BBCLiberator

iTrader: (2)

Just curious for those of you running a DUI marine ignition with mechanical advance, what are you setting your base timing at?

I have a mild 502 with iron heads and am curious what you guys are running with a similar set-up. I run 91 octane ethanol free fuel.

Let me know what you think.

picklenjim

Assuming you mean your timing at idle? This isn't the way you should be setting your timing. What is important is where it is at full advance. Timing should always be set with the engine revved up to about 3500 rpm. In your case that should be all in at 34-36 degrees. Where ever it falls at idle then should be fine as long as it's 10 or more degrees. Even if you know how much advance is "supposed" to be in your distributor I wouldn't depend on setting it at idle. If your balancer isn't marked up that high in degrees you will need to get a timing tape to put on it. You want to know that it is correct when running on the top end. If you set it at idle you are just assuming it is correct on top end. As said the idle timing isn't that big of deal, however you will find with a hotter build more timing at idle will give you a cleaner burning, crisper idle.

getrdunn

iTrader: (7)

Exactly. I need to change mine up a bit however going to wait til water tuning. Mine are currently set up fully advanced @ 4,500.

With that said just pay attention and also if you have tune kit it will or should have illustrations etc. if your not sure and need to figure out what you have post a pic of or google it to find out what you have currently. Different color springs and weights.

SB

iTrader: (1)

What's mild ?

BBCLiberator

iTrader: (2)

I agree for full timing, I get full advance at 3800 or so but test just over 4. If I go above 12 degrees is get a little hard to cold start. Full advance I see about 34, but I'd like to see 36.

Engine is a 92' mag converted to full roller and scorpion rockers, Madera cam, SM manifolds, edelbrock air gap with 850 Holley and about .5 compression bump. Stock internals, stock head with mild clean-up, valve job, and hp500 size exhaust valves.

Choke works fine, I have just never seen a few degree bump make so much difference before for starting. I see about 22 Degrees of advance which is what they advertise, 22-24.

Edit: at 10 degree base timing the thing hardly turns over before it fires. I prime with three quick full throttle pumps, which is what I've always done. At 12-14 degrees it cranks over 5-8 times so it isn't bad, but I find it hard to believe that out of 2-4 degrees of timing...

SB

iTrader: (1)

12-16 would be typical. Yes, 2* can make a huge difference with some motors, squat with others.

Your motor will tell you what it wants. (Darrin Morgan quote)

getrdunn

iTrader: (7)

Kinda like the ol pot heads in high school telling you how to set your timing by holding the brakes to the floor and press the gas pedal while turning the distributor. When the tires brake loose - tighten er down. Wtf. Puff puff give. Life's a garden dig it. (Joe Dirt quote)

SB

iTrader: (1)

College I had a 8" ATI 4500 stall converter, big block,big solid cam. Set my timing and adjusted carb in park. Got in car, put in drive, carb needed a little more idle tuning. Car didn't creep forward because of converter and aimed slightly up hill. Cool !

I left in Drive and walked to engine, played carb and with vac advance setting
adjustable) and hooked to full manifold vacuum. Cleaned idle up in drive. Some time passed and obviously I forgot it was still in drive. While leaning over the front, I 'whacked' the throttle. Car jumped forward, I was up in engine compartment and rolled out of side. I dove in thru open window and got my hand on the brake inches before a tree and ditch. No one saw. No cell phones and vid cameras back then - thank god !. So all I had was a story when I was willing to tell it.

I was not smoking weed but I'm pretty sure I did later that night !

I should have been up for dumbest but most athletic achievement ever ! LOL.

getrdunn

iTrader: (7)

That is awesome. Did you have a mullet? Just wondering? Imagine nowadays your chit would be all over the net/YouTube from whacked out kids doing selfies woulda busted you. Btw - Tune in the park. That's bad azz and too cool. I forgot karma was quick back then also.

SB

iTrader: (1)

Worse than a mullet.. People (adults, strangers even) would ask me what I had against society. Hah !

Uust before working in a garage, Restaurant I worked at that summer (kitchen help) payed me $50 cash (each time) to remove a person or people that where causing too much trouble at the bar or etc. I never had to touch a person all summer, other than , well, I better not type that out in public just in case.

No videos. Great stories !