318 ign. setting

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plymman

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Hi Guys. Anyone have experience with setting ignition timing? 318 two barrel auto in a 69 barracuda coupe. Previous owner said to use premium gas to prevent knocking. Thought that strange advice for this type of engine,but. When we got home after 700 miles, tried a timing light and got 2 degrees retarded. Emission sticker says zero degrees adv.Now running 8 degrees. Anyone got experience on setting for regular grade? Don't know if I could hear a knock if it was set too far adv....thanks.
 
Honestly, I put them where they run the best. Usually that means advancing it a couple of degrees, or more. That will usually gain you all the way around performance. Also, maybe try unplugging the vacuum advance and see how it reacts. You might want to check to see if the "heat riser" or "the round thing" on the passenger manifold moves freely. I've seen more than once were these rust shut, causing poor performance, poor gas mileage and clatter.
 
My '68 318 runs fine on 87 octane and likes about 40 degrees total advance. Might want to make sure the carb is adjusted right and then adjust the timing. I wouldn't go by what the emissions sticker says. Engines like what they like.
 
I would set it at least 10° for starters. Sounds like you may need to tune in the advance both the mechanical and vacuum and also check total advance @ 2000 rpm or so. I can't tell you all you need to know in a paragraph but there are many good threads about this here at FABO. Use the search function and ask about distributor recurving or distributor advance. Welcome! toolmanmike
 
Thanks for the info guys. Just a bit puzzled by the original advice and the tuning sticker which I realize was for emission purposes. Will start at 10 degrees and then see what the total is. Going from minus 2 to plus 8 degrees made a big diff.
 
You'll hear it pinging if it does. I'd set the initial at 10 (I'd prefer 15 for this app but we gotta find the source of the pinging problem first) on ported (what is your idle speed/still on ported?) with vac line capped to set it & drive it & see if it pings (it shouldn't but...). when you have the initial finalized you'd ideally want to shorten the slots to achieve 35 total (initial+slots) which if you make a mark 2&7/32" CW from the TDC slit that is 35 if you dont have a dialback. See what springs are in the dist. For spot on you (1) set initial with vac gauge method (my preference) (2) shorten slots to get 35 (SB) & that is initial+slots then (3) swap springs so you are just under the pinging point at WOT up thru the gears on your hottest/driest (most likely to ping) day then (4) plug in/adj the vac can & CCW with a 3/32" allen wrench slows the curve & you want to stay just under the pinging point in everyday driving under varying load (in hg) conditions on your hottest/driest day. alot of work but alot of gain to be had. #1 with your low comp/retarded timing it should NOT be pinging even with regular. We gotta get to the bottom of that first
 
Thanks for the info. No pinging since we got the car, just going by what the previous owner said and the 2 degree retard setting. Maybe he had some real crummy fuel in his part of the country? It baffled me what he said. Have a stock 318 in my 52 coupe and it thrives on regular gas.
 
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