Turbo flares vrs. RSR flares

[Lorne Ross]

I am confused about the differences between the Turbo flares and RSR flares. As I have installed turbo flares on the rear of my 1973 911T, I am trying to figure out what size wheel and tire I can use. Everything I read when I do a search just talks about the size of wheel and tires for the RSR flares. Can anyone smarten me up.

Thanks alot.
Lorne Ross

[klaucke]

The turbo flares are basically the same size as the RSR flares, 9" front and 11" rear. This as opposed to a 9" rear flare for a standard SC/Carrera. The shape of the RSR flare may be slightly different, i.e. the lip has more of a curve to it, rather than the flat side of the edge of turbo flares. Turbo's were stock with 9" rear rims and 225 width tires I believe.

People have fit many, many different size tires under the RSR/turbo flares. It depends on many factors, such as wheel size, width, offset, oil line location, bolt shaving, fender lip, ride height, spring rate, etc.

I would use the RSR flare information you're finding to get an idea of what you'll need, and then proceed from there. What exactly is the car going to be used for?

[Jack Olsen]

Yup. They both basically allow the same width of wheel (depending on how they're installed). This means with a little effort, you can usually fit a 12-inch wheel with 335 mm tires. The offset and backspacing will depend on your hubs and brakes.

[911teo]

We are just finishing welding Turbo flares on my Carrera. I went with an 11' wheel and 315 tire... But I think I was a little conservative...

As Jack said I think there is enough room in there for a 12/335 combo. Just make sure you specify the correct offset when selecting the wheels.

We are running the smallest possible spacers that clear Brembo GTP calipers.

[Jack Olsen]

I also run 11's and 315's. It's a lot of tire.

[dweymer]

I will never get tired of looking at that view.

[ted]

Turbo flare with 17x12 and 335/35.
As Jack said they fit with a little work .
They are scary over standing water!

[DW SD]

Ted,
What size are your fronts on the black car?

Doug

[ted]

Hi Doug,
17x9.5 rim 275/40 tire.
I use the stock 16x7 and 16x9 Fuchs for the rainy months.

[911teo]

Hey Ted I went with 17x9.5 275/40 as well... but my car is not ready yet. How is the steering feel?

My biggest doubt was that so much rubber in the front would take away some of the "tossability" of the car...

[ted]

Certainly the steering effort for a wider front tire will be greater.
I've only pushed it a couple times, but the car is still very nimble.
Throttle steering a 270' on ramp is still a blast.
If the steering effort were an issue (longer races) they do make a power steering kit for a wide body 911.

When I AX it I use stock rims (7s and 9s) with less expensive street tires. Just so I don’t flat spot the more expensive and wider daily driver Michelins. As far as AX I noticed a wide body makes the track noticeably narrow.

The front tires on Jack Olsen's wide body are almost as big.
Jack what was your opinion regarding toss-ability comparision between BB1 and BB2?

[Jack Olsen]

I run 255's in front, and my front suspension is modified so that the scrub radius is actually better than a skinny-tired early car. My steering is very nimble; it probably isn't representative of most 911/930's.

With the Turbo's worse-than-average scrub radius, you'll notice the increased steering effort at low speeds more than high speeds. Also, the wheel will pull away from you more under hard braking on uneven surfaces.

But the increased grip will make you forgive all that, I'd guess.

[ted]

Originally posted by Jack Olsen
Also, the wheel will pull away from you more under hard braking on uneven surfaces.

For real. When I hit standing water my steering wheel pulls a good quarter turn, but the car for the moment still tracks/hydroplanes straight.
The car for a moment seemingly not requiring a correction yet you feel like you need a rudder or bow thrusters!
Wheel cranked a good quarter turn and the car hasn't twitched...get back to center quick!
Now that I'm prepared for it in the rain I hold the wheel tightly with both hands.

[304065]

Originally posted by Jack Olsen
my front suspension is modified so that the scrub radius is actually better than a skinny-tired early car * * * with the Turbo's worse-than-average scrub radius, you'll notice the increased steering effort at low speeds more than high speeds.

Interesting, Jack. Without giving away too much to your OTC competition, what did Tyson do?

Scrub radius is defined as the distance between the point where the steering axis inclination (basically the centerline of the strut) intersects the ground and the centerline of the wheel's contact patch.

That means that to reduce the scrub radius, you move the wheel centerline in toward the middle of the car, with increased offset, which would narrow the track, or a narrower wheel.

Now, the other way to do it would be to reduce the angle that the strut makes from vertical (e.g. vertical strut would be 90 degrees, less would be 85, even less would be 75 degrees) by moving the strut top inward with a weld-in camber box. Or you could lengthen the control arm, moving the strut bottom out?

[Jack Olsen]

Originally posted by john_cramer
Or you could lengthen the control arm, moving the strut bottom out?

Tyson extended the control arms by 1.5 inches (35mm), modified the control arm mounting points in front and the strut mounting point up top. When the struts were getting made, they asked us how much stati negative camber we'd like built in. Because of our new geometry, we actually had to have them put in positive camber.

You'll notice that the hubs are farther out on my car than you'd see on a Turbo, which pushes the wheel out with spacers.

[vdavie]

I just bought the silver RSR clone and it has 335's on the rear, it rubbed a bit this weekend when i was driving it hard.

vince

[AbbyAk]

Put Lindsey Racing RSR finish 8" s and 11"s on my 84 Factory Turbo -look Coupe. Had some fitting to do as the spacers pushed the wheels out a just a smidge past the fender edge. Had spacers machined down a bit, and had to switch to the steel "through" lug-nuts.
The look is awesome. I went with 8"s up front as all they can make now is 9.5"s and did not want to shove those under...

[Lorne Ross]

I would like thank all of you guys for your responses to my silly question. I plan to order 9.5 x 17 and 11 x 17 from Mike Lindsey, but I was not quite sure if I knew what I was doing. But now I feel very comfortable about ordering them. I finally got my P-car back from the body shop after almost a year and I am about to start putting her back together.
So once again thanks for all the help.

Lorne Ross
Caledonai, On.

[rbcsaver]

Jack,
I've said it before, I love looks of that car.

regards,
Steve

[Jack Olsen]

Thanks.