[Kelly_H]

I'm confused here because I have seen a lot of conflicting information and I think I'm not reading the manual quite right. Here's the deal:

I have a 289 HiPo distributor on my car. I'm not sure if it's advancing as much as it should be so I need to know how much it should be advancing, total. Currently it is only advancing 12 degrees from idle to 3000 rpm.

The shop manual says that the "maximum advance limit" is 14*, which seems to imply to me that it should be advancing a total of 14* between idle and 3000 rpm. But then I have read a bunch of posts where people are starting with 12* initial timing and ending at 36-40* final total advance, which is obviously not a 14* difference! So could someone please educate me on what the difference here is and what I should be shooting for?

Thanks in advance for the help - I have read up on the threads but something just isn't clicking between the table in the manual and what people have been saying.

 

[GT289]

Distributor degrees is always X2.
And then add in the initial timing.

So lets say you've got 13 degrees mechanical- that's 26 degrees in reality.
And you're set at 10 degrees on the harmonic dampner..... that's 36 total degrees of advance MAX.

You can check where you really are with an advance timing light. That's the only way to truly know.
(outside of a distributor testing machine) You can plot the curve and see the changes you made
without needing access to the machine itself.

 

[Kelly_H]

So total advance should be 28* if the "maximum advance limit" is 14*?

If so... I guess that means there's something up with the distributor since my dial-back timing light is telling me it's only advancing 12* from initial to all in.

Edit - saw that you edited your post after I had replied. So there is definitely something wrong with my distributor. Currently it is set at 20* initial and it ends up at 32* at 3000rpm. I am well aware that the 20* is not anywhere close to right with the motor, but I had to put it where it was "happiest" for my recent trip.

I'm going to take apart some of the distributor and see what I can see. I'll take pictures in case anyone sees anything glaringly wrong that I don't know to look for. Otherwise it may be rebuild time! Bummer.

 

[zray]

I'm confused here because I have seen a lot of conflicting information and I think I'm not reading the manual quite right. Here's the deal:

I have a 289 HiPo distributor on my car. I'm not sure if it's advancing as much as it should be so I need to know how much it should be advancing, total. Currently it is only advancing 12 degrees from idle to 3000 rpm.

The shop manual says that the "maximum advance limit" is 14*, which seems to imply to me that it should be advancing a total of 14* between idle and 3000 rpm..

Are you using the Ford shop manual. If so you will see that the HiPo dist. is not finished advancing at 3,000, (with the stock springs).

You have to really goose the throttle to get the full 28 degrees of mechanical advance. There are two slots on the distributor advance mechanism. 10L & 15L. The advance will be double those numbers less two degrees*. So the correct slot should be the 15L. ( 12 degrees initial plus 28 degrees mechanical = the factory recommended timing for a HiPo engine. Check to see you are in that slot.

*. Less two degrees because there is a sleeve around the post which keeps the advance weight from going all the way.

Remember, you don't have a HiPo engine, right? So you might want to set your timing for the engine you have installed. Might be prudent to sell the HiPo distributor and get the correct dist. For your car, just sayin'.



Z

 

[GT289]

So total advance should be 28* if the "maximum advance limit" is 14*?

If so... I guess that means there's something up with the distributor since my dial-back timing light is telling me it's only advancing 12* from initial to all in.

Edit - saw that you edited your post after I had replied. So there is definitely something wrong with my distributor. Currently it is set at 20* initial and it ends up at 32* at 3000rpm. I am well aware that the 20* is not anywhere close to right with the motor, but I had to put it where it was "happiest" for my recent trip.

I'm going to take apart some of the distributor and see what I can see. I'll take pictures in case anyone sees anything glaringly wrong that I don't know to look for. Otherwise it may be rebuild time! Bummer.

Too much initial in my opinion. I run my 289 4bbl at 13 degrees initial and get the
rest from the distributor itself. It's curved like the hipo distributor. I think mine is
set for 25/26 in the distributor.

I'm surprised you can start your engine with 20 degrees initial timing.

 

[Kelly_H]

Ok, well here's the first dumb question: is the rotor "locked down" on the distributor at all points other than when it's pointed to cylinder #1? Because I don't remember it being that way... and if it isn't, then my rotor is somehow stuck on there. Tips on getting it off?

The only table I have found in the Ford shop manual is the one for C5OF-12127-E (which is the distributor I have). It lists:
Distribtor (rpm) | Advance (degrees | Vacuum (irrelevant as there is none)
650 | 2.25-3.75
750 | 4-5.5
1000 | 6.5-7.5
1600 | 7.5-8.75
2000 | 8.25 - 9.75
Maximum advance limit.................... 14*

So while I knew that it continues advancing past 2000 rpms, I didn't really have any way to know what I should be getting at what rpm. So I just held down the throttle until the white mark on the balancer quit advancing. I revved the car to probably around 4000 rpms - maybe higher, hard to say because I can't rev it and look at the tach and the timing light all at the same time. Nobody to sit in the driver's seat and hit the gas for me so I had to kind of go by ear. If it advances further than what I found, then there is a major "flat spot" where it doesn't advance at all that fooled me into thinking it was all in.

There shouldn't be anything stopping me from running the HiPo distributor as far as I can tell, assuming that it is properly working. It has worked fine in the past - I remember timing it way back when a few years ago and it was happy at 12*BTDC initial (and I have the mark on the balancer to corroborate that). It's just that now it doesn't like 12*BTDC because that puts it (as far as I can tell) all in at 24* total advance which is horrible!

 

[Kelly_H]

Too much initial in my opinion. I run my 289 4bbl at 13 degrees initial and get the
rest from the distributor itself. It's curved like the hipo distributor. I think mine is
set for 25/26 in the distributor.

I'm surprised you can start your engine with 20 degrees initial timing.

Yeah, I know 20* is too much initial. But I had to put it where it would run and be happy (or as happy as it was going to get). If it's only advancing 12 degrees and I put it at 12* initial that would put my end timing at 24 degrees. To verify I just checked that with my timing light. So I guess 20 degrees is the kind of mid-point that lets it run okay at higher rpms and still start okay.

I'm surprised this engine runs at all most of the time, to be honest! I am not kind to it though not for lack of trying. Just learning, that's all. I imagine that maybe the EFI helps it start more easily.

 

[zray]

Are you using the Ford shop manual. If so you will see that the HiPo dist. is not finished advancing at 3,000, (with the stock springs).
Z

Got out the shop manual to see the published specification :

At distributor rpm of 2,000 the advance should be 8.25 to 9.75 degrees. You need to double those numbers to get crankshaft rpm and crankshaft degrees.

So that would be at 4,000 engine rpm the distributor should be advanced by 16.5 to 19.5 degrees. Far short of the 28 degrees of mechanical advance that the distributor has AT FULL ADVANCE. So after 4,000 rpm and sometime before the redline of 6,000 rpm, the engine advances another 8.5 to 11.5 degrees to get to the full 28 degrees of mechanical advance.

Now, Kelly, with the driving you do, it's not likely that you are getting enough advance at cruising rpm . If you keep the HiPo distributor I recomment getting a set of the Mr. Gasket 925D advance springs, summit has them. Just install one of them , and keep one of the stock springs. That will give you full advance at about 4.000 +/- rpm; better torque at the rpm range where you are driving most of the time , and your gas milage should improve.


Z

 

[Kelly_H]

Nevermind on the rotor thing - it was just playing hard to get

Here are pictures of the inside of the dizzy. One plate is labeled 13L and the other one is labeled 18L. Nothing appears to be broken - to my eye, at least.

Either of you guys see anything interesting?

I can close it back up real quick and re-check how much timing I'm getting but I am fairly sure that I maxed out however much it was intending to advance.

Steps to proceed from here?

 

[Kelly_H]

Got out the shop manual to see the published specification :

At distributor rpm of 2,000 the advance should be 8.25 to 9.75 degrees. You need to double those numbers to get crankshaft rpm and crankshaft degrees.

So that would be at 4,000 engine rpm the distributor should be advanced by 16.5 to 19.5 degrees. Far short of the 28 degrees of mechanical advance that the distributor has AT FULL ADVANCE. So after 4,000 rpm and sometime before the redline of 6,000 rpm, the engine advances another 8.5 to 11.5 degrees to get to the full 28 degrees of mechanical advance.

Now, Kelly, with the driving you do, it's not likely that you are getting enough advance at cruising rpm . If you keep the HiPo distributor I recomment getting a set of the Mr. Gasket 925D advance springs, summit has them. Just install one of them , and keep one of the stock springs. That will give you full advance at about 4.000 +/- rpm; better torque at the rpm range where you are driving most of the time , and your gas milage should improve.


Z

Ok, so I still have a problem then if I am seeing only 12* of advance at 4000 rpm. That's 6* on the distributor at 2000 rpm, which is only 2/3rds of what it should be giving me, correct? Given that I have just discovered that there's a 13L (whatever it is) in there instead of a 15L, how does this affect those numbers?

I'll put it all back together and fish a cable through for my laptop so I can hook it up to the EFI and see it from my engine bay. Then I will be able to figure out exactly how much advance I'm getting at what rpm.

Still don't understand why it wants to be at 20*BTDC though...

 

[zray]

The 13L slot should give you about 26 degrees of mechanical advance, which is fine.

But you are only getting 12 degrees at 4,000 instead of about 19 or 20. You need to take off the advance unit, clean it , and put in a weaker spring on one side, and you should be back in business.

(..... I'm still of the opinion that you would be happier with the vacuum advance distributor that is corrct for your engine....)

Z

 

[Kelly_H]

Which side should the weaker spring go on? One spring is really heavy looking and the other looks really light.

When I reinstall the advance unit, should I be greasing it with anything? If so, what and where?

I don't think I understand how the advance unit can be causing it to stop advancing at a certain point - that seems like a spring problem? If so, why would I have it now and not two years ago when I've never touched the thing?

I had a different distributor, once. It lasted for three weeks before my car destroyed the entire thing (somehow). I now prefer to keep what is known to work. I don't have the funds currently to buy anything new at any rate so it is a moot point.

 

[zray]

It could be sticking due to grease or rust build up.. I dont know if your springs are stock. The HiPo distributors I've seen have both springs the same. But I haven't seen ALL of them ! Don't worry about having a 13L slot vs. my 10L & 15L Ford sent out different advance mechanisms depending on the year and whether it was going one manual or automatic. ('66'only)

Z

 

[GT289]

18/13 is supposedly a valid hipo distributor cam. It definitely is
correct for 289 2 & 4bbl.

I second the take it apart and clean it. I guarantee that there's
a ton of crud on the upper shaft where the cam is supposed to
rotate back and forth freely. (well, freely against spring tension)

I "think" the hipo Autolite distributors may have had the same
tension in both springs. I once owned a Motorcraft hipo unit
that I bought over the Ford counter and one spring was lighter
than the other. If Kelly's is marked Motorcraft, that may explain
that circumstance.

Mechanical advance is controlled by which "window" you're
using. (By your photo, yours was in the 16 degree window)
You could rotate it and run it in the 18 degree window and
back down the initial timing to 6 or so.....

Kelly- you should have mentioned your distributor deal at
Knottsberry. We could have talked about it in person.

 

[GT289]

Mechanically, if you were modding pieces, here's how it works out......

To figure approximate slot width for a given advance figure,
multiply the number of desired centrifugal degrees by .013"
then add .150" to account for the width of the stop pin.
8L slot = 16 degrees centrifugal advance = .358"
9L slot = 18 degrees centrifugal advance = .384"
10L slot = 20 degrees centrifugal advance = .410" Total slot width
11L slot = 22 degrees centrifugal advance = .436"
12L slot = 24 degrees centrifugal advance = .462"
13L slot = 26 degrees centrifugal advance = .488"
14L slot = 28 degrees centrifugal advance = .514"
ETC.

 

[Kelly_H]

Do either of you guys have any links that show how to take it apart? I've pulled the distributor but I have no idea how to remove the cam from the body. I've found mention of a retaining clip but have no idea where it is. This seems like it's getting more and more dangerous for me to mess with by the minute! Good thing I'm in a tinkering mood...

From what I have found on Google it is also supposed to have C-clips on it but mine has push-on clips (which are apparently rusty and fragile, as I have just found out). Should I replace these with C-clips once I've inevitably mangled mine? Or do I need to find a similar push-on style replacement?

This is the only picture I've been able to find so far of cam removal:

Not sure what he's doing...

And yes, mine is a Motorcraft distributor. Bummer I didn't even think about mentioning it to anyone at Knott's - though that of course would have inevitably resulted in distributor parts strewn across the show grounds and a jillion people in my engine bay :lol:

 

[GT289]

He's prying gently up on the cam and using the small screwdriver to
remove the clip.

 

[Kelly_H]

Ah! Got it. The dizzy cam and weights are well overdue for cleaning, it appears. I suspect they are covered in bits of melted Pertronix (melted one last April when I left the key on... and I mean MELTED).

So here's another question: in your picture there are two pretty mangled yellow plastic bushing/clips that hold the weights down. Is there a source for that? Because mine are pretty much exactly as mangled and I doubt they're long for this world.

Thanks again for taking the time to help me out with this. I've learned a lot today!

 

[Paul1958]

Kelly,
The 13L/18L cam plate is correct for your C5OF-E distributor (not 15L)

In case you havent got the cam clip out yet (they can be a PITA) here is what it looks like out of the dist:
http://forums.vintage-mustang.com/5909233-post6.html

The cam weights and springs are interchangeable in location.

Paul

 

[Paul1958]

So here's another question: in your picture there are two pretty mangled yellow plastic bushing/clips that hold the weights down. Is there a source for that? Because mine are pretty much exactly as mangled and I doubt they're long for this world.

Kelly
Doesnt your C5OF-E distributor use steel E clips (not plastic) to retain the weights?:

Paul