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-   -   what is the lowest offset wheel possible on GSL-SE (https://www.rx7club.com/1st-generation-specific-1979-1985-18/what-lowest-offset-wheel-possible-gsl-se-845150/)

RotaryRevn 11-03-10 12:57 AM

5 Attachment(s)
More pics 16x8 +26.

In the last pic, I ran a straight edge up along the outside of the wheel so that you can see how far past the fender the outer part of the wheel goes.

https://www.rx7club.com/attachment.p...2&d=1288763729

https://www.rx7club.com/attachment.p...3&d=1288763729

https://www.rx7club.com/attachment.p...4&d=1288763729

https://www.rx7club.com/attachment.p...5&d=1288763729

https://www.rx7club.com/attachment.p...6&d=1288763729

jshiz 11-03-10 01:00 AM

Nice. Can't wait til you add tires.

RotaryRevn 11-03-10 01:23 AM

5 Attachment(s)
Now keep in mind, the front is another animal. Since I have a staggered set of these wheels 15x8 +26 and 15x7 +25, I was able to finally figure out the offset on my fins.

The fins on my car have about /if not the exact same backspace and lip as my 15x7 +25 mesh. So in my mind, the fins are 15x7 +25 all around.

IMO, 15x7 +25 is about the lowest offset you can go in the front without going past the fenders. I have quite abit of negative camber up front right now so it appears like there is room for a lower offset, but I think if I didn't have all that negative camber, they would sit about flush in the front. One day I will know for sure because I'm not keeping that negative camber, it's only there because my car hasn't been aligned yet.....lol

Anyways, you can use the 16x8 +26 as an example (If your gonna roll your fenders) and adjust the offset for a 7 inch wheel if you wanted the outer edge of the wheel to sit about the same with the fender as my example.

Just for kicks, I threw the 16x7 +25 on the back so you can compare how close it sits to the fender.

With 7 inchers in the back, you should use a lower offset IMO if your going for the flush look.

https://www.rx7club.com/attachment.p...8&d=1288765405

https://www.rx7club.com/attachment.p...9&d=1288765405

https://www.rx7club.com/attachment.p...0&d=1288765405

https://www.rx7club.com/attachment.p...1&d=1288765405

https://www.rx7club.com/attachment.p...2&d=1288765405



I'm hesitant to say this but my measurements on the inside with the 8 inchers tell me that I "might" be able to squeeze a 9 incher back there if I use a higher offset to pull the wheel in more and compensate for the extra inch. I have about 1.25 inch space on the inside before hitting the closest thing which is the ebrake cable. I'll have to take better measurements on that when I have time (which will be awhile).

RotaryRevn 11-03-10 01:47 AM


Originally Posted by jshiz (Post 10300673)
Nice. Can't wait til you add tires.

Thanks man, I'm afraid it might be awhile before I get the tires as time is short right now.......maybe by Sevenstock 14......lol

RX-7 Chris 11-03-10 09:47 AM

What brand wheels are those?

I wanted to go with 15x7s on my SE, so I should look at a 20-25mm offset?

jshiz 11-04-10 11:45 AM

If you want flush, I'd imagine you'll want 10-20 offset in the back with 7 inch wheels. (Based of the photos

RotaryRevn 11-04-10 12:27 PM

1 Attachment(s)

Originally Posted by RX-7 Chris (Post 10301078)
What brand wheels are those?

I wanted to go with 15x7s on my SE, so I should look at a 20-25mm offset?

They are SSR Reverse Mesh. They are kinda hard to find here but they seem to be available everywhere in Japan for fair prices. I actually just picked up an identical set to these, the exact same size and offsets (only with black centers). The transaction is getting finalized but they should be here in about 2 weeks. I sure don't need them but from what I have seen, 16's are abit more rare in these wheels so I grabbed them.

As far as sizing, I would say in the back of your car, 7 inchers a +13 would get you flush according to this handy offset calculator........

http://www.imadeskidmarks.com/offsetcalculator.html

I just put in the size of my rear wheel 8" +26 as the starting wheel, then threw a 7" wheel for the second wheel and experimented.

One thing you have to remember though is that with a 7" wheel, it will be harder to stretch a tire of decent size because the wheel is smaller. I would think the largest tire you could go in back would be 195 but even with that, you would be cutting it close to rubbing depending on how low your car is/ how stiff your springs are etc.

You can see with my pics, the rear wheel edge sticks just past the fender, so the tire would probably be right under the fender edge if it wasn't stretched. For this reason, you might want to go with just a tad higher offset than a +13?





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In the front for the flush look, I'm not yet sure of the close to perfect offset but for now, I'm not recommending more than a +25 on a 7" wheel. My fronts have a lot of negative camber so although the top doesn't look flush, the bottom of the wheel appears like it might be if I take out the unnecessary negative camber. I'll play with it when I get more time.


I've attached a picture to help some with the backspace vs offset confusion. This pic was taken from skidmarks website.....he's got some cool stuff on there

https://www.rx7club.com/attachment.p...0&d=1288891555

RotaryRevn 11-04-10 01:07 PM

Use an inch to mm conversion to figure out offset's

http://mdmetric.com/tech/cvtcht.htm

1" = 25.4mm

Here is an example on how to play with offset. When I did a quick measurement under the rear of my car with my 8" +26 wheels, I had about an inch and a quarter space on the inside of the wheel to the nearest rubbing point (super quick measurement only). When going from a 8" to a 9" wheel and keeping the same offset, it will add a half inch to the inside, and half inch to the outside of the wheel. So if I wanted to go from my 8" +26 wheel to a 9" wheel and have the outer lip stay at the same location relative to the fender, I would have to move that extra half of an inch on the outside, toward the center of the car. So I would want to increase my offset by .5" or 12.7mm. I would take my current offset of +26mm and add it to +12.7mm = a new offset of +38.7MM on a nine inch wheel. This should move the wheel in half of an inch, added to the other extra half an inch on the inside (due to the 9" wheel) would bring my wheel a total of 1" closer to rubbing the inside of the car. This would leave me only about 1/4 inch space before rubbing. Of course wheel makers don't make fractions of a mm when doing offsets so you would have to round one way or another.

By searching, I found that SSR currently makes some 9" wheels with a +39 offset . So now, I am trying to find some SSR Reverse mesh (or similar SSR barelled wheel) in 16x9 +39................LMAO I don't even know if they made this style of wheel in that size/offset but I'm on the hunt..........I want to see if I can actually fit a 9" wheel under a stock bodied first gen with SE suspension. I really need to spend some more time under my car... even if I get 9"ers on there, I need to make sure that there won't be tire rub issues on the upper/inner wheel well. I forgot to look at that. Either way, these 8"ers will get tires on them, then I'll see where I'm at.


*******DISCLAIMER*********
Please don't take my info as gospel, you should always do your own test fitting and measurements, that's the only way to really know as taking something from paper "should work" and actually trying it is still 2 different things. I hope the numbers I provided are accurate as it is easy for me to get off track.......especially without coffee.......lol I am in no way an expert on this (I could be mistaken), you can see the date I started this thread and at that time, I new absolutely NOTHING about offset's or backspace so I am just doing alot of searching, googling ect. And this is what I think I have learned.
*******DISCAIMER*********

MacLoGoS 01-24-12 03:30 PM

Hey so i dont mean to just pop in and ask questions but i also havea GSL-SE with stock fenders and wanted to know if i could fit a 16x8 with a 38mm offset on the front and back without rubbing? I know the stock offset is 40 so i think 38 should have it sit flush if i get the right sized tires. But i just wanted to know if i should get 16x7 with a 40mm offset or the 16x8 with a 38mm offset. Thanks. Oh and i do have lowering springs with coilovers and a camber adjuster.

thorage327 01-27-12 12:03 AM

2 Attachment(s)
I just bought a SE with 16x7 40mm offset. The front is just a bit under flush, but has to have 1/4 inch spacers to keep off of the Coil Overs. Rear is fine. Running 205/40/16's.

I am going to change these out for 15x8 with 20mm offset when the turbo install if finished.

Bern 01-27-12 01:57 AM

Gino (Team_Gileto) is running a sick set-up on his SE, 16x9 on the rear... but it's not exactly a bolt-up.... :icon_tup:


The specs are 16x9+15 with 195/50/16 tires. i am now switching to 195/45/16 on the same wheels. no spacers. they poked about 3/4" in the rear, but they sat fine up front with camber. i'm now taking care of the rear problem by metal flaring the back about an inch.

definitely not an easy set to pull off and if it wasn't sitting as low as it is then it would look weird

http://farm7.static.flickr.com/6145/...e6583047_b.jpg


-Bern


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