[Grayguy]

So, I went to set my timing in hopes to fix the backfiring, and I discovered that we some how forgot to put a needle thing on so we could read the timing. So, the question is, how do I set my timing with out one, or do I have to tear it apart and put one in?

 

[ram_me84]

well i have never set the timing with a timing light...
i turn the dist till i get a smooth idle then i snug the hold down bolt then i start it up put it in drive and hold the brake and it the gas down , if i get pinging i back it either retarded it alittle or advance it till it was gone under full load . i have done this on every car andd truck i have owned and i have checked myself with the right way and the first time i was 1 degree off sencond time i was 4 degrees advanced which i wanted anyways , it takes time and a good ear to do it this way but becarefull you don't go to far and do major damage ( i have seen it happen to a friend) .

 

[Grayguy]

I was hoping for some vacuum gauge solution, but thanks for the input, I think I value my engine too much for that.

 

[harvester]

if it doesn't ping or spin slow "or back fire" it should be ok ... i havent used a timing light for years. relax....

 

[MudFlap]

What's a timing light?

 

[DDGRC84]

yeah, i've never used a timing light either. you can use a vac guage, you want to set it for the maximum vacuum without it pinging under load.

Jake

 

[Grayguy]

where do I attach the gauge, the Distributor, then plug off the vacuum line?

 

[DDGRC84]

nah, you want to attach the guage to manifold vacuum i believe, and disconnect and plug the vac advance line.

 

[Grayguy]

exactly which one is the manifold vaccum line, and do I plug the distributor and carb ends of the vacuum andvance?

 

[DDGRC84]

you just need to pull the vacuum line off of the distributor and plug it.

manifold vacuum comes from anywhere on the intake manifold, most commonly (and easiest to get to) would be the line to the brake booster.

Jake

 

[Grayguy]

ok, thanks, will do.

 

[Grayguy]

Ok, I set the timing so the vacuum was at 20 at idle, I revved her up and everything seemed right. I listened for a while and decided to take her out for a spin. She ran great, pulled hard when I floored her and didn't backfire once. Thanks to everyone for the help!

 

[Grayguy]

Ok, I set the timing so the vacuum was at 20 at idle, when I started it was at about 15, I revved her up and everything seemed right. I listened for a while and decided to take her out for a spin. She ran great, pulled hard when I floored her and didn't backfire once. Thanks to everyone for the help!

 

[Thanos]

glad i am not the only one who is having this problem! (i love the search function) Since there isnt a timing tab on my 400 the timing light i own is pretty much useless. Here is the part where i get to sound illiterate (or at the very least ignorant). When i adjust the timing, do i want to get a faster idle or slower idle to know i am turning it the right direction? Right now it is backfiring every time i hit the gas, even moderately. and help would be appreciated.

 

[duallycrew]

I can't even see the timing tab on my 440. The radiator hose outlet is in the way. It's there and i can feel it, so i looked at my 383 and measured the marks and made a couple of marks on the 440 to see where the timing was. I check total timing so i just needed to know where 0 was on the tab.

 

[BigT71]

you want the idle smoother, if you have a backfiring problem you will know when you are right on the timing. just did that today. now i am having problems getting the advance set right to prevent detonation. I now have at least 10-15 more Hp than i did before setting the timing, but under load she wants to detonate like crazy. while distributor was out, i replaced the advance weight springs with an mp spring kit and replaced the vaccuum module. do i now need to turn the adjustment on the vaccuum counterclockwise to prevent detonation? Help?

 

[william]

I guess I am the only one here who uses a light? I have set timing "by ear" in a pinch, but I don't like to make a rule of it. Yes, you can get it set pretty well. On a low compression V8 you can get away with it, but on a higher performance engine (high compression, forced induction, etc), I don't think relying on the seat of the pants method is smart.
On my stock 75 440, I set the timing at 11 degrees BTDC. The 75 spec calls for 8 BTDC, and it runs like a dog. The 74 spec calls for 10 BTDC, where it runs better, but 12-12.5 BTDC is good for a performance application (I would run that in a car). I knocked mine back to 11 because I am hauling and using cheap gas, and it also smoothed out the cruise speed performance. This illustrates that the factory recommended setting does not always have best performance/drivability in mind.
A timing light will also tell you if your vac and centrifugal advance curves are working optimally. Get a light (and a degree marker for your engine!), they are well worth the few dollars.
Also, pay attention to the factory degree indicating tabs. Some have holes in them that are set at TDC (0 degrees). If you set your timing light to this hole, your engine will run like crap. Scrape the rust and grease off the tabs so you can read the proper degree markings! Speaking from experience on that one!
william

 

[BigT71]

actually, if i was smart (ask my wife if that'll ever happen) I would probably go out and buy an advance timing light. I actually read an article in Mopar Action (I think) about setting initial (idle) timing at about 5deg btdc and 3000 rpm @ 35deg being a much more accurate way of timing. It was a really good article. Now if anyone can help me with this damn detonation, I would appreciate it. lol

 

[Thanos]

i read that article too. but i think it said 50some (but that might have been for a 318 or something). it was mopar action and the article was written by e-booger himself i do belive. I will see if i can find the article and post what it said.
I got my backfire problem solved. Twisted it so the speed increased and then tweaked down the idle on the carb. VRrrrrrrrrrrrrrooooooooooooommmm i go again. My truck has officially been resseructed from the dead. think it needs new spark plugs ( think the other ones got a little soaked while the truck sat up for the last *cough* 5 months (sucks being poor).
And yes, i own a timing light with the advance dial on the back. it is a great investment (especially when if you happen to have a small block around that is at 18 degrees and the factory markings only go to ten!)
as to the detination problem above someone was having... well.... i really dont know. Never known anyone to have a problem with it, generally it is a backfire problem. what is it doing when it is detonating?

 

[duallycrew]

When you set total timing you need to first determine when your mechanical advance has stopped. When i first checked mine, it had the mopar performance springs in it and it was at full advance by 1400rpm. It was a pain to start and would idle pretty high in park and wouldn't idle worth a damn in drive. I pulled and tweaked the springs a few times until i got full advance at 2800 rpm. Set my timing light at 35 degrees, reved motor past 2800 so it was at full advance, and set the timing marks at zero. Most big blocks like between 34 and 36 degrees total timing. If the motor is detonating, it is either low octane gas or the timing is too far advanced.