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View Full Version : Timing experts, please check my work



MagikDraggin
04-21-2007, 10:23 PM
Was 80 today and had the Hawk out for a nice "spin" in the country. Ever since having purchased this ride, I have noticed what I thought was a sluggish take off and not too impressive throttle response. But I figured it was an old car and I shouldn't be expecting too much from it.

So, I broke out the old induction timing light I had left over from my Mopar days and checked the timing. I set the idle at 600 rpm, flipped on the timing light, goosed the throttle a little bit just to see if the vacuum advance was working and it was.....so I disconnected and plugged the vacuum line and checked the actual timing.

If I understand the (clear as mud) repair manual, I presume the pointer should be lined up with the "I" in the letters in "IGN" that's on the vibration dampner. Unfortunately, it was about 2" away from it on the "retard" side of the mark.

So, I loosened the distributor clamp and rotated the distributor until the pointer was dead on the letter "I". And in doing so, the idle raised up to nearly 1000 rpm.

I reset the idle back to 600 rpm and readjusted the idle mixture screws and now the Hawk literally PURRS when it idles. The big surprise was when I took it out for a followup test drive. It's like a brand new car now. Takes off like a scalded rabbit, excellent throttle response, no lagging when I give it the gas, unbelievable difference.

Sorry for being so long-winded here......now my question: Did I do this correctly? That is, since there are no "degreeing marks" on the dampner (who's brilliant idea of genius was that, anyway?), is it set properly when the pointer is at the "I" of the letters "IGN"?

If so, just how "forgiving" are these Stude motors if the timing is set a couple degrees further advanced than what the manual calls for?

Karl

http://img.photobucket.com/albums/v147/MagikDraggin/Other%20Stuff/IM000986-reduced.jpg?
1962 GT Hawk 4sp

Tom B
04-21-2007, 11:04 PM
To the best of my knowledge 4 to 6 deg advanced are a good thing, but without degree marks, it's a crap shoot. Keep advancing it till it pings, then back off a bit.

[img=left]http://www.alink.com/personal/tbredehoft/Bothcars.jpg[/img=left]
Tom Bredehoft
'53 Commander Coupe
'60 Lark VI
'05 Legacy Ltd Wagon
All three Indiana built OD cars

MagikDraggin
04-21-2007, 11:12 PM
quote:Originally posted by hotwheels63r2

IGN would be zero, so by setting it a little bit past that, you are running slightly advanced. I think the book would call for 4 degrees.

I'd leave it about there, unless she pings. An adjustable timing light is the correct way to do this.

Anyone know how far you can go with a good running engine? (lets say in 16ths of an inch)

I'm running 8 degrees advanced on an adjustable timing light.....


Hmmn, you'll have to excuse me here, but just what is an "adjustable" timing light? What does it actually "adjust"?

The one I have is what is called an "induction" timing light circa 1975, and is actually a "professional" unit which has a pick-up that clamps onto the number 1 plug wire, reading the pulses by way of, well, by way of "induction".

It does a good job of providing a nice bright and accurate pulse. The problem (and I hope I don't offend any serious afficionados here with my remark) is the Mickey Mouse way of actually setting the timing without benefit of some sort of logical timing scale (as is found on the Supercharged motors, for example).

Anyway, it runs good and hard now and does not "ping", so I guess all is well. It just would be nice to actually KNOW where the timing is when I advance it beyond that Letter "I".

Karl

http://img.photobucket.com/albums/v147/MagikDraggin/Other%20Stuff/IM000986-reduced.jpg?
1962 GT Hawk 4sp

GTtim
04-21-2007, 11:20 PM
Karl, you done good! One of the most rewarding things about tinkering with these old cars is realizing that you can make them 'purr' and 'sing'. By careful listening and experience, you too can have a car that runs great, starts dependably and gets decent gas mileage. I had done a little car tinkering in my teens and on and off through the years but only since getting the Hawk have I spent a lot time trying to figure out the intricacies of a well tuned engine. Others here know a lot more than I do and some do this stuff for a living, but I'll give you a solid thumbs up for the effort you are putting into making your Hawk a good running car and understanding just what goes into making that happen.
One more way, besides listening for pinging on hard acceleration, is to listen to how the car starts. If the starter turns the engine over smoothly, that's good. If the timing is too far advanced the engine will 'fight' being turned by the starter. You can keep advancing the timing until this happens as way of actually hearing what I'm talking about, no harm will be done.
In general the Stude engines are pretty forgiving and can stand quite a bit more advance than the book calls for. Remember the book is written so the cars can be set to those specifications and work reliably given a wide assortment of driving variables and gasoline qualities and not be brought back to dealer because of problems.

Tim K.
'64 R2 GT Hawk

gordr
04-22-2007, 12:36 AM
An adjustable timing light, also called an "advance timing light" has a knob on it calibrated in degrees. This knob controls the time delay of the flash event from the trigger event. If you set it to 6 degrees, the ZERO mark (UDC on a Stude V8) will show up next to the pointer if the distributor initial advance is set to 6. If full mechanical advance is supposed to be 24, then with 6 initial advance, you should be able to dial the advance timing light to 30 and see the UDC mark by the pointer when revved up to about 2400 RPM. Note: if you are using the advance feature on the timing light, ALWAYS read the timing at the UDC mark, not at the IGN mark. The IGN mark is used only if you have an old-fashioned timing light without the adjustable feature, or if you set the advance knob to zero.

Incidentally, there should be a scribed line next to the IGN mark; you aren't supposed to time to the actual letter "I". (but you won't be much more than 1 degree out by so doing) The scribed line is shallow, and goes the full width of the damper disc edge. I like to clean the entire area well, and mark the lines and letters with a white or yellow paint stick. Sounds like you have an inductive pickup timing light without the advance feature. Perfectly OK for checking initial advance; but the adjustable ones are nice for checking the total advance in the distributor. You could also measure out along the perimeter of the balancer disc, and make a mark at the point where total advance at 2400 RPM should be. My shop manual says 24 mechanical advance at 2400 RPM, and 16 vacuum advance at 12" vacuum. I'd suggest you mark the harmonic balancer at the 16 and 24 degree points, then temporarily set the initial advance to zero, and measure the mechanical and vacuum advance separately. If they are both within spec, then reset the initial advance to 6 degrees, and you should be good to go.

If your car has a prestolite distributor, be advised they are notorious for over-advancing due to wear in the centrifugal adavnce mechanism. If you find this problem, get it fixed, and your hawk will be much happier.

Gord Richmond, within Weasel range of the Alberta Badlands

MagikDraggin
04-22-2007, 01:16 AM
To both GORDR and HOTWHEELS63R2......Amazing what a person can learn from this forum. In regards to adjustable timing lights....I had no idea. Is this something relatively new, or simply old technology that I somehow never was exposed to over the years?

On the old '64 Fury I had, I ran it without any vacuum advance, only mechanical advance and set it all with the Induction light I have. On this Hawk I now have, I do recall seeing some sort of illegible lettering or markings that the pointer was set on which was a considerable distance from the "IGN" letters, before I moved it up (advanced it) to the "IGN" line.

And yes, you are so right GORDR, there is a "line" directly in front of the "IGN" letters. I marked it with white paint for future reference. I hadn't really noticed that before you mentioned it....but the manual does make it a point of mentioning lining up the pointer with the "IGN" letters.

I honestly don't have the foggiest idea what it is presently timed at, but I am satisfied with how it runs now and there is no pinging, and it starts up fine with no pain or strain.

Now all I have to do is locate a rebuilt WCFB carburetor to cure the excessive sooting from there being too much fuel being dumped into the intake plenum, (I don't work on those kind of carburetors) and this Hawk will be ready to "fly".

I just might make it to South Bend yet. :D

Karl

http://img.photobucket.com/albums/v147/MagikDraggin/Other%20Stuff/IM000986-reduced.jpg?
1962 GT Hawk 4sp