Radial engine question.

B

BRIAN

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A question for the thinkers of the group.

As I understand it, a radial engine has to have different timing for the ignition and valves on No1 Cyl than for the other cylinders on the same bank.
This is achived by altering the cam folower positions for the valves on No1 cyl. And grinding the cam lobe for no1 cyl in the mag slightly different.



WHY? no prizes just a BIG round of applause.

Brian
 
I have built 3 radials to date and am working on #4. I have not had to alter tha lifters or the pushrod on any of them.

"Billy G":))
 
i cant see any reason for it to have any difference in timing?
where did you find this information?
steve
 
We are talking top end performance here, a engine will run without these refinements.

I first was told of this when I worked for a company that made magneto's (SIMMS),

The only other reference I have found was in a paper by a chap named Hartridge who was involved in engine development during WW2.

Now think what is the differance between No 1 and all the rest,

That will get you on the right track.

Brian.
 
The #1 piston is the only one connected directly to the crankshaft via the main connecting rod.The rest are connected to it as slave rods.

"Billy G" :thinking:
 
OK bill you are on track.
How how will that alter the timeing???

brian
 
If you physically alter the timing on one cylinder it will alter the timing on all cylinders. If you physically alter the pushrods on one cylinder it will only open or close the valves differently on that one cylinder. If you alter a lobe in the magneto you will only change the amount of spark at tht one cylinder. You gain nothing but trouble from any of these alterations.

Gotta get back to work cleaning the surface grindr to prep for paint. I will get back to this. You got me hooked. LOL

"Billy G" :thinking:

I can hear you guys thinkin. Yer just waitin for me to solve this one. :nono::nono::nono::lmao:
 
Thanks for prompting the thinkers Bill.
Brian.
 
I don't have an answer to the OP's question, I do recall however my Dad telling me that the machine guns on the fighter planes were timed so as to shoot between the prop blades, I always thought that it was an interesting dilemma.
Bob
 
Hi Bob
A interesting subject But I fear we are wey off the subject of radial engines.

But the problem you mention, was that the best way to line up the guns on WW1 aircraft was to have the guns directly in front of you this ment you fired thro the arc of the prop. not a good idea!!
The first atempts where wedge shape blocks fitted to the rear of the prop to deflect the rounds that hit the prop, Not a good idea.
But a man named Constantinesco invented a interuptor gear that stoped the guns as the prop was passing
Making heros out of the pilots that had this system fitted to there aircraft

Brian
 
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