What will RPMs be with 373 gears in auto

MrPerfect2

Active Member

Jul 23, 2019

301

61

38

Washington DC

Oct 4, 2019

#1

• Oct 4, 2019

• #1

I have 327 gears in - rpm 1850 @ 65mph - any idea on rpm with 373 or 410s

 

FastDriver

My dad had a bra

SN Certified Technician

Sep 5, 2001

5,323

1,926

224

Vass, NC

Oct 4, 2019

#2

• Oct 4, 2019

• #2

I'm not an auto guy. Does the converter slip or lock up? If it slips, how much?

 

Rdub6

So while I wait to figure out my rear end issues

5 Year Member

Dec 29, 2017

3,684

2,885

153

Long Island, NY

Oct 4, 2019

#3

• Oct 4, 2019

• #3

Gear Ratio Calculator

Gear Ratio Calculator

www.tremec.com

 

FastDriver

My dad had a bra

SN Certified Technician

Sep 5, 2001

5,323

1,926

224

Vass, NC

Oct 4, 2019

#4

• Oct 4, 2019

• #4

Rdub6 said:

Gear Ratio Calculator

Gear Ratio Calculator

www.tremec.com

Click to expand...

I notice that calculator does not allow for converter slip. So, basically, he could use that and then multiply by (1- slip%) to get the speed.

 

MrPerfect2

Active Member

Jul 23, 2019

301

61

38

Washington DC

Oct 5, 2019

#5

• Oct 5, 2019

• #5

Is tremec only for sticks not auto

 

96pushrod

I think they're a little easier to get off

5 Year Member

May 15, 2018

1,530

968

133

Savannah

Oct 5, 2019

#6

• Oct 5, 2019

• #6

MrPerfect2 said:

Is tremec only for sticks not auto

Click to expand...

Really it’ll be close enough.

 

Reactions: 1 user

pats91

15 Year Member

Mar 6, 2007

118

73

48

Gladstone, MO

Oct 5, 2019

#7

• Oct 5, 2019

• #7

Try this one:

Simple RPM Calculator | RANDYS Worldwide

To find your vehicle’s RPM enter your Ring and Pinion Gear Ratio, Tire Height and Speed and press "Solve".

www.randysworldwide.com

 

FastDriver

My dad had a bra

SN Certified Technician

Sep 5, 2001

5,323

1,926

224

Vass, NC

Oct 6, 2019

#8

• Oct 6, 2019

• #8

MrPerfect2 said:

I have 327 gears in - rpm 1850 @ 65mph - any idea on rpm with 373 or 410s

Click to expand...

So, let's just make this easy, though my engineering/physics mind would prefer all the data:
373/327 * 1850 = 2110 RPM
410/327 * 1850 = 2319 RPM.

The answers should be as accurate as your RPM estimate is.

 

J

junkyardwarrior

Well-Known Member

Jan 10, 2011

398

119

63

Oct 7, 2019

#9

• Oct 7, 2019

• #9

What auto are you talking about? AOD? C4? Powerglide? C6? 4R70W? AODE? A904? AXOD????

 

Real time recon

Mustang Master

Aug 21, 2016

469

208

83

...

Oct 7, 2019

#10

• Oct 7, 2019

• #10

Don't know about Auto trans. But I'm pushing 1,500 RPMs... at 50 MPH... in 5th gear. with 373 posi

 

MrPerfect2

Active Member

Jul 23, 2019

301

61

38

Washington DC

Oct 7, 2019

#11

• Oct 7, 2019

• #11

Its a 91 AOD

 

FastDriver

My dad had a bra

SN Certified Technician

Sep 5, 2001

5,323

1,926

224

Vass, NC

Oct 7, 2019

#12

• Oct 7, 2019

• #12

Real time recon said:

Don't know about Auto trans. But I'm pushing 1,500 RPMs... at 50 MPH... in 5th gear. with 373 posi

Click to expand...

Enlightening! Well, the 3.73s with my viper-spec trans have me at 975 rpm at 42 mph.

 

pats91

15 Year Member

Mar 6, 2007

118

73

48

Gladstone, MO

Oct 7, 2019

#13

• Oct 7, 2019

• #13

~2000 rpm at an indicated 65 (My speedo is fairly accurate, checked with GPS)
1991 LX 3.73's, AOD w/lockup converter, 245/45/17 tires (25.70" theoretical diameter)
OD ratio in an AOD is 0.67/1.

 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor

Admin Dude

Jan 4, 1985

36,586

17,444

234

Box behind Walmart

Oct 7, 2019

#14

• Oct 7, 2019

• #14

I went the other way. I added torque and horse power instead of a reduction gear.

 

Reactions: 1 user

MrPerfect2

Active Member

Jul 23, 2019

301

61

38

Washington DC

Oct 7, 2019

#15

• Oct 7, 2019

• #15

Got to check my tire height - 30 years ( maybe the gears have been changed )

 

MrPerfect2

Active Member

Jul 23, 2019

301

61

38

Washington DC

Oct 30, 2019

#16

• Oct 30, 2019

• #16

I have 225/60/16 on stock pony rims - when tire change is needed , if I drop down in height a bit to a 55 or 50 it should give more off line torque ? It will harden the ride a bit with less air though and may look too short on tires - maybe a half inch drop in height would be nice compromise before I do gears ( 373 sound reasonable for daily driver with highway option )

 

a91what

SendMeUrDataLog

Mod Dude

Apr 6, 2011

10,751

6,964

214

Hillsborough county

Oct 30, 2019

#17

• Oct 30, 2019

• #17

I would not put smaller tires on the car, gears are much cheaper than tires are.

 

Rdub6

So while I wait to figure out my rear end issues

5 Year Member

Dec 29, 2017

3,684

2,885

153

Long Island, NY

Oct 30, 2019

#18

• Oct 30, 2019

• #18

It will have an effect on gear ratio and make it higher (number). Whether it will effect it enough to notice, I doubt it. It will, however make your speedometer off enough where you’ll probably notice that!

 

CarMichael Angelo

my rearend will smell so minty fresh,

15 Year Member

Nov 29, 1999

10,641

9,253

234

Birmingham, al

Oct 30, 2019

#19

• Oct 30, 2019

• #19

MrPerfect2 said:

I have 225/60/16 on stock pony rims - when tire change is needed , if I drop down in height a bit to a 55 or 50 it should give more off line torque ? It will harden the ride a bit with less air though and may look too short on tires - maybe a half inch drop in height would be nice compromise before I do gears ( 373 sound reasonable for daily driver with highway option )

Click to expand...

The tires, and or the rear end ratio do not affect the rwtq in any way.
The engine will make the same rwtq number with a 2.73 or a 3.73 rear gear set regardless.

 

MrPerfect2

Active Member

Jul 23, 2019

301

61

38

Washington DC

Oct 30, 2019

#20

• Oct 30, 2019

• #20

Yes I realize the actual torque produced won’t change - I am talking the feel of torque