conversion engine for chipmunk
 

hey, im planning out a scratch build of a chipmunk that has a 80" wingspan, and i would like to run an electronic igniton in order to keep wieght down. what engine would be suitable for this plane? i would like it to be able to do aerobatics (not 3D, but good vertical would be preferable). i was thinking of using a homelite 33cc engine b/c ive heard they're quite powerful.
Is there any other engine i should consider?
thx,
andrew

RE: conversion engine for chipmunk
 

Andrew,
A chipmunk at 80" span would have about 7.5 square feet of wing and weight 11 to 12 lbs@ 25oz./sq ft. A 33 powerstroke would fly it fine, but a 45 or 46 would do better. CH has parts to convert to EI for both Poulan and Homelite. The extra power would be useful if the wing loading is higher.

Dave

RE: conversion engine for chipmunk
 

ok, in your opinion, which is better: homelite or poulan?
as far as ease of conversion, that really doesnt bother me much, although i would like to purchase minimal parts in order to use the engine

RE: conversion engine for chipmunk
 

Both Homelite and Poulan are good. Poulan may be more easy to convert. But get more opinions if you can. Capt,n;)

RE: conversion engine for chipmunk
 

ill do a few more searches on here. Ive ordered a rebuild kit for my ryobi from a guy that runs a small engine shop....maybe he will have something that i can use.
i had another shop that i went to for parts, and now when im looking for an engine or carb, he always asks whats wrong with the first engine i got from him. i tell him each time i check to see if any used are around that its for a different airplane. it seems that he doesnt believe me and he is starting to be less help to me, so i dont go there anymore........Hell, after tinkering on my ryobi and reading posts here, im getting a little better knowlege of these engines than he does!

Almost forgot! where do you guys get your carbs for these engines? ive only got a Walbro WT149A for my ryobi and need a bigger one! (this one is only 20/64) does anyone here have a used one they could sell to me? Both shops around here are WAY overpriced and its hard to find anything used around here. I thought about running a wanted ad in the paper, but that might be a little desprate:)

RE: conversion engine for chipmunk
 

Andrew,
Poulan Pro is the best quality. Homelite 33cc and 45cc with the black cover are the easiest to convert, because of the bolt on carb. I found good deals on carbs on Ebay, but you need to do your homework and be knowledgable about types and sizes.

Dave

RE: conversion engine for chipmunk
 

i checked out ebay, and there were a few, but im afraid of the condition of the carbs