I was wanting to play around with a few old motors with their port timing and modify the shapes and sizes of the ports etc. What type of load would i need to connect to the test motor so i don't snap the crank or blow it up. If anyone has one or have pic's of one can you pass them on as i would like to make my own nitro motor break-in bench.

Thanks, brad.

put it in a car or buy an engine dyno

Unfortunately i don't have a car just lying around that i can just throw a spare motor into, I like to keep my race vehicles left alone. I was trying to get away with it without spending any money so if i could knock one up that would be great. When i've seen photo's of dyno's they look like the crank's are connected to some type of large fly wheel or something, what do dyno's consist of anyway?

Basically a large flywheel, a fuel tank, sensors, and software. Not for continuous running, just short pulls.

Break in bench just uses a prop.

"Prop"?? Like a aeroplane prop, obviously a small one?

Yes, airplane prop.

try to use a old fram from a on road car and then get a prop and bolt it to the crank also dont for get the tin foil to krrp heat in i saw this done at the track some just used there old fram from one of threr cars

That's an idea, i have a couple of old chassis lying around. Would it matter if i bolted in a .21 motor onto a 1/10 sized chassis????.........It should be ok ay?

yes it should be ok if you have too drill ew holes and also if you have a spar old gas tank bolt it up to the chassie somewhere and then take a 2x4 board and screw down the chassie to it so you have clearence from the ground .. pm me if you have any other ? that i can try to answer

Do you need anything to control the throttle or do you just do it by hand??

Thanks for this mate it's great info for my little project

just use a old servo just to hold the carb open so you can get it to idle and hold a rev so you can build heat that is what i did

the servo does not have o work just make sure that it will hold the carb open

I would stay away from props for full power runs.
You would need a pretty big one to put a realistic
load on the motor and it would probably fly apart
because of the RPM. A ducted fan would be a much
better choice.