quote:

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Originally posted by darnoldrs

If you were talking steel on steel like a train, then i would agree, weight/surface area = grip or friction.

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What the physics says is that surface area doesn't come into it. "weight/surface area = grip or friction." I didn't say that, its wrong, so you cant agree with me on that.

"...as a tire gets wider its compound can be softer with out the issues with over stressing the tread(once again the load is spread over more points)"

That i will agree with you on. Which is why i believe a wider tyre is getting more grip. Also with the finger vs hand thats different to a tyre because we are looking at rotational friction not kinetic friction.

Im betting this could go on for awhile, because I'm stubborn and I'll stand by the science till i can be proved otherwise lol. Would be stupid to pay $25,000 to learn science if i didn't agree with it lol. So i think like religion vs science we will have to agree to disagree.


But disregarding size. BFG's should be stayed away from. And Avengers are good/better than expected.

Thanks guys, next time i'll try to not post such a controversial topic =P
Jordan

Yeah good luck with 275 tyre.. pmsl I hope you get your brakes sorted ..post pics when fitted for a good laugh[(#)]

Go have a laugh at Phil's Cortina its got 285's on it.

::EDIT::
I just thought i would mention that i like Phil's Cortina its one mean beast. And before you start saying that he has them cause he needs them and he has the breaks to stop them ectect. thats all well and good but Im still going to have an engine that can turn them, might not be as powerful but it can still turn a wheel. And I will still have breaks that are better than the std drums. They might not stop it as quick as phil's huge breaks but for the road it will stop. Not like i'll be going much quicker than 110.

p.s I didn't think laughing at each others cars was in the spirit of this forum.

p.s I didn't think laughing at each others cars was in the spirit of this forum.

I thought so to[V] its your car man do what you want and enjoy it.

quote:

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Originally posted by JordyCharlieBoz
p.s I didn't think laughing at each others cars was in the spirit of this forum.

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its not so much laughing at your car, its at your approach to the tyres u want to run, working out co-efficient of friction and that stuff. your comment about surface area not having muh influence is plain wrong. more surface on the road = more effort to spin it. plain and simple. standard escort came out with 155 tyres. let's say it has a contact patch with the road of 155mm x 400mm, which equals 62 000mm2 . your 275 tyres, with the same contact patch, equals 275mm x 400mm, which equals 110 000mm2 . just short of double the contact patch.

theory is all well and good, but there is a reason that they wind tunnel test new F1 bodies and new cars, theory is not always correct, thats why its called theory.

I think you are going to struggle to fit 275s under there. You said you have cut some metal out, but unless it's a fair wack, you will need to have the car sittng very high with stiff suspension or it is going to rub, badly. Yes you just 'might' fit the width of tyre under there, but any suspension travel is going to cause issues.

In order for Phil to get his 285's under there, he was firstly using a cortina, gigger tubs standard, however he then needed to mini tub, remove metal, and pump the guards, even then its a tight fit.

My advice, grab on old tyre of the size you want,fit it up to a rim and have a tril fitment before outlaying any cash. From experience, measurements are all good and well, but until you actually get something in there, its all theory...
Shaun

Guys, we really should be a little more supportive[;^)] We wouldn't see any fresh unique cars out there if every new build idea was bagged before it got off the ground...some factual feedback is a good thing but having a laugh at another's expense is disappointing not only to the targeted person

As far as wider tyres go...wider definately does not always increase traction...the increased contact patch works against traction as the downward pressure per square inch is reduced...reducing traction per square inch if the coefficient of friction between the tyre and road surface is not sufficient. This can easily be seen when a wide tyre on a wet road looses traction far easier than a narrow tyre. To counter this issue you need to increase the downward force or weight over the tyre, you can ad weight to the car...which defeats the purpose or with some very clever suspension geometry you can increase the downward pressure using the laws of physics. There is a theory in car suspension called anti squat theory...this theory involves the car being lifted by the suspension of the driving wheels at the latitudinal,longitudinal and vertical centre of gravity of the car. If you can achieve this, you have 100% of the weight of the car over the driving wheels instead of maybe 40% in a rwd car. If anyone has seen the RRS Mustang rear suspension set up with what looks like a single ladder bar running forward to around the gearbox from the diff? This set up is partially utilising anti squat theory. To fully utilise and tune anti squat theory you need 4 link rear suspension, the bars must run forward in pairs and the centre lines of the bars on each side must be parallel with the centre line of the car. With corner scales,2 1 foot high blocks and trigenometry you can determine the longitudinal and vertical centre of gravity...usually in the front drivers and passengers space about 10 inches above the floor. With 2 imaginary lines runing forward along the centre line of the bars, the lower bars slope up towards the point where the vertical and longitudinal centre of gravity intersect. The upper bars typically will be level or sloping down very slightly to have the invisible line through the centre of the bar intersect at the same c.o.g. point as the lower bar. Do this on both sides. This setup will cause a torque reaction in the rear suspension that will cause the car to be lifted at the centre of gravity and transfer 100% of its weight over the rear tyres under a hard launch(aka drag racing). You can see this theory at play in cars that dont wheel stand but seem to lift up level and shoot forward when launching. Infact a wheel standing car is poorly setup. Antisquat can be de tuned slightly and used in circuit racing and on the road...it works very nicely as this is the theory I used to design my rear suspension and have used it sucessfully in drag,circuit and street driving.

At the end of the day wider tyres look tough in the right environment...you can fit them to anything...limited only by your imagination/ability and local road/vehicle laws[;^)] Its a good start to understand the theorys involved before making any decisions

Please be nice to each other

You should be able to fit 235's with roling the rear guards, not sure how low youcould go thou.
If you mini tub the rear you should be able to fit 245. Much wider than that and you need to full tub a mk2 escort.
With a full tub then you can go back to the chassis rails. I have a 285 tire that i dont think will quite fit, even with a full tub right back to the chassis rails.
I agree with escortinadriver. Get an old tire of the desired width and as close to the corect height as possable and fit it up under the guard and see how you go.
Personaly i would be sticking to 235's (if they dont scrub). Even that is a wide tire on an escort[%].
As another point of interest, 275-60-15s will be a very tall tire. to big in diamiter for an escort. You would need something more like a 275-40-15 (at a guess) to be the right rolling diameter.

Yeah i was concerned about the height of a 275 60. Antique tyres can get Avengers in 265 50 which is a discontinued size which is much shorter. On Tuesday i will be trying to find a tyre to put into the arch and see if it will fit. I will put my single leaves in while im at it so its at its aprox ride hight.

I have removed a LOT of the std wheel tub thing. Like you look into my boot and there is a gaping whole in the side of the car. I did that so that i can take full advantage of the extra room the flare gives. The wheels are being pushed as far into the flare as they can with the diff being cut to length so that gives me extra width.

So yeah i hope to update this on Wednesday or Thursday with "I can make them fit =)" on the other hand it might not work out then ya'll can say you told me so =P

Good luck on the trial fitment,

Be sure to take some picss.. There's soething about a guard with maximum tyre crammed in there.... If only we had as much room as an XA/XB....

Shaun