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what rpms w/ 373s

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Old 08-05-2012, 04:24 PM
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Default what rpms w/ 373s
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.
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Old 08-05-2012, 05:58 PM
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if 2.73s'=2100,then 3.73s' would =2870
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Old 08-05-2012, 07:12 PM
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Originally Posted by FirstYrLS1Z
if 2.73s'=2100,then 3.73s' would =2870
i was around 3k when i had 3.73s at 70mph.
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Old 08-05-2012, 07:41 PM
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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.
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Old 08-05-2012, 07:42 PM
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Originally Posted by redtan
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.
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Old 08-05-2012, 08:08 PM
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I guess they dont teach math in schools anymore!
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Old 08-05-2012, 08:33 PM
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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'.
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Old 08-05-2012, 10:03 PM
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Originally Posted by FirstYrLS1Z
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
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Old 08-05-2012, 11:12 PM
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By the factory tach:
3.23s 2k @ 68mph
3.73s 2450 @ 68-70mph
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Old 08-06-2012, 06:03 AM
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"Just to be clear, my comment was directed at the OP"

I took your comment as intended for the OP.
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Old 08-06-2012, 07:13 AM
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Originally Posted by ultimateorangess
i was around 3k when i had 3.73s at 70mph.
(2100/2.73)*3.73=2869rpm
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Old 08-06-2012, 07:25 AM
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Originally Posted by StraightTimeStirrups
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.
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Old 08-06-2012, 09:57 AM
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Originally Posted by StraightTimeStirrups
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
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Old 08-06-2012, 11:38 AM
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lol...
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Old 08-06-2012, 05:46 PM
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I ran 1900rpm at 70mpg with 2.73s, now I run 1900 rpm at 55mph....about 2400rpm at 70
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Old 08-06-2012, 05:54 PM
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2400 is fine. Anyone know the difference between 0to60? My buddy who is going to pay half wants to know before it gets done?
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Old 08-07-2012, 12:23 AM
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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.
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Old 08-07-2012, 08:24 AM
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Originally Posted by 1981TA
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.
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Old 08-08-2012, 07:37 PM
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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.
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Old 08-08-2012, 09:19 PM
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Originally Posted by justin hover
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.
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