why dont you use a step drill bit or uni bit to drill the hole they work well in thick metal and will last longer. also how much better would it be to do a shelby drop with a negative wedge kit and lowering 1 3/4''

 

if you're extremely careful and have an accurate jig (I made mine on a mill with a DRO), a 1/2" bit will work great. I actually drilled mine with the rear holes at 1/2" and the front holes at 17/32". (Mostly because my drill started to die and caused the driver's side to wander a bit. The passenger's side fit perfectly.) Having both of them at 17/32" leaves 1/16" of horizontal play, which just seems sloppy. It is what they were originally though.

Take your time and use a square to make sure you're drilling straight and it will come out great. There is a lot more metal than you think to drill through - I think it's almost 1/2" thick there. Straightness matters.

 

I used an $8 step drill (that comes in a pack of three) from Harbor Freight. Worked great. The nice thing about step drills is that they tend to be self-centering and they clear the cut metal extremely easily.

 

I used a step bit after I broke 2 other regular bits. I got my step bit from Sears for $20 or so and it goes from 1/8" up to 1/2". It worked awesome! After using the step bit, I used my 17/32" bit to finish the holes off. I highly recommend the step bit or unibit to everyone.

 

any recomendation on this drop w/granada spindles, have an I6 going to 302. Are there spindles that work better than others. Would drop spindles give the same results???

 

The change with Granada spindles would be exactly the same as with Mustang spindles. I prefer to use Mustang spindles, preferably matching the year car in question.

No, even if there were drop spindles, drop spindles would not change the pivot points of the suspension.

 

Yeah, Ford's suspension geometry was all whacked out from the factory. They mounted the upper arm in the wrong location. Works great for a bias ply tire if you want a car that understeers, but I prefer to have a car that actually goes where I point it when I turn the wheel rather than sliding off the road.

 

Funny thing is even with bias tires the "drop" improved handling. It was originally done to match the front end to the prototype IRS Mustang, and Shelby's people saw the car. Turned out most of the handling improvement was due to the alteration of the front, not the rear, so the expensive IRS was dropped. Shelby included the alteration in the 65 GT 350, and it carried over in the leftover 65's used for the first batch of 66 GT 350's. These cars all used bias tires, though. Imagine how easily Ford could have simply moved 4 holes and the cars would have had an even better reputation for handling. I doubt it would have taken a whole day for a machinist to alter the hole location. And remember, this was known before the Mustang even went into production.

 

wasn't the chassis shared with the fairlane? my guess is that the understeer was left in for 2 reasons: 1) safety. "turn harder, let off of gas slowly" is easier for most people than "let off the gas slightly (or add some), steer into the slide, and keep the car balanced." 2) shared tooling with the fairlane. Ford had no way of knowing the mustang would be a runaway success and didn't want to spend another $10-20k (in 60s dollars) redeveloping and testing the front end.

#1 is why all modern cars have understeer from the factory, even the rwd cars.