Gears and RPM's

[fastblackmerc]

Did some checking with my 4.10's, Scangauge and 255 rears.

80MPH - 2755RPM
70MPH - 2470RPM
60MPH - 2068RPM
55MPH - 1934RPM

If some one can check their MM with 3.55's and Scangauge that would be great for a comparison.

OK, so let's add rear tire size.

Don't care about who's tune, because the tune's will be different... too many variables.

Just wanted to get some info out there for all the 4.10 questioners worried about how much faster the engine is turning.

[whitey]

Stock size tires, 3.55's
80MPH - 2397RPM
70MPH - 2100RPM
60MPH - 1795RPM
55MPH - 1633RPM

[lji372]

Saving spot for later. Ill check back in with my results.

Your a dork :lovies:

[whitey]

Your a dork :lovies:

Been called worse, by better:P

[ctrlraven]

Did some checking with my 4.10's and a Scangauge.

80MPH - 2755RPM
70MPH - 2470RPM
60MPH - 2068RPM
55MPH - 1934RPM

If some one can check their MM with 3.55's and Scangauge that would be great for a comparison.
You should also list the rear tire size you are using.

For me running a 265/50 rear tire this is what I have.
60MPH - 2035RPM

[HotRaud90]

Did some checking with my 4.10's and a Scangauge.

80MPH - 2755RPM
70MPH - 2470RPM
60MPH - 2068RPM
55MPH - 1934RPM

If some one can check their MM with 3.55's and Scangauge that would be great for a comparison.

Good info for people wonderin about the switch from 3.55 to 4.10/gas mileage. What tune do you have for it? Feel like that might be helpful info as well (maybe?).

[whitey]

Good info for people wonderin about the switch from 3.55 to 4.10/gas mileage. What tune do you have for it? Feel like that might be helpful info as well (maybe?).

Rpms wont change for a tune, shift points will.

[fastblackmerc]

You should also list the rear tire size you are using.

For me running a 265/50 rear tire this is what I have.
60MPH - 2035RPM

Will do, but a 33RPM difference.......

[fastblackmerc]

Good info for people wonderin about the switch from 3.55 to 4.10/gas mileage. What tune do you have for it? Feel like that might be helpful info as well (maybe?).

That's why I did it.

[ctrlraven]

Will do, but a 33RPM difference.......
I'll see at what other speeds my rpms are when I go home tonight.

[Vortech347]

Use a GPS for speed and an OBD-ii scanner for the RPM. 70mph with 255/55/18 NT850's is 2350.

[whitey]

From my calculations, i got approximately 21mpg going 78-80mph coming home from Louisville. Just did the math for 80 mph,
2397rpm X 21mpg=50337total rpms for 21 miles.-----stock 3.55
50337 Total rpm / 2755rpm= 18.27mpg-----------4.10's

21mpg-18.27mpg= 2.73 mpg less with 4.10 gears>>>about 52 miles less per tank of gas.

[ctrlraven]

4.10s with 265/50-18 in Overdrive
55MPH - 1860RPM
60MPH - 2035RPM
70MPH - 2381RPM
80MPH - 2701RPM

[justbob]

I have no voice here :(


Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

[1stMerc]

I have no voice here :(


Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

What sa matta you? Cat gotcha tongue?

[HotRaud90]

I feel the possibility of a sticky...

[Marauderjack]

I have no voice here :(


Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

^^Good One^^:beer::D

[PuntyMario]

how about 4.56 gears... if i had a scanner of some kind i could give you my insane numbers.

[crouse]

What is your RPM at 60 MPH in overdrive?

[Bluerauder]

how about 4.56 gears... if i had a scanner of some kind i could give you my insane numbers.

Multiply by 1.2845 for an estimate. They should be close to this for 4.56 gears ....

80MPH - 3539 RPM
70MPH - 3173 RPM
60MPH - 2656 RPM
55MPH - 2464 RPM

[fastblackmerc]

how about 4.56 gears... if i had a scanner of some kind i could give you my insane numbers.

I don't think we need to include 4.30 or 4.56 gears since the people that will be installing them are not on the fence about installing them.

[Blown3.8]

Here plug in what you like. http://vexer.com/automotive-tools/speed-rpm-calculator

4R70W ratios are: (1st) 2.84, (2nd) 1.55, (3rd) 1.00, (OD) .7

[whitey]

Here plug in what you like. http://vexer.com/automotive-tools/speed-rpm-calculator

4R70W ratios are: (1st) 2.84, (2nd) 1.55, (3rd) 1.00, (OD) .7
^^^this should be stickied!^^^why do you have to make things so easy Chris?

[PuntyMario]

Multiply by 1.2845 for an estimate. They should be close to this for 4.56 gears ....

80MPH - 3539 RPM
70MPH - 3173 RPM
60MPH - 2656 RPM
55MPH - 2464 RPM

Yeah thats about right. Not a fan of cruising at 2500 rpm but she feels strong.