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So, I saw the tire commentary in the modifications thread, and I wanted to pose this question in its own. Given the wheel size of the Spyder, what tire dimensions would look proper? This is strictly an aesthetics question and not intended to elicit a debate about the engineering reason for stretching the rear tires. My gut feel was 245/35 and 285/30 since the rear wheels are 0.5" narrower than the GT4. Local tire shop said 285/35 for the rear would be better/preferred given the diameter delta. What is the forum's take? I don't want to overcompensate for stretch by fitting 295/30 GT4 rubber if it results in a mushroom. I'm also willing to forgo the lighter Pirelli N spec for the better Pilot Super Sports, imho.
The catalyst for my question is the gift I received today after 350 miles on the clock. Tire is plugged and will be serviceable for the time being.
Interesting question, I would be curious to find out as well! If we go with 285 section in the back, would that rub the fenders and will that mess up our speedometer?
Doubt rubbing would be a concern. I think it would simply fill out better. Wheel position is quite good, yet folks seem to be contemplating spacers because the tire shoulders are pulled in with the stock tires. Tire Rack specs for the diameter in each PZero size:
OEM 265/35: 27.3"
285/30: 26.7"
285/35: 27.8"
So it would appear the 285/35 has a nominal edge. If my past Boxsters were any indicator, not concerned about speedo accuracy as they were awful out of the box!
I have PSS in 245/35r19 / 295/30r19, but I have 11" rears.
I would definitely not go with a ratio that results in a smaller diameter in the rear than front. The Spyder's PSM is very permissive on Sport Plus and changing the ratio to a smaller diameter in the rear means that the chassis will be less likely to detect wheel spin at the rear.
I would suggest 245/35 / 275/35 if you want to stick with the stock ratios. 285/35r20 won't be too much either.
I would definitely consider swapping out to MPSS as soon as I get mine. I waited on my 991 and wish I hadn't as the MPSS are so much better than the Pirellis.
I haven't looked into it yet, but does MPSS come in our size tire?
I would definitely not go with a ratio that results in a smaller diameter in the rear than front. The Spyder's PSM is very permissive on Sport Plus and changing the ratio to a smaller diameter in the rear means that the chassis will be less likely to detect wheel spin at the rear.
Interesting, thanks for the input.
So the front diameters are as follows:
235/35 OEM: 26.4"
245/35: 26.8"
If I were to change the fronts to 245/35 and the rears to 285/35, they increase in diameter by roughly the same percentage.
Another, cheaper option is to leave the front as-is and address the rears only with wider PZeros.
A Spyder driver from Germany put the same tires as the GT4 on its standard Spyder wheels and it seems worked out very well.
Tire is MPSS and formats are:
- Rear: MPSS 295/30/20
- Front: MPSS 245/35/20
He posted some pics and it works without any spacers, as I understood.
Very helpful, thank you. If wanting wider tires is wrong, I don't want to be right...that looks proper. To my eyes, 285s may still be the secret sauce for the rears....toss up. I will need to meditate on this one or a while.
Never thought I'd say this, but I prefer the stock stretched look on this car. I've never liked it before, but I think it has something to do with this wheel and the styling cues on the back of this car. The stock look just works IMO.
just remember to adjust tire pressures accordingly. the GT4 and Spyder have different tire pressure specs. I expect the Spyder to understeer quite a bit if shod with GT4 tires sizes. the balance on the Spyder seems perfect at this time.
Pirellis are quieter than the MPSS and make the Spyder a bit more fun even if at the loss of ultimate grip.
Really - compared to the Super Sports (not the Cup)? On the 991 the MPSS were (IMHO) a lot quieter, absorbed bumps better and delivered better grip. I'm a fan of them, so curious about folks experience.
05-07-2016, 03:20 PM
Tire Size Options for Spyder
