Ignition: r2 timing problem

[59r2]

My problem is timing on my r2 with the mopar conversion in a prestolite dis.I tried to search but can't find this problem. I set the timing with the vacum adv. disconnected to 24 degrees @ 1600 rpm tighten the dis and let it idle it reads about 4 degree atdc .hessiates hicups and is slow to rev.If I bring it up to 2200 the timing mark is almost out of sight on top I and guessing at about 32 degrees bftdc. Called dave t-bo ,It's one of his dis ,he tells me to set it @8 degrees at 650rpm ,but when I bring it up to 2200rpm the mark goes out of sight over the top the vib damper, And I still have hesitation from idle to rev. So I advance it to 14 degrees btdc at 650 lockit down ,rev to 2200rpm the mark goes out of sight but no heitation and runs like a raped ape,but I am afraid to leave it there (at this setting there is no ping or detination that I can feel or hear). Also after setting the dis I connect the vacum line and there isn't anychange in the mark at idle at any of the settings.I checked vacum bleed down on the vacum advance and the points plate moves and the diafram holds vacum.At this setting of 14 degrees is what the car turn a 15.2 at the drags, my concern is I have to drive 400 miles to be in a wedding next week,and am trying to find out if I can drive a distance @2500 rpm and not hurt anything.
Thanks
JOE

1959 HARDTOP R2 clone
1960 conv
SDC member since 1972

[PackardV8]

quote:14 degrees atdc at 650

??? Too many numbers in the post which don't compute. Usually Dave's distributors are right on, but verify it. If he sent you something off, he'll make it good. You can chase the problem around on the engine, but seems you've lost the rabbit. Why not start with known points?

1. Verify the TDC mark you are using is really Top Dead Center of #1 cylinder.
2. Take your distributor to someone with the good old-fashioned Sun machine and have him show you the centrifugal and vacuum advances are what they are supposed to be.
3. Try another known-good timing light. The dial-back lights are especially prone to weirdness.

Get those three right and it will drop in and run as it is supposed to.

thnx, jack vines

PackardV8

[bige]

The problem is the centrifugal advance. I bought a Mallory unit from Dave and he confirmed that the Centrifugal was the standard Chevy Setting that came with the Mallory unit from the factory. That unit is a lot easier to adjust than the Chrysler so my guess is that factory MOPAR settings are in place not Stude R2 settings.

A HP BB Chrysler would typically set to work with 10-12 static advance and another 24-26 centrifugal. And that may not all come in until 3500 RPM. So if you haven't reworked the weights and springs in the distributor when you set timing at 24 @ 1600 you are not maxed in centrifugal timing the way a stock R2 distributor would be. You are only at the beginning of the curve.

You need to run weak springs but limit the movement of the shaft that way the centrifugal comes in quickly but doesn't continue to advance. As a point of reference. With the Mallory unit I run around 12 degrees static and have it set to add a total of 14-16 degrees of advance.

If Dave uses a Mopar HP distributor it should have an adjustable vacuum advance can. Not as big an issue as the centrifugal but you could run into a detonation issue if it's pulling another 20 degrees or so on top of total mechanical advance.

To recurve your distributor you would need to remove the breaker plate to get to the weights and springs. You will be able to see how the system works. I have used a plastic protractor to mark degrees on the dist body to see how far the rotor shaft moves, in degrees, and then did my thing to limit its movement. At the distributor the degrees are halved so if you want a total of 14 at the crank you need to adjust for 7 total at the distributor. Using springs to limit the movement won't work because it will affect how quickly you get your advance. A heavy spring may work to limit the shaft movement it will slow your curve down or eliminate it entirely. On the R2 you want it to come in full at 1600 so the springs need to be light but also make sure you get complete return. Otherwise your timing will be erratic at idle.

I think you are right to be concerned about leaving it that way. Without going into a very long story I've had my timing set ALL OVER THE PLACE and never heard a ping. The only hint I would get that it was too far advanced was a labored crank. You may be doing damage with no audible warning.

BTW, You won't get a vacuum signal at idle because you are taking vacuum off a timed port. It will only get a signal if the throttle is opened far enough to expose it to the air stream. That's the way it should be set up so don't change anything.

ErnieR

[Mike Van Veghten]

See what timing lights can do.........muddy up the waters thoughtly.

Try this...
Loosen the distr. clamp slightly, warm up the engine, with the engine running, advance the distributor timing until you get the highest idle speed, then retard it..just a "little" bit, shut it off, tighten the clamp.

Now go for a drive...how does the car feel?
Does it ping under a load?
Is it peppy?
Stop where safe and give the distr. a "little" more advance, tighten the clamp...how does it feel now? Do this a coupla times to find the "happy spot".

GIVE THE ENGINE WHAT "IT" WANTS....NOT what you "think" it should have...!

Now...hook up your light...see what timing values you actually have...write it down for history and for later possible further experimentation.

Recheck your idle speed as required, readjust your carburetor as required.

Mike

[bige]

I agree with Mike on not staying too focused on the numbers themselves. But I can say that while my car felt great low and midrange with lots of advance it lost some power at the top of the RPM range. I found giving up a little of the low end snap you get with lots of initial advance that the overall pull throughout the RPM range was better when I retarded it back a few degrees. And because I've never been able to discern an audible knock I have been conservative with the overall timing trying to keep it close to factory specs.

ErnieR

[studelover]

We were working on this very thing today 61 hawk 289, after we adjusted the valves and changed a couple of rocker arms( the screw threads were shot in three) we had the motor running great, almost no valve noise. Then it was time to check the timing. At first we kept trying to time it according to the book then broke out the vac. gauge. We decided to adjust it to where it ran at it's optumun. The hole shot is sweet and it starts very quick. We have no ping. We are running high test gas[]The exhuast sounds healthy and almost as strong as a small block chevy. All the modifications paid off as the car really performs very well.We are very pleased with the parts and services we used and this cam has a lope to die for

Studebakers forever!

[N8N]

Ernie, sounds like you need *less* centrifugal advance and more static... have you tried limiting the centrifugal and bumping up the static a little?

nate

--
55 Commander Starlight

http://members.cox.net/njnagel

[bige]

That is what I was saying...Mopar distributor has too much centrifugal. Limit centrifugal bring up the static did I mis-type?[?]

ErnieR

quote:Originally posted by N8N

Ernie, sounds like you need *less* centrifugal advance and more static... have you tried limiting the centrifugal and bumping up the static a little?

nate

--
55 Commander Starlight

http://members.cox.net/njnagel

[bige]

If you were referring to the post about my car...that is how I have it set up. The fact that I have driven it with way too much advance at times and never noticed a ping or a knock initially lead me to believe that my seat of the pants settings were good.

Some real testing at the dragstrip revealed that performance was better with a little less initial to come up with a happy total around 28. Every car is different and the Avanti is the only car I've ever had in which I could not detect an audible knock. I know that doesn't mean it's not happening just that I can't hear it. Hence my caution about seat of the pants tuning with too much initial on an R2.

When I backed the initial down a little and stretched the centrifugal, idle quality improved and the general feel of the car was better, smoother is the best way to describe it.

At the time I was playing at the dragstrip I was running a self curved Delco Window with a Pertronix, this was a Stude distributor to begin with but not set up for an R2 and it had too much centrifugal and not a quick enough curve ( I have a Sun Machine ). Changing weights, springs and some other tweaks gave me a curve that would allow more initial without the overall going above 30 total. Basically 15 degrees centrifugal at the crank. And like Joe's car it likes 12-14 degrees static.

Peter Sant and I had discussions about timing (before he became famous) and he ultimately ran best with 28 total also.

But I've actually driven it with 18-20 ( where the vacuum gage says I should keep it ) experimenting with total advance like the Brand X's use-34-36 total. No Ping!! Hard start when hot, engine had lots of low end but felt tight and strained throughout the rpm range. Stretching the curve to give me the same total at lower static didn't improve the overall performance. It just runs best close to factory specs, speaking strictly for my car.

BTW, I only switched to the Mallory because it's easier to tune and I seemed to be getting spark scatter with the Delco. Turned out the gear on the Delco was not being held snug by the roll pin. I never put it back in after I repaired it so I don't know for sure if that was the reason.

quote:Originally posted by N8N

Ernie, sounds like you need *less* centrifugal advance and more static... have you tried limiting the centrifugal and bumping up the static a little?

nate

--
55 Commander Starlight

http://members.cox.net/njnagel

[Kenmike2]

Haven't used a timing light in years and have set timing hundreds of times on many different cars even non Studebakers.
Let's look at some basics: The gasoline engine is merely a sophisticated "air pump". When it's pumping air at it's peak ability it's also at it's most efficient operating point. You can know when it's at it peak by when it's producing the max amount of vacum that it is capable of. This will even give you the optimal setting if you have a small vacum leak at the carb or the intake manifold.

So, here's how I set the timing on any engine: Verify the dwell is correct. Disconnect the vacum advance. Hook up your vacum gauge to the real constant vacum souce, the intake manifold. Direct, do not go thru the carburetor base. Start the engine. Advance the timing until the engine begins to "roughen up" Back up 1/2 half inch of vacum and lock it down. Road test, start test, etc. and everything should be perfect.
Technical logic: When the engine is at its "sweet spot" it will, by definition be at it's optimal. Doesn't matter what the timing light says. I have seen Studebaker engines where the timing mark was "off" by as much as ten degrees in either/both direction Plus or Minus. With timing set this way you don't care where the timing marks may be.

[WCP]

In setting up a "Stude" window Delco for the R2, you definitely need to add the centrifugal advance limiter bushing that GM used. As well, a Crane adjustable vacuum advance with an advance limiter, will allow you to replicate the factory R2 curve very closely. Good performance with a Pertonix!