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Before I start I know this question has been brought up 100000000042069 times. I have searched and read but the information seams to get mixed up between the 12a gsl and 13b gslse, now I am confused on what will fit and what wont.
I have a 1981 gsl, I want to run 15x7 rpf1s with 1 inch wheel adapters . What offset do I need to fit in the stock fenders with stock suspension? They have 15x7 with 35 and 41 offsets, I would also settle for 14x7 in 19 or 28 if that would work with a 1in inch 4x110 to 4x100 adapter. Would consider the 16 as well
Most people get 15 x 7 with 20mm offset, 4x110 and 195 or 205 width tires (205/50 r15). Those RFP1's are nice wheels but I don't know what specs you'll need to fit them with a bolt circle adapter / spacer. There are other style Enkeis though that do come in 4x 110. Rota makes several styles too (I like their Shakotans) or Panasports.
Most people get 15 x 7 with 20mm offset, 4x110 and 195 or 205 with tires (205/50 r15). Those RFP1's are nice wheels but I don't know what specs you'll need to fit them with a bolt circle adapter. There are other style Enkeis though that do come in 4x 110. Rota makes several styles too (I like their Shakotans) or Panasports.
I will look at the Rotas, I'm wanting something that isn't a mesh or a Panasport wheel. Nothing against them just want something different.
Before I start I know this question has been brought up 100000000042069 times. I have searched and read but the information seams to get mixed up between the 12a gsl and 13b gslse, now I am confused on what will fit and what wont.
I have a 1981 gsl, I want to run 15x7 rpf1s with 1 inch wheel adapters . What offset do I need to fit in the stock fenders with stock suspension? They have 15x7 with 35 and 41 offsets, I would also settle for 14x7 in 19 or 28 if that would work with a 1in inch 4x110 to 4x100 adapter. Would consider the 16 as well
With a 1 inch adapter (25.4mm) 15x7 with 41 offset I should have 15.6mm offset to the hub. Will that fit or am I thinking wrong?
So the 15x7 Konig Rewinds have a 20 offset and they fit just right. So just do the math to get your spacer thickness. Personally wouldn't use a spacer but I've seen it done before.
So the 15x7 Konig Rewinds have a 20 offset and they fit just right. So just do the math to get your spacer thickness. Personally wouldn't use a spacer but I've seen it done before.
not the biggest fan but its better than using wobble bolts on 4x108 wheels. Big trucks use them all the time my shitbox should be safe with them.
The advantage offered by 4x100mm wheel is greater variety and they are lighter than 4x110mm and 4x114.3mm wheels. So i converted my RX7 using a 25mm adapter spacer on the front and by having my GSL axles drilled to 4x100mm. This is on a race car and I run 15x8" with a 35mm offset Kosei wheels for dry tracks. My rain wheels are 15X7 with 25mm offset. I have rolled fenders and my car is about 3.5 inches lower than stock.
What I found when I did this is that the rear axle is wider than the front when I measured from hub face to hub face at ride height. So I really only needed spacers on the front. I ended up running the 25mm adapter + 10mm spacer so that the front wheels have a 0 offset. On the back I use a 5mm spacer to keep the tires from rubbing on the suspension on the driver's side which means the rear has an effective offset of 30mm. Allot of this is because of the way Hoosier racing tires are made. With 205/50 15 street tires you might not need that much spacer on the front.
I don't really like running spacers either because they add weight and it is one more thing to check and keep tight. But they work and are safe as long as you make them hub centric because that takes the side load off of the studs. I had the ones I have made by a machinist I trust because that way I knew the material being used and that the studs are from ARP.
The advantage offered by 4x100mm wheel is greater variety and they are lighter than 4x110mm and 4x114.3mm wheels. So i converted my RX7 using a 25mm adapter spacer on the front and by having my GSL axles drilled to 4x100mm. This is on a race car and I run 15x8" with a 35mm offset Kosei wheels for dry tracks. My rain wheels are 15X7 with 25mm offset. I have rolled fenders and my car is about 3.5 inches lower than stock.
What I found when I did this is that the rear axle is wider than the front when I measured from hub face to hub face at ride height. So I really only needed spacers on the front. I ended up running the 25mm adapter + 10mm spacer so that the front wheels have a 0 offset. On the back I use a 5mm spacer to keep the tires from rubbing on the suspension on the driver's side which means the rear has an effective offset of 30mm. Allot of this is because of the way Hoosier racing tires are made. With 205/50 15 street tires you might not need that much spacer on the front.
I don't really like running spacers either because they add weight and it is one more thing to check and keep tight. But they work and are safe as long as you make them hub centric because that takes the side load off of the studs. I had the ones I have made by a machinist I trust because that way I knew the material being used and that the studs are from ARP.
This is the info we need. I do like the thoughts of having 8s in the back. I can make that happen. Thank you for the info.
Like Scott, I use 25mm spacers on my racecar. I have had one failure. That occurred when I somehow managed to only install 3 of the lugnuts holding the spacer to the front hub. Otherwise no issues at all.
With Hankook Rs4's, 225-45-15 and Toyo RR, 205-50-15 I can use ET30 to ET40 (Team Dynamics ET30 and ET40 and Kosei ET38). With 205-50-15 Hoosiers, the ET40 tires rub slightly on the 2.5" coilovers. ET30 pushes the tires out to the edge in front with flattened (take of the front fender and flatten the lip with a rubber mallet) lips. A bit more room in the rear. No rubbing either end though.
I like the adaptitusa adapters, because they attach with "shouldered" lugnuts, that seem to support the spacers more positively than cone type lugnuts.
Like Scott, I use 25mm spacers on my racecar. I have had one failure. That occurred when I somehow managed to only install 3 of the lugnuts holding the spacer to the front hub. Otherwise no issues at all.
With Hankook Rs4's, 225-45-15 and Toyo RR, 205-50-15 I can use ET30 to ET40 (Team Dynamics ET30 and ET40 and Kosei ET38). With 205-50-15 Hoosiers, the ET40 tires rub slightly on the 2.5" coilovers. ET30 pushes the tires out to the edge in front with flattened (take of the front fender and flatten the lip with a rubber mallet) lips. A bit more room in the rear. No rubbing either end though.
I like the adaptitusa adapters, because they attach with "shouldered" lugnuts, that seem to support the spacers more positively than cone type lugnuts.
Good luck.
Carl
Wow thanks for the info. Its amazing how friendly everyone is with wheel questions, god forbid you have a boost or engine management question though. Thanks to all the good info everyone. Hopefully this helps other people too.
I would add that one of my goals was to be able to rotate tires/wheels front to back because the gets the most life out of a set of tires during a season. My other goal was to take advantage of wheels made for a more popular car - the Miata. I mean spend some time on www.good-win-racing.com or www.tirerack.com and see what is out there with respect to Miata wheels. The math worked out that a +35mm offset 15x8 wheel is the easiest for me to work with but I could probably make a +28 or +25 wheel work.
To save weight on the front I have considered ditching the spacers and using 0 offset 4x114.3 wheels but it would mean that I have dedicated front and rear tire/wheel packages. I could still rotate front to back but it would mean visiting the tire guy at the track more often.
Here is a shot of the car. I was running 225/45x15 Hoosiers on the rear and 205/50x15 Hoosier SM7s on the front.
That looks awesome Manny! Someone in another thread was wondering what Enkei RPF1's would look like on a 1st gen. With a similar design, your rims look awesome. I especially like the two-tone w/Gold.
03-06-21, 05:03 PM
