225/45/15.

wecycle 11-04-06 10:56 AM

SA wheels
 
Your work confirms the measurements that I have done.
13mm offset appears to place the wheel to allow the widest tire without rubbing or modification.
It looks like a 225/50-15 will clear without rolling the front fender lip, depending on the specific tire. (Different brands may be as much as a full "size" off from what the sidewall says.) The rear looks fine with 225's.
My measuements were based on 7 inch wide wheel. If you use 8 inch the tire bulge will be about a half inch wider.
Note that this is all "on paper".
I talked to a few wheel companys at SEMA and the general trend was they need a run of about 200 wheels (50 sets) to make it worthwhile to them to build a wheel to our specs. (15x7, 4 on 110, 13mm offset, polished lip, mesh or 10 spoke, option for different color centers, exposed lug nuts (no cap) .)
I will start a group buy thread when or if any of them come through with a deal.
By the way THANK YOU for doing the research on this. There have been so many threads asking for info on "what is the largest wheel/tire" and most get answers like "my 195's fit OK", but no thorough reseach like what you have done and most with only partial specifications.


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