Ignition Timing

[Ken Watson]

I have a twin carby sport subaru which we have upped the comp on to about 10.4 - 1 and done a good head job and have a gruntier cam. I set the timing at 8deg btdc at 800rpm but believe I could run heaps more advance. Has anyone tried? or what have others set theirs at? Any thoughts welcome. Ken

[birdy]

Just keep upp'n the advance 2* at a time till it 'pings' when you rap the throttle on, then backoff a couple.If it ain't ping'n, it ain't to far advanved.[The bush mechanic cumn outa me now ay.]Ignorance is bliss............but only till you realise you were.Ingratitude stinks.......be generous carefully.

[Tim]

Birdy's bush method is pretty close to the mark as long as you have keen ears for the pinging sounds. (like Willy Nelson at 2 in the morning ay Ozz.It would probably be better to tie the gyro down and run it up to flying RPM's and adjust the timing to 26* to 30* BTDC. That way you are not setting it for a specific batch of fuel. You will have to measure around and mark the flywheel from the existing timing marks because they only go up to 20* BTDC.Tim McClure

[telf]

Hey Woz,Were they playing yee-haa music at the Nats?God help your ears.Hope they recover soon....(this should stir the pot a little)telfFlying - The knack lies in learning how to throw yourself at the ground and miss. (Douglas Adams-The Hitch-Hiker's Guide to the Galaxy)

[birdy]

Willy N??,I thought sum poor bastered woz die'n.Ignorance is bliss............but only till you realise you were.Ingratitude stinks.......be generous carefully.

[Ken Watson]

Thanks all, especially tim. Hunted the web and found what fixed wings use: 38 @ 5000 31 @ 4500 28 @ 3500 12 @ 800This may help some others. Ken

[Des Garvin]

Ken what was the website addres please, Thanks Des

[Tim]

I will pack my Slim Dusty album next time.Tim McClure

[birdy]

And I'll be pack'n a .44 Tim.Ozzy, I'v been meen'n to ask ya, that little corroboree thingy on the sundy arvo, is that wot you was call'n a daisy chopper, or daisy cutter, or chopper chain??.............. hell, I can't think wot ya called it now.Ignorance is bliss............but only till you realise you were.Ingratitude stinks.......be generous carefully.

[Ken Watson]

Des, it was from a few sites.I looked under Ignition Timing Subaru EA81 on Google. Some were direct drive and some were redrive. I think the important one is the 37 @ 5000. Ken

[asra]

If, like me, anyone is hand starting their EA 81 through a reduction it is important to ensure that the centrifugal advance is going back to the idle setting at low revs. Mine became erratic, my right hand is still sore months later.The bob weights must be free on their pivots and the springs must be able to pull them right back to the retard position. I found my springs were stretched. If there is any difficulty getting both full advance and full retard it is possible to file the bob-weights so they come in further for full retard.John.Sorry about that, I was logged in as Llewella.P.S. I've got a beaut Frnkie Lane CD, you know, the one with 'Mule Train' on it. I'm sure you'd like it Oz. Can't wait for Nationals 06!!!

[Des Garvin]

Ken thanks for that Des

[Tim]

Ken, I would not be running over 30* when the engine is at flying RPM's and load. 35* to 37* will surely pre-ignite, unless you are running low compression and a flame retardent (octane booster). In modern EFI engines, much greater advances (60* to 70*) are often used on the engine overrun, off throttle, to aid emission control. If you tie the Gyro down and adjust the timing at flying RPM's you will find no gain over 30* and more often than not, you will start to loose RPM's. How about the Wiggles OZ?Tim McClure

[birdy]

Or ACADAC.Ignorance is bliss............but only till you realise you were.Ingratitude stinks.......be generous carefully.

[Ken Watson]

Thanks Tim. Ken