JasperGT

What problems are you talking about?

howarmat

all that tells me is you have lots of money and cant make up your mind.

You made the statement

I am sure you have "technical" data of all the people that have crashed on the various mustang forums and know exactly what tire size they all were running.

Any more BS you would like to make up to "sound" smart

VistaStangGT

You know what, he's right, his dad has a helmet, he has to be right. Of course my neighbor who rides a short bus has one too and his is painted pretty colors so maybe I should ask him his opinion on tire sizes.

Legion5

The only reason I'm responding is because you're howarmat.

the goodyear tires i got free with a sponsorship. Plus remember I have 2 cars that both need tires, and I resold almost all the tires I didn't like on ebay after with usually 90% thread left.. I recently resold the Bridgestone Protenza 50A's like 2 weeks ago and made 78% of what I paid back after running them down 15%.


Umm I recently pointed to the guy running 255/275 and said "That's not the tire size I was reffering to" that doesn't sound like I'm making stuff up. I know at least 3 people on the forum here that have crashed in the rain running 245/255-20 front with 295/305-20 back and i only know one that wasn't. I've also tested out both 245 and 285 and 275 for a front tire with 20's and you can easily feel why the performance changes which lead to those situations arise with back to back testing in the rain.

Besides that before the mustang I used to drive my EVO in rally. Rally racing is the ultimate test of tires designed for the common street and the horsepower is easily comparable.

I know my tires and I'm always trying to learn more about them. You seem to know next to nothing about them and you've shown nothing to demonstrate knowledge.

Even Carrol Shelby agrees with me, the 725 hp super snake which was built at my shop 4 months ago had 255/35-20 front and 275/35/20 rear tires, you're telling me that I'm full of **** when even Caroll Shelby won't put 245 295 tires on a 725 hp car?

You sound exactly like the guys running the rally teams that consistently lost. I've said that to dozens of people in real life and I'm not just singling you out.

Norm Peterson

Legion - it's a little like pulling teeth . . . I'm too tired (after shoveling snow and slush twice today) to go through my FSM to verify your separation of speedometer and odometer functions, but unless you have set up your car with a nondriven wheel odometer for Equipped class TSD rallying I don't believe it. ABS is a different story and while I suppose that you could integrate the front wheel speed signals and come up with a distance travelled I don't think that's how the odometer is being driven. Maybe I'm wrong, but I'll need some harder evidence than an offhand remark.

I wasn't intending to start a credentials battle, just looking for some insight about where you're coming from. Anyhoo, let's just say that I have ~3/4 of a lifetime taking an engineering approach to understanding most everything automotive and nearly 40 years job experience in various engineering capacities. Some autocrossing and TSD rallying (which isn't always as "tame" as you might think).

Before that incident can be considered fully applicable to the OP in this thread, please provide more information about the car and the driving at the time.


How so? People do all kinds of mods to their cars that don't necessarily make logical sense to somebody else who uses their car(s) differently. While it's perfectly OK to chime in with a dissenting viewpoint, it's not reasonable to expect that opinion to be welcomed with open arms if there's no presentation of your thought process. Remember, you're mostly trying to change peoples' minds, and that requires more than vague hints.


I'll stipulate to the tire makes/models as being mostly irrelevant here. But from what I see above, it is quite possible that one or more of your own front/rear combinations was nearly as far skewed from the OE fitments as the combinations that others have mentioned (the 305/245 was your mention, no?). Can you line the tire and wheel sizes up so that meaningful comparisons can be drawn? Front tire & wheel size, rear tire & wheel size.




Norm

clentonz

Well, to the OP I hope that us......"amateur car enthusiasts".......have answered your question. Imo, I would run 245-35's in the front and 295-30's in the rear....should not give you any problems driving, and will look badazz! Do you have an idea on what wheels you are going to get? Sweet looking car bro!



"FYI the tire choice you mentioned is the one that's seen by far the most tire related crashes on the S197 mustang's various forums."

Where is the proof on this?^^......And no, knowing more people who have crashed with a particular size, than people who have not; is not proof.....imo....

I mean.....for example.....What if someone does not get these "wider" tires b/c you said this about them, and they end up getting in a crash b/c they didn't have enough traction or rubber in the front (or back)?.....IMO.....Just doesn't sound right to me, for saying something like that without proof


Sorry, I'm not trying to sound like a a** or anything like that(sorry if you take it that way, b/c I really don't mean too).

Red Beast

yea, thanks for ur help guys. i think i will go with 245/35 front and 295/30 in the rear, ive already hydroplaned my car already into a curb and broke my axle before, so ive already learned my lesson, trial and error, i havent ever driven my stang wrecklessley since. and to answer ur question, i was thinkin about bullitt motorsport wheels, i would get foose nitrous wheels but i cant afford that, but... i did meet chip foose a week ago, and supposedley he comes into my work all the time, just during the morn, and i work nights, so if i c him again im gunna try to make freinds with him and see if i could strike a deal with him... u never know he was a really chill dude.

Legion5

sure... I'm not sure why you're assuring the OP that he won't have any problems whatsoever with 245/295..., I don't even run anything close to that without severely altering my rake to compensate with the suspension because my car doesn't overstreer right if I don't. Also there's no way to crash because your rear tires are too narrow, it's actually the opposite lol. A car on a street has problems when they run into uneven dirty or wet surfaces and the car becomes unbalanced front to rear. With a narrow tire the rear end will be putting down a higher pressure per square inch (psi) than a wide tire because the weight will be spread across less rubber.

By having a narrower tire putting down a higher PSI this has the effect of pushing down harder against the street dirt and compacting it more (which acts like ball bearings to cause a crash when loose) or it has the effect of diverting water. Narrower tires compress the material under them giving you more traction when you need it. This is the primary reason why in certain rally situations it's best to run 175mm snow tires in the hot summer and you end up being significantly faster in a 2500lb 300 horsepower car on a very dirty street road. A Subaru WRC is as fast as the fastest mustangs or pretty much any car out there and their team runs 205 tires that look like this, and check out where it's driving too, it's where you drive with a car usually weighing 3500 lbs. Subaru goes 0-60 in 3.4 seconds.



The different ways wide and narrow tires react and interact and the ways different tire profiles change handeling especially when staggered are a primary principle of setting up a car to rally on a street, these factors key ideas, and very important to the handeling results you see as well as safety.

Picking a tire based on equivalent sizing and the fact everyone wants a 295 tire for a 300 hp car highly conflicts with maintaining the above and preforming best. If you remember anything take that away. Also the simple way of picking tires doesn't even make your 300 hp car faster in a straight line, but instead with 300 hp it will be slower due to rolling resistance and weight (that's a long topic in itself).

I've also confirmed with Roush and Steeda that they do not use deeply staggered tires on their vehicles with 20" wheels on the Roush RTC and Steeda GT500. Also I've confirmed with the Ultimate Bad Boy mustang team which makes the most powerful mustang money can buy featuring a 1000 horsepower Ford GT Supercar engine that they use 275 & 305 tires. This is a car that beats a Buggati Veyron half way to 200 mph and stays not incredibly far behind after that. They could easily have put a 335 tire on their awesome machine at the same diameter and even though they are running only 305's they modify the rake to compensate the weight transfer using a tuned set of coil overs.

You're telling me, your 300 hp stock car needs a 295 tire, a much thinner front tire, than a UBB Roush Saleen Shelby or Steeda mustang, and no suspension adjustment?



Anyway also obviously based on what I said originally it just "seems" that 245 with 295 tires cause crashes, it's not a fact because not everyone has been surveyed but wouldn't you think it's a good idea to avoid something that seems to destroy cars? It's way way way cooler to just plunge in and do dangerous stuff but besides that benefit there's other stuff going on (sarcasm).

jdmcbride

It doesn't sound like the OP is putting this combination on his car for performance reasons (hense the 20" wheels), he is going after the staggared look that so many on this forum like. That is his choice. Yes, he should know that a staggered setup will create more understeer and could cause the car to slide out of control sooner than a car with equal size wheels and tires at all corners. But he never stated how he was going to use his car (1/4 mile, autox, etc...), so I assumed he was going after looks, not performance. JMO.

Norm Peterson

I doubt that very many people buy tires with the same outlook as do the pro rallye outfits. I know that I never have, though I haven't had reason to shop in the 295-up category either.

From performance considerations, the dragstrip and NASCAR/road course/autocross influences are more well-known and therefore greater. In each of those, the end(s) that need more grip tend to get wider rubber, rules permitting. On the street where appearance takes on somewhat greater importance relative to performance to many, I don't think there are any rules (with the possible exception of a 60% width rule that I think California has or at least had at one point).

I'm not saying that to choose tires based only on performance on other than relatively clean pavement is wrong. Yes, tire buyers should consider the full variety of conditions they experience. But to insist that there is only one weighting of the variables that everybody must adhere to is somewhat narrow-minded.

I'd still like to know what else was involved in those accidents. A 245-width tire is more than sufficiently capable at getting the car turned during anything resembling reasonable speed for conditions, pretty much regardless of what the rear tire size is. It may understeer like a pig, but it will turn. If the problem is the 295 rears coming unstuck, larger front tire sections (for less front:rear stagger) won't fix that, so stagger, per se, isn't the problem. About here is where driver error comes in. Maybe it's that 295's on these cars are more sensitive to driver input, maybe those who have chosen 295's have not developed the necessary level of throttle modulation or other vehicle control skills, or maybe there was a locker or a spool in the pumpkin as well; we just don't have enough hard evidence here (yet).

There is a stretch of road on my way to work that S-curves rather nicely that is partly but not yet completely down to bare pavement since the recent snowfall (mostly light here). Long story short, driving through it this morning I could get either or both ends of the car to lose grip at will, and you become acutely aware of things like curbs when that happens. Does that mean that having OE 235/50-18 KDWS's all around is something that should be avoided (or should not have even been specified by Ford) simply because there is at least one very predictable situation where loss of control with those sizes is so easily possible?

This whole single cause of consequences thinking reminds me of an incident back in my early college days - true story - when a classmate of mine wrote a little Fortran program (on punch cards!) that determined vehicle "safety" based solely on its weight distribution.


Norm