Piston Slap: Ponder On Proportions, Please

Sajeev Mehta
by Sajeev Mehta
piston slap ponder on proportions please

TTAC Commentator jrominski writes:

Sajeev, re: New Or Used article a while ago on rust belt engineer relocated to Saltillo with $45k car allowance from first tier supplier employer to drive whatever he wants to drive for work.

Fast forward: 1 year in, he is handing in his employer’s used-up 1 year old V6 cayenne and taking a new GTI with the new engine next weekend. He drives hard, which is OK from destructive testing point of view. He asked for, and receives VW factory 17 wheels, unlike US public. They fit. (Cue old racing adage about brake size and wheel size)

His job prospects include offer to go to Mongolia – new plant there. Who knows what he’d drive there.

Sajeev Answers:

Forget about lusting after diesels, manual transmissions and the station wagons readily available in other countries, I’d kill for realistic wheel options on our US-bound flagship offerings. Mundane cars get it right, but the pavement joint pounding Rolls Royce Phantom’s 21” rolling stock or rubber band tires on a GTI prove that we need more rubber, less rim.

Be it famous racer/tuners like Steve Dinan or any number of grassroots motorsport enthusiasts, we all know the drill: sidewalls are good. They are your friend. It’s important to have enough sidewall for complete tread contact on the road while cornering. If not, the lack of sidewall deflection can lead to the outer edges of tread not making full contact with the road! While “can” is the key word, remember Mr. Dinan cut faster lap times on the base 18” wheels of the new BMW M3 than the street-savvy 19s.

Less technically speaking, proportions exist for a reason: the streets of Paris are just that beautiful because of the ratio of building size to street dimensions. McMansions and other American insults to proportion don’t work everywhere, and the fact that said rust belt engineer gets 17” hoops for his GTI in Mexico means us Yanks need rational wheel choices.

My take? More 16, 17 and 18-inch wheel options, please: depending on an automobile’s performance mission and the sheer amount of braking force (disc and caliper sizes) needed to stop the damn thing.

Think about it and post your thoughts below.

Send your queries to mehta@ttac.com. Spare no details and ask for a speedy resolution if you’re in a hurry.

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2 of 19 comments
  • Mnm4ever Mnm4ever on Feb 01, 2011

    I have a GTI that came with 17" stock rims... I will admit it, I upgraded to 18" rims mostly because they look better. The price difference on the tires was negligable... $15 more per tire. However, you dont notice any difference in the ride. With stock rims and tires, it rode harshly. It still rides harshly, but actually feels a bit better, probably because the Hankooks I bought are just better riding tires than the stock ones were. The GTI has a pretty firm suspension, if you dont like firm suspensions you probably shouldnt be buying the GTI. They make a very nice Golf TDI that looks exactly like the GTI, still has a sport suspension but its softer than mine, and it gets almost double the gas mileage. I see your point for keeping smaller diameter rims on "normal" passenger cars, but for "sporty" cars, who cares?? The BMW 3-series looks like an old man's Buick with the base 16" rims. Even the 17s dont look proportional. The 18s are the sh-t, totally change the look of the car. Chargers with base 18s look like rental junk. With the upgraded 20s... that looks right. Camaros have the same problem. Now Camrys?? Keep the base rims, they look dorky no matter which rim is on it. As they make cars bigger and bigger, then need bigger rims to keep the right proportions. All you guys who are more concerned with how comfy it rides over potholes should stick with Buicks and enjoy the comfort...

  • Obbop Obbop on Feb 01, 2011

    Embracing diversity and multi-culturalism... shouldn't maximizing the coveted "street creds" be at the forefront? An inquisitive Disgruntled Old Coot huddled in his shanty surrounded by howling wind-blown snow close to blizzard-like velocities in what the local weather-guessers proclaim is the most severe winter storm since grandpappy sat out that record-setting affair way back in 1912. Locals advised to hunker down at home, stay off the roads and pray that the electrical grid remains intact. Luckily, in an area known more for ice storms that cover everything with accumulating quantities of ice thus weighing down tree branches, power lines, tops of heads of stationary people, etc. that devastates power grids the current storm, so far, is mainly ample snow driven by wind. Sub-zero ambient temperatures expected this night. Coot Critter quite grateful to not be residing within the back of the pick-up, huddled within the down sleeping bag beneath the thin-skinned camper shell. Envisioning that eventuality I believe that a van should be acquired eventually and semi-converted to an abode that would likely be more shanty-like than a pick-up. Oh. Tires? Is the past-tense of tires "tired"? Or is that merely a one-word declarative question? Other? Oh heck. I choose "C". The answer is almost always "C" unless it is "D". If the answer is "F" that is too many choices and could be a terrorist plot. There is a mouse living somewhere in the shanty walls. I saw him/her/it. Jumped from the exterior ground upwards, several inches, to where the aluminum siding that tornadoes love to rip from shanties and send swirling away at high-velocities and impact humans, cows and other critters; violently lacerating the impacted objects with often death-resulting effects. With its grasping little front paws and little mousy fingernails mouse clutched the exposed (eeeeek!) bit of wood below the siding and hauled itself up. I have not heard or seen the critter so I assume it has settled into the area warmed by the shanty interior heat source but still isolated from my realm/domain/regime. Ample glue traps to corral roaming spiders, bugs, etc. have been mouse-free for two years (brown recluse spiders homeland hereabouts so traps kinda a requirement). Hope mouse appreciates the heat but I will have to take measures to repel the critter when the spring thaw arrives. Oh... tires. Yeah. Bridgestone. The ones that are supposed to provide better-than-average wet pavement traction. With less than 6,000 miles driven yearly the tread it appears the tires may outlive me. Two sandbags in the bed, at the far rear, with two 2x4s placed port-starboard to ensure they remain at the rear, the 150 pounds assist traction when the roads are slick preventing the absolute necessity for snow tires and the associated costs of acquiring/swapping over/etc. said tires. That and being a sensical-for-conditions driver keeps my "dirty side down" and "shiny side up." Yep. Tires. Old fogeys recall "old days" when flats were so much more common than today. And the advent of radial tires and the debates appearing in car magazines, etc. back then. Anybody ever refer to Smokey Yunick or Tom McCahill anymore? Sniff. I'm old.

  • ToolGuy CXXVIII comments?!?
  • ToolGuy I did truck things with my truck this past week, twenty-odd miles from home (farther than usual). Recall that the interior bed space of my (modified) truck is 98" x 74". On the ride home yesterday the bed carried a 20 foot extension ladder (10 feet long, flagged 14 inches past the rear bumper), two other ladders, a smallish air compressor, a largish shop vac, three large bins, some materials, some scrap, and a slew of tool cases/bags. It was pretty full, is what I'm saying.The range of the Cybertruck would have been just fine. Nothing I carried had any substantial weight to it, in truck terms. The frunk would have been extremely useful (lock the tool cases there, out of the way of the Bed Stuff, away from prying eyes and grasping fingers -- you say I can charge my cordless tools there? bonus). Stainless steel plus no paint is a plus.Apparently the Cybertruck bed will be 78" long (but over 96" with the tailgate folded down) and 60-65" wide. And then Tesla promises "100 cubic feet of exterior, lockable storage — including the under-bed, frunk and sail pillars." Underbed storage requires the bed to be clear of other stuff, but bottom line everything would have fit, especially when we consider the second row of seats (tools and some materials out of the weather).Some days I was hauling mostly air on one leg of the trip. There were several store runs involved, some for 8-foot stock. One day I bummed a ride in a Roush Mustang. Three separate times other drivers tried to run into my truck (stainless steel panels, yes please). The fuel savings would be large enough for me to notice and to care.TL;DR: This truck would work for me, as a truck. Sample size = 1.
  • Art Vandelay Dodge should bring this back. They could sell it as the classic classic classic model
  • Surferjoe Still have a 2013 RDX, naturally aspirated V6, just can't get behind a 4 banger turbo.Also gloriously absent, ESS, lane departure warnings, etc.
  • ToolGuy Is it a genuine Top Hand? Oh, I forgot, I don't care. 🙂