off topic....

hi, i`m trying to find if theres a table or calculator online that will allow me to plug in a diameter of a hole in mm (i.e 1.5 mm , carburettor jet ..) then plug in the % increase ... i.e 33 % , , then hopefully that will tell me what size drill to use to acheive a 33 % in size of hole.

i`ve had a darn good look , but i cannot find anything !!

mark

spreadsheet?

Crikey, a four-second Excel spreadsheet exercise.

Empirically is the usual way explain what you are doing as there may well be some one with a clue how to get you close

sorta but carb model and on what it's easy to find a close to

and you computer clock needs fixing

ummmm i know crap all about spread sheets and such.....

its like asking you to do something which you have NO KNOWLEDGE about ...... thats why i ask here,.,...

mark

hi, i thought i did explain what i am doing !!!

Hi,

I'm assuming you have a calculator that has "pi", "squared" and "square root" buttons.

Proceed as follows:

(radius of existing jet) [squared] [multiply] [pi] [multiply] (area increase) [divide] [pi] [=] [square root]

This will give you the required radius.

(....) are numbers you enter

Your area increase of 33% should be entered as 1.33

The radius is half the diameter (I'm assuming you already know this but .....)

The answer is 1.73mm diameter.

Hope this all makes sense.

p.s. In this case you can enter the the diameter instead of the radius and the answer will the be the required diameter.

it is if you can use a calculator BUT I see you are intent in not telling us about the physical facts of the rejet

didnt you read it , all i want to do is plug in the diameter of a hole , then plug in the % increase i want , then i want it to tell me what size drill to use....... simple.....

hi, finally a excellent answer....... someone understood.............

yay !!!!!!

thanks....

mark ..

mmm its very simple you just complicate things.....

i actually have a jet with a 1.17 mm hole ...... i want to increase it by 33% .... what size drill do i use... simple..... physical facts ???????? i`m using a differant fuel, and i have to flow 33% more of this type of fuel.. very simple,

mark k

ah ok so methanol boost that why I run big injectors and a hand built cpu ok well use your calculator and you know how

Can you drive a slide rule?

buttons.

answer will the be the required diameter.

Can you explain why you felt the need to include pi in the equation? You don't need to calculate the actual_area, just the ratio.

So the O/P enters the required ratio (1.33 as you indicated for his example 33% CSA increase), take the square root, and multiply that by the original size.

Have to be my age or an engineer to know ?

mark krawczuk Inscribed thus:

Diameter divided by 100 times 100 plus the percentage ie