Engine Size Calculation & Carb Opinion

Bought an engine that i have been running for about a year. Unsure of a few things and looking for some answers from the experts

Not overly tech inclined

Need to know what capacity my engine is. Specs below

92mm barrels
82mm stroker crank

Next question. Based on the details below that were given to me when i bought the engine are 40mm twin DCN's the right carbies for these stats?

And the last question. What sort of HP do you think this engine should make?

Complete engine stats below

92mm barrels
82mm chrome moly stroker crank by Scat
camshaft & gear
cam followers
type 3 fuel pump
30mm Mellings oil pump
200mm pressure & clutch plates
2 x 40 DCN Webbers
chrome moly push rods
2 x 3 bolt Webber inlet manifolds
swivel foot rockers
heavy duty single valve springs & seats
40mm stainless steel intake valves
35mm stainless steel exhaust valves
port & polished heads
10lb flywheel
std pushrod tubes

Thanks in advance for the help. Awesome as usual

[ Edited on 7-5-2007 by sewelly62 ]

Engine is 2180.4cc

Power will depend on a lot of variables in the heads and cam and compression ratio,
but with those carbs(what venturi?) I woulds say that 100 to 120hp at the tyres
with massive torque would be a guess.

unsure of what cam it is it is fairly mild and really rideable. The engine is in a trike.

Really turns on the bulk of its power at around 2200 revs onwards. Currently running stock 1600 cannon mufflers which are restricting exhaust exits. Having a new exhaust built tuned length at the moment that should be ready by the weekend and that should hopefully help it breathe a lot better and i'm told will give it more bottom end.

Unsure of the venturi size. Anyone have suggestions on what they should be?

Here is one school of thought

http://www.carburetorclinic.com/tuning_the_weber_idf_carburetor.htm

Venturi selection - For engines that rev pretty high (6000-7000 rpm), you are best off choosing vents that are about 2 to 4mm smaller than your intake valve size.

For engines that are set up for torque, like bus engines, and other torque-happy applications, you can go a little smaller on the vents and get better low end response. For these, I'd recommend 4 to 6mm smaller than your intake valve size.

So what happens if your vents are too big? You'll have reduced air-speed at low RPMs, which makes tuning harder. Air speed is one of the things that tells your different fuel circuits when to start to come on. It will be soggy down low.

So what happens if your vents are too small? The undersized vents will restrict your engine's ability to breathe at higher RPMs.

How critical is it? Not terribly, but if you're way off it will matter, and you will feel it. Putting 40 vents in a set of 44 IDFs with 40mm intake valves will be pretty soggy down low. Sticking with the 36's would be about right. Putting 28 vents into a set of 40 IDFs on an engine with 40mm intake valves will limit your top end noticeably as well. A set of 44 IDFs, for example, can me made to work on many engine sizes with the standard 36 vents, but you might find that you could optimize them better if you are willing to spend the money and try some different vents that would be ideal for your application.


Aircooled.net reccomend 32's for a 1600 and my experience tells me that is spot on.
Same thought with 36 vents for a 1916

So "my" suggestion would be AT LEAST 36 vents, if not some thing more.

Barry