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Yes, we do post about small engines.....
Alan B - 2/5/13 at 06:05 PM

But this guy seems to have made a great, fun business out of it...

linky

Great stuff and a good read too....

40inches - 2/5/13 at 07:35 PM

That supercharged 100cc V8 is.....well, it just is

puma931 - 2/5/13 at 08:23 PM

so cool

rf900rush - 2/5/13 at 09:39 PM

Posted this on a while ago

http://www.locostbuilders.co.uk/viewthread.php?tid=178875

[Edited on 2/5/13 by rf900rush]

clairetoo - 2/5/13 at 09:40 PM

I'm confused - if its quarter scale , shouldnt it be closer to 2 litre , after all , how many 400 cc V8's are there ?

Just sayin'....................

Alan B - 2/5/13 at 09:48 PM

quote:
Originally posted by clairetoo
I'm confused - if its quarter scale , shouldnt it be closer to 2 litre , after all , how many 400 cc V8's are there ?

Just sayin'....................





1/4 linear scale....equates to 1/4 x 1/4 x 1/4 volumetrically.....or 1/64......approx 6.4 litres



rf900rush....that was really the meaning of my title......yes, we've seen stuff like this before...didn't realise you'd posted the exact thing though....my apologies to those who have seen it before..

Ninehigh - 3/5/13 at 07:12 AM

I wonder what ratio the power goes down, 1/4 or 1/64?

hughpinder - 3/5/13 at 07:56 AM

It says the supercharged engine makes 9hp - so pretty good power to weight ratio for a model engine .
Hugh

Fred W B - 3/5/13 at 11:19 AM

quote:

I wonder what ratio the power goes down, 1/4 or 1/64?


An equation for HP = PLANK where

P= bmep (combusion pressure)
L= length of stroke
A= piston area
N = revs per minute
K = a constant

so it will be the smaller one

Cheers

Fred W B

Alan B - 3/5/13 at 11:27 AM

quote:
Originally posted by Fred W B
quote:

I wonder what ratio the power goes down, 1/4 or 1/64?


An equation for HP = PLANK where

P= bmep (combusion pressure)
L= length of stroke
A= piston area
N = revs per minute
K = a constant

so it will be the smaller one

Cheers

Fred W B



Yes indeed.

Along with weight and volume the power will be scaled by the linear scale cubed.......ie: 1/64
So at 5hp x 64 = 320hp.....which is about what you'd expect from a low tech (no offence) 6.4 litre V8......IOW around 50hp/litre.