Mathematics Needed!

[GunMetalGrey]

So some quick notes, I am a high school student that participates in many Eco-Marathon type competitions; most notably being the Shell Eco-Marathon (which I was at a few days ago)
I built a fuel injection system for our 4hp briggs and stratton engine and was never able to load test it or get any real world testing before competition which yielded a disappointing 500 mpg. (winning team left with 3587.1 mpg.)
I have been wanting to build a small engine dyno for quite some time now, and I finally got the okay to start building it, my only problem is figuring out what size flywheel I need to use.
I need to simulate roughly 300lbs of resistance (car with driver weights about that much)
The motor is limited to 5400 rpm's, and I would probably like to gear down the roller that goes against the wheel to the flywheel, so that we could spin the flywheel a bit slower in case anything bad does happen it may not be as bad.
That being said we have awesome local sponsors that have 40 ton lathes and can machine very good quality pieces so that we avoid any quality issues. Steel would most likely be used for the flywheel.

Cliffs:
Making dyno for small engine
Need help figuring out flywheel weight and size

Thanks!

[herbivor]

Hmm, wish I could help you. You may find better luck on this forum.
http://www.eng-tips.com/threadminder.cfm?pid=108
Most of the guys on there are machinists and engineers and would likely know more than your average wrencher.
Do you need to consider aerodynamics in your design?

[Threehz]

Wish my highschool had opportunities like that.

[yberther]

http://www.land-and-sea.com/articles/national_kart_news_the-dynamometer_article.htm

I've used these for 600cc and 450cc motors for tuning and comparative dyno numbers.

[GunMetalGrey]

Aero does not matter too much.
I have looked at the fluid dyno's but those require a lot more things such as cooling and whatnot.
The best part of inertia is that we can replicate our burn-coast style of driving.

Sent from the future. Or my phone, who knows.

[Thizzelle]

fly wheel design was close to the end in mechnical engineer degree.

http://www.ecs.umass.edu/mie/labs/mda/fea/fealib/jiewan/flywheel.htm

gets complicated. I did do a project on sizing one and a pump, but idk where the fuck it is.
search web lots of stuff on it

[GunMetalGrey]

See the problem is that I am still in High School, and the link you just sent me has math wayyy beyond my knowledge area.

[tonerrrr]

http://www.dillingerescapeplan.org/