# Gears & Axles - what rpms w/ 373s

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Carguy8888
08-05-2012, 05:24 PM
What rpms will i be turning at 70mph going from a 273 (2100 rpms) to a 373 rear w/ factory wheels?
Also, my friend asked me how many tenths will i save from 0 to 60? I didn't know how to answer him. I am a seat of pants kind of guy. I think it is 4.9 stock but I am not sure? Thanks. Brian.

FirstYrLS1Z
08-05-2012, 06:58 PM
if 2.73s'=2100,then 3.73s' would =2870

ULTIMATEORANGESS
08-05-2012, 08:12 PM
if 2.73s'=2100,then 3.73s' would =2870

i was around 3k when i had 3.73s at 70mph.

redtan
08-05-2012, 08:41 PM
if 2.73s'=2100,then 3.73s' would =2870

How did you figure that?

An online calculator shows 2400rpm @ 70mph with the new gearing the OP mentioned.

i was around 3k when i had 3.73s at 70mph.

Surely that wasn't with a 4L60E transmission unless you had like 24" tires.

ULTIMATEORANGESS
08-05-2012, 08:42 PM
How did you figure that?

An online calculator shows 2400rpm @ 70mph with the new gearing the OP mentioned.

Surely that wasn't with a 4L60E transmission unless you had like 24" tires.

lol youre right. i was around 2400. ive made this mistake before. :emb:

StraightTimeStirrups
08-05-2012, 09:08 PM
I guess they dont teach math in schools anymore!

FirstYrLS1Z
08-05-2012, 09:33 PM
true rpm,not factory tach as they generally indicate way too high,would be 2.73s'=1750 and 3.73s'=2400

the 2870 came from 'math' based on the OPs' 2100 with 2.73s'.

StraightTimeStirrups
08-05-2012, 11:03 PM
true rpm,not factory tach as they generally indicate way too high,would be 2.73s'=1750 and 3.73s'=2400

the 2870 came from 'math' based on the OPs' 2100 with 2.73s'.

Just to be clear, my comment was directed at the OP. It is a simple math problem and I cringe every time I see a question like this! It took him longer to ask the question then to do the simple math!

Joe

01ssreda4
08-06-2012, 12:12 AM
By the factory tach:
3.23s 2k @ 68mph
3.73s 2450 @ 68-70mph

FirstYrLS1Z
08-06-2012, 07:03 AM
"Just to be clear, my comment was directed at the OP"

I took your comment as intended for the OP.

Ethan[ws6]
08-06-2012, 08:13 AM
i was around 3k when i had 3.73s at 70mph.

(2100/2.73)*3.73=2869rpm

Carguy8888
08-06-2012, 08:25 AM
Just to be clear, my comment was directed at the OP. It is a simple math problem and I cringe every time I see a question like this! It took him longer to ask the question then to do the simple math!

Joe

I am not a gearhead & did not know the simple math as you call it. If my question upset you so much you did not have to reply.
Thanks everyone else.

01ssreda4
08-06-2012, 10:57 AM
Just to be clear, my comment was directed at the OP. It is a simple math problem and I cringe every time I see a question like this! It took him longer to ask the question then to do the simple math!

Joe

Settle down cutie :gay:

ULTIMATEORANGESS
08-06-2012, 12:38 PM
lol...

justin hover
08-06-2012, 06:46 PM
I ran 1900rpm at 70mpg with 2.73s, now I run 1900 rpm at 55mph....about 2400rpm at 70

Carguy8888
08-06-2012, 06:54 PM
2400 is fine. Anyone know the difference between 0to60? My buddy who is going to pay half wants to know before it gets done?

1981TA
08-07-2012, 01:23 AM
The difference for 0-60? It depends on many factors in the car, of which the axle ratio is just one. It will certainly be noticeable though.

Carguy8888
08-07-2012, 09:24 AM
The difference for 0-60? It depends on many factors in the car, of which the axle ratio is just one. It will certainly be noticeable though.

Makes sense thank you.

justin hover
08-08-2012, 08:37 PM
Everyone say's track gains are very minimal, I felt I picked up alot sotp. It truly "feels"
2x faster off the line. No more 3rd gear lag. Can finally do a burnout without power braking with ease.

Carguy8888
08-08-2012, 10:19 PM
Everyone say's track gains are very minimal, I felt I picked up alot sotp. It truly "feels"
2x faster off the line. No more 3rd gear lag. Can finally do a burnout without power braking with ease.

Sounds good.