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Total advance - HiPo distributor

24K views 67 replies 19 participants last post by  66TotalPerf 
#1 ·
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.
 
#2 · (Edited)
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.
 
#3 · (Edited)
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.
 
#5 ·
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.
 
#4 · (Edited)
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
 
#8 · (Edited)
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
 
#9 ·
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?
 
#11 ·
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
 
#12 ·
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.
 
#13 ·
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
 
#14 · (Edited)
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.
 
#15 ·
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.
 
#16 ·
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:
 
#17 ·
He's prying gently up on the cam and using the small screwdriver to
remove the clip.
 

Attachments

#18 ·
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!
 
#20 ·
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
 
#19 ·
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
 
#22 · (Edited)
Kelly,
If you really have a C5OF-E HiPo dist then somebody has swapped out your advance cam and weights as they did not use the plastic bushings back then. The weights for the old distributors like this are different from the weights used with later distributors with the plastic bushing/retainer - the hole in the weight is larger to accommodate the bushing. All 65-68 289 distributors - including 65-67 289 HIPO used the setup with no bushings.

Here are some pics from my original 1966 289 2Vs distributor. Note that when I disassembled this distributor tonight to photograph the advance weights and retaining clips it had not been apart since I purchased the engine in 1976 (and most likely never been apart ever). This engine has been on an engine stand in my garage since 1981 (dont ask):








No plastic bushing or space for one. The hole in the weight is just a slight clearance on the pivot pin:



Hope this helps
Paul
 

Attachments

#23 ·
Hmm! I see what you mean - on yours the posts are thicker for the weights to sit on without the bushing. Interesting, wonder what prompted PO to do that with mine. Doesn't really make sense, does it? I wonder if there is any benefit to putting on the later year weights?

It seems like it would be very difficult to reverse that though as I'd have to remove the entire assembly that the post is attached to (not sure what it's called) in order to put in the correct one. So I will leave it alone for now. But definitely something interesting to know! Thanks very much for taking the time to take your dizzy all apart so I could see pictures of what it's supposed to look like - I really appreciate it! :)

Whoever ends up rebuilding this thing in the future is going to be very perplexed I'm sure.
 
#26 ·
Which is why I didn't rebuild my own...to many variables..
 
#27 ·
Kelly,
The weight pivot pins are attached to a plate that is welded to the distributor main shaft. You need remove the distributor gear from the end of the shaft to remove the shaft from the housing. You would need to similarly tear down an old 'donor' 289 distributor for its shaft and swap out into your housing. Short of purchasing another HIPO distributor that is the only way I can think of if you want to keep your 289 HIPO housing. You could always put in a vintage 'plain jane' (no dis to Calamity) non-HIPO 289 distributor.

Paul
 
#28 ·
I think right now I would prefer to just put in the new bushings that I need and call it good. I see no reason that this plate shouldn't work just as well as the other if the only difference is the style of the pins that hold the weights. I am not a stickler for everything being 100% "correct" on my parts as long as they work properly. If this plate works just as well as the other then it'll be staying there until the distributor explodes!

I would like to clarify that right now I DO NOT have the money to replace a distributor, or have it rebuilt, or anything of that sort. I will not be changing the distributor. It worked before and it will be made to work for as long as it needs to.

Bart - are you referring to the rubber bumper on the "advance tab" (whatever it's called)? If so, I'm pretty sure that's supposed to be there... it is in all other pictures I've seen, at least.
 
#30 ·
Bart - are you referring to the rubber bumper on the "advance tab" (whatever it's called)? If so, I'm pretty sure that's supposed to be there... it is in all other pictures I've seen, at least.
Yep. That's the "poor man's" limiter. The "correct" ones are made of brass with ears that you crimp. A small piece of clear vinyl tubing (don't tell SWMBO why the fish tank air pump hose got a tad shorter) slipped on makes an effective limiter. If you don't have ENOUGH advance (my 5.0 is running 8* initial and the 18* side so 44* total) you can also file out the slot for a bit more.
 
#29 · (Edited)
What I have found is most all engines want more initial and less total. Its because fuel burns differently today. Most want close to 20* initial and total of 32 to 36*. Now if you have EGR vacuum advance can allow its added advance to increase 10 to 15*. Without EGR closer to 2 to 5* more at best.

PS last I looked points for HIPO dizzys were not avilable but other Ford dual points were and are not quite the same.
I have a really nice hipo dizzy removed and stored over 40 years ago ready to go except points
 
#36 ·
Not sure you read the entire thread.

Its not the pivots that are wearing out. Kelly said that her distributor has the weight setup that uses the plastic bushings/retainers and hers are breaking/broken. I am not certain if you can still get those plastic retainers so I suggested an alternate solution whereby she retrofits the earlier distributor shaft and weights that just use the E clip retainers into her HIPO dist housing. I was actually surprised that her HIPO distributor has the later plastic bushing/retainer setup. At least that is my understanding of the situation.

Paul
 
#37 ·
Right you are Paul - thanks for the summary! I have no earthly idea why the PO put the later setup into the HiPo dizzy. Most things the PO of this car actually did for a reason (surprising, I know) so I am inclined to just let it be.

Fortunately I think I've found a source for those bushings. If not, I will go spelunking in a junkyard and see if they'll let me just take those parts. Once I've got them in hand I will pop them on and everything will hopefully be right as rain! :)

Assuming that everything on the dizzy then works properly, I may get those lighter springs that Zray recommended to replace the one heavy spring on mine. It would be interesting to see how that changes the car's behavior. It is already quite zippy ;)
 
#39 ·
Right you are Paul - thanks for the summary! I have no earthly idea why th

Fortunately I think I've found a source for those bushings. If not, I will go spelunking in a junkyard and see if they'll let me just take those parts. Once I've got them in hand I will pop them on and everything will hopefully be right as rain! :)
Kelly,
If you do go junkyarding you want to look for 302s in mid/late70s very early 80s Fords. Starting in 73 Ford went to the 'Duraspark' ignition setup. The Duraspark distributor was used 73-85 and used the same basic advance cam/weights/springs setup as he earlier points distributors but should have the weights with the plastic bushing/retainers you need.

To get to the stuff you need you will need to remove the reluctor (8 toothed wheel) and the breaker plate the magnetic pickup is mounted to. Very easy with standard hand tools:




Two screw drivers to pry up the reluctor


Then two screws and one tiny E clip to remove the vacuum advance diaphram:



Then two phillips head screws at the breaker plate/magnetic pickup:


And there will be your bushings/retainers:


You will want to GENTLY pry them off the pivot pins.

Good luck (boy this really takes me back to the early 80s!!)
Paul
 
#41 · (Edited)
Paul - thanks for those awesome instructions! I will see if I can go spelunking in a junkyard soon. I had a friend who had a couple of these distributors laying around and he tried to pull the bushings for me but they shattered. Not sure if there's a trick to it or if they just get super brittle when they get old.

At any rate, I know I'm going to get disapproval by the bucket for this one, but I need my car back on the road and at minimal cost. So I went to my local hardware store and picked up whatever I could find that would work. I ended up reusing the plastic bushing minus the flange (since the flange was the only part that shattered). So basically it's just a plastic sleeve. Lubed it up with lithium grease, stuck it in the advance weight, put the advance weight onto its post, and then added two appropriately sized washers. Then used an E-clip at the top of the post as a substitute for the "teeth" that held the bushing in place. I've jiggled it very thoroughly and it seems to actually have less up and down movement now than it did before, though it retains 100% ease of side to side movement with no resistance whatsoever. Doesn't seem at all inclined to go anywhere. I'm quite pleased with myself!

Here's some pics. As a refresher so that you guys remember how disgusting this thing was, the first pic is of it pre-cleaning after removing some parts:


And now post-cleaning showing my jury-rigged solution:





Oh, and to clarify on the positioning of the washers: the washer at the top of the stack is actually exactly the right size so it slips over the top of the post but won't go further than where it is in the picture. So it is being used as a shim to take up the slack so the E-clip sits firmly in its slot. The washer at the bottom of the stack is actually not quite contacting the upper washer - it is very close though.
 
#43 ·
Kelly,
That looks like a great fix and as long as the E clips fit tightly - and it looks like they do - you will be fine. Great thinking!!

BTW
Plastic can become very brittle with age and heat cycling - especially plastics from the 1970s which lacked the heat stabilizers that are used nowadays.

Paul
 
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