Which Gears Should I Get?

cobrajeff96

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You'd probably notice an equal amount of difference going with lightened flywheel, aluminum driveshaft, machine-lightened ring gear, lightweight harmonic balancer, lighter wheels and rotors, etc. Maybe even more than just the gear ratio with all those combined.
 

badass98svt

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You'd probably notice an equal amount of difference going with lightened flywheel, aluminum driveshaft, machine-lightened ring gear, lightweight harmonic balancer, lighter wheels and rotors, etc. Maybe even more than just the gear ratio with all those combined.
Maybe, but that's much more than the $600-$800 a new diff and gears would run
 

Terrorist 5.0

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You'd probably notice an equal amount of difference going with lightened flywheel, aluminum driveshaft, machine-lightened ring gear, lightweight harmonic balancer, lighter wheels and rotors, etc. Maybe even more than just the gear ratio with all those combined.
Where would you get half the stuff though? I’ve never seen a lightweight harmonic balancer or brake rotors (unless your talking about the racing ones which cost a fortune and are miserable on the street)
 

duh09

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All I know is don't fear the gear.

I had 4.10s in my white car, loved them.
I had 3.73s in my white fox coupe, liked them.
I had 3.55s in the Mystic, they were ok but a 4V got a lot more RPM to play with so it really wanted some deeper gears.
I had 3.27s in the red car, they were meh.
I had 2.73s in my teal car, cried a lot about that.

All those cars were pretty much stock/bolt-on cars.

I might be a little pickier about my gear choice with the Cobra but it ought to be easily double the power of the other cars, it'll probably land in the 3.55/3.73 range. I got not a clue what's in it now.
 

cobrajeff96

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Where would you get half the stuff though? I’ve never seen a lightweight harmonic balancer or brake rotors (unless your talking about the racing ones which cost a fortune and are miserable on the street)
Perhaps the only thing that might feel awkward is the aluminum flywheel. Ran one of those two different times and boy did it free up power. But it can be a bit.... jerky. Most of your aftermarket balancers are lighter weight than OEM, such as the ATI. Wilwood makes excellent rotots that are definitely lighter than OEM steel. There's really no downside to running those kind of aftermarket rotors. Car will brake quicker, wheels turn faster, suspension is more reactive, and less overall weight.
 

Musturd

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Yes you can get an increase in MPG around town with a ring and pinion change. The engine doesn't have to work as hard to get up to speed because it doesn't have to lug through low RPM as long. The highway MPG can actually get better too, depending on the speed. The best way to monitor any change would be either to monitor engine vacuum during driving (U-Haul trucks have that as a measure to help the average person save fuel), or to monitor the TPS readings as you drive. The higher the vacuum/lower the TPS reading, the better fuel economy you can get. On a personal note, I ride around in 4th all the time with my 3.08 axle. I keep RPM at about 1200-1300 RPM and just rest my foot on the pedal. Keeps the car quiet, and I get great fuel economy (relative to other SN95 cars).


Running your car at 1800 rpm isn’t better on fuel on the highway in 5th . The sweet spots around 22-2400 . The car makes no torque there and over fuels . I’ve had these shit box’s for the last 20 years . Even my f150 got better milage going from 3.31’s to 3.73’s
 

Terrorist 5.0

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Perhaps the only thing that might feel awkward is the aluminum flywheel. Ran one of those two different times and boy did it free up power. But it can be a bit.... jerky. Most of your aftermarket balancers are lighter weight than OEM, such as the ATI. Wilwood makes excellent rotots that are definitely lighter than

Running your car at 1800 rpm isn’t better on fuel on the highway in 5th . The sweet spots around 22-2400 . The car makes no torque there and over fuels . I’ve had these shit box’s for the last 20 years . Even my f150 got better milage going from 3.31’s to 3.73’s
I would think speed is a big factor though, 1800 RPM at 80 MPH is too little, but at 60 MPH, should be perfectly fine. I am not as experienced as you are on these cars, but at what speed would 2200-2400 RPM yield you the best fuel economy? I would imagine you are talking maybe 75-80 MPH?
 

badass98svt

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I would think speed is a big factor though, 1800 RPM at 80 MPH is too little, but at 60 MPH, should be perfectly fine. I am not as experienced as you are on these cars, but at what speed would 2200-2400 RPM yield you the best fuel economy? I would imagine you are talking maybe 75-80 MPH?
80 mph with 4,30 will put you around 2800 RPM
I bet 2400 is about 70 mph in 5th gear
 

weendoggy

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I have 3:73 gears, aluminum driveshaft and ATC flywheel. 70mph is about 2000 in 5th. The ATC is just a bit heavier than an aluminum flywheel, but cheaper. Gears will wake up the car for normal street, but be comfortable for daily diving. Going to 4:10 will be agressive, but you pay for noise/drone.
 

MachSVT

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Disclaimer: I skimmed through the responses, but didn't see these counterpoints:

1. What is your primary use case?
2. What is your current power level and / or desired power level?

For a street car:

Lowest power - 4.10
Medium power - 3.73
Higher power - 3.55

Example:

My car is an Eaton swapped Mach 1, stock bottom end, pretty much every bolt-on except supercharger upgrade and lower pulley swap (still 03 / 04 Cobra crank support). H.P. to the tire is 470 on 10 lbs. boost. I don't recall TQ atm. My rear gear is 3.73, trans is close ratio T56 Magnum (numerically lower 1st & 2nd gear) where the wide ratio has a steeper 1st & 2nd. I run 200 treadwear 315 x 30 x 18's. I could run 100 treadwear / drag radials, but the car is more all purpose than street / drag. Anyway, enough on that mess...

3.73 on my combination is the lowest I should go on my combo based on available traction. On cooler / moderate heat days, 3rd gear skips for traction. More towards winter, it will roll the tires merging onto the interstate in 3rd. A 6 speed is great, but if you spn through half of them, I don't consider that car a well thought out street car.

My aspirations for the car is 650 + on the very low end and likely closer to 800. With that power level, 3.73 will be ice capades.

Long story short, I will switch back to (stock) 3.55's. Gear the car for your power goals.
 
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muzamill_717

muzamill_717

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Disclaimer: I skimmed through the responses, but didn't see these counterpoints:

1. What is your primary use case?
2. What is your current power level and / or desired power level?

For a street car:

Lowest power - 4.10
Medium power - 3.73
Higher power - 3.55

Example:

My car is an Eaton swapped Mach 1, stock bottom end, pretty much every bolt-on except supercharger upgrade and lower pulley swap (still 03 / 04 Cobra crank support). H.P. to the tire is 470 on 10 lbs. boost. I don't recall TQ atm. My rear gear is 3.73, trans is close ratio T56 Magnum (numerically lower 1st & 2nd gear) where the wide ratio has a steeper 1st & 2nd. I run 200 treadwear 315 x 30 x 18's. I could run 100 treadwear / drag radials, but the car is more all purpose than street / drag. Anyway, enough on that mess...

3.73 on my combination is the lowest I should go on my combo based on available traction. On cooler / moserate heat days, 3rd gear skips for traction. More towards winter, it will roll the tires merging onto the interstate in 3rd. A 6 speed is great, but if you spn through half of them, I don't consider that car a well thought out street car.

My aspirations for the car is 650 + on the very low end and likely closer to 800. With that power level, 3.73 will be ice capades.

Long story short, I will switch back to (stock) 3.55's. Gear the car for your power goals.
Ima do the 4.10s
 

Musturd

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Disclaimer: I skimmed through the responses, but didn't see these counterpoints:

1. What is your primary use case?
2. What is your current power level and / or desired power level?

For a street car:

Lowest power - 4.10
Medium power - 3.73
Higher power - 3.55

Example:

My car is an Eaton swapped Mach 1, stock bottom end, pretty much every bolt-on except supercharger upgrade and lower pulley swap (still 03 / 04 Cobra crank support). H.P. to the tire is 470 on 10 lbs. boost. I don't recall TQ atm. My rear gear is 3.73, trans is close ratio T56 Magnum (numerically lower 1st & 2nd gear) where the wide ratio has a steeper 1st & 2nd. I run 200 treadwear 315 x 30 x 18's. I could run 100 treadwear / drag radials, but the car is more all purpose than street / drag. Anyway, enough on that mess...

3.73 on my combination is the lowest I should go on my combo based on available traction. On cooler / moderate heat days, 3rd gear skips for traction. More towards winter, it will roll the tires merging onto the interstate in 3rd. A 6 speed is great, but if you spn through half of them, I don't consider that car a well thought out street car.

My aspirations for the car is 650 + on the very low end and likely closer to 800. With that power level, 3.73 will be ice capades.

Long story short, I will switch back to (stock) 3.55's. Gear the car for your power goals.
If you’re making that kind of power I’d be daily driving on a drag radial .
 

MachSVT

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If you’re making that kind of power I’d be daily driving on a drag radial .
You're on bigs / littles, yes?...more of a straightline car?

For that I would just get a drag pack.

I like some twisty stuff / handling, also...dual purpose.
 

Musturd

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B8F06A54-71F9-41E4-A298-2183235368E7.jpeg lol I’ve got multiple sets of wheels and run 275/40/17 nitto 555r2’s drag radials for when I wanna run twisty stuff . I don’t run radials on my drag setup radials are dog shit on a stick car for drag racing but good on the street .
 

MachSVT

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View attachment 40182 lol I’ve got multiple sets of wheels and run 275/40/17 nitto 555r2’s drag radials for when I wanna run twisty stuff . I don’t run radials on my drag setup radials are dog shit on a stick car for drag racing but good on the street .
Agree...just not there yet with all the planned changes ahead of it.

I'll get it done, but the car has been so much better on the street that I was enjoying it too much to take it all back apart just yet.

To your point, both stickier street tires and a drag pack are in order. I buy those now, I'll blow the b*tch up for sure! Radials are helping it live for now.
 

Musturd

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Nice , cars probably a ton of fun with the power it makes .
 

shovel

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Reported.


(edit to answer the question below, there was a crypto spammer which has been dealt with by mods, making this post appear out of place)
 
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