All else being equal, I think the 245/40 is probably the way to go, though I could be wrong. With the 275s, I wasn't using the full treadwidth between the narrow rim and limited camber, I was probably using more like 255 I'd guess, so a 245 wouldn't give up that much in terms of footprint. With the 710, the choice was 245/45 or 275/40; both were roughly the same height and weight, so I think the 275 is the right choice given those two options. Throw a 245/40 into the mix though, and the shorter sidewall, smaller diameter, and lower weight are enough I think to offset the advantages of the 275/40. WRT weight, it will be interesting to see what the 710 and A6 weigh in 245/40 form. The 245/40 A3S05 is 4 lbs lighter and 0.9" shorter than the 275/40 710 (on paper anyway). 4 lbs is a chunk of weight that far from the hub.

Oh yeah, and there's no rubbing with the 245/40

JW

 

Yeah, you SM guys have a whole different set of variables to work with, don't you?

I was expecting to see you in the results for the SD Tour. You have a good excuse, I trust

JW

 

Any updates from anyone on how their stock class tire decisions are working out? In my area, the start of the season is still a month away, so I still have a couple of weeks left to make a decision.

I did a test fit session today with my old 255/40 Victoracers, on RPF1s with a +35 offset on my 06 MR. The good news that I think 275/40s would fit up front, assuming that they are about 1/2 inch taller and wider than the 255/40s. The bad news is that 275s in the back might rub the fender lip on the shoulder. I ran one rear tire up on a ramp, and the 255 was just under a 1/2 inch away from contact. This was at factory camber settings with a +35 offset. Given that 275 would be an wider (1/4 per side) and taller (1/2 total), I think it might rub. On the other hand, this was with the rear tire about six inches in the air on a ramp, which is probably more suspension travel than you will see while accelerating and turning.

I don't think that the 245/40 Hoosier A6 is enough tire, or will wear well enough. Likewise for the V710 245/45 (especially in the front). If Kumho comes out with a 255/40, I'd go for it, but time's running out. I'm thinking that the 275/40s will be risky. I'm still considering a V710 275/40 - 245/45 hybrid setup. I read that Daddio decided that the ACD was working against the setup, but for a stock setup with a less power, and less grip, it might not be an issue.

All input is appreciated!

 

Has anyone tryied the 255/40 17 on stock MR wheels in an autocross? will it rub?

Will it work better than stock size?

 

I ran the 255/40 Victos on the 03 with no rubbing on wheels with 3mm less offset. Also, based on the test fitting that I did yeserday on the MR, the 255/40s should be fine.

Will they work better than stock - yes... will they work better than V710s or A6s - no.

 

Yes, no, yes.

 

Earlier in this thread I mentioned the Ohlins sport suspension. It is a stock strut direct replacement with 25 levels of damping. I purchased these struts from WORKS and installed them about a week ago. They do come with WORKS Ride Springs, but I used the stock springs to comply to the Stock class Solo 2 rules. According to my calculations, all of the dimensions of the struts also fit the Stock class rules.

A few pics of the fronts:


And the rears:


The whole set:

Front installed:

These 2 are pics of the hole I made in the trunk liner to get access to the rears adjusters:



My car is also my daily driver. I've been running them on the street for the last week on full soft. On full soft, the ride is a tad less harsh than the stock dampers.

I ran my first autocross with the new struts today. On my first run, I started out out with the dampening set @ 4F, 7R(the higher the stiffer). I didn't notice much difference from stock. I decided to crank them up to 18F 22R for the second run. The car's behavior had completely changed. It was so stable in transition it was hard to believe I was driving the same car. I went to 20F 22R to see if I could lose some time in the slalom for the 3rd run. The car felt a tad better and I dropped .8 sec. On the 4th I left it at 20F 22R and dropped another .5 sec.

The range of damping adjustment is really great. It is a tool to have in a class that doesn't allow many ways to change your setup.

 

Good review. I have the new Ohlins R&Ts and love 'em.

FYI, the convention is opposite to what you posted. In other words, use "clicks from full stiff" rather than "clicks from full soft."

 

This sounds great for autocross, but how does it comply with the scock class rule that adjustable shocks must contain only two settings, which span the range of the original stiffness (or at least that's how I interpret the rule)?

 

It looks like those shocks have one external adjustment control, which is legal.

The rule doesn't state that you can only have two settings, it states that you can only have two external adjustment controls, per shock.

So you can have eight "knobs" on the car (two at each corner), and there is no restriction on number of adjustment levels -- the shocks might be continuously adjustable, leading to an effectively infinite number of setting combinations, and it would still be legal.

The typical two adjustments permitted would be compression and rebound strength, although nothing would prohibit other combinations, such as slow-speed damper strength (for adjusting cornering behavior) and high-speed damper strength (for adjusting behavior on a bumpy surface).

Also, note there's no requirement that the shock behavior (in terms of stiffness) bear any similarity to the original shocks on the car. If you want to run shocks that are adjustable between 5 times as stiff as stock up to 15 times as stiff as stock, that's allowed.


Stock-legal cars in the past have used some very creative (but legal) interpretations of the shock adjustment rule -- in particular, cars have been run with ridiculously high rebound strength, which has the effect of holding the car's suspension in a compressed state. This has the effect of lowering the car simply by replacing the shocks (with other shocks of the same dimensions).

 

Ohlins recommends to start soft and go stiffer in their manual. That is how I started, but I didn't feel much of a difference from stock. Since we were only getting 4 runs and this was my first time playing with the damping adjustment, I made a big change. In my next autox I will start stiff and go soft like you said.

 

Now, correct me if I'm wrong, but couldn't you install the RS rear bar as a back dated component?

edit: Now that I think of it, is th RS bar a strut tower bar or a sway bar? Mitsu's website doesn't seem to be too specific about it...

 

No, there is no update/backdate in Stock classes.

You can do a complete package conversion of a base Evo to an RS Evo or to an MR Evo, or vice versa, but it's probably not worth the effort because you need to change EVERYTHING to match the target vehicle (except for those things which could be legally changed back to the original vehicle configuration). In Stock, if you want to run anything off the RS -- like the rear strut bar -- you need to make your car look like a factory RS. In particular, you'd need to install the aluminum roof from the RS and the non-ABS braking system from the RS, along with some other minor details...

Effectively, it's not an attractive proposal to switch between any of the three Evo configurations, because switching to or from the RS requires switching out the ABS/non-ABS braking system, and switching to or from the MR requires switching out the transmission. It's easier to go down to the Mitsu dealer and buy the car you want...

 

Figured I'd bump this thread and add my own experiences.

Here's my AS setup-

2005 Evo MR Silver

Alignment: -2.0/-1.9 Front L/R camber -1.2 L/R rear camber.... 1/16 toe-in Rear 0 toe, Front

Wheels - Stock MR BBS (Run regular Evo wheels on the street)

Tires: 255/40/17 RA-1

Locally, it's a competive car, moreso in other clubs which do not use SCCA classing. I have been PAX'ing fairly well until my last event running on 4 corded tires

I went with RA-1s - and continue to do so - due to the wear charastics of the tire. My wife and I autocross about 25 events a year, and 710s (and even 700's) would kill our budget

Trying to figure out if I can legally stuff 275/40/17's under all 4 corners with just fender rolling and spacers....

 

fender rolling legal in stock class?