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If anyone remembers. The 393 I built had a valvetrain tick that I could not figure out. Anyway, I took it to a shop where they measured the rocker lift throughout the valve train and came up with a flat cam lobe. So alittle over a month goes by and I pick the car up yesterday. Drive it off the trailer and figure lets just drive it up and down the street.

Wow, this engine screams. It breaks traction in 1st, 2nd, and 3rd gear from a slow roll, I haven't made it to 4th or 5th gear yet. The gearing seams to be very low. I don't know if the rear end has ever been changed or not. This car only has about 70k miles on it and has sat for at least the last 10 or so years,it is supposed to have 3.00 open gears, however both tires spin when it breaks loose.

Now what do I do about the lack of traction.

Should I replace the 185x14 tires with something larger. The guy at the shop say's that I need a drag radial back there. I told him I had just bought 15x8 magnums and plan on running 245x15's he thinks I need to go bigger yet.


Any ideas on what I should use before I by the wrong tires. This will be a street car, not a race car.
 

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White Elephant Guy
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I think you'll be fine with the 245/15's any bigger than that and you'll have issues with them either not fitting or sticking out beyond the wheel opening.
 

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Bigger doesn't necessarily mean more traction. Adding a set of CalTracs will help tremendously. The only way to get maximum traction is with a set of tires that are up to the job, like drag radials or street slicks (ET Streets, Hossier QT Pro's, etc) and proper chassis tuning.
 

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Well, I've seen a device on ebay sell that goes under your gas pedal to prevent excessive acceleration!!! Looks pretty easy to make to. All you need is a 2X4 piece of wood :joker:
 

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I think you'll be fine with the 245/15's any bigger than that and you'll have issues with them either not fitting or sticking out beyond the wheel opening.

BZZZZZZT!!!!


295's will fit perfectly in the back.
 

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I thought I heard some screaching outside recently...was that you? :lol:

If you listen, you'll probably hear me...just point your good ear toward west Corona.

But really, 245s ain't gonna do it...go bigger if you can. At least in my case since I converted to a T5z 245s are a joke in 1st and partly thru 2nd up to 50 mph or so and i've just got a lowly 331. Maybe it's my tires...don't know but they seemed to be good ones when I bought them...Falken 451s.

Can I come see your new tire frying toy?
 

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Discussion Starter #8
Tracy, been kinda looking forward to meeting you in person one of these days. Is the Irvine thing still on. Let me know when you can stop by. I have the car now, I am trying to finish it up and get it back to my dad in the next month or so. Any input you can shed would help. I am just off 15 fwy between 6th street and Limonite.

Bob

295's will fit, would that be a 50 or 60 series tire. Will it fit with out rubbing?
 

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If you must keep the 14 inch wheels, be careful with adding to much meat at the rear, as the handling may suffer due to
too much sidewall lateral shift during the cornering process.

A way to mitigate this is to upsize in wheel diameter size and width (folks here usually and wisely increase only the
backspacing) to help balance the tire width and sidewall increase.

I believe that there is that famous tire and wheel chart here on the VMF....
 

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Gone but never forgetten
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My guess is you need to a) get rid of the open rear b) get better traction tires c) get much bigger tires and d) upgrade your suspension.

When I first fired up my 408, I had a 2.80 open rear and the most shot rear leaf springs you can imagine. Even with the 275/50/15's T/A's in the back, I had to feather the clutch to leave a stop light without tire spin. Since then, I've upgraded the rear to a 3.50 traction-lok, and the rear springs to a 5 leaf grab-a-tracks.

I'm still just trying to pile some mileage on my clutch (inaccurate odometer now says just over 500 miles on the engine/tranny/clutch) so have only opened the secondaries once, but I can leave the line now quickly without all the tire spin.
 

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Make sure that you get some good tires. The problem is that most of the state-of-the-art tires don't come in 15" sizes. The ubiquitous BFG Radial T/A tires are pretty hard and don't have much traction.

In a 15" tire you pretty much are going to have to step up to drag radials to get traction.

Me, I'm going to upgrade to a 16" Magnum 500s and run Goodyear GS-D3 tires.

I also agree with the Cal-Tracs. They (Calvert racing) also sell their own "mono" leaf spring designed to be used with the Caltracs. A guy on the FE forum is running 10.60 quarter miles in a 69 Mach with Caltrac springs and traction devices and Goodrich drag radials (15"). Of course he has a 511" FE motor, but still. The car is very streetable.
 

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This question is for Mike Czap and your beautiful yellow Mach 1. Mike, what is the color code of your Mustang. I love the pictures. Email me back if you would. Thanks - Mark
 

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good tires and whatever you can to get weight shifted to the back end at launch. This includes adjustable shocks that allow you to set the rate at which the front end can lift. Staggered shocks in the rear can help dampen axle windup and keep the rear planted. Move the battery to the trunk and use a full sized spare in the trunk. Hey, keeping a hydraulic jack or toolbox in the trunk would help too :joker: traction bars, rear sway bar (sized less diameter than the front sway bar), and stiffer rear springs would help. sounds like you are going to have fun with that ride!
 
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