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Bugat5speed
November 14th 2007, 12:07
Hi together,

am currently in the status of building a 4-valve DOHC-engine for Beetle and similiar cars. Can find some pics on my site under "Projekte". Have engineered a complete new cylinderhead plus camboxes, manifolds, etc...
Do this project together with Robert Bernauer from RMB www.rbernauer.de.
The engine will be based on a crank with 5 bearings and so will easily stand the high revving that we expect.
We think the engine will easily be around 90 PS per 1000cc. Biggest capacity will be 2.500 cc.
In a few weeks the first heads will be casted. Now that I have my milling centre and CAD/CAM it will be much easier to bring the project forward. Will keep you posted on this project.

Will attach some pics, when made them smaller (85 kb is not much).

Martin Bott
Bug @ 5-Speed
Bugat5speed
November 14th 2007, 13:49
here are at least two PDFs of the construction model.

More soon

Martin
Trogdor
November 15th 2007, 03:20
Looks like Porsche 4 cam heads. Cool beans.
Cohibra45
November 15th 2007, 18:30
Martin,

I sure would like to see you guys and the other teams:

http://www.apfelbeck.nl/

http://www.pro-machining.com/

http://www.aircooledtechnology.com/vw.htm

get together and form a true international consortium group. All could share information, ideas and most importantly costs/rewards. This should make all concerns time lines much quicker. The different styles of heads, Jakes push rod 'Porkies', apfelbeck single ohc 3 valve, and your dohc 4 valve. I'm sure that each will have different costs/uses and the resulting benefits for all the VW aircooled community will be tremendous. :D

Just a thought. As Jake said over on his forum, a group working together can accomplish much more faster than individuals. I plan on posting this over on Jakes forum and Shoptalkforums and see what ideas and talk can be generated.

Kelly (Cohibra45)
Wally
January 12th 2008, 16:41
http://www.keversite.nl/fotoalbum/fotos/63527.jpg

Its for a motorcycle (1500cc) and was showed in England at Birmingham show.
Bad bug
January 12th 2008, 19:16
I would really like to see someone finish one of these projects soon and test the heads.
Bugat5speed
February 7th 2008, 15:51
Hi,

had the first heads on the mill now. Attached some impressions.

Martin

Bug @ 5-Speed
Bad bug
February 7th 2008, 17:23
Martin Good day,

Can your heads fit an engine of 103mm bore.
Bugat5speed
February 8th 2008, 05:13
Hi,

at the moment we are heading to a maximum of 98 mm bore, but the heads can be adjusted later. As the effect of power is much higher than with a 2-valve engine we will go for a maximum of 2.500 cc for the moment. Similiar engines (OHC, or DOHC) with only 2 valves gave more than 100 PS per 1.000 cc capacity. If itīs only 100 then the "small" 2.5 litre engine will give easy 250 PS.
Letīs see!

Next week a test on the flowbench will be done.

Martin

Bug @ 5-Speed
Bugat5speed
February 9th 2008, 14:45
By some mails I found out that there seem to be some missunderstandings on the heads and the engine. The engine will be a complete new engine. Itīs no type IV. We will have a crankshaft with 5 bearings and a very stabile crankcase. So high revvs will make no problem at all. The heads will not fit a type IV, as I didnīt want to follow the type IV-route. Itīs my personal opinion, that the type IV-engines are already over their limits and do not stand what is promised. My experience is that they are not stabile enough from the crankīs side and by this can not stand the "tortures" for a longer period.