1/2 VW engines,

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Colin Dix
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Joined: Wed Jun 25, 2008 9:46 am

1/2 VW engines,

Post by Colin Dix » Sun Nov 21, 2010 9:10 am

Has anyone used or had experience with a 1/2 VW Engine in the UK. Is 50 HP possible? - I see several plans and options availabe in the US?

Or would a 2CV Aero engine be best for up to 50 HP?

Any ideas?

Thanks

Colin

G.Dawes
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Joined: Wed Jan 02, 2008 11:00 am

Post by G.Dawes » Sun Nov 21, 2010 7:28 pm

I do not think that you would get anything like that out of either of those two engines, the two cylinder VW is a bit of a botch and will vibrate a lot with a rocking couple, especially if you big bored it. I started making one but stopped when I realised the trouble getting to use it would bring. The 2CV is good for about 25 bhp and weighs a fair bit it would rev enough to get more without the use of a reduction gear.
if you need a twin then a ready made engine like the HKS for that purpose would be the easiest but dearest way.

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Rod1
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Location: Midlands

Post by Rod1 » Sun Nov 21, 2010 8:49 pm

I have been told that it is possible to get 50hp out of a Briggs & Stratton vanguard.

Rod1
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Brian Hope
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Location: Sheerness Kent

Post by Brian Hope » Mon Nov 22, 2010 6:54 am

The 1/2 VW engine has been flying successfully in the US for years, weighs around 85 -90 lbs (about the same as a RTF Rotax 447) and is reckoned to produce 30 - 40 hp depending on state of tune. A botch it is not, it is a well sorted conversion. The first UK built Hummelbird is about to fly with a half VW (a Scott Casler conversion) and as far as I know this will be the only example flying here. The other twin VW's here are Moslers (formally Global), a production conversion with a new cast crankcase rather than a cut down case as in the diy conversions. These production units have not been available for some years.
A reliable 50 hp is almost certainly not possible, and I would take any claims of over 40hp with a very large pinch of salt.
The 2CV or the DAF flat twins are both heavier and very unlikely to produce more power.

Colin Dix
Posts: 25
Joined: Wed Jun 25, 2008 9:46 am

Post by Colin Dix » Thu Nov 25, 2010 8:46 am

Thank you for the replies. I have a MW7 with a Rotax 503. I would like a 4 stroke engine to replace it.

Colin
Last edited by Colin Dix on Thu Nov 25, 2010 11:05 am, edited 1 time in total.

rans6andrew
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Post by rans6andrew » Thu Nov 25, 2010 10:34 am

I wanted to replace a 503 in a Rans with a 4 stroke but didn't want the cost or weight of a 912. The HKS 700 looks to fit the bill, Conrad at ConairSports (dotcodotuk) has been through the task of doing the first one and sussing out the mountings and cooling etc. If you move quickly there is a cheap HKS 700 on AFORS right now, for little more than the cost of a 503.

Good luck,

Rans6...
Andrew Cattell

Rans S6 Microlight.

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