Electronics-Lab.com Community

# help for rpm measurement

## Recommended Posts

ppl can any 1 of u tell me how to measure rpm of a car engine witout accessing it
from inside

##### Share on other sites

Hi rod,

Accessing from the inside of what, the engine or the car?

##### Share on other sites

Hi rod,

Accessing from the inside of what, the engine or the car?

actually i want to make a digital rpm indicator..........but dont hav enough knowledge abt car engine.....so without accessing the engine from inside
##### Share on other sites

It all depends on the engine and what

##### Share on other sites

If you know the HorsePower(HP) and the Torque of it, you can also find the RPM  ;)

Horsepower =2 (pi) S T/33,000

S = shaft speed in r.p.m.
T = shaft torque in lb-ft (pound-feet)

From this u can get    S= 33,000HP/ 2(pi)T

BTW, 1 Horsepower = 745.7Watts

:) :) :)

Hi NanOp,

I don

##### Share on other sites

Hi Ante,

* Mechanical horsepower

##### Share on other sites

I think that car engines are classified as mechanical. Also, if u want to be more exact, it would be 0.74569987158227022 kW or just 745.69987158227022 Watts

Ok, it

##### Share on other sites

If you know the HorsePower(HP) and the Torque of it, you can also find the RPM
##### Share on other sites

guys thanx 4 all ur replies  but i've got the answer to it

##### Share on other sites

Please share it with us  :)

-Nanop

Hi Ante,

##### Share on other sites

I guess it’s like comparing a gallon (inp. vs US) they are not even close!

Or a ton vs a tonne and a ton!
Or short ton = 907.2kg vs metric ton = 1000.0000000000000kg how stupid is that?  ;D

I stay with metric like Europe; it’s much simpler this way! 8)
Or perhaps one day there is only 907mm on 1 meter!? ;D

I guess it
##### Share on other sites

• 3 weeks later...

Hi NanOp,

I don
##### Share on other sites

I have had no luck in finding a metric horse    ;D

MP

## Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

×   Pasted as rich text.   Paste as plain text instead

Only 75 emoji are allowed.

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×