Unusual Timing issues - could I have the distributor out 180?

Chythar

Recently finished repairing my rear
Dirt-Old 20+Year Member
Aug 26, 2004
2,370
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Foothill Ranch, CA
I've been trying to figure out my coolant temperature issues recently, and haven't been having any luck. I have a mechanical water temp gauge on the way (Autometer #2333) from Summit, so we'll see what that tells me.

I'm also getting some pinging at the higher RPM's, and I'm running 91 octane (premium in CA). The pinging gets much worse when the fog rolls in at night here on the coast. While I'm waiting for the gauge, I decided to mess with my timing and try to eliminate the pinging. After messing with it, I'm wondering if I didn't set the timing right when I dropped in the distributor. I admit most of my 5.0 knowledge is from reading these forums, I don't have a lot of hands-on work.

The 'Stang will ping:

--At 3000 RPMs when the stock temp gauge is at about "R" or "M"
--At 2250 RPMs at night when the fog has rolled in

I set my base timing when I had my engine out this spring. I pulled the spark plugs and turned the engine until I got to the compression stroke, then stopped at TDC (stuck a pen in the spark plug plug hole). I put on an adjustable timing pointer and pointed it to 0 degrees on the harmonic balancer. I turned the engine by hand until the timing was at 10 BTDC, then dropped in the distributor and rotated it until it pointed to #1. After dropping the engine and tranny in the GT, it turned over on the first try. Good, right?

Maybe not so.

My balancer is a Pioneer 872030, the SFI race model. It has markings from 10 BTDC to 40 ATDC. I had painted it black and rubbed a white pencil over the timing marks so they show up clear. I verified timing was still set to 10 BTDC. (yes, I took the spout connector out) I know you can get pinging if the timing is too far advanced, so I decided to remove timing. I dropped the timing to about 6 BTDC, and took the car out for a spin. I expected to be down on power but the pinging should be reduced, if not gone.

To my surprise, the engine revved much easier than it had before. The pinging was there at around 2000 RPM, and the water temperature climbed to halfway within a few minutes (faster than before). Back home I went.

I then tried adjusting the timing to about 12 BTDC. The engine was a bit harder to rev up, but there was NO pinging at all! I revved it up all the way to the rev limiter several times, and no pinging. I didn't expect that. The water temperature was already at halfway from my earlier test, it was bouncing between "R" and "M".

Oh, a note for anyone that might forget this - always remember to put the spout connector BACK IN. I forgot that once, and I could hardly rev the engine. Spark advance is truly your friend.....

This morning, I advanced the timing to about 16 BTDC. I would have expected pinging to return at this point. During the drive, the car felt a little harder to rev up, but still no pinging above 3K RPMs. The temperature was reacting a bit weird as well. It didn't seem to be heating up as fast as usual, but it still got to "M". I went back home and tried out something. I sat there in park and turned on the A/C (which turns on the high speed fan). The temps creeped down to between "O" and "R", something it hadn't done before. I haven't tested enough to say for sure, but advancing the timing seems to let the engine run cooler.

My gas mileage is also really bad. I'm getting about 9-10 MPG average in city driving, a little higher on the freeway.

Any ideas? :shrug:
 
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If the dist. was 180 deg out, your car would barely run let alone accelerate. But if you wasnt to be sure you could pop off the dist. cap (with the wires and everything still connected) and pull the rotor out and install it 180 deg. around from its current position. have you checked the condition of the plugs and ignition components? Have you tried seafoam-ing the engine to remove carbon deposits? Have you checked your fuel pressure to make sure its where it should be?

I was reading thru you inital timing setting...did you verify your timing with a timing light back then? Why get an adjustable timing pointer? And also are you sure your pointer hasent shifted or otherwise lost its "adjustment". I mean I couldent even get the car to fire when my dist. was 180 deg off. I mean no sputtering, backfiring, hesitaitng...no signs of combustion at all. Just cranking and cranking and nothing. If you still have the stock pointer I would try putting that on and compare the timing you get with one vs. the other. I'd say your timing is in the ballpark of normal but something isn't quite right and I'm looking towards that adj. timing pointer.
 
if you have access to a timing light, get it and start over. pull the distributor back out, pull the #1 plug out, turn engine over by hand, listen for air, then line balancer up on 0, install distributor, crank engine then set timing. you may be a tooth or two off.

i would also try the seafoam. sounds like you may have a lot of carbon build up in the combustion chamber. i had a ping at low rpm in hot weather and tried the sea foam and it went away after that. its definatly worth a try.
 
Thanks for the replies. My spark plugs and wires are all brand new in October. No noticeable change afterwards. The idle is nice and smooth, so I'm pretty confident the coil is good.

I checked my timing after I dropped the engine back in, it was at 8 BTDC. That was closer than I thought it would be.

I swear by Seafoam, it's amazing stuff. I did run it through the engine last month, got a decent James Bond-style smokescreen. I always feel sorry for the poor sap who's behind me at that point. :p Anyone know how often one can Seafoam their engine? I don't know if there's any concern about Seafoam-ing the engine too much.

If the distributor was a tooth or two off, that would be naturally fixed by rotating the distributor. Of course, if I couldn't rotate the distributor any more I'd shift the distributor a tooth or two.

I got the adjustable timing pointer because the stock one is a "one size fits few" kinda thing. Each engine is a bit different, and 0 TDC on one engine isn't always the same on another. Besides, my adjustable pointer is a nice shiny anodized blue...how can it be wrong? :rlaugh:

Seriously now, you have a point. I checked my setting against a stock timing pointer (good thing I never bothered to throw it out), and they are different. 10 BTDC on the adjustable pointer is 6 or 4 BTDC on the stock one (hard to get my hand in there with everything in the way). I'll make sure both match, and set the timing again.
 
Yea I figured that....when you said you put a pen in there to get TDC I figured you were a few degrees off. The only way to get those adjustable ones dead nuts is if you have the head off the motor and you actually see the piston at TDC. Remember the piston moves very little over 4 deg. of crank rotation so its very easy to be off by that much. Hopefully you get the timing set right and it stops the pinging...report back and let us know. Oh and if you seafomed it last month I can't imagine it helping much now. YOu could try a colder heat range plug...but I would check your current plugs for hot spots before doing something like that.
 
You can also close the gap up on the plugs a bit. I had to do that on my car when it was bone stock. For some reason it didn't like timing at all.

BTW - 180* out = crank, crank, crank, crank, crank = BOOOOM!!! with a big blue fireball out your exhaust. Ask me how my neighbors in the townhouses were taught this lesson at 2am one morning. :D
 
Finally posting a follow-up. The adjustable timing pointer was 4 degrees off - What I thought was 10 deg BTDC was actually 6 deg BTDC. I've adjusted the pointer to match the stock pointer and reset timing to a correct 10 BTDC. I've only heard pinging once since the change, and it wasn't as bad. Instead of a bucketful of marbles, it was distinct pings. I'll probably Seafoam the engine again soon, just to make sure I didn't add a lot of carbon deposits with the bad timing.

I don't drive as much as I used to, but my gas mileage definitely seems to be much better. I'm running Premium now, but I'll try Regular again after I run through this tank and see if it pings.
 
OK, I am officially a dumb@$$....

I feel really stupid about this. :( I took the OEM harmonic balancer off the Cobra engine I'm working on (see my other thread), and just looked it over. It's all rusty of course, and it ha the same timing marks as my SFI balancer on my GT. I noticed the OEM balancer had some other markings on it; ATDC marked on the left, and BTDC on the right.

Wait, what?! :eek:

Somehow, I got the sides mixed up. I thought BTDC was on the LEFT. So I've had my timing set at 10 ATDC all this time. :mad:

I set my GT's timing to the CORRECT 10 BTDC tonight, and for some odd reason it runs a lot better. :bang: The engine revs a lot faster, and it really wants to GO! Amazing what correct timing does for an engine.

:nonono: Live and learn, I guess. I won't be making THAT mistake again.
 
Lmao, dumba*s..... lol (I did the exact same thing on my old 95) :D I swear I felt like the biggest failure ever. What makes it worse is I know about the numbers, and still over looked it for about a week, the whole time doing this :bang: :bang: :bang:



I feel really stupid about this. :( I took the OEM harmonic balancer off the Cobra engine I'm working on (see my other thread), and just looked it over. It's all rusty of course, and it ha the same timing marks as my SFI balancer on my GT. I noticed the OEM balancer had some other markings on it; ATDC marked on the left, and BTDC on the right.

Wait, what?! :eek:

Somehow, I got the sides mixed up. I thought BTDC was on the LEFT. So I've had my timing set at 10 ATDC all this time. :mad:

I set my GT's timing to the CORRECT 10 BTDC tonight, and for some odd reason it runs a lot better. :bang: The engine revs a lot faster, and it really wants to GO! Amazing what correct timing does for an engine.

:nonono: Live and learn, I guess. I won't be making THAT mistake again.