15" Tire Recs for 1974 911

[cbrett]

Hey everyone,
I posted up some questions previously after getting my new, old 911 and got some great help. I have decided to stick with the stock 15" Fuchs. I am trying to figure out which tires to go with and after searching through the forums, I have found mixed reviews.

I am thinking of going with Sumitomo HTR A/S P02, a high performance all season tire. Currently the car has 205/60/15 tires all around on it. Any thoughts on this specific tire and sticking with that size versus bumping up to a 215/60/15. Thanks and here's some pics of the car now. Just replaced the 993 seats with some Classic Touring Seats.

[dwelle]

original flares on the back? looks like 6 & 7's.

if NB flares, the 215 will be a tight fit, and may likely rub without a fair bit of negative camber. also, the 215/60 is a tall tire, over 25". if you have the original 2.7, a smaller tire will really help acceleration.

i have a '76 with the same wheels and original narrow flares. i run a 205/55-15 all around on 6 & 7's. i tried 50's, but they were just too short for how i use the car. really happy with the 55's, nice compromise for what is effectively a daily driver set up for good performance...

[cbrett]

Gorgeous car. The stance looks just right on it. What tires do you run?

That's some great info. Yes, NB with 6's and 7's. It has a 3.0L engine from an SC and is pretty peppy.

[dwelle]

yokohama S-drives. i believe that they’ve just been discontinued and replaced with a newer model, the ADVAN v701. no experience with those.

another suitable choice is the dunlop direzza dz102...

[Ginger77]

Both are beautiful rides! But I love how that 55 aspect ratio gives a meaner look and stance.

[Arne2]

I have the Sumitomos on my '72, but in 195/65-15 size. I'd call them 'adequate' tires. Not great, but adequate. I'd also recommend not trying the 215/60s, they are a bit too wide to be good on 6" wheels in front, and prone to rub on the 7" in back.

[Inkblot]

I'm running 6 and 7x15s, 205/60 fr and 215/60 rear on my '75. I've found that the 215s on the rear work fine, but you have to be a bit careful with the toe-in setting; increasing the toe-in actually pulls the wheels outward, and they will rub. I went with all-season Falken Ziex ZE950s, as they were one of only a few brands which had the offset sizes.

Having run this setup for a while now, I'd say the tires are pretty good all around, but not great. I'm also thinking about trying 7's up front. Visually, I'd like to find something that fills the rear wheel wells a little more, but it's a game of millimeters before something starts to rub.

Check out this thread for some great info:

https://forums.pelicanparts.com/porsche-911-technical-forum/1013266-what-wheels-work-best-77-911-non-flared-fenders.html

- Jake

[911pcars]

Originally Posted by Inkblot

I'm running 6 and 7x15s, 205/60 fr and 215/60 rear on my '75. I've found that the 215s on the rear work fine, but you have to be a bit careful with the toe-in setting; increasing the toe-in actually pulls the wheels outward, and they will rub. I went with all-season Falken Ziex ZE950s, as they were one of only a few brands which had the offset sizes.

Having run this setup for a while now, I'd say the tires are pretty good all around, but not great. I'm also thinking about trying 7's up front. Visually, I'd like to find something that fills the rear wheel wells a little more, but it's a game of millimeters before something starts to rub.

Check out this thread for some great info:

https://forums.pelicanparts.com/porsche-911-technical-forum/1013266-what-wheels-work-best-77-911-non-flared-fenders.html

- Jake

The 215/60-15s on the back have some potential for paint damage. Good you haven't experienced it yet.

I had that same wheel/tire size combo on my factory-bodied '69 years ago (same profile as your '73), but Pirelli P6. They were fine for regular street cruising. However, after some spirited "driving" in nearby mountain roads, I discovered half-moon shapes of burned paint about 2" above the wheel well, both sides. You may be fortunate since tire dimensions vary a bit from brand to brand.

Sherwood

[Bill Verburg]

Originally Posted by 911pcars

The 215/60-15s on the back have some potential for paint damage. Good you haven't experienced it yet.

I had that same wheel/tire size combo on my factory-bodied '69 years ago (same profile as your '73), but Pirelli P6. They were fine for regular street cruising. However, after some spirited "driving" in nearby mountain roads, I discovered half-moon shapes of burned paint about 2" above the wheel well, both sides. You may be fortunate since tire dimensions vary a bit from brand to brand.

Sherwood

I had the same experience w/ my '72 w/ 7-215/60x15

215/60 is too tall and thus has a high inertial & gearing cost

good choices are
185/70@25.1" on 6
195/65 @25.1" on 6 or 7
205/60@24.7" on 6 or 7
205/55@23.9" on 6 or 7

if using staggered sizes try to match heights as much as possible

[Inkblot]

Originally Posted by 911pcars

The 215/60-15s on the back have some potential for paint damage. Good you haven't experienced it yet.

Sherwood

Well, while I haven't experienced it yet, the car certainly has! I've definitely got that telltale paint blistering above the wheel arches, but that's due to the PO running 225's on 16X7in wheels. Those things rubbed like crazy!


Jake

[Inkblot]

Originally Posted by Bill Verburg

I had the same experience w/ my '72 w/ 7-215/60x15

215/60 is too tall and thus has a high inertial & gearing cost

good choices are
185/70@25.1" on 6
195/65 @25.1" on 6 or 7
205/60@24.7" on 6 or 7
205/55@23.9" on 6 or 7

if using staggered sizes try to match heights as much as possible

@Bill thanks for your notes- I've used your other posts and spreadsheet as a guide in the past, they're super helpful.

Quick question, at risk of highjacking this thread... why is 215/60 too tall? If I'm doing the math correctly, the original stock wheels (185/70) had a total diameter of 25.20", where the 215/60's are 25.16". I understand that a smaller total diameter would have some benefits in gearing, acceleration etc. (not to mention clearance), but I think I'm just under the original stock diameter.

Cheers-

Jake

[Bill Verburg]

Originally Posted by Inkblot

@Bill thanks for your notes- I've used your other posts and spreadsheet as a guide in the past, they're super helpful.

Quick question, at risk of highjacking this thread... why is 215/60 too tall? If I'm doing the math correctly, the original stock wheels (185/70) had a total diameter of 25.20", where the 215/60's are 25.16". I understand that a smaller total diameter would have some benefits in gearing, acceleration etc. (not to mention clearance), but I think I'm just under the original stock diameter.

Cheers-

Jake

First tires can vary a bit from their nominal specs so all 215/60x15 aren't going to be exactly the same, there will usually be some small variation from one brand to another.

second its the combination of height and width that determine fit( not to mention wheel width and ET), extra clearance can be gotten by using more neg camber, by raising ride height and by limiting suspension travel(usually by using stiffer suspension)

[Inkblot]

@Bill: thanks- yeah, makes sense from a clearance perspective- definitely need to consider both height and width.

I was responding more to your comment about the tires being too tall from a gearing perspective (assuming clearance is ok), as it looks to me like the final ratio of the 215/60s should be same as stock.

I’m any case, the 215/60s have definitely proven to be too tall to provide any range of camber and toe-in adjustment. I had to fiddle a lot to find the sweet spot- there’s just no room for any changes to the settings (in pursuit of better handling, etc). For me, that’s reason enough to try something new soon!

Jake




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[Bill Verburg]

Originally Posted by Inkblot

@Bill: thanks- yeah, makes sense from a clearance perspective- definitely need to consider both height and width.

I was responding more to your comment about the tires being too tall from a gearing perspective (assuming clearance is ok), as it looks to me like the final ratio of the 215/60s should be same as stock.

I’m any case, the 215/60s have definitely proven to be too tall to provide any range of camber and toe-in adjustment. I had to fiddle a lot to find the sweet spot- there’s just no room for any changes to the settings (in pursuit of better handling, etc). For me, that’s reason enough to try something new soon!

Jake




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In my data base I have 5 215/60x15 tires listed the Od's range from 25.0 to 25.6, I also have 5 185/70x15 which range from 25.1 to 25.4"

inertial cost depend on weight and OD, generally the taller the tire the larger the inertial cost
gearing cost depends only on OD, but the nominal OD is usually greater than the actual loaded OD(manufacturers vary in this regard) each tire flattens on the bottom to a greater or lesser extent, to see how much a tire flattens you need to do a roll out or at least use the manufacturers rev/mi data

I've arbitrarily divided tires in my mind into good w/ OD < 25" and bad > 25". I choose 25 because that is close to the nominal height for 185/70x15

[Inkblot]

Awesome- thanks, makes sense!


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[PRE-H20]

I have 225's on 15's on a STOCK 74........ NO RUBBING.....

[PRE-H20]

Stock Flares (so pretty much no flares)

[stcan]

Originally Posted by PRE-H20

Stock Flares (so pretty much no flares)

Nice wheel and tires fitment.

What's the width and offset of the wheel. And the tires size for front and back tires

[PRE-H20]

Thanks.....

The front

Fuchs are
15x7
Tires are
205 50 15

The Rears

Fuchs are
15x8
Tires
225 45 15

Im not sure of the offsets.

BUT what makes my suspension work is the geometry reconfiguration wizardry Tyson did.

No rubbing at all, tightly tucked in under the wheel wells.

[TrickySF]

PRE-H20-What brand tires are you using on your 7' and 8's. I have not found a tire set that provides the 225/45/15's? No problem finding the 205/50/15.