New Hoosier A6 275/35-15 !!!!

[xelderx]

If and when you do get around to this, I'll buy your Hoosiers off of you

Ok...You want the Koseis too? The offset isn't ideal for the Proteges, but it's the only thing TireRack had at the time. I guess I don't have to explain it to you....you've seen them. The tires are still good. Took 2nd place in Pro class at the last event of the season on them.

 

[miata_racer]

Your car is the only one fat enough to make good use of this tire. Better not let me down on this one

You gonna come to Walnut Ridge for the tour this year I hope? I'll be racing with my dad in AS in the Boxster S

It's a fun event man.

The new size which has been approved for production, is the P275/35ZR-15 A6. The diameter will be 22.9" with a tread width of 10.3". On a 9.5" wide rim, the total width should be 11.25". This tire will be used on a 8.0" - 10.0" wide rim.

Release scheduled for late February/ early March.

I've got to get a 15X10 rim now so I can start doing some test fitting.

 

[xelderx]

Your car is the only one fat enough to make good use of this tire. Better not let me down on this one

You gonna come to Walnut Ridge for the tour this year I hope? I'll be racing with my dad in AS in the Boxster S

It's a fun event man.

There is a good chance I'll be at Walnut Ridge. Depends on the funds. I need a little redemption against the Boxster. I outran him in August, but Rob Faulkner put his a few tenths in front of me at our last event.

 

[khaosman]

Ok...You want the Koseis too? The offset isn't ideal for the Proteges, but it's the only thing TireRack had at the time. I guess I don't have to explain it to you....you've seen them. The tires are still good. Took 2nd place in Pro class at the last event of the season on them.

Nah I'll just use my Rotas. I was thinking about using one of 'em for summer use wheels but I think I'll just hold out and get 16s. Let me know how much you want and when you are going to get rid of 'em.

I can't wait to see what your car looks like next year, or even better, to drive it again. 275s on 10" wide wheels... that will probably feel like driving a tank or something I can't even imagine. I'd probably be pegging cones everywhere.

 

[Vanimaniac]

Hey Justin, I know you've already ordered your wheel from Diamond racing but I just did a search for "15x10" on ebay motors and had 4 pages of hits. Most of the wheels are for jeep wranglers, ford rangers, etc. which have the same bolt patterns as our protege5's. 5x114. Backspace I'm not so sure.

Not sure if you or anyone has checked that route but thought I'd mention it.

Van

 

[xelderx]

Hey Justin, I know you've already ordered your wheel from Diamond racing but I just did a search for "15x10" on ebay motors and had 4 pages of hits. Most of the wheels are for jeep wranglers, ford rangers, etc. which have the same bolt patterns as our protege5's. 5x114. Backspace I'm not so sure.

Not sure if you or anyone has checked that route but thought I'd mention it.

Van

I scan through there about every other day or so. I was really worried about getting the backspacing right

 

[xelderx]

That might end up being my new wheels. 15x10"...15.5lbs...$250ea.

 

[Rogue]

ooo...shiney. are those the diamond racing?

 

[xelderx]

ooo...shiney. are those the diamond racing?

Those are actually Spinwerks.

http://www.racerpartswholesale.com/spinwerks.htm

 

[xelderx]

My 15X10 Diamond rim came in today. It's really nice, just a little heavy. I don't have pictures at the moment. I didn't have my camera with me. I did bolt it up front and rear to see how it cleared everything.

I ordered it in 6 1/2" backspacing. This appears to be the maximum backspacing that can be used on the Proteges as it only clears the AWR struts by about 1/4".

I left my 3mm spacer on the rear and it cleared the back brake caliper easily. It was extremely close to the lower spindle mount nut though. If you look at the car from the rear there is the long bolt that goes through the lateral links and the spindle. It sticks out a little in the back and the rim was only a few millimeters away from it. It is inside of the bead area so I'm not worried about the tire getting into it. Rim flex might be an issue there, but I have a feeling I'll need to space the rim away from the struts a little farther for clearence once I have the tires mounted anyway.

On to the front end. I was able to mount the rims up without the 15mm spacer I have without any rubbing. Strut clearence was aboutthe same as the back. The only thing that might be a major issue once the tires are mounted was the the front brake line bracket. It's the bracket connected to the inner fender where the hard brake line meets the flexible one. I have a feeling that the tire will rub against this at full lock. It will be a sharp edge right on the sidewall. I'm going to cut out a few pieces of wood to the width dimensions Hoosier is giving and tape them to the rim since it will be another 2 months before the tires are actually available.

 

[Vanimaniac]

Let's hope they really do go through with this new tire size!

Calmly waiting for pics of the wheel mounted.

van

 

[gavin_leslie]

Given how low your TQ is coming on maybe the shorter tires and a short shift to 3rd would work better for you?

From this tread.. http://www.msprotege.com/forum/showthread.php?t=123656969

Ive decided to do a bit of math on this as Moxnix's suggestion is very very interesting. With the previous selection of tires and the lessons you learn that shifting is bad, this was an unacceptable option....but now?

Lets see, stock dyno says that I make 144hp@4250rpm and 192ft/lb@3500rpm. The HP curve us a broad plateau while torque is a rather steep peak(kinda the opposite of everything else you see). Engine starts getting asthmatic @5000rpm, redline @6250rpm.

The math says that with 205/60/15s in 2nd gear @6000rpm (1.772 with FD 4.105) Im doing 60.5mph. Same thing with 245/45/16 Hoosiers. Problem is Im way past the fat of the torque and HP peaks. The GS car is using 225/50/15 V710s. They are 1" shorter than the stock tires..that nets me 58.5mph in 2nd. I have found myself between gears many times as this engine isnt a free revver like the F-series and doesnt really net any more speed winding it out. 3rd with 225/50/15s nets me 87mph @6000rpm...but @4500rpm Id be pulling 65mph.....hmmm.

So if moxnix is right, saying I should damn the torpedoes and go for 3rd with even shorter tires, lets see what happens. 275/35/15 would be 2.2"shorter than stock. 2nd gear would be 55.4mph @6000, but if I do a shift to 3rd, @4500rpm I get 61mph right in the heart of the power/torque.

Smaller diameter tires, less weight, lower CG, higher roll centers, better suspension geometry, wider tires for a "heavier" car.......theoretically better gearing. Im liking this...a lot. I may be selling a set of CCWs soon.

Ill be doing some back to back testing with the GS car with the 225/50/15 V710s and 225/45/15 Hoosiers(almost the same diameter as the 275s) to see how the car responds to a 2-3 shift.

Gavin (really REALLY interested in 15x10s now)

 

[xelderx]

Teaser pic. The rest will be up in my build thread in a little bit.

http://www.mazdas247.com/forum/showthread.php?t=93704&page=35