Is my stock 2.79:1 "conventional" ratio very mild? and if i wanted to take to steps up from that what would that ratio be? and would i feel the change? Also who has the cheapest gear kits?
Well, 2.79 was a common raito used, as it was the standard along with an open differential. The next step up is 3.00 I think, and you probably wouldn't feel a huge difference, if you feel any that is. The cheapest gears are probably going to be richmond gears from summit. 4.30's and 4.11's are going to be the least expensive set as well.
There's a million threads on diff gears on here, perhaps you will get what you're looking for out of those. There is one relatively recent that should give you good info.
It all depends on what you have, what you do, and what you want to do. If you have a non-overdrive transmission, and do a lot of highway driving, and want to keep doing highway driving, pleasantly, then 4.30 gears aren't for you. If you have overdrive and want a high-performance beast that chases other cars around town like a cat after mice, then something big like 4.11 would suit you, and give you lots of power at the tyres. Getting that power to the ground is another matter though. If you don't have a suspension / tyre package to handle mobs of grunt, there is no real point getting big gears. Also, a clapped-out motor won't look kindly on being flogged, so that has to be taken into account. If you have a relatively fresh motor, it isn't an issue.
Route666 hit it right on the head. Can't argue with him. If you want a good all aorund gear set in your rear, then something like 3.50's will give you what you want. Not too many rpms on the highway and still enough to get from red light to redlight in a hurry.
6Stang7 thanks I'm a constant source of wit when I'm in the mood lol.
I would add to the diff equation too, D.Hearne reminded me (remound me?, like rewound, not rewinded, anyways) that classic stangs are relatively light, and you can be a bit more conservative with gears and still get good performance.
Ok one more question ,my 67 coupe is all stock should i get the 3.55 ratio or 3.80 ratio first or upgrade my engine and exhaust first.o yeah my car is a daily driver and in what upgrade well i feel the most change?
If you're using it as a daily driver and do not have overdrive, go with the 3.55 ratio. The 3.80's will be a little hard to live with at highway speeds. My Ranger is just so. I'm running 3.73's with 28 inch tires ( 275/60/15's) and this translates to what you'd have if you went with 3.55's and the Stangs normal 26 inch tires. 75 mph is the upper limit at what I'll let it cruise for any length of time.