Current best tire/size for 15x7x8 DE/Street SC?

[euro911sc]

Just rebuilt my ROW SC engine so on to long forgotten projects

I may have a line on a set of 15x7/8s locally that I would like to use instead of my 16x6/7s...

What are you guys/gals running on your 15's for a DE/Street tire? what is the best size: 7s-> 205/215 8s->225/235 ?

Best regards,

Michael

[joetiii]

I have 205/50 Falken Azenis 615 on my 7 inch rims. No rubbing up front. Not sure how many 215 sizes there are still available, but I think they would fit the 7s w/ no rubbing. I believe you can fit 225s on the rears but have no personal experience.

[DCOP]

I'm running BFG's 205/55's front 225/50's on rear with RS flares. Recently purchased from Tirerack. Good price nice tire.

[911st]

Notables:

Toyo R888's 235/50/15 & 225/50/15.

Michelin Pilot Sport Cups 225/50/15's for all four. Not to short and very light.

Hoosier 245/50/15 & 225/50/15's


205/50/15's seem very very short to me.

[euro911sc]

911st: 235 or 245 on an 8" rim? does that really fit? I know 225 on the 7 should be good. I'd really consider the 235/245 if the fit was good...

I scoured Tire Rack and Discount Tire this afternoon... 205/225 are the only sizes I could find matching front and rear tires:

205/50/15 and 225/45/15 Hankook Ventus R-S2's both for just under $100 ea.

or

205/50/15 and 225/50/15 BFG g-Force Sports - also just under $100 ea.

It seems virtually impossible to find the same performance tire in multiple widths for 15 or 16" diameters these days... such a bummer...

[euro911sc]

R888's would be nice, but man... they're gonna go fast and at what $150 each my wife would kill me every 6 months

-Michael

[911st]

Not an expert but for a DE street tire the R888's are going to be your best and yes the 235/225s are in the recomended rim size for your rims.

The issue w 15's is how tall they are. A stock 911 wheel should be very close to 25". If you go w a 205 front you will be about 2" shorter than stock.

If you are going on the cheep, I would just run 4 225/50's Hankooks all around. The are approved for a 7-8.5" rim and are not crazy short at 23.9".

Many guys w 7" rims run 225/50's on all four with the narrow body cars. I did so on my 72 S. But you will have the added advantage of wider rear rims.

If you go all 225's you can run a stiffer front sway bar if you want. This will make the rears stick even better. You can get a 22mm bar from a 86 Carrera or a 22mm Weltmister adjustable.

A good thing about the 15 Fuchs is they weigh about 20 lbs less in total over the 16's plus you get a little gearing advantage w the shorter tires.

[Bill Verburg]

Originally Posted by 911st

Not an expert but for a DE street tire the R888's are going to be your best and yes the 235/225s are in the recomended rim size for your rims.

that is your opinion and you are welcome to it.

You can run R rubber on the street but it doesn't last long and the car needs to be setup for it, w/ lots of camber and caster. you can use several sizes successfully, it depends on your needs.

Hankook has a nice tire that is more street biased. It is a price point tire and not as well received as some other tires but it does come in the right sizes for 7 & 8 x15
you can use 205/50 & 225/50 x15 this was oem Carrera sizing in '76
or 205/50 & 225/45 x15 for a bit lower gearing

MPSC is an excellent track biased tire that needs a chassis set up for it, lots of camber and caster
205/50 & 225/50

Toyo 888 and RA1 can be sized as w/ the Hankooks, but again it's R rubber and needs a chassis set up for it

888 can be used 225/50 & 235/50

Kumho Ecsta V70A is another R rated tire, that wants the chassis set up but can be sized like the Hankooks

I would avoid using 225/225 unless you are doing A/X, your car will oversteer more(unless you make other compensating mods) w/ that sort of sizing

Originally Posted by 911st

The issue w 15's is how tall they are. A stock 911 wheel should be very close to 25". If you go w a 205 front you will be about 2" shorter than stock.

tire height depended on the year early cars w/ 185/70x15 tires @ ~ 25.7" tires, '73RS 215/60 x15 @ ~ 25.1", in the mid 70s low profile tires became widely available and 225/50 x15 @ ~23.8", then for the SCs they settled on 225/50 x16 @~24.7"

what difference does it make,
1) speedometer reading
2) gearing & the speed at which max torque or hp occurs, shorter moves the peaks to slower speeds and taller moves the peaks to higher speeds
3) appearance, the shorter tires will want and will allow the can to run lower, the taller will want and require the car to run higher.


The owner needs to make some decisions as to the compromises he wishes to make.

[911st]

Listen to Bill.
Like I said, I am not an expert. Just my opinions.

[euro911sc]

Excellent info gents! This was the answer I was looking to get. In the near term, I'll be running mostly street so, while I would really like to use an R compound, it may not be practicle. Currently, I have a 26 year old suspenstion as well so I would probably loose anyd R compound gains in the suspension to boot I'm working on that one! So I will be looking into the more street targeted tires to start with.

I like loosing unsprung weight.

I'm not concerned about the changes in gearing or speedo as they are in a direction I want (gearing torq + to offset the bigger headers I have on, speedo saying I'm faster than I really am)

I guess the final question would be a performance question: 15x7/8 vs 16x6/7...

http://forums.pelicanparts.com/showthread.php?p=4244064#post4244064

Best regards,

Michael

[DennisMenace]

Originally Posted by Bill Verburg

that is your opinion and you are welcome to it.

You can run R rubber on the street but it doesn't last long and the car needs to be setup for it, w/ lots of camber and caster. you can use several sizes successfully, it depends on your needs.

Hankook has a nice tire that is more street biased. It is a price point tire and not as well received as some other tires but it does come in the right sizes for 7 & 8 x15
you can use 205/50 & 225/50 x15 this was oem Carrera sizing in '76
or 205/50 & 225/45 x15 for a bit lower gearing

MPSC is an excellent track biased tire that needs a chassis set up for it, lots of camber and caster
205/50 & 225/50

Toyo 888 and RA1 can be sized as w/ the Hankooks, but again it's R rubber and needs a chassis set up for it

888 can be used 225/50 & 235/50

Kumho Ecsta V70A is another R rated tire, that wants the chassis set up but can be sized like the Hankooks

I would avoid using 225/225 unless you are doing A/X, your car will oversteer more(unless you make other compensating mods) w/ that sort of sizing




tire height depended on the year early cars w/ 185/70x15 tires @ ~ 25.7" tires, '73RS 215/60 x15 @ ~ 25.1", in the mid 70s low profile tires became widely available and 225/50 x15 @ ~23.8", then for the SCs they settled on 225/50 x16 @~24.7"

what difference does it make,
1) speedometer reading
2) gearing & the speed at which max torque or hp occurs, shorter moves the peaks to slower speeds and taller moves the peaks to higher speeds
3) appearance, the shorter tires will want and will allow the can to run lower, the taller will want and require the car to run higher.


The owner needs to make some decisions as to the compromises he wishes to make.

Hi Bill.

Trying not to open too many new posts. Trying to comment on older posts that covered the same topic. I also plan to run R888Rs. What do you consider „being set up for it“? I am planning a suspension rebuild with 22/29 mm torsion bars, KW V3 suspension, all around new sport rubber bushings, turbo tie rods. Planning to run 225/50 and 235/50 R15 front and back. Do you consider this set up for R compound tires?

Best, Dennis

[Bill Verburg]

Originally Posted by DennisMenace

Hi Bill.

Trying not to open too many new posts. Trying to comment on older posts that covered the same topic. I also plan to run R888Rs. What do you consider „being set up for it“? I am planning a suspension rebuild with 22/29 mm torsion bars, KW V3 suspension, all around new sport rubber bushings, turbo tie rods. Planning to run 225/50 and 235/50 R15 front and back. Do you consider this set up for R compound tires?

Best, Dennis

What are you using the car for?

22/29 w/ short sidewalls is going to have a poor ride for general street use but would be good on track

KW being a twin tube shock will take some of the pain away on the street but isn't going to be as good on a track.

888s, RA1. NT01 are street able but slick as snot in the wet and want more camber for track use, Something like RE-71RS is a much better choice for dual use.

225/50 & 235/50 on Fuchs 7 & 8 is a decent track choice, and is street able but to get the most from them you'll want to run more camber , like maybe -1.5-2 front and -2.5-3 rear. these will wear quickly in street use and again be slick when wet.

car will also want to be low in the 140-160mm(a -b) range where you will want raised spidles and at least rack spacers and possibly adj height steering knuckle.

[DennisMenace]

Hi Bill.

I plan to use the car on sunny days for spirited mountain / canyon driving + some DE events occasionally. We have quite some smooth roads here in Germany / Austria for the most part.

After what I read on other post in other threads from you I am thinking 21/27 or even 20/26 might be more suitable for me? I am currently running the stock 19/24 bars.

Thanks for your help.

Best,
Dennis

[Bill Verburg]

Originally Posted by DennisMenace

Hi Bill.

I plan to use the car on sunny days for spirited mountain / canyon driving + some DE events occasionally. We have quite some smooth roads here in Germany / Austria for the most part.

After what I read on other post in other threads from you I am thinking 21/27 or even 20/26 might be more suitable for me? I am currently running the stock 19/24 bars.

Thanks for your help.

Best,
Dennis

if the roads are smooth then 20/27, or 21/29 are good if you want a bit less under steer
21/27, 22/30 for a bit more

wheels and tires affect this as well so that has to be considered as well as hp

I went w. 20/26 because roads here can be poor often enough, I have much bigger rear wheel tires than stock, I have much more hp than stock,