What gears to use?

[Snake]

Hey Everyone! What is the best setup for rear end gears? I will be driving it to work...but would like to smoke the tires once in a why'll. Using a posi setup and a 302 H.O.
Thanks.
Gerry.

[Dwight]

I have a 5.0 in my LS and I'm running 3.55 gears. Good on the hiway and still have a lot for the vettes at the lights. 3.73 will give you more at street light but you'll turn more rpm at the same speed on the hiway. Do the the math and pick one. Both will do you right.

[ERA535]

If you are running a 302 and want to smoke the tires you not only need 5.36 gears but you must make sure to put 175 X15 tires on the back. And make sure you inflate them to about 35 psi.

[Double Venom]

ERA:

Shame Shame !

Anywhere from 3.27:1 to 3.73:1 will work just great.

Mostly cruisin' and still smoke em easy 3.27's,
Run the dracgs...with a 27/28 inch tall tire, slam those 3.73's
All around zippidy do da... 3.55's

ERA shame, shame!
DV

300 Cobras is NOT enough!

[klayfish]

My 302 H.O. w/T-5 trans has 2.73s in it. I can definitely say they are too high. I think I'm going to change to 3.55, possibly 3.73, for better acceleration and autocross.

Check out this website. It's great. [url]www.smokemup.com

You can calculate the speeds at each rpm using different rear ends.

Steve

[blykins]

Also depends on what kind of tranny you're using...my Dad's 97 Cobra has a new T-45 (had to replace the Borg Warner unit that came with the car). It's geared 3.35 on 1st gear, but it's also got a .67 overdrive. When he bought the car in 1997, he immediately changed the cogs from 3.27 to 4.11. Talk about turning the heat up on a DOHC motor. It's a good thing he's got the rev limiter bumped up to 8k...you can hit it quick. Anyway I'll quit rambling and get back to my point. Even with the low rearend gears, the tranny still lets him cruise 70 mph at around 2700-2800 rpm if I remember correctly. We were playing with a 911 Porsche on the interstate. We were running 140 and it was taching 4500 in 5th.

So basically, it depends on the tranny too on what you can get away with.

[Snake]

Thanks Guy's for your quick reply's.
I guess I'll have to flip a coin between 3.55 and 3.73...Hmmmm?
175 X 15 on the rear....ya right!!
Gerry.

[CobraEd]

Gerry,

I have a carbed 302, aluminum heads cam etc etc, and I can burn the tires at will at any speed in first gear without ever touching the clutch with my posi 3.73s. These gears give good torque multiplication across the board. If you are concerned about highway cruise rpm, go with the Ford Motorsport Superduty T5Z fivespeed. It has the highest overdrive of any transmission that I am aware of at .63. With 3.73s and a T5Z, you will get the best of both worlds, great power and low highway cruise rpm.

If you already have a regular T5, the T5Z will just "pop" right in.

Ed

[Snake]

Got a carb set up too...and the T5 trans....Yep! 3.73 gears looks good right now for me.
Thanks.
Gerry.

[ERA535]

Snake -

You're a good sport!

How "built" is your 302 and what size and kind of tires are you running?

In the long run I would go for the ability to drive the car without getting beat up by a bunch of revs....

.....I am sure that with almost any gear and a decent clutch you could smoke them whenever you wanted to, therefore I would go for a gear that you can live with.

I would lean toward the 3.27's.

Does your wife or significant other ride with you much?

Good luck with your choice.

[renaissance man]

I'm running a 289HiPo with a 4-Speed Toploader and a 4.10 rear end. I'm going to switch to 3.50-3.55 (whatever it takes) which should bring down my rpms from 3700 at 70mph to about 3200 or so.... Don't need no stinking overdrive. 1:1 ratio is a blast!

[JoeLafives]

CobraEd:
Can the T5Z work on an older engine. I've read that it only fits 79-93 years. It that correct?

Scott

[CobraEd]

No problem, it fits all 289s 302s and 351Ws (and many other engines too). What you read is that it is a direct "bolt in" replacement for the newer engines with no other changes, but it will fit the older ones too. My engine is a 72 block. Just get the right bellhousing to go with it. By the way, the T5Z is also the strongest of all the T5s with special moly gears and other good stuff for additional strength. It also has a nice crisp short throw shifter like the aftermarket units.

Tons of people use this. I had John York do all my work for me. He can give you all the lowdown on this, or Ed Combs (DV) or Don Scott

Ed

[renaissance man]

I try and use all of the gears as much as possible.

[blykins]

Here's a question for you Unique and ERA guys...

With the Salisbury rearend, are there are a lot of gearsets available? I know that it uses Dana 44 stuff, but I haven't really found a wide variety of gear ratios.

Also, are there different differentials available? i.e. Auburn, Detroit Locker...etc..

[ERA535]

blykins -

There are a pretty fair number of choices - in the range that we care about there are 3.08, 3.31, 3.55, 3.73's available.

There are different carriers and posi units available.

Check with Concours West Industries, they have a web site and they are good people to work with.

[Snake]

Hey There! I'm running a pretty much stock 302 H.O. with a few mods. The clutch is a stock ford, I think...it's been awile that I past that stage in my build up. It's my first build....so all let you razz me up a bit.....just a bit!! I've got 295x15 on the rear...and about who rides with me....well no one yet! Not finished....hope to have it done this summer....going to the paint shop in a week or two. So I was tring to find out what would be a good gear set-up to use.

I got another question....I'm using stewart warner gauges....how do you run the cable for the tach and the speedo...the cables seem to be short?

Thanks.
Snake

[blykins]

Snake, ERA535 gave a pretty good list of gear ratios to use. It all depends on what you want to accomplish. If you're running around the streets and want good gas mileage, stick with a moderately higher gear (lower number) like a 3.27. If you're running stoplight to stoplight constantly, you'll wanna go low...4.11, 4.30, etc. A good all-around gear is a 3.55 or 3.73. What kind of rearend are you using? Jag(Dana 44), 8.8", 9", 10-bolt Chevy? The reason I asked ERA535 that is because I'm looking into buying the Unique kit. I'm used to fooling with 8.8" Fords, and I know what ratios are available there...however I'm not familiar with a Dana 44. I plan to go with a 3.73 in my Cobra.

Hope this helps,

Brent

[Snake]

Thanks Brent! I got an 8.8 off of an 86 Mustang GT...not sure of the gears in it yet...the Mustang had a V6. I'll probably go with the 3.55....maybe the 3.73....all see what is around here for parts.
Thanks Buddy.
Gerry/snake.

[blykins]

You can snag a ring and pinion for around $185 down here in the States from Jegs or Summit Racing. If you've had the rearend cover off, sometimes the ratio is stamped on the end of the pinion gear. Otherwise you know you can check it by putting a mark on the driveshaft, and a mark on the axle hub....spin the driveshaft...count how many times you have to turn it to turn the mark on the hub around once. I'm sure you knew that, but it's a quick way to tell. I'm thinking since the Stang had a 6-banger in it, the gears may be low....you may already have a 3.55 or 3.73.

Take care and good luck.

Brent