timing question

[351w fastback]

i just checked my timing on my car because at about 3500 it starts to hesitate or kinda miss... i checked it and it said it was on 30 degrees when it was idling? i know that isnt right so what could have gone wrong for it to show that? if it really was 30 degrees it wouldnt even start would it? i know i have a small vacuum leak cuz my intake leads oil in the front but what else could it be?
thanks

 

[351w fastback]

anybody?

 

[6Stang7]

timing marker could be wrong I suppose. I remember there being a thread where some guy had an insane timing setting like yours. I forget what it turned out to be. Once you get the reading right, I check your overall advancement.

 

[D.Hearne]

Just because your intake leaks oil in the front doesn't mean you've got a vacuum leak too. Reset the timing back to around 8-12 degrees.

 

[351w fastback]

i reset my timing to 12 and then test drove it and it didnt have any power and it would stumble and backfire a little bit. so i tried moving the timing each way until it got better. when the balancer is on tdc the #1 piston is on top.

 

[WORTH]

Couple of quick notes, make sure she doesn't have full vacuum at idle,(may be on the wrong port)

And #1 is on the right bank as your sitting in the car. (if you were on #5 you'd be 30 degrees off.)

 

[351w fastback]

Yeah we checked the right side. could the distributor be a tooth off?

 

[WORTH]

Yeah we checked the right side. could the distributor be a tooth off?

it doesn't matter what tooth the distributor is on if you can adjust the timing to the correct #. The only time you'd have to skip a tooth is if you couldn't turn the distributor enough to get your setting correct.

 

[Ozsum2]

Sounds like the pointer is off. Just set it (without a timing light) (my preferred method) to where it runs and starts the best.

 

[351w fastback]

what else could it be? valve timing? anything else?

 

[Max Power]

Maybe the chain hopped a tooth and the ignition timing is making up for it?

 

[351w fastback]

well i set my timing at 14 degrees and hooked up a vacuum gauge and it bounces really fast between about 13 and 7 and when i increase the rpms it goes up to the normal reading. could this be a vacuum leak?

 

[6Stang7]

well i set my timing at 14 degrees and hooked up a vacuum gauge and it bounces really fast between about 13 and 7 and when i increase the rpms it goes up to the normal reading. could this be a vacuum leak?

Well, what kind of cam do you have? High valve overlap cams have erratic vacuum at idle. What kind of carb do you have?

 

[351w fastback]

i have a 750 holley and a comp cams xe 274h.

 

[6Stang7]

Ok, cause I know of edelbrocks, they have two vacuum ports, and one has vacuum at idle and the other doesn't You want your vacuum advance to be in the port with no idle, so if you had it in the other, you'd have a righter timing reading. Does anyone know if holleys are like this?

 

[D.Hearne]

On a Holley, the vacuum port for the distributor is the one on the side of the main metering block.