Confusion on legal engines

[fromnarm]

Hi all,

I have desided on juming into the 1/10 200mm foam class. I have desided on car (serpent 710) the last step is the engine. I have been looking at Rossi engines.

I have read through the BRCA Rules (http://www.brca.org/rules/37%2010th%20IC.pdf) and it states
0.12cu or 2.5cc - thats cool
3 ports - cool again
Front rotary valve?

I have read through a number of threads on engine recomendations and rossi engines recomended(NSR,RER,TSR) have slide carbs. Are they legal? From reading the rules no?

And lastly whats the story with Turbo cranks? They don't seem to apply to the egines I have mentioned as only the 5 port engines use them. Are they legal?

Cheers,

Brett

[Mark Christopher]

read the rules again
200mm is ONLY .12 235mm is .15
not restricted to 3 port (any amount) you can use turbo's etv thats why its called the OPEN class
25% fuel is ok too
if you have above dont turn up to a rubber national though or you WILL be sent home!!
3 port engines do have turbo
rotary valve is not the carb you may use slide or other (slide is best)

[Yokman]

For 200 class you are limited to a 2.1cc or .12 cubic inch engine (both the same just European and American way of measuring engine size). For 235 class its 2.5cc or .15 cubic inch and for 1/8th scale it's 3.5cc or .21 cubic inch.

The rotary valve thing is the way fuel is introduced into the engine via a slot in the crankshaft and then through the hole in the crankshaft to the crankcase. You're confusing this with rotary and slide carburetors. Slide carbs are the norm for racing engines.

For the rubber class engines are restricted to 3 ports (two transfers and one exhaust), 5.5mm carburettor bore and 5.2mm exhaust outlet. The crankshaft hole is restricted to 7mm with a max 0.5mm chamfer at the crankcase end and a turbo scoop is allowed provided it doesn't intrude into the crankshaft hole. You can only use up to 16% nitro fuel. Turbo plugs are allowed.

For the foam or outlaw class the only restrictions are that the engine must be 2.1cc/.12 cubic inch and the noise it makes must be below a certain decibel limit (it's in the handbook can't remember what it is) and you can use up to 25% nitro fuel. So, in outlaw class you can use any size carb bore, you can have any number of ports (5,7,8 etc), you can have any size exhaust outlet provided your engine stays within the noise limits, and the 7mm crankshaft hole and turbo scoop limitations are removed.

Effectively, in foam/outlaw class you are unlimited to engine tuning but remember you still need to be able to run for 5 minutes on your 75cc tank of fuel. There's no point in having an engine that will run 50,000 rpm and produce 3 hp if it'll only last 3 or 4 minutes on a tank of fuel.

I've run in the foam class with my 3 port rubber class engine and all I do is fit a 6mm carb, 5.5mm exhaust and use 25% fuel and I've never felt down on speed or power.

Hope this helps.

[fromnarm]

Cool, the feedback has been helpful :o

Joys of being a new to it getting the terminology wrong :eek:

Looks like I will go down the 3 port route and follow your suggestion