Another Timing Question

[myk]

I've got the kit, the calibration charts and stuff, but I was told that those were very generic tunes and wouldn't necessarily apply to any given car.  Testing, testing and more testing is the only way to do it, I suppose...

[grouseman]

How much timing is coming from each of initial, mechanical, and vacuum?  10 initial and 24 mechanical is ballpark, vacuum can add another 15-18. 

If you aren't getting a good steady reading on your balancer, that could be a big part of your problem.  Perhaps your balancer has spun itself out of phase? 

What are your primary jet and rod specifications, so we can figure out your jetting?  Give us either dimensions or their part numbers (it seems you're running an AFB or AVS?). 

grouseman

[RT DAVE]

I've found some other bone-headed mistakes I'm going to correct before I change any of the rods/jets/springs.  I've noticed the fuel line is not only being pinched by my drop base cleaner but it's also routed over (and touching) the valve cover.  In addition to that, I called the guy who did the work on my car and he did not adjust the air/fuel mixture.  The initial timing is set at three (3) degrees at idle.   I didn't do any of this myself, I actually paid a friend's alleged mechanic to do some work and this is the best he could do.  I'll report back for real when I know more.  Thanks to all who are posting/checking in, I appreciate all the help I've received from y'all...   

[myk]

The fuel line's travel over the valve cover shouldn't be adversely affecting the engine.  As for initial timing, I can't believe any of our engines could run 3*, heck mine's set at 19*...

[RT DAVE]

The fuel line's travel over the valve cover shouldn't be adversely affecting the engine.  As for initial timing, I can't believe any of our engines could run 3*, heck mine's set at 19*...

Unless the timing marks are wrong on my car, that's where it's at now.  Others can opine as to if it is possible to be running at 3 degrees initial timing.   Your's is at 19?  Isn't that a hella lot?  What do you idle at for it to be 19* at idle? 

[myk]

Unless the timing marks are wrong on my car, that's where it's at now.  Others can opine as to if it is possible to be running at 3 degrees initial timing.   Your's is at 19?  Isn't that a hella lot? 

I thought so too, but both Chryco and Firefighter told me a while ago that sometimes the best way to tune or time an engine is by ear and "feel."  I was told to disconnect and plug the vacuum advance, then retard or advance the timing until the engine started to pick up RPM.  Once the engine started to pick up ide, then I was supposively on the right track.  I settled on 19* initial timing and I've been satisfied with the results.  My total timing is........well, I forget, but it's like 60* at 2500 RPM or something.  My engine will run on 3* also, but not as well as it does at 19*.  Also, without leaded gas and with our engines at lower compressions, I was under the impression that 10* is usually the lowest you can go with initial timing. 
I really wish that timing thread from the old boards had made it here...

[Chryco Psycho]

if you have a total timing set at 60* & it runs well the timing marks Have to be off 

[Ghoste]

This is probably a dumb question Neil but when the timing marks are off like that, is the damper basically junk?  Do the marks continue to move once they start doing that?  Do they move very gradually over use or hop quickly all over the place?

[myk]

if you have a total timing set at 60* & it runs well the timing marks Have to be off 

Did I say 60?  I probably meant something like 38-it's been awhile since I've high-RPM timed my motor.  Where's it supposed to be at?  38, right?

[Ghoste]

Yeah, 36 or 38.  In there someplace depending on what your engine wants.

[Chryco Psycho]

generally a damper that far off is not in good condition although getting a replacement can be tough , especially if it is a cast crank /balanced damper , oftent eh cover can be off too with the timing marks not in the correct place to match the damper used , this is a big part of why I time by ear & do not use a light

[myk]

Time by ear?  I'm assuming that you merely rotate the distributor until the RPM's start to kick up to a satisfactory speed, and then lock down the distributor? 

[myk]

Yeah, 36 or 38.  In there someplace depending on what your engine wants.

Right.  Oh, but what speed are you supposed to time it at?  I've heard reports of everything from 2500 to 4000 RPM...

[Ghoste]

Ah, well that part depends on how quickly you are trying to accelerate.  For most of us on here, the 2500 figure is where you want it all in by.

[myk]

So, we want our timing in by 2500 because we want the motor to be "woken" up by at those speeds, right?  4K seemed a little late to me...

[firefighter3931]

So, we want our timing in by 2500 because we want the motor to be "woken" up by at those speeds, right?  4K seemed a little late to me...

That is correct....the faster the curve, the better (stronger) the engine will feel.


Ron

[RT DAVE]

Well, this is as far as I got before the wife complained about me stinkin up the house.  Will have to get at it again this weekend after some input.   Here's what I got so far:

First off, I'll attach a picture of the timing tab so maybe you can tell me what I'm looking at.  First off, I'm assuming the hole in the timing cover corresponds to zero.  Is that correct?   Previously, I assumed the mark that somebody put on there was zero and that's why I thought the thing was running at 3*.  My mistake.  I'm a noob.   
Anyhow, assuming that hole is zero, the thing made maximum vac of 14hg at 17 degrees.   When I went to set the idle mixture, the screws were four plus turns out from closed.  If I recall correctly, you (Ron) mentioned not to go more than 1 1/2 turns, which is what I did.   The thing made 14 hg at that amount of turns and didn't make any more beyond that.    I took a road test and brought my wrench and retarded the timing down to 10.7 and it still pings, but not as bad.   It's a dog, however.   Time to jet up or should I do a timing curve first?  How much further can I retard the timing without worrying about damaging the motor?  I want to get the vehicle to a friend's house but don't want to wreck it on the way there. Sorry about all the jibber-jabbering.   Let me know what you all think.   

[firefighter3931]

Dave, the hole in the tab corresponds to zero. The lower white line should be 10* btdc. Try mapping out the timing curve like we discussed in the pm's and see what you come up with. It could be advancing too much at higher rpms or advancing too quickly. The other issue i see is the cam. The street hemi grind is a little on the big side for a stock converter and 3.23 gearing.


Ron

[RT DAVE]

Dave, the hole in the tab corresponds to zero. The lower white line should be 10* btdc. Try mapping out the timing curve like we discussed in the pm's and see what you come up with. It could be advancing too much at higher rpms or advancing too quickly. The other issue i see is the cam. The street hemi grind is a little on the big side for a stock converter and 3.23 gearing.


Ron

Well, I only took three readings.  I think the distributor is the problem.   I set it at twelve* @850 and only took the following measurements.    25*@1500 and then 40*@2000.   Is it safe to assume this dist is advancing way too much and too soon?   I didn't take any other measurements because I thought 40* was beyond what I wanted even at 4000 much less 2000.  Let me know where to go from here.   Thanks much.   

[firefighter3931]

  I think the distributor is the problem.   I set it at twelve* @850 and only took the following measurements.    25*@1500 and then 40*@2000.   Is it safe to assume this dist is advancing way too much and too soon?   I didn't take any other measurements because I thought 40* was beyond what I wanted even at 4000 much less 2000.  Let me know where to go from here.   Thanks much.   

Bingo ! Yes the distributor has too much mechanical advance built in and the advance speed is too fast....both of which are contributing to your problems. Dave, try it one more time and keep increasing the speed until it stops advancing. I'd like to know how much mechanical advance is built into this distributor.

Is this an MP distributor ? If so, how old is it ? The New MP dist are built be Mallory and can be tuned fairly easy with their tuning kit...


And the answer to the question you're thinking of right now....Yes it can be fixed 


Ron

[RT DAVE]

  I think the distributor is the problem.   I set it at twelve* @850 and only took the following measurements.    25*@1500 and then 40*@2000.   Is it safe to assume this dist is advancing way too much and too soon?   I didn't take any other measurements because I thought 40* was beyond what I wanted even at 4000 much less 2000.  Let me know where to go from here.   Thanks much.   

Bingo ! Yes the distributor has too much mechanical advance built in and the advance speed is too fast....both of which are contributing to your problems. Dave, try it one more time and keep increasing the speed until it stops advancing. I'd like to know how much mechanical advance is built into this distributor.

Is this an MP distributor ? If so, how old is it ? The New MP dist are built be Mallory and can be tuned fairly easy with their tuning kit...


And the answer to the question you're thinking of right now....Yes it can be fixed 


Ron

I called MP and they claim the way to tell is the Mallory Unit will have an allen head screw under the rotor.  Mine doesn't, so I assume this is the MP piece.  Can you confirm from this pic?  Is this the only way to distinguish the two?  The tech said if it is an MP piece, modifying the curve would require welding & grinding, which is beyond what I have skills/tools to do.  I bought this thing four years ago. 
I'll check to see where it stops advancing, but is there a point where I should stop for safety's sake (for instance, if it goes beyond 50*)?  I would have actually gone further with it today if it weren't also for the tornadoes coming this way.  I was outside with the car because I didn't want to give my family carbon monoxide poisoning doing it in my attached garage.   
I'm considering just getting another distributor.  Would you recommend the new MP unit made by Mallory or something else?  I want to replace it with something that will be a direct replacement.   I don't want to rewire anything other than the connections at the distributor itself, if possible. I really want to get this thing on the road soon.  I haven't made any happy memories with this car since 1993 and need to make up for lost time.  My three year old daughter keeps asking for rides and wants to see a burn out.   Thanks again. 

[firefighter3931]

Dave, if you don't want to get into welding up the slots then the new MP distributor built by Mallory is your best bet. It will drop right in and plug into the existing wiring. Mallory also sells a kit to tune the mechanical advance but you probably won't need it because the "new" MP distributors are set up much better with less mechanical advance.

There's no problem checking the advance with the car in park or neutral under a "No load" condition but you wouldn't want to drive it with 50* advance.


Ron

[RT DAVE]

Dave, if you don't want to get into welding up the slots then the new MP distributor built by Mallory is your best bet. It will drop right in and plug into the existing wiring. Mallory also sells a kit to tune the mechanical advance but you probably won't need it because the "new" MP distributors are set up much better with less mechanical advance.

There's no problem checking the advance with the car in park or neutral under a "No load" condition but you wouldn't want to drive it with 50* advance.


Ron

The Mallory unit is just the normal MP piece now and not the Billet One piece dist, correct? 

[firefighter3931]

Dave, if you don't want to get into welding up the slots then the new MP distributor built by Mallory is your best bet. It will drop right in and plug into the existing wiring. Mallory also sells a kit to tune the mechanical advance but you probably won't need it because the "new" MP distributors are set up much better with less mechanical advance.

There's no problem checking the advance with the car in park or neutral under a "No load" condition but you wouldn't want to drive it with 50* advance.


Ron

The Mallory unit is just the normal MP piece now and not the Billet One piece dist, correct? 

Yes, that is my understanding. Maybe a call to MP to confirm is in order. 


Ron

[RT DAVE]

Dave, if you don't want to get into welding up the slots then the new MP distributor built by Mallory is your best bet. It will drop right in and plug into the existing wiring. Mallory also sells a kit to tune the mechanical advance but you probably won't need it because the "new" MP distributors are set up much better with less mechanical advance.

There's no problem checking the advance with the car in park or neutral under a "No load" condition but you wouldn't want to drive it with 50* advance.


Ron

The Mallory unit is just the normal MP piece now and not the Billet One piece dist, correct? 

Yes, that is my understanding. Maybe a call to MP to confirm is in order. 


Ron

I actually called them yesterday and the guy I talked to didn't know.