Performance tire upgrades?

[mason]

Ok, let’s talk aftermarket tires. Not for the “bling” factor but tires to improve the cars performance.

Now I think some of you will say that Lotus designed the car to be fitted with this wheel and tire combination and we should leave it alone… Well, yes and no. Lotus designed one of the best handling cars available but like all other car companies Lotus also designed it for the average driver and in doing so set-up the car to under-steer at the limit. The reason being is that it’s much easier for the “average” driver to recover from under-steer than from snap-spin resulting in throttle lift over-steer.

For those of us looking to use their car on the track or at an autocross, this “built in” under-steer can really make the car difficult to go at 10 / 10ths. Also because the stock tires are designed to last a few thousand miles their performance won’t be as great as a set of R compound tires.

So given all of this what are our options for “upgrading” the tires on the Elise. Unfortunately because the car comes with a very odd size from the factory our choices will be limited.

Stock Sizes: Front 175 / 55 /16 and Rear 225 / 45 / 17

A quick search of the Tire Rack website reveals that there are no tires available in the front stock size and but quite a few performance “street” tires available for the rear (BFG K/D, Bridgestone S-03, Goodyear Eagle F-1, Kumho Ecsta MX, Michelin Pilot) but nothing in R compound.

So what are our options?

If we plus size the fronts we can get the following sizes while maintaining close to the same rolling diameter.
185/50/16(1.3% smaller) – No tires available
195/50/16(0.4% larger) - Some tires, but no R compound or true performance
195/45/16(2.8% smaller) – Pirelli P Zero A, no R compound
195/40/16(6.1% smaller) – No tires available
205/55/16(5.5% taller) – Performance – BFG K/D, Bridge. S-03 and S-02, Falken Azenis no R compound
205/50/16(2.1% taller) - Bridge. S-03, GY Eagle F-1, Michelin Pilot, Pirelli P Zero, no R compound
205/45/16(1.3% smaller) - GY Eagle F-1, Pirelli P Zero, Yoko Parada, Kumho E700 R compound
205/40/16(4.8% smaller) - Yoko Parada, no R compound
215/50/16(3.8% taller) – No tires avalible
215/45/16(0.2% taller) - Michelin Pilot, Falken Azenis, no R compound
215/40/16(3.4% smaller) - GY Eagle F-1, Pirelli P Zero, Hoosier ASO3 R compound

So for the weekend warrior is would seem that the choices are very limited, with any tire smaller than a 205 probably not giving very much of a performance advantage. The smallest 16” R compound tire being a 205 and the “mack daddy of stick” Hoosier in a tall 215.

Well I wonder how much fender Lotus gave us to play with up front?

[bob]

What about different sets of wheels? Surely there must be something available in the same bolt pattern/offset that would provide more tire choices...

What would the classing implications be? Know of any other cars have different sized wheels front and rear?

[bob]

Also - wouldn't a stiffer rear sway bar solve much of the understeer issue?

[mason]

Originally posted by bob
What about different sets of wheels? Surely there must be something available in the same bolt pattern/offset that would provide more tire choices...

Well, yes there will be options of different wheels to choose from but the advantage there will probably come from weight savings. I'm going to assume here that a 16" wheel is the smallest that will fit over the brakes. If so the basic problem is the very limited tires that are avaliable is such a realitively narow width for a 16" (and larger) wheel.

Originally posted by bob
What would the classing implications be? Know of any other cars have different sized wheels front and rear?

As far as classing goes... that depends on what kind of racing you're dooing. SCCA SoloII for example has very strict limitations for running stock class, which include running stock sized wheels.

[Tripledigits]

Mason

I've been hearing that a 205 may not fit on the front, clearance-wise. If it does fit, I've heard it will probably require the sport suspension upgrade for clearance. It looks like a tire company will have to come up with something for us, unless Lotus solves the problem for us.

Jeff

[Ridgeman580]

Is the difference between '16X5-1/2' and
'16X6-1/2' only the width of the tread that touches the road? Also, are only
the '16X6-1/2's' forged?

[mason]

Little update:

In the
205/50/16(2.1% taller) there is Hoosier avalible in the Roadrace compound (good for track and lap days but not as good for Autocrossing)

The better news is in the new Hoosier A3SO4 (and R3SO4 roadrace) compound there is a:

205/45/16 (1.3% smaller) avalible


Perhaps still a little too wide but at least being a little shorter may help out with clearance (like the Kumho).

[fitfan]

I have been thinking over the LSS deal.. and might opt to NOT get it - this is the reason...

You really need to sets of wheels to track and street your car - since i don't have a handy tire changer in the garage... a track set on an aftermarket wheel makes good sense for me. Then i can up the other suspension components as time goes on bit by bit - for the 2-1/2 grand for the LSS option, i feel i can invest that over time, and have a set of real street tires and real track tires on a lighter wheel.

so after about a year i plan to get a lightweight aftermarket wheel and track tire combo...

[rnorwood01]

Mason -

Can you post your original on this thread on SELOC? I'm interested to see the European view on what you said.

-Rob.

[rnorwood01]

By the way, they think that anything bigger than a 195 will rub on the front, but they do acknowledge that taking it up a size will cut down on understeer.

http://forums.seloc.org/viewthread.php?tid=10644 (if you have access).

[mason]

Rob,

Feel free to cut and paste what you'd like to the thread in SELOC. I don't want to do it myself as the tread looks a little old and I sont want the SELOC members to think I'm spamming their site.

Mason

Originally posted by rnorwood01
Mason -

Can you post your original on this thread on SELOC? I'm interested to see the European view on what you said.

-Rob.

[Tripledigits]

Originally posted by bob
Also - wouldn't a stiffer rear sway bar solve much of the understeer issue?

The Elise is setup with no rear bar.

[edgar]

In our HK experience there is only very few choices in rims for the S2.

Lotus factory has a set of rims specifically for 195/50 fronts and 115/45 rears and only one tyre choice Yokohama 048LTs which is a cross between M and S compound.

KMS in Japan makes a very nice and light set of wheels in 16/17 combo

and even more ideal in 15/16" combo which will allow you a wider choice of really sticky rubbers.

Wedsport in Japan also makes a set of rims for the Elise but for S1 only.

[mslpilot]

With questions of best all out performance......... Autocross, proSolo and such. Why are we talking about stock set-up? Anyone getting this serious about being five miles from an event will do aftermarket, high-dollar suspension or at very least the LSS? Right? I'm more interested in a cool set of rims, Lotus or not to put on her on non track/commuting runs. I want some high grip, as high mileage as possible recommendations, and some rims to put them on. Don't want to drop the front diameter either from the LSS. Keep the understeer gremlins away on day to day. Figure I'll just ground ship my LSS wheels and AO48's to the track/event. Drive the Elise, pack a lug socket and voila'?? Hope somebody has a jack?

PS how do you raise this lil' minx? Do you have to take the underpinning off to change the tires?

[ulmpharmd]

What are you guys (like myself) that live hours away from your nearest dealer going to do about tires as far as blow outs and such. I might go ahead and keep one handy if i can only get the stock size through the dealer.