Hello EVERY. sorry in advance if this post is long.

I am a engineering Junior from the Univ of Arizona. I am in SAE, automotive engineering club, and we build a formula 1 style raccar and compete in a competition in Detriot every year against 145 other engineering teams from accross the world. ( ref http://www.sae.org/students/formula.htm). The competitin has many rules......about 140 pages.....but some of them are 4 storke engines only, and you must run one 20 mm restrictor that all air must pass through, engine has to be 610 cc or less, no nos or power adders. Most cars weight 450-500 lbs, and most teams run turbo or super charged 600 cc street bike engines, computer controlled fuel injection, and with restricor make about 60-70 hp. These engines weight about 100 lbs.

I am thinking about next years car, and thinking ATV engine. It must be 4 stroke, I want light weight, carbed, electic start, air cooled and a dry sump. It has to breath through a 20mm, and must be simpe to tune and make good power. I think with the right setup we could do well with an ATV engine, be the first ever team to do well with a carbed engine, and and engine not from a street bike.

The advantages I see are.......lightweight, relaible, easy to tune, better suited for the restricor, cheaper, and if it is a light car, with somewhat compeditive hp I think it would do well.

The competition induleds driving events like drag, autocross, skidpad, and points for design and cost. I think saving the money of not doing turbo/fuel injection/computer would score in cost, and if we could hold our own in the racing events in terms of power.....

So what enigne or engines would be good.
What could be done to make more power, while staying restricted
has anyone built restriced engines, or modded 300, 400, or 450s.

Any help anyone has would be welcome. I wann show people ATV engines can compete.

Thanks everyone

 

I personally think you are going to get spanked if you try this. And here is the reason why I think it is a bad idea. If you have many pistons you are going to split the intake pulse up into smaller segments. Each little piston will take in very little air with each stroke, but will make big cumulative power.
With a big single thumper, that big piston is going to try and pull all that air through that little 20mm hole in one big gulp.
I personally don't like the air cool idea either. With the air cool deal, you get hot spots and all sorts of weird stuff going on inside of the combustion chamber under high horsepower situations.

If I went up against you, I would size my engine to the max cc's I could make it, with the max amount of pistons to make this amount of cc's. This would probably be a 2 or 4 cylinder engine. Then I would put a "correctly sized turbo" on it and make a ton of intake manifold pressure. It's just a pump so I would jack the pressure sky high to over come that little 20mm hole. The higher I jack the pressure the more volume of air I would get through this thing. I would run somewhere around 30 lbs of boost, if I could put the type of pistons and rods I wanted in it. At 30 psi gauge, I would have an engine that thinks it is 1830 cc's!!!!!! Then I would run alky (maybe a splash of nitro?) to handle this kind of boost.

Do you thing you would have a chance against this type of set-up? The only event you would win in this deal is the cost.

Good luck; I could be wrong, but that's the way I see it...............sorry.

 

hey, I agree with docturbo, and find a way to make the vehicle lighter, like titanium parts. work smarter.