Camaro_3245

So I have been running a T56 magnum after I broke my 3-4 shift fork in my stock T56, yes had to get the drive line cut and odometer still wrong... The real question I have is the ratio that I have (2.97, 2.10, 1.46, 1, .74, .50) which I wanted because of the last two gears were same ratio as stock T56, how will it affect my quarter mile time with longer gears?

As you know there were two options for T56 magnums
Short- (2.66, 1.78, 1.30, 1, .80, .63) which is prolly better for track
Long- (2.97, 2.10, 1.46, 1, .74, .50) bad for track? Or just not optimal?

Next question what kinda rear end gears y'all would think I should get with my 9in rear end? Good street and track 4.10?

I want to keep gas mileage in mind I do like to run outta town on a weekend some times

Oh and I got aluminum pressure plate and fly wheel... And thoughts about how this May affect my track time I know less rotating mass for the launch but make up for it with higher rpm on launch but kids scary with stock rear end????

Camaro_3245

Somebody anybody I ain't good with ratios :-/

Exidous

iTrader: (11)

You are missing a lot of information. Weight, rear gear, power, max rpm.

Generally speaking you want to finish in 4th and it's 1:1 for both transmissions(drag strip). You will match you rear gear and tire to the MPH you expect to pull. 5th and 6th only really come into play for standing mile pulls.

If by track time you mean race track then the 2.66 - .63 is a no brainer.

My gearing and tire make 4th top out at 117 with a 6600 redline. At my power and weight I need to be at least at 128 so I am changing to a 3.55 rear.

BlackLS1Bird

iTrader: (2)

You have the Ford gearing in yours. You may have the long and short backward. The numerically higher a gear ratio goes, the lower or shorter the gear is. Picture 3.42 rear gears compared to 4.10 gears. The 2.97, 2.10, 1.46 should technically help your quarter mile times because the car should accelerate faster just as with a rear gear change, but with the very small differences in the ratios between the Ford and GM, I doubt you will see any difference. There are all of the other typical factors to take into account.

.boB

iTrader: (1)

There is no perfect rear gear, unless the car is strictly dedicated to one purpose. Everything else becomes a compromise.

For the street, I like to base the rear gear on the upper gear (6th), your average cruising speed, and where the power band is.

For example. I have a small light weight car with a big radical engine. The power band doesn't really come on until about 2,000 rpm's. I routinely cruise the highway at 80mph. Using a 3.55 gear, that puts me right around 2,400 rpm. That seems kinda high, but for my engine it's right where it should be, right into the power band. The engine hums along and gets about 20mpg. If traffic slows to 65 - as it often does - I don't need to down shift. I have a TKO 5 speed, and there's about a 1,000 rpm drop between 4th and 5th.

For my car, engine, and driving, the 3.55 works out perfect. But if I lived where I routinely cruise at 55-60mph, then I would need either a 3.73 or 4.11.

You need to take a realistic look at your car and your driving, and then use the calculators to decide what's going to put you in the sweet spot.

I prefer alum flywheels. They rev up quicker.

SNLPerformance

iTrader: (15)

Need to know your goals with car, to determine which is better for your application starting with the power and what size tire you plan on running.

The 2.97 first gear will help get you out of the hole better and allow you to not run as steep (high numerically) of a rearend gear for mpg with the same overall 1st gear multiplication, though I'd gear it for the top of 4th for the 1/4 as mentioned. The 2.66 does have better shift extension or less rpm drop on the 2-3 and 3-4 shift which can be beneficial depending on the powerband or if you are willing to run the gear needed to give the same acceleration, it's all a trade off.

SSSTANG#1

iTrader: (14)

To OP, like said above, your Magnum gears are lower (shorter) than original T56.

I Just picked up a Ford geared Magnum with the 2.97 1st. I have a 4.10 in the rear and hope that the .50 6th isn't too tall for highway cruising below 80 mph. The engine will be a 454.