Author Topic: Power calculation  (Read 3603 times)

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Darrell

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Power calculation
« on: February 02, 2009, 10:53:30 AM »
Ok so with this snow, cannot go to work and cannot play with the car so I was wondering if there were a formula to work out power.

I found one..

Alas I am either as thick as a brick or there is some stuff I have never heard of..

BHP = PLAN/33,000

P is brake mean effective pressure, in PSI
L is piston stroke, in feet
A is the area of one piston, in square inches
N is the number of power strokes per minute
Brake Mean Effective Pressure (BMEP)

4 stroke BMEP = (HP x 13000)/(L x RPM)

How the heck do you find out the HP when you have know it to work out the power!

I was wondering what the theoretical hp rating of our engines is :)

You never know, they may have missed a trick  [-/
'84 aircooled 126 & 500F still in kit form
Not the only African in the village :)

bis13

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Re: Power calculation
« Reply #1 on: February 02, 2009, 11:29:07 AM »
darrell dear boy go outside and make snowmen like everyone else..lol the power of the 126 engine is just above a hamster ...

MaLi

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Re: Power calculation
« Reply #2 on: February 02, 2009, 12:03:14 PM »
Interesting...

It reminds me a bit pre-war RAC formula for hp.

If you have some time you could try to play with Engine Analyser (a sort of simulation software) - you might be able work out some tips for getting more bhp from an aircooled engine.


126dave

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Re: Power calculation
« Reply #3 on: February 02, 2009, 12:15:01 PM »
for standard engines take the official fiat hp figure and subtract 10%, for tuned engines, think of a HP figure that will allow you to sleep at night after all the £ and euro spent on 'abarth' bits. i found '40+bhp' allowed me to sleep soundly...... ;)
28-34c and cold beers in the fridge

Darrell

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Re: Power calculation
« Reply #4 on: February 02, 2009, 12:19:59 PM »
Wow 40 +
Did it make a huge diference to the car?
'84 aircooled 126 & 500F still in kit form
Not the only African in the village :)

126dave

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Re: Power calculation
« Reply #5 on: February 02, 2009, 12:22:04 PM »
Wow 40 +
Did it make a huge diference to the car?

yes, mostly because my wallet was so much lighter lol
28-34c and cold beers in the fridge

Darrell

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Re: Power calculation
« Reply #6 on: February 02, 2009, 12:31:22 PM »
Hey ho, like all good woman they are good at wallet lighten-ing [-/

At least my little red lady doesn't get in a mood...you know the one....picture no sound is what I call it.
'84 aircooled 126 & 500F still in kit form
Not the only African in the village :)

126dave

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Re: Power calculation
« Reply #7 on: February 02, 2009, 03:15:37 PM »
lol funny you should say that, mine used to do that....when the 40dcoe had decided to part company with the engine YET AGAIN, or the engine tin had self destructed YET AGAIN,.....lots of silent moods in the workshop.....
28-34c and cold beers in the fridge

dajwid

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Re: Power calculation
« Reply #8 on: February 02, 2009, 04:12:36 PM »
Allegro (Polish Ebay type of thingy) often has 'tuned' 126 with 50 60 and even 70BHP just by changing parts costing less than a tenner. ;)

Fantastic.

Another method is 1 BHP for every £2 you spend on tuning parts.

Pick a number add a few and thats what you tell your mates at the pub.

I always thing my cars have more power when I have given them a good clean. [-/


hudsonhenry

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Re: Power calculation
« Reply #9 on: February 03, 2009, 09:53:38 AM »

Another method is 1 BHP for every £2 you spend on tuning parts


If only that were true!!!

I would have at least 3000bhp by now.... ;D

http://www.retro500.com the site dedicated to modified Fiat 500's

nathan126

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Re: Power calculation
« Reply #10 on: February 03, 2009, 11:24:21 AM »
new email address: [email protected]

goombas

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Re: Power calculation
« Reply #11 on: February 05, 2009, 09:54:44 PM »
its a good choice i have to say as for braeking down of old fiat engines or tuned ones
...if good thought that frontwheeldrive is better we would ended up walking on hands...