Quote:
Originally Posted by 67zo6Camaro
Sitting on a beach somewhere feeling bored.... I turn to latG for some entertainment. BAM.... Progress and pictures. 
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I hope you are doing your homework assignment.
Quote:
Originally Posted by Rick D
Very nice Rob, man this Ford is going to be sick
So not push you and I know it's a holiday but can we get some mock up pictures  when you have some time of course!! 
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That's going to have to wait a bit. I have a few other detail surprises coming that I need to finish before you'll see that.
Quote:
Originally Posted by FETorino
Already have em. Michelin Pilot SS 285 35 18 and 345 30 19
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Quote:
Originally Posted by Flash68
He prefers the push of a 275/345 setup....
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Great attention to detail as always DG
Quote:
Originally Posted by Track Junky
I know you went down this road but I have to ask......whats stopping you from putting 315's up front?
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That could start a long topic of discussion in the tire and wheel section, or on this thread. Maybe someone like Ron Sutton will chime in with his thoughts.
First I have limitations to tire size, self imposed limitations because I don't want to do any noticeable modifications to the body of my car.
Starting with that in mind and the black art of tires in general I evaluated the need for steam roller tires in the front. I am by no means an engineer or an expert on this. I have been playing with things that go fast around corners be it Cars, carts or motorcycles for 30+ years so I have some first hand experience and I've done a lot of research on this crap over the years.
First I believe JMO that wider is not the be all end all JMO. I have read and agree that there are benefits to width that go hand in hand with tire height and rim width that dictate the optimum contact patch for a combo. Weight on the tire,more importantly load which is affected by suspension design the cars weight and moment arm all play into it. then you get down to important factors like air pressure adjustment and heat buildup. Just slamming the largest tire you can stuff doesn't guarantee success.
Think of it this way. The contact patch to contact patch is the true track width. If I widen the tires by using more offset I narrow the track width. I also start messing with scrub radius as that patch moves to the inside of the line from the top balljoint through the bottom to the eventual point on the ground.
Im not racing in the Rolex series so no use over-thinking it but I didn't want to go far out on a limb in any one direction.
So I took in some ways a conservative approach and right or wrong a big part started with aesthetics.
I didn't want a 1" or 1.5" outer lip on my front wheel. To me that give a Jiffy POP look of th center popping out of the hoop.

JMO I don't like it.
I also didn't want to be stretching or flaring the front fenders.
This also go me thinking about rim width. Why does one guy run a 275 on a 9" wheel and the Nissan guys run one on an 11"?
From all my reading,
to a point,
not always, wider is better for rim width if it is within the tire manufacturers recommendations.
Look at Porsche they regularly spec tires on Wider than recommended wheel widths from the factory.
My goal was the flattest tread profile for whatever tire size I choose. In reading every .5" of added rim with will add .2" of measured tread width on the same size tire. I looked to match the wheel width and tread with dimension for my chosen tire heights.
I wanted a 26" tall front and 27" tall rear tire to fill my wheel wells and maximize the length of the contact patch and the tires ability to radiate heat.
Out back that was a no brainer. 345 30 19 on a 13" wide wheel. This is the Dodge Viper spec. Michelin built that tire originally for the Dodge Viper. Am I smarter than those companies engineers? No.
So what to match it with up front. Well a front engine rear wheel drive 3400lbs Viper uses a 275/345 combo with a 50/50 weight distribution. I may not get to 50/50 but I'm trying to get as close as possible. I'm also hoping to come in around that weight. Before anyone else says it I know there are more factors than that. To start with CG to Roll center creates a moment arm which actually influences load on the tire as much as total weight. Like I said before I'm not building a Rolex competitive racer so I'll keep it simple.
I borrowed a 275 35 18 mounted on a wheel from Ron, thanks again Ron and a 295 35 18 tire from Brett, thanks bud. the 275 was an easy fit and the 295 ,using my wheel fit tool, was a little big. A 285 should be just right I thought.
Here is where Travis really came through. I had communicated with him a few months ago about a quote for my wheels. I really like the fact his wheels were clean timeless designs and engineered for and used in racing. From my wheelfit measurements I was pretty certain I had a BS measurement and wanted a 10.5" wide wheel wheel.
The 10.5" wheel did two things. The measured tread width of a 285 Mich on a 10" wheel was 10.2" So adding .2" for a .5" increase in wheel width this gave me 10.4" tread width on a 10.5" wheel width. A good match in my mind. It also gave me a 2" outside lip with my backspace measurement to avoid Jiffypop.
In speaking with Travis he said he could build a test wheel to the same specs I thought I needed actually try it on the car. Hell yea. A week alter I had a borrowed wheel made from both new , blem and used parts. Travis sealed it so I could mount and air up my tire.
This was a huge help. I was able to confirm my thinking on backspace, the profile of the 285 on the 10.5 matching that of the rear tire, double checking caliper clearance and getting a real world visual can't be topped.
Tires are disposable items. My car won't be painted before I actually start tuning the set up. I plan on running it in shake down form for a while before I really finish it pretty. If I decide to go wider and do more tweaking on the body it won't be big deal. The 10.5" lets me use a 295 or 305 and still get a good footprint if in the end I feel the 285 is a limiting factor.
I still think the 285 on the 10.5" wheel will give me all the front bite I need if my shocks, springs and bars are tuned correctly.
Gae Last post you accused me of underwhelming you with lack of detail so you are to blame for this one.