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Discussion Starter #1
I have a 1985 Mustang GT with a 1990 302 H.O. engine, edelbrock carburetor and edelbrock intake.

I just did a whole write up and lost it so I'll keep this simple.

Under the factory hood it says "Timing is 12 degrees BTDC at 800 RPMs max" yet everyone on here says 10 degrees and seen with 500 RPMs.
Which should I go with? I know everyone likes to add a few degrees, but for Initial Factory, should I go with the 12 degrees like it says on the hood or 10? I'm going to just run my vacuum advance from the timed vacuum on my carb.

Also, I think my dizzy is 90 degrees off (re-wired) from when I swapped the motor, not sure what actions I took, I did it 10 years ago and it hasn't been driven much since. My vacuum advance is straight toward the front instead of toward the A/C pump. Should it be toward the A/C? :headscratch: Wires are easy to re-wire so its not an issue to do it.
Any help would be greatly appreciated!
Thank you,
Louis
 

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the 10 degrees at 500 is for later models w/fuel injection. i would start with the 12 degrees yours recomends. you can always move it up or down as needed.
 

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Tune it like you would from the factory, so if it calls for 12 then go with 12.

If the engine is running properly and you have enough adjustment room to set the timing, you don't have to mess with it.
 

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Discussion Starter #4
Thank you for the responses.

The reason I was asking the question was since the motor is a 1990 motor (complete aside from intake) would I need to go with the 10° because of internals or if 12° was good because I have the carb setup.

Any idea on the distributor? I'm probably going to move it and re-wire the wires if no one has an idea about it.
Thanks again
 

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Thanks RLG, that is what I was leaning towards because of the whole '90 issue. I appreciate the information!
 

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Discussion Starter #7
Ok... With the vacuum advance pull from the carb and blocked off, I set initial to 10° and it was rough. Set if to 12° ran smoother. Set to 14° even better.
When I first went to adjust it I threw it up to around 18-20° and it ran good then (obviously not under load so no pinging).
NOW... What should it read when I put hte vacuum advance back on? Also, I know from searching, people have different opinions, but should I keep it on the timed port of my edelbrock or to manifold vcuum? I'm not using the vacuum tree that the stock setup uses (although I may since it keeps it from getting to hot).

So I need to know where I should go from here, as I will not be putting it under load for some time and I just want to start tuning the carb again!
 

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Discussion Starter #8
I missed some things in my last post. I think I set it at 12° initial and when I have the vacuum advance hooked to the timed vacuum port on my edelbrock, it reads at 12° since it is at idle. When I rev it a little the timing goes up to about 30° advanced.

Does this sound like a good setting? Sorry for stupid questions, as I do know about these things, I have never experimented with them. Is 12° at idle a good setting with the vacuum advanced hooked up since it does shoot up when vacuum is increased? Is 30° to much for it? As stated before, my factory setting in the vehicle calls for 12° and it idles better at 12 than 10.

Sorry for so many questions, I just don't want to be getting 4 MPG again!!!
 

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You should be fine. Test drive it an see. Im not to familiar with vac adavance, but on a EFI car the timing increases a little more at idle once the SPOUT is in. But the same applies(kinda), Timing is kind of a Set and test procedure, But if it runs good at 12° then leave it.
 

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Discussion Starter #10
Can't test drive it yet, I'm taking my time for once and going to try and get it good to go before registering and driving it. Besides that, it's off the ground on jack stands while I restore the body. As you can see the door in my avatar was complete junk from the kid who did the botched body work before I got it
 

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The vac' will give you between 10 and 20 deg' but is sometimes adjustable to tune.

I would leave the vac plugged for the moment and try the total timing ... total = initial + centrifigual, this needs to be around 34-36 degrees max and should be all in at around 3000rpm.

I have never had to play around with adjusting the vac advance.

IMO i would use the timed port on the carb as this is where mine works best, mine is the 5.0 ford racing crate + Performer RPM and 1405 Edlebrock 600CFM

Steve
 

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Discussion Starter #12
Thanks Steve.

That's the way I was going (timed port), I have a performer carb, 1406, and intake and it seems nice now that I touched initial timing up a little. I think it was actually firing a little late. I didn't have the stator lined up exactly with the armature when #1 cylinder was TDC (engine off)... Come to think of it, I think last year when I was checking the timing it was set to TDC. HAHA I shouldn't have been drinking that day, maybe I would have caught onto it. That explains why the rough idle and 4 MPG!!! It's been sitting for 10 years so I must have done it when I put the motor in back when I was 20...

One problem I did have with the carb was intake backfire, well not with a flame or anything. I was also plugging fuel lines and **** when I gave it throttle after idle for a while, so I may have stopped an intake vacuum leak while doing that... I then adjusted the Pump Drive Link and it seems good to go now. Funny thing is I thought it was getting to much and now that I think about it, I think I went the opposite way than what I wanted to and got a good result. HA HA.

Oh, initial timing was set to 12 with the vacuum plugged and around 3000 rpm its around 30 somewhere, not sure right now, but I think its all good now. I didn't touch the car today, but tomorrow I probably will and I think I'll just try to tune the carb from this point out and rip out all other vaccum (aside from heater controls and brakes) and wires nto needed.
Thank you everyone!
 

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Discussion Starter #13
Thanks Steve.

... One problem I did have with the carb was intake backfire, well not with a flame or anything. I was also plugging fuel lines and **** when I gave it throttle after idle for a while, so I may have stopped an intake vacuum leak while doing that... I then adjusted the Pump Drive Link and it seems good to go now...

I just noticed I put FUEL lines, I meant I was pugging VACUUM lines.
 
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