Timing???

When I first got the thing running I had it timed at 15BTDC I noticed it had a pretty bad ping around 1800rpm. There is such a range (4-16BTDC) of what you are supposed to have it set at on the internet and all my haynes books says to look at the emissions sticker which does me no good at all.

So I figure I have it way off, some places say around 6BTDC, so I set it there since it was a pretty low performance engine. Then it diesels like a locomotive when I shut it off and can barely get out of its own way. So I more or less split the difference and set it at 10BTDC. It dieseled much less often and less severe.

Ok, now we are going in the right direction, set it at 11 degrees... now that I got new tires on it and feel comfortable driving it at high speed again it is pinging again in about the same place although not as bad as before. No diesel and it drove nice. If I keep it around town it is fine.

Vacuum advance is unhooked when I am setting it, '87 non HO roller with E6 heads, Weiand Stealth intake, Edelbrock 500 4bbl, duraspark ignition.

Would the vacuum advance be advancing too much? If so aside from sticking an allen wrench in the hole how do you know where to set it to?

Try setting the timing @ 13 degrees and not using the vacuum advance.

Pete

Is the harmonic balancer in good shape. Sometimes the outside ring will spin and the timing will not be set right.

The E6 heads like less advance than other SBF heads. Set it at 8-10* BTC and if it pings, mix some premium fuel in with the gas you're using. Midgrade gas is simply a mixture of premium and regular fuel. 89 is a 35/65 mixture of 93/87 or 38/62 of 91 and 87. The hot weather increases your octane requirements too.

The best way to time a 302 is to advance it until it pings and slowly back off on the timing where it almost pings. Hook the advance to manifold vacuum and time it until it pings at medium/high speed with your foot to the floor then back of on the timing 1 degree at a time until it dont ping. Then set the idle air for the highest rpm or vacuum pressure and check the timing again. The good thing about a 302 is you can hear the ping you want max advance without the ping.

Every time you adjust the timing you need to check the idle air adjustment also.

v-8power said:

Is the harmonic balancer in good shape. Sometimes the outside ring will spin and the timing will not be set right.

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I thought about that so I put a new one in it, no change.

baddad457 said:

The E6 heads like less advance than other SBF heads. Set it at 8-10* BTC and if it pings, mix some premium fuel in with the gas you're using. Midgrade gas is simply a mixture of premium and regular fuel. 89 is a 35/65 mixture of 93/87 or 38/62 of 91 and 87. The hot weather increases your octane requirements too.

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6 and 10 degrees and it diesels when I shut it off. I tried running straight premium... it didn't help the pinging much.

I normally run 87 because it is straight gas. The night I had it out was in the mid 70's so it wasn't even all that warm.

I even tried to seafoam it thinking maybe granny coked up her Crown Vic putting around town... again no change.

And yeah, I reset the idle mix and idle after each tinker session.

All I am coming up with is the thing is severly carboned up or the vacuum advance is goofing up on me. I haven't checked the compression yet, but I would think it would have to be really bad to ping on 91 octane.

The vacuum advance only counts for 10 degrees you say it pings at 15 degrees slowly back off from there until it stops pinging under a load. How well is the mechanical advance doing put your light on it and see how far it advances at 3000 rpm you want total advance around 38 degrees but to preset the timing disconnect the advance vacuum line and plug it then set the timing at around 12 degrees. then connect the advance on manifold vacuum and set the idle air for max rpm. with the advance connected at an idle the timing should be around 22 degrees. Rev it up to about 3000 rpm you can guess where about 38 degrees is. Have you checked the timing chain. pull the dizzy cap and with a socket or wrench turn the crank a little clockwise until the rotor moves then turn it counter clockwise until it moves backwards. You can mark the damper to tell you how much slop is in the chain but it should be very little a couple of degrees. Unless the engine is completly rebuilt the timing marks are just for reference all ford V-8s run best on max possible advance and that changes with modifications. All of your high performance ignition systems, carburators tell you to set your timing at maximum advance without the ping. What your trying to do is syncronize timing advance with fuel delivery. Try it with the advance ported or on maniflod vac. Eventually you will find the sweet spot but start with base settings idle air out 2 1/2 turns from lightly seated position time it at 12 degrees with the advance disconnected and plugged. Connect the advance and see if it pings and go from there taking notes for future reference. But yea check the timing chain if you havent.

85_Ranger4x4 said:

I thought about that so I put a new one in it, no change.



6 and 10 degrees and it diesels when I shut it off. I tried running straight premium... it didn't help the pinging much.

I normally run 87 because it is straight gas. The night I had it out was in the mid 70's so it wasn't even all that warm.

I even tried to seafoam it thinking maybe granny coked up her Crown Vic putting around town... again no change.

And yeah, I reset the idle mix and idle after each tinker session.

All I am coming up with is the thing is severly carboned up or the vacuum advance is goofing up on me. I haven't checked the compression yet, but I would think it would have to be really bad to ping on 91 octane.

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Could also be your A/F mixture is too lean. Vacuum advance is easy to check, just suck on the hose while watching the breaker plate in the distributor for movement. Not all 87 is staight(conventional) gas now. Most of what you buy is 84 octane mixed with ethanol(which brings the octane up to 87). Some of the offbrand stations (like the bulk plant I work for) are still selling conventional 87 (no ethanol) but it's made now by mixing that same 84 mixed with 91 to bring the octane up. All the major branded gas is an ethanol mix.

I put a new Cloyes double roller timing set in it before I put the engine in the truck. The original nylon one was completely shot.

I didn't know if my dizzy wasn't set right, like instead of pulling the 10 degrees vacuum advance it was supposed to it was doing 15. It is a rebuilt one that was fresh from the store right before I put the engne in.

Thanks for the advice and what to check and how, I really couldn't find that anywhere else on the 'net.

baddad457 said:

Could also be your A/F mixture is too lean. Vacuum advance is easy to check, just suck on the hose while watching the breaker plate in the distributor for movement. Not all 87 is staight(conventional) gas now. Most of what you buy is 84 octane mixed with ethanol(which brings the octane up to 87). Some of the offbrand stations (like the bulk plant I work for) are still selling conventional 87 (no ethanol) but it's made now by mixing that same 84 mixed with 91 to bring the octane up. All the major branded gas is an ethanol mix.

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Only 89 is marked as having ethonal (E10), once in awhile 87 makes me wonder but in stuff that is picky with it (like my tractors with 6.5:1 compression new) it causes much less problems. For some reason they don't like it when the ethonal seperates out and they have to try to run on pure alchohol. :

Trust me, ALL major branded 87 is now an E10-E15 blend now. Only the off branded companies can still get conventional 87, but not all do. I haul the stuff straight off the loading racks. The stations that do sell conventional 87 usually post a sign out front that their gas has no alkyhol in it. We sell conventional 89 and 91 too, actually I like the 87 better now, as it's got premium in it to bring it up to 87. My Ranger pinged in summer with 87, but instead of running 89, I'd just pour 5 gallons on premium in it to bring the octane up every two tanks or so.

what kind of dizzy do you have in it I was at the part store looking for a cap and rotor for a boat motor and the parts guy brought out one of these for a GM 5.0.
http://cgi.ebay.com/ebaymotors/FORD...r_Truck_Parts_Accessories&hash=item2c5d17e124
Does anyone know how well they work all it takes is one wire key on hot and you can adjust the amount of advance. I think he said they cost about $90 at oreilleys.

Have you tried setting the timing by reading the plugs.
http://www.4secondsflat.com/Spark_plug_reading.html

Just out of curiosity what is the advantage to hooking the vac. adv. up to intake port over the carb?

v-8power said:

Just out of curiosity what is the advantage to hooking the vac. adv. up to intake port over the carb?

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If you hook it straight up to full manifold vacuum, the vacuum advance goes "all in" the second you hook it up and start the engine. You then have to dial back the initial timing via moving the distributor to compensate for that, otherwise it'll never idle slow enough. There's really no advantage I can see to doing this.