Author Topic: Super Rocket ignition timing  (Read 191 times)

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robin smith

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Super Rocket ignition timing
« on: 05 September, 2017, 09:05:38 »
I was recently in discussion with a well-known magneto restorer on the subject of Super Rocket ignition timing. He suggest 3/8 or even 7/16 BTDC would be possibly more appropriate with modern fuel, as apposed to the 5/16normally applied by myself.

I would be interested to know your views regarding this subject  

STAR TWIN

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Re: Super Rocket ignition timing
« Reply #1 on: 05 September, 2017, 10:19:18 »
3/8" is the book setting. However, modern fuels are lower octane (they even changed the method of calculating octane ratings possibly to disguise the drop) so I would suggest 5/16" would be more appropriate. The one thing you should avoid is over-advancing the ignition timing. That way pinking and detonation lie. Don't know why you were advised 7/16". Seems quite wrong to me.

JulianS

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Re: Super Rocket ignition timing
« Reply #2 on: 05 September, 2017, 13:17:44 »
I use 34 degrees BTDC on the most advanced cylinder with high comp pistons. Other cylinder is 33 degrees BTDC. Runs and starts fine on  that.
« Last Edit: 05 September, 2017, 13:24:20 by JulianS »