taco_reaper

I want to do a Nitro conversion on a xray m18.

I have not delt with the micro scale r/c's and want some input if this is even possable.

whats the smallest nitro engine made? could i use an OS wankel/rotary. If i can is there a transmission that handels the high engine revs, but is compact enough?

what are my transmission options? can i get a 2 speed?

these are questions i've been trying to answer, but so far my own research on the internet hasn't gotten very far. thought i'd ask if anyone else has tryed anything like this with any success.

and before anyone asks why i'd want to put a nitro engine in this car that does well with its electric. my answer is because i watched to much home improvment..more power (grunt) (grunt) (grunt)

raykessler

first off im pretty sure a 2 speed is out of the question....
iv never seen an xray first hand.. but you may be able to fit the .12 that comes with the old nitro RS4 in it
or you could look around for an old .10

Kyle2Baseball

the smallest engine can as small as an .049 which is an control line airplane engine

raceme

juss my opinion i think it will be close to impossible if you didnt have the right equipment. cuz if you brake a part you either had to have that custom made or a modified part from somthin else. and if you put a engine in there it looks like it would fit but it would take up half the chassis.

i8tweety

My Feedback: (11)

An aquantance of mine put a norvel engine in a buds 1/18 scale. Some fabricating was required to make it fit. As for the x-ray, being a 4wd car, there's less room available to make things fit. I'd stick to throwing a hotter motor and extra cells. Besides, with nitro you wouldn't be able to run the car on your kitchen floor.

taco_reaper

i was thinking that might be a problem, the 4-wheel drive. but i'd like to give it a try anyhow. just because nobdy has done it yet

i've been looking into this os rotary engine too. not sure if it would be small enough, but if i could fit it it would be grossly over powered :P but it seemes the operating speeds of those rotary engines is up to 18,000 rpm. since they were made to just have a prop bolted on them for planes i doubt i coulkd even use it for a car. finding a trany for 18k rpm probably isn't even possable.

nitromacguyver

Trust me when I say that this is possible. i have also given serious thought to converting a 1/18 electric to nitro. the only problem that i've run into is a lack of nessasary funds ($$$$). when i have time to night i will put up a long post that answers all of your questions.

nitromacguyver

The first thing you need to remember is to keep it as simple as possible.
-This means no 2 speed tranny.
-Also you can remove the center drive shaft to make more room availaiable on the chassis but you would lose the 4WD.

The second thing is don’t use an airplane engine. It will be more work than its worth. And you don’t realize a couple things about them.
-They only run at 18K-22K RPM because of the propeller which puts a constant load on the engine. If they didn’t have to spin the propeller they would probably run at twice that speed (35K-45K RPM).
-Car engines don’t have as much constant load on them at all times, so theycan run at up to 35K RPM and if they didn’t have any load they could even reach up to 45K-55K if they didnt blow up by the time they reached that speed.
-Air plane engines are not designed to run at the speeds that car engines do.

This is why I recommend a .12 size car engine.
1) clutches and other nessasary parts are already available
2) they are designed for the application.
3) the engine wouldn’t blow up.
4) it would be like putting a viper V10 engine in a Toyota Corolla.

the smallest engine availiable is a glow engine for planes made by cox. it is a .01 size engine that is about the size of a quarter.

the only thing that has stopped me from building one is the cost.

you wont need any thing other than a rotary tool (dremel tool), some 2part epoxy and some ingenuity. let me know if you decide to build this, i would be very interested and i could help you with any problems that you come to. good luck!

taco_reaper

i have the xray being express shipped from honk kong. gona look into that .12 engine.

i realy want to keep the 4 wheel drive. gona need all the wheels i can get to put the power down.

what i'm wondering is what servos i should get. i'll need to fit batteries for the servos and a gas tank on the side that is built for the large battery pack.

i'm thinking of getting the kit made for the stock electric m18 but i need a battery for the servos that takes up about a third the space of the standard one used for servos and electric engine.

nitromacguyver

that wont be a problem at all because all the battery needs to drive is the servos not the motor which probably took 95% of what the battery supplied any way just look for battery packs that the airplane guys use in thier park flyers.

you may also want to consider a wheelie bar to keep the car on its wheels and not its lid.

lykan

Here's an idea for you. I know that the airplane engines are about the right size, but like everyone says, they have no throttle they are for control line airplanes, or gliders to get em up.

My idea is to put a decent size flywheel/pulley on the motor to imitate the rotating mass of the prop. You could use belt tension as your throttle/transmission.

So you would use a servo with a roller on it. activating the servo would push the roller against the belt, making enough tension to turn the wheels. This would also alleviate the problem of having gears and etc. breaking.

A lot of lawn mowers/rototillers use the sametype of belt tension system I'm talking about.

So your engine would go fullspeed all the time, only slowing down a bit when tension is applied to the belt.

The belt could go to pulleys on both the front and rear axles making it 4wd

Good luck, keep us apprised of whats going on

378

My Feedback: (4)

gimme a sec to find a .06 that has a carb and would fit rather nicely on one side of the drive shaft like my MT2 engine facing rear and on left side of driveshaft with ustom fuel tank on other side and behind the tank is the electronics

378

My Feedback: (4)

http://www2.towerhobbies.com/cgi-bin...?&I=LXSD22&P=0 and a .09 http://www2.towerhobbies.com/cgi-bin...?&I=LXLW81&P=0 both have carbs both are tiny enuff to fit i even saw someplace someone made a jake brake for the .010

378

My Feedback: (4)

the rotary is bigger than the car .30 the thing wouldnt fit my MT2 and thats a 1/10 mt