650 '700' kit do it yourself thread....

[spanner]

As far as I can see and tell, the Raptor is also a "dump" design.

OK I see that now,

It looks a lot straighter and with less of a turn into
the combustion chamber, than Husaberg and a shorter divider,
and does not swell out as much on the outside side walls...

 

[bushmechanic]

dumpy swirl tumble ?

http://husaberg.org/mechanical/17723-fiday-night-thread-entertaining-pics-2.html

more links halfway down

 

[spanner]

That looks like a brilliant design, Bushie, but it might cause
complications with the plumbing

 

[bushmechanic]

yes indeed spanner imagine the cam grinds on the radial valves as well LOL

even a 2 valve head can be very respectable when mid rpm torque coupled with fuel efficiency is desired over peak hp ie v8 supercars and brabhams early F1 engines

Nascar History, Chevy and Ford ? Speed Talk

from a previous thread :

the intriguing part relates to the cosworth efforts about 1/2 way down the page.

Running on "pump" gasoline, 1967's Cosworth DFV produced 133hp per liter. Astonishingly, the last Cosworth 3.0-liter, Formula 1 engine, fed comparable fuel and likewise naturally aspirated, produces about twice that! DFV of 1967 set the pattern for the contemporary engine with its "supersquare" (wider than higher) cylinder dimensions, its pent-roof shape combustion chamber, its narrow included valve angle, its four valves per cylinder operated by double overhead camshafts and its clean porting. The DFV was not radically different from previous engines, Its significance was that its detail design took advantage of the potential of four, rather than two valves per cylinder for enhanced breathing and burning - the fundamentals of effective combustion.

broken link to F1 dictionary

Brabhams efforts were before that time and for a 2 valve flat head his engines were incredible.

8W - Who? - Jack Brabham

3 litre repco-brabham BT24 from 1967 engine piccy......you can clearly see the inlet is way off the vertical....I'm guessing about 10 degrees, which would make the valve to inlet angle about 35 degrees.....ish

its a 90 degree V8, bore is 3.5", stroke is 2.375".......power of the last versions was quoted as 325bhp at 8300rpm

only pics I can find of the head are of the brabham slant 4 alloy head fitted to midget racers, what I wanted to show was the round flat roof combustion chambers with 2 valves

and compare to the 4 valve pent roof head of the cosworth

Simple basic design, coupled with shortish stroke and large bore gives reasonable breathing at moderate RPM's, practical for the period.
Parallel valves allow massive overlap with no chance of valves striking each other if they float on a missed shift etc.
Compact minimum area combustion chamber minimises thermal losses and allows good piston design.

Chandler-Curtiss Racing Car - History, Profile, Photos and Information

 

[spanner]

I am rethinking now

Maybe a down draft inlet can be used in the std Husaberg frame, would
mean using the backbone as the airbox again, just weld a new spigot in the appropriate place...DNA air cleaner....fuel injection...

I just need to get a Husaberg head to mate with a 690 head...:unsure:

Wounder if the 690 rockers could be used... and the cam...

 

[Goose916]

Hey Bushie, getting those measurements for you on Sunday. Sorry for the delay.

 

[bushmechanic]

I am rethinking now

Maybe a down draft inlet can be used in the std Husaberg frame, would
mean using the backbone as the airbox again, just weld a new spigot in the appropriate place...DNA air cleaner....fuel injection...

I just need to get a Husaberg head to mate with a 690 head...:unsure:

Wounder if the 690 rockers could be used... and the cam...

good idea spanner there may be more room if you used the rear head of a twin
and ran the intake up near the steering head

exhaust plumbing would get funky though

no worries goose its not urgent

 

[spanner]

Put the head on backwards I guess...

 

[Goose916]

you guys are so out of my league! Still, I secretly want to see this crazy-*** project happen!

 

[Dr_C]

Here is how I look at inlets with a tumble design [emoji1]

 

[spanner]

what is it

 

[Dr_C]

what is it

My head!

 

[spanner]

You can certainly see a bigger window with those ports,
Very nice.

Frightened the .... out of me that did

 

[Dr_C]

I know! The ports are pretty scary too...

 

[berglsmerg]

You can certainly see a bigger window with those ports,
Very nice.

Frightened the .... out of me that did

Uh huh, I was scrolling away on my big screen telephone on my way home from being in a dark smelly h ole in the ground all night and near crapped my dacks when that pic came up. Nice one Mats. Is the texture of the port walls anything to do with creating a boundary layer?