My new bling 15x8 Kodiak Rims :)
09-17-09, 08:20 PM
#76
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What backspacing is necessary for 8 inch wheels to not rub on the front and/or sit flush? I'm doing some (premature) wheel scouting, and I'd like to run as wide as I can fit inside the fenders.
09-18-09, 10:16 AM
#78
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From my measurements you need to have about 15 to 20 mm offset at least on a GSL-SE. I am planning on getting XXR 501 in 15X8 which come with a 15 offset. I will put some 225 width Nitto NT01s. If they don't fit off the bat I am going to mill 5mm off to bring it to 20mm.
https://www.rx7club.com/1st-generation-rx-7-1979-1985-vehicles-109/85-gsl-se-rebuilt-turbo-ii-swap-851037/
Here is what they look like on a GSL-SE.
https://www.rx7club.com/1st-generation-rx-7-1979-1985-vehicles-109/85-gsl-se-rebuilt-turbo-ii-swap-851037/
Here is what they look like on a GSL-SE.
09-19-09, 12:49 AM
#79
even in that picture it looks like they stick out about the same as mine but just the rubber is a little skinnier than mine (perhaps a 215 width or so). If you have coilovers you can probably tuck them in a little more but its all going to come down to the springs pretty much. Like with my eibach springs right now i'm about 1/4" away from the front springs. You can easily make the rear fit inside but the stance looks better with the same offset all around.
09-19-09, 09:16 AM
#80
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Yeah thats why I am thinking of trying to mill about 5mm off the mounting surface. I am not sure if it is possible or not since I don't have the rims in front of me. I have RE-Speed coilover and the springs are a smaller diameter than stock so I should be ok.
The best thing about the these XXRs are they are cheap. You can find them for about $350 shipped. They are dual bolt pattern 4x100 and 4x114.3 and only weight 13lbs each. So if they don't fit right I can resell them at almost no loss.
The best thing about the these XXRs are they are cheap. You can find them for about $350 shipped. They are dual bolt pattern 4x100 and 4x114.3 and only weight 13lbs each. So if they don't fit right I can resell them at almost no loss.
09-22-09, 11:29 PM
#83
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Everyone has to worry about backspacing. Otherwise you end up with wheels that hit the fenders under suspension compression, or rub the springs. Both can be very dangerous. Correct backspacing is important and is a major consideration when buying wheels. You don't just buy a set of wheels that look pretty and worry about fitment later.
09-22-09, 11:55 PM
#84
So finally had a chance to roll the fender out today, just got done a few minutes ago. The inner lip on the rear is bent up pretty much 180 degree, and also the whole flare seems to have been pushed outwards also about 1/4" or so. I'm going to hopefully get a good run tomorrow or the day after to see if any rubbing still presists.
10-07-09, 01:26 AM
#86
Well I did one AutoX and one lapping/time attack day with the tires and must say they seem to work pretty good. A tip for anyone running the R888 if your tires look like they are wearing in the center more than the outside INCREASE your tire pressure! You should be running 45-47psi hot so about 40 cold. Its not like other tires.
I don't know my lap times yet but butt feeling says atleast 5 seconds off my regular time.
I don't know my lap times yet but butt feeling says atleast 5 seconds off my regular time.
10-07-09, 11:20 AM
#87
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Weird, that sounds very counterintuitive to me. If I saw my tires wearing more on the center, I would decrease my pressure. If they were wearing heavily on the edges, I would increase.
But hey, whatever works, right? You can't argue with real world results.
But hey, whatever works, right? You can't argue with real world results.
10-07-09, 01:23 PM
#88
Ya I know its a little backwards, but I read it on a NASA website prior to me going to the event. And funny thing is that there was an SRt-4 running the same tires and he kept on getting a funny wear on the center and I told him to try that out and the wear was gone.l
10-07-09, 01:52 PM
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Well I did one AutoX and one lapping/time attack day with the tires and must say they seem to work pretty good. A tip for anyone running the R888 if your tires look like they are wearing in the center more than the outside INCREASE your tire pressure! You should be running 45-47psi hot so about 40 cold. Its not like other tires.
I don't know my lap times yet but butt feeling says atleast 5 seconds off my regular time.
I don't know my lap times yet but butt feeling says atleast 5 seconds off my regular time.
seems like there might be a double humped curve with these... there is a low pressure that wears and tempratures ok, and a higher psi that does the same thing
10-08-09, 12:21 AM
#90
Here's the whole write up concerning it:
Originally Posted by Spec Miata Community
Hope Ron doesn't mind me sharing this with all of you..
Ok, here's the deal on the R-888's.
I'd advise you one and all to TRY the suggestions I will make and then make a decision as to the speed and durabilty of the R-888 Vs the Ra-1 AFTER you try these new ideas.
But only AFTER you try the new settings.
A bit of History:
I first experienced excessive wear and bad handling of the R888 at the 2007 NASA 25 hour race on Mike Quan's Honda Civic with Roger Foo at the wheel.
Great team, excellent drivers. They came down in the middle of the night to ask if I could look at a tire issue they were having. Seems that TOYO had given them some new 888's to 'try' in the 25 hour race. First off, during a race is the WRONG time to try anything NEW. Let alone sort out a new tire. But, it was what it was and these things happen.
The issue was the car was pushing (front wheel drive car) and was wearing out the centers of the tires at an alarming rate. Well, one look at the worn centers and I suggested LOWERING the pressure. We did. And they began to wear out QUICKER and the handling became worse! It made no sense to me whatsoever.
Fortunately the team had enough RA-1's to complete the race and never put the R-888's back on the car. But, that adjustment in air pressure SHOULD HAVE worked. It had for years on all types of tires. But it didn't and it stuck in my mind over the winter.
The start of the 2008 season:
In the NASA races the BMW E-30 class cars were allowed to run either the RA-1 or the R-888 until June of 2008. Most jumped to the R-888 right away.
But that deal about the tire wearing out quickly in the middle still bugged me. So, I kept an eye on them.
Early on I asked Donny Edwards to allow us to 'try' something on his E-30. At Thunderhill we sent Donny out at 40 lbs STARTING pressure! He had already raced on them with the normal RA-1 starting pressure of 32 lbs, ending at 40lbs hot and was doing well. But, now I was asking him to START at 40 lbs.
His comment after coming off the track was that the car felt more stable and quicker. His times proved that he was correct. We kept an eye on Donny's car during the year and asked if he was getting any excessive wear. Donny's comment was that the car was used not only for the E-30 practice, qualifying and races but for every available session during the weekend. And no, they didn't wear quicker.
With this knowledge I then asked a HPDE driver, another trusted friend, if he would go out at 40lbs cold in his Porsche All wheel drive 911 Turbo. The thing weights a ton! He had already been out for 2 sessions at the lower RA-1 pressure setting on his new R-888's and LOVED the tires. Now, I was asking him to go out at a starting pressure of 40lbs. "Are you crazy" he asked. Maybe, but just try it for me.
His comment in coming off of the track was "I thought they were hooked up this morning with the lower pressure, but now they're REALLY hooked up." He loves the R-888 tires.
I'm relating these stories to help you all understand that I didn't come by these very unusual pressure settings without some forethought, testing on various cars with different drives and then analyzing the results.
Last story. At the NASA banquet one of the E-30 competitors came up and said that he finally put the pressure up to where I suggested at the last race. I asked how it worked for him. He said that he had turned a lap only 1/10th of a second off of Donny Edwards fastest lap. I asked why he had not done that earlier in the year and he stated that he just couldn't believe that pressures that high would work. Even though HE had maintained Donny's car all year and knew exactly what we were using for starting pressure!
Asked how high the air pressure was that he used before, he said that he had started them at 38 and they went to about 42-44 hot. But, that the hot pressure Donny ran was 45-47. He stated that he could not believe the difference that 45-47 hot pressure made on his car. That it just came alive. 2-4 lbs in hot pressure does make a difference.
E-30's wear? Even across the tire! Heat cycle 0. Wear rate: same as or better than the RA-1. How long do they wear? Down to the cords, just as the RA-1s did.
We've used these same pressure settings for a Porsche 996 Cup full race car that normally races on Michelin or Yokohama slick tires and with the same results. No heat cycling, no excessive wear and totally fun and drivable.
SM competitors, the R-888 has a different construction. A huge change in the design of the tire. You must make some changes to:
1) Your driving style
2) Your air pressure settings
3) Your chassis setup
To get the most out the new R-888's.
Staying with the same old setup, same old pressure and same driving style will not prove beneficial.
My suggestions:
1) Start with the exact chassis setup you have with the RA-1
2) Start the R-888 with 40 to 42 lbs of pressure.
3) Look for 45-47 as your hot pressure goal.
4) Lower the rear of your car to allow the car to run FLAT, no rake!
5) Drive the car as you would a real race tire with as little sliding as possible but concentrate on using the additional side grip and better braking advantage the R-888 has over the RA-1. That's just to start with. Ultimately, a change in sway bar settings may be beneficial.
If you can't get the tire up to 45-47 lbs, start with a HIGHER pressure.
Ultimately, I believe that you will find that about 3 to 3.5 degrees of negative camber will do the trick and with little or no toe out in the front and little or no toe in for the rear.
This should to the trick. Let me know if I can help you.
Thanks,
Ron Cortez
Originally Posted by Spec Miata Community
Hope Ron doesn't mind me sharing this with all of you..
Ok, here's the deal on the R-888's.
I'd advise you one and all to TRY the suggestions I will make and then make a decision as to the speed and durabilty of the R-888 Vs the Ra-1 AFTER you try these new ideas.
But only AFTER you try the new settings.
A bit of History:
I first experienced excessive wear and bad handling of the R888 at the 2007 NASA 25 hour race on Mike Quan's Honda Civic with Roger Foo at the wheel.
Great team, excellent drivers. They came down in the middle of the night to ask if I could look at a tire issue they were having. Seems that TOYO had given them some new 888's to 'try' in the 25 hour race. First off, during a race is the WRONG time to try anything NEW. Let alone sort out a new tire. But, it was what it was and these things happen.
The issue was the car was pushing (front wheel drive car) and was wearing out the centers of the tires at an alarming rate. Well, one look at the worn centers and I suggested LOWERING the pressure. We did. And they began to wear out QUICKER and the handling became worse! It made no sense to me whatsoever.
Fortunately the team had enough RA-1's to complete the race and never put the R-888's back on the car. But, that adjustment in air pressure SHOULD HAVE worked. It had for years on all types of tires. But it didn't and it stuck in my mind over the winter.
The start of the 2008 season:
In the NASA races the BMW E-30 class cars were allowed to run either the RA-1 or the R-888 until June of 2008. Most jumped to the R-888 right away.
But that deal about the tire wearing out quickly in the middle still bugged me. So, I kept an eye on them.
Early on I asked Donny Edwards to allow us to 'try' something on his E-30. At Thunderhill we sent Donny out at 40 lbs STARTING pressure! He had already raced on them with the normal RA-1 starting pressure of 32 lbs, ending at 40lbs hot and was doing well. But, now I was asking him to START at 40 lbs.
His comment after coming off the track was that the car felt more stable and quicker. His times proved that he was correct. We kept an eye on Donny's car during the year and asked if he was getting any excessive wear. Donny's comment was that the car was used not only for the E-30 practice, qualifying and races but for every available session during the weekend. And no, they didn't wear quicker.
With this knowledge I then asked a HPDE driver, another trusted friend, if he would go out at 40lbs cold in his Porsche All wheel drive 911 Turbo. The thing weights a ton! He had already been out for 2 sessions at the lower RA-1 pressure setting on his new R-888's and LOVED the tires. Now, I was asking him to go out at a starting pressure of 40lbs. "Are you crazy" he asked. Maybe, but just try it for me.
His comment in coming off of the track was "I thought they were hooked up this morning with the lower pressure, but now they're REALLY hooked up." He loves the R-888 tires.
I'm relating these stories to help you all understand that I didn't come by these very unusual pressure settings without some forethought, testing on various cars with different drives and then analyzing the results.
Last story. At the NASA banquet one of the E-30 competitors came up and said that he finally put the pressure up to where I suggested at the last race. I asked how it worked for him. He said that he had turned a lap only 1/10th of a second off of Donny Edwards fastest lap. I asked why he had not done that earlier in the year and he stated that he just couldn't believe that pressures that high would work. Even though HE had maintained Donny's car all year and knew exactly what we were using for starting pressure!
Asked how high the air pressure was that he used before, he said that he had started them at 38 and they went to about 42-44 hot. But, that the hot pressure Donny ran was 45-47. He stated that he could not believe the difference that 45-47 hot pressure made on his car. That it just came alive. 2-4 lbs in hot pressure does make a difference.
E-30's wear? Even across the tire! Heat cycle 0. Wear rate: same as or better than the RA-1. How long do they wear? Down to the cords, just as the RA-1s did.
We've used these same pressure settings for a Porsche 996 Cup full race car that normally races on Michelin or Yokohama slick tires and with the same results. No heat cycling, no excessive wear and totally fun and drivable.
SM competitors, the R-888 has a different construction. A huge change in the design of the tire. You must make some changes to:
1) Your driving style
2) Your air pressure settings
3) Your chassis setup
To get the most out the new R-888's.
Staying with the same old setup, same old pressure and same driving style will not prove beneficial.
My suggestions:
1) Start with the exact chassis setup you have with the RA-1
2) Start the R-888 with 40 to 42 lbs of pressure.
3) Look for 45-47 as your hot pressure goal.
4) Lower the rear of your car to allow the car to run FLAT, no rake!
5) Drive the car as you would a real race tire with as little sliding as possible but concentrate on using the additional side grip and better braking advantage the R-888 has over the RA-1. That's just to start with. Ultimately, a change in sway bar settings may be beneficial.
If you can't get the tire up to 45-47 lbs, start with a HIGHER pressure.
Ultimately, I believe that you will find that about 3 to 3.5 degrees of negative camber will do the trick and with little or no toe out in the front and little or no toe in for the rear.
This should to the trick. Let me know if I can help you.
Thanks,
Ron Cortez
10-08-09, 12:00 PM
#91
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yep, donny is the high pressure guy. interesting that came from OUR group...
donny is fast, but he is also very very smooth, he's not out there sliding around heating up the tires. he's faster than everyone else, no matter the tire pressure.
we ran spec E30 in 08 with "low" pressure (that's what the tire temps wanted! slightly less camber too). once we got ours to actually run on 6 cylinders, we actually put it in the winners circle...
so for tommy's driving style, the low pressure works fine, we dont get that wear that ron is talking about (although i have seen it in the used tire pile)
donny is fast, but he is also very very smooth, he's not out there sliding around heating up the tires. he's faster than everyone else, no matter the tire pressure.
we ran spec E30 in 08 with "low" pressure (that's what the tire temps wanted! slightly less camber too). once we got ours to actually run on 6 cylinders, we actually put it in the winners circle...
so for tommy's driving style, the low pressure works fine, we dont get that wear that ron is talking about (although i have seen it in the used tire pile)
10-09-09, 12:04 AM
#92
Well the results are in, 4 seconds quicker on a damp track ... not too shabby, had it been dry and sunny all days I can see atleast another second or 2. But I was a few tenths off a 3rd and second gen, also there was an STi and a skyline that ran only 1 second below my time. So I'm finally getting in with the big boys. I was that I'm not allowed to run with the Novice group anymore 
... I'm too "experienced" now they're telling me. I had to hassle with them for about 10 minutes that day for them to put me in the Novice.
... I'm too "experienced" now they're telling me. I had to hassle with them for about 10 minutes that day for them to put me in the Novice.
10-09-09, 11:13 AM
#93
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4 seconds is a LOT...
10-09-09, 12:33 PM
#95
No rubbing on the inside, the front still clears the springs, not very much but enough. The only rubbing that I'm seeing right now is the front on the outside edges under heavy breaking and a bit of turning (ie trail braking into the turns) but thats about it.
