Advancing my base timing

[Skandocious]

The problem with advancing the base timing on an application like this is that you are also advancing the entire timing table. The only way that I know of to get around that is to use a tuner. So, is 14* base timing in and of itself a problem? As long as you can start the motor...then no. But is there any other spot in the timing table that got advanced far enough to possibly damage the motor? I have no idea. Thats the chance you are taking. All it would take is enough heat in a cylinder (ie. from a load) and enough timing advance in that cylinder to ignite the air and fuel too soon. Then what you have is combustion taking place early enough in the compression stroke to where the power generated by the combustion is actually trying to push the piston back down. Thats bad...

Good point. So how much is too much on a stock 351W? Anyone know? I've seen plenty of guys over on the other site running at 14*, that's why I assume it's safe...

 

[eco]

Good point. So how much is too much on a stock 351W? Anyone know? I've seen plenty of guys over on the other site running at 14*, that's why I assume it's safe...

Can't say for sure, but it is *probably* not a problem.

Is that your truck on the far right of the top of the page?

 

[Skandocious]

No that's Ryan's truck, one of the admins.

Left in bobf100's, center is Blue Goose's (admin), right is O'Rattlecan's (admin).

 

[eco]

Good post, ECO. But one thing I have seen, Scandocious is very well educated and aware of how his truck works. We dont need any sparks here.

The question about which cable he clamped was a bit of a joke, just like I assume your "did you put the spout back in?" question was.

I have read enough of skan's posts (here and elsewhere) to have a *fairly* good idea of how advanced his mechanical abilities are and how extensive his knowledge is, and he is still a bit of an amateur (not that there is anything wrong with that) in the big picture, and frankly, so am I in many ways.

As far as not needing any sparks, as long as they are properly timed the sparks are OK....thats what this thread is about, right?

 

[Skandocious]

As far as not needing any sparks, as long as they are properly timed the sparks are OK....thats what this thread is about, right?

All in good fun.

Truck seemed like it got a little better gas mileage on the way home tonight... Ehhh, wth? Am I imagining things or could I have gained performance AND improved my mileage by altering my timing?

EDIT: Damnit I passed up my 2000th post without even noticing!!! Lame.

 

[eco]

Makes sense to me...

More power per power stroke without changing the way the motor breaths would mean that the throttle would need to open slightly less to achieve the same amount of power at the wheels. Less throttle = less fuel.

 

[Skandocious]

Makes sense to me...

More power per power stroke without changing the way the motor breaths would mean that the throttle would need to open slightly less to achieve the same amount of power at the wheels. Less throttle = less fuel.

Yes I suppose that makes sense. Win/win

Eco tell me your real name, I'm dying to know. If you're uncomfortable then just say so, if not, LETS HAVE IT!

 

[Fellro]

It is entirely likely to have gained by bumping up a bit. Between timing chain stretch like mentioned earlier, balancer ring walk, distributor wear and all that, it can get retarded. If retarded then the spark misses the optimum time to fire and push the piston back down. It either will chase the piston down if retarded, hit at just the right time, and produce good power and efficiency, or be too advanced, and push against the piston as it still travels upward. The best time to fire is right as the crank passes TDC.For emissions reasons, the factory tunes just a little retarded, which doesn't produce the best power or efficiency. Add that to normal wear, and you lose power and efficiency. Which reminds me that it should be added to my to-do list on the 88 I am driving right now...

 

[Skandocious]

K digging up an old thread...

Andy is scaring me now, telling me that even though I can't HEAR the pinging it could still be happening and damaging my engine. All you gurus out there, is 14* BTDC going to cause harm to my engine or is that a small enough advance that I'm not hurting anything....?

EDIT: Just remembered I've got a Motorcraft harmonic balancer coming in the mail, so I'm going wait to worry. My balancer ring could have walked a bit (the rubber is deteriorating) so we'll see what my timing ACTUALLY is once I get the new balancer on this weekend.

 

[andym]

The answer is that every engine, even though they roll off the same assembly line, is made of thousands of different parts. They are all within tolerance, but with the vast array of electronics and mechanicals on your engine, there are literally thousands of variables that will determine your optimum timing setting.

In short, no one knows. Setting the timing is a not an exact science, and Ford picked 10 BTDC as a compromise of longevity, power, and emissions. How far you can stray from it without causing damage in the long term is anyone's guess.

 

[eco]

You could always run premium fuel. If running a higher grade fuel makes a difference for the better (with the 14* timing) in how the motor runs/feels, then odds are that the premium fuel is not preigniting where as the regular fuel was and that acounts for the difference. If there is no performance difference between the two fuel types, then there was probably no preignition in the first place. Since the preignition is pushing the piston down when it is still on it's way up, it is counterproductive by nature and damaging to the motor. If that counterproductive preignition that you can't hear goes away due to the fuel (which is should), a perfomance gain should be noticed as long as nothing else is changed. So, leave the timing where it is and try a tank of 92 octane fuel. Nothing to lose and everything to gain so it's worth a try.

Just an idea...

 

[Skandocious]

You could always run premium fuel. If running a higher grade fuel makes a difference for the better (with the 14* timing) in how the motor runs/feels, then odds are that the premium fuel is not preigniting where as the regular fuel was and that acounts for the difference. If there is no performance difference between the two fuel types, then there was probably no preignition in the first place. Since the preignition is pushing the piston down when it is still on it's way up, it is counterproductive by nature and damaging to the motor. If that counterproductive preignition that you can't hear goes away due to the fuel (which is should), a perfomance gain should be noticed as long as nothing else is changed. So, leave the timing where it is and try a tank of 92 octane fuel. Nothing to lose and everything to gain so it's worth a try.

Just an idea...

Suppose I could get it a try... With my tiny gas tank I'd really only end up paying a couple dollars more... I'll probably give that a go after I get the new balancer on.

 

[Old_Paint]

You get the new HB installed yet? I've seen/heard of some running as high as 18* BTDC base, and getting away with it, but it DID require running premium (92 Octane) fuel. I read a good thread somewhere about checking slack in the chain, with non-invasive technique. Essentially, take the dizzy cap off, and rotate the crank forward, then start slowly turning it backward and see if there is a pause in rotation of the rotor. Normally, what a slack chain will cause, though, is a loping idle, and probably some surge as the IAC tries to compensate for the speed changes. I speak from experience on a tired 3.8 V6 that has been replaced by a long block in my T-Bird.

 

[Skandocious]

Nope, haven't replaced the HB yet cuz I haven't been home (it shipped to my mom's house). I'm going home tomorrow after my final (spring break WOOO) so I plan on knocking out that job first thing, then I've got a few others I wanna take care over the course of the week.

And I think I'll try that method for checking chain slack, thanks Tim!

 

[eco]

Nope, haven't replaced the HB yet cuz I haven't been home (it shipped to my mom's house). I'm going home tomorrow after my final (spring break WOOO) so I plan on knocking out that job first thing, then I've got a few others I wanna take care over the course of the week.

Did you install the HB yet?

 

[Skandocious]

Hmm, I could swear there was another thread about that harmonic balancer... Yeah I got it installed a long while ago. Lemme see if I can dig up that other thread.

EDIT: Knew it. Here's the thread:

http://www.fordtruckfanatics.com/forum/showthread.php?t=3891

 

[Mr. Stroker]

Where is the spout connecter? Anyone got a pic? And skan what do you have your timing at right now.??

 

[Skandocious]

My timing is currently at 14* but I'm gonna bump it back to 12 or 13* as soon as I get my hands on a timing light. The spout connector is a little gray plastic cube-like thing near the driverside fender well. It looks like the gray thing in the picture below, though the black harness that it plugs into looks different on my truck:

 

[Mr. Stroker]

Ok thanks alot man. Il probably attempt to free up my distributer and bump it up to 12..