Too much wheel/tire?

Cavpilot2k · 04-09-2018, 08:41 AM

SO I know the real answer is that it depends on use, but here is my question:

I have been running stock 261s (18" 7.5, 8.5 staggered) with MPSS 225/40 and 255/35.
I just ordered a new set of 18" Apex EC-7s in staggered configuration (8.5 front, 9.5 rear). Planing to mount MPS4S's in 235/40 and 265/35, because that's Apex's recommended setup.

My use is entirely street, no track (for now). This car is a DD/spirited driving car, though some day may be relegated to track duty when I get a new DD.

Now I am wondering if I am actually going to be hurting my performance by going with the bigger tire setup, because while the wheels shave a small amount of unsprung weight, I'm probably more than making up for it by an increase in rubber weight.

I didn't often spin my 255 MPSS, but it did happen occasionally and I am going to be adding more power, hence my rationale for wider/more grip.

I am just questioning my decision, wondering if I overshot the sweet spot between grip and unsprung weight.

Thoughts?

Eyeman · 04-10-2018, 05:24 PM

A good way to me of viewing what to do to improve our cars is to look at what they did to the 1M. It's generally viewed as one of the coolest cars out there, and it has substantially wider rubber than the 135. I think you'll notice the improved traction much more than you'll notice the a couple of extra pounds of unsprung weight.

04-09-2018, 08:41 AM	#1
Cavpilot2k Chief Warrant Officer 1023 Rep 1,638 Posts Drives: like a damn lunatic Join Date: Feb 2012 Location: Boston iTrader: (0)	Too much wheel/tire? SO I know the real answer is that it depends on use, but here is my question: I have been running stock 261s (18" 7.5, 8.5 staggered) with MPSS 225/40 and 255/35. I just ordered a new set of 18" Apex EC-7s in staggered configuration (8.5 front, 9.5 rear). Planing to mount MPS4S's in 235/40 and 265/35, because that's Apex's recommended setup. My use is entirely street, no track (for now). This car is a DD/spirited driving car, though some day may be relegated to track duty when I get a new DD. Now I am wondering if I am actually going to be hurting my performance by going with the bigger tire setup, because while the wheels shave a small amount of unsprung weight, I'm probably more than making up for it by an increase in rubber weight. I didn't often spin my 255 MPSS, but it did happen occasionally and I am going to be adding more power, hence my rationale for wider/more grip. I am just questioning my decision, wondering if I overshot the sweet spot between grip and unsprung weight. Thoughts? __________________ "Prius" is Latin for Eunuch. "Hrothgar": 2012 135i: 6MT M-Sport, BSM/Blk; Nav, Premium, Convenience, HK Dinan Stage 2 +PPK /// BMW PE /// VRSF CP /// K&N /// Koni Sports /// RSFB Inserts /// MPS4S 225/255 /// Other Stuff
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04-10-2018, 05:24 PM	#2
Eyeman Colonel 121 Rep 2,037 Posts Drives: 2008 135 blk, blk, step Join Date: Jan 2009 Location: Atlanta, GA iTrader: (0) Garage List 1994 Porsche 968 Cab [0.00] 2017 AMG GTS [0.00] 1994 Porsche 968 Coupe [0.00] 1977 Mercedes 450SE ... [0.00] 2008 135 [8.00]	A good way to me of viewing what to do to improve our cars is to look at what they did to the 1M. It's generally viewed as one of the coolest cars out there, and it has substantially wider rubber than the 135. I think you'll notice the improved traction much more than you'll notice the a couple of extra pounds of unsprung weight. __________________ Injen, RR OCC, MadDad Whisper, donut spare, 19x8.5et43fr 19x9.5et45r Volk LE37's, rear fenders rolled/pulled, PSS4S 225/35fr 255/30r, KW V1's, AR coated catless dps, Cross strutbar, CF grills and license plate holder, iCarbon diffuser, ETS black anodized FMIC, M3 control arms, Quaife, ER chargepipe, ForgeDV's, Topspeed Custom Tune, V3sims, Braille, Andrey_GTA rear hub mod, Ebay Mstyle front bumper and performance style side skirts.
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