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Thread: Need help understanding timing specs

  1. #1
    President Member wdills's Avatar
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    Need help understanding timing specs

    Let me start by saying that I am not good at engine tuning. I also may be expecting more than my 259 can deliver. Everything is new, fresh rebuilt 259 engine, Dave T-bow rebuilt WCFB and Mallory distributor, new wires, plugs, etc. Engine starts easy and idles and runs nice and smooth.

    My current problem is coming off idle. It doesn't want to accelerate if I open the throttle quickly. It will stumble and backfire through the carb every time. I thought I may have a problem with timing or advance so I checked it all this morning. I will describe what I found in a lot of detail, because I am not sure if I am interpreting the factory spec's correctly.

    I started by disconnecting the vacuum line from the carb and plugging it.
    Warmed up the engine and set idle to 600 RPM.
    Checked timing and it was right on the ignition mark. I understand that this means 4 deg advance. Timing light was showing 0 deg advance.
    I accelerated the engine to 2500 RPM and measure timing again. To bring the IGN mark back to the pointer I had to adjust the timing light to 19 deg. Centtrifugal only advance is supposed to be 22-26 degrees according to the specs.
    Here is my first question, Do I add the 19 degrees measured on the timing light to the initial 4 deg for an actual centrifugal advance of 23 deg which is within spec or was I supposed to read 22-26 degrees on the timing light
    Next step was to check vacuum advance. I had a vac pump connected to the vacuum advance. Engine back at 600 rpm idle.
    Up to about 9" vac I got 0 advance.
    At 11" vac I had 4 deg advance on the timing light.
    At 12" vac I had 11 deg advance on the timing light.
    At 15" vac I had 15 deg advance on the timing light.
    I stopped at 15 because that is the amount of vacuum I am getting at the intake manifold at 600 rpm
    So the Vac advance numbers seem to be pretty close to spec without adding the initial 4 deg.
    Once all that was done I adjusted the idle mixture to the best of my ability. Both screws ended up between 1 and 1.25 turns open.
    Engine will still stumble and backfire if accelerated quickly.

    Took it for a test drive and the performance is un-inspiring. I can mat the throttle, the OD will kick out and it will begin to accelerate but there is no set you back in your seat acceleration going on. Maybe the 259 is not capable of that type acceleration, I have no frame of reference for comparison. I would hate to get in a race with the wife's 130 Hp Hyundia Accent.

    So, are my advance numbers ok or do I need to make some adjustments to the vac advance?
    Am I expecting to much as far as engine power and performance for this stock 259?
    Wayne
    "Trying to shed my CASO ways"


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    Sorry, I'm used to using a timing light without any built in "adjustments". I'd simply set the gun to zero, and set as per the manual-they didn't have fancy timing lights. The pointer on the cover, and marks on the damper must be right, but can be checked that TDC is actually TDC on the marks. Go from there- the vacuum advance should only be checked for max timing input--that is at anything over 13 in it should show the maximum amount built in. There really isn't any "curve" in the vacuum controller, just de-advances as vacuum falls, not very important for max power-engine will put out max power when it's disconnected entirely, it just won't run very well under light loads. As to performance- have you driven or ridden in another Stude with similar engine/trans combination? Yes, your Hyundai may be faster, and more fuel efficient. For comparison, read some road tests of the 50's and 60's for real numbers- a supercharged Avanti was considered quick at 7.0 seconds 0-60. Most economy cars of today unless set up to get 40 MPG will easily beat that-or come close. But they sure aren't as cool looking.

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    wdills;
    Your timing sounds good to me. I do believe you add the 19 degrees you got to the 4 degrees advance to get total advance. The vacuum advance should be connected to the carburetor and not to the intake manifold vacuum source.
    As for the stumble; it sounds to me that the accelerator pump is not adjusted correctly or not working at all. Remove the air cleaner and without the engine running look down the carburetor and see if you see a good stream of gas as you open the throttle. The stream should start as you first start to move the throttle.
    Ron

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    President Member wdills's Avatar
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    Is there a max amount of advance that should be generated by the vacuum advance? I know that at 15" my advance was more than the highest value in the spec I have. I also know that when I went above 15" my advance went even higher. I can adjust it down if there is a max amount I should stay below.

    Vacuum advance is connected to the carb. I just had a vacuum gauge connected to the manifold for reference. The accelerator pump works good with a nice shot of gas as I open the throttle.

    I am more concerned by the stumble and backfire coming off idle. I am not as worried by the amount of power, just not what I expected. And no, I have never driven another 259 / T86 OD car for comparison. In fact the only other Stude I have driven is Dad's 50 Starlite 170 / T86 OD. Thankfully my Hawk makes more power than his Champion.
    Wayne
    "Trying to shed my CASO ways"


  5. #5
    Zero on an adjustable timing light means (in a perfect world) that the damper marker 0 point aligns with the pencil pointer. That is TDC for the piston. If the spark were to occur at that moment the timing would be at 0 degrees. Your IGN line is valid ONLY for a standard timing light. So if your total timing on your adjustable light is reading 19 degrees when you dial the damper TDC 0 mark back to the pencil pointer then the total timing with no vacumn advance is what the dial reads (19 degrees). So you want this 23-26 reading to occur on the dial when you advance the distributor clockwise to line up again that TDC marker 0 on the damper with the pencil pointer. I would recommend at least 26 degrees total minimum. And if you want more power zip then go for 28-30 total mechanical advance. You have low compression and it needs some advance to have some zip. If I raced using factory timing specs I would never win. Set your idle up to around 750 also. Get the air speed moving faster through the carb so that the carb can get some decent plenum signaling from the engine. A 259 is a good engine when tuned and every thing is top notch. Good luck.
    Last edited by 11SecAvanti; 10-02-2016 at 01:31 AM.
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    Graduate back yard mechanic, I would put the timing light in my back pocket for now. Line up the timing mark at top dead center by turning the fan, also confirm it is number one. Remove the distributor cap and rotate the distributor until the points just start to open. That will put you at top dead center, now turn the distributor just a hair counter clockwise and re-tighten it. Recheck the position of the pointer at the timing mark and it should read at four degrees retarded. The moment the engine starts it will advance to just before top dead center and you shouldn't have to do any more than that. Another back yard test is to suck on the vac unit and put your tongue over the hole and it should hold the vacuum indefinitely, if it bleeds off the unit is faulty. When powering up a hill the vac advance becomes unserviceable and the centrifugal system takes over. The advance weights are inefficient at low speeds and the engine relies on the vacuum system for the required advance.

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    What is your vacuum reading at warm idle? sounding a bit like you need a valve adj. session. set them a little loose .026/.027 for now and drive a little. you should just hear a little valve noise with hood open.if there is no tapping their to tite. Gotta love those solid's! Luck Doofus

  8. #8
    Congratulations for daring to get so mechanically involved. Stick with it, and the financial and emotional rewards are many.

    How old is the gasoline in the tank?
    I'd catch a sample in a clean glass container when I was checking the fuel pump delivery, just before checking the fuel pressure.
    It should be clean, have a distinctly sharp odor, not be the slightest bit murky or cloudy, and not get any clearer a minute after a splash of ISO dry gas is added.

    This page looks to be from a Motors manual. FWIW It claims 18-20 inches of vacuum at idle.
    https://restorecarsclassifieds.com/wi...df.pdf?n=12794
    I'd still check the valve clearance.

    On most carbs The idle mixture setting affects the mixture at very small throttle openings to some extent too.
    I'd back them out a bit for highest smooth idle and give that at try.

  9. #9
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    As with all of my technical responses, I offer this caveat: I am new to the world of Studebakers, but have lots of experience with auto repair and maintenance in general. So.. if there is some Studebaker specific reason my methods won't work on a Studebaker, I would defer to Jack V., Rich, Skip, Fred, or any number of guys who are light years ahead of me when it comes to Studebakers.

    I don't think it matters, but just to be sure, what year of 259 are we talking about? I have Sun tune up cards for every year from 56 forward, and believe they are all the same specs., apparently even for 8.3:1 compression, 7.5:1 compression and 7.0:1 compression, which makes little sense to me, but from a bean counter standpoint, would be nice, as different distributors and different vac advance cams would not be required, meaning it is cheaper to make them that way. HMMMM, maybe that is where the CASO dna came from... Studebaker bean counters? I will try to post a pic of the 1958 259 specs with this post, but have had some issues posting pics lately.

    Sounds like you have a couple issues. One may be timing, but the other appears to be a lean misfire. As was addressed by rstrasser: "As for the stumble; it sounds to me that the accelerator pump is not adjusted correctly or not working at all." As Dan indicated, you can HELP that lean misfire just a bit by backing the idle screws out slightly. But really, that is more of a patch than a cure. It ought to transition from idle smoothly, and the accel pump makes that happen. So, for the stumble & backfire, make sure you have a good accel pump shot.

    As for the general lack of power, here is my two cents on the timing. According to the attached tune up card (and the specs as you read them) initial timing is set at 4 degrees at 600 RPM. But, the mechanical starts coming in as early as 700 RPM (remember, engine speed is 2X distributor speed). Doesn't have to be far off to start messing with your initial setting. I am a firm believer that what matters MOST is the TOTAL of initial and mechanical. I have never seen an old school engine (pre-1970) that didn't run best (i.e. best combination of power and economy) at anything less than total timing of 32 to 34 degrees, and many at even higher such as 36 to 38 degrees. When I reference "TOTAL" timing, I am including ONLY initial and mechanical. Yes, I realize the absurdity of using the word "total" while excluding one of the parameters that contributes to advance.... that's just the terminology as it has come to be used in the performance world, so I will stick with it). Apparently, your mechanical advance is "all in" before 2500 RPM (maybe as early as 2250). I will get to the vac in a minute.

    You have the advantage of a dial back timing light. Plug the vac advance, and rev it to 2500 rpm and set the total timing at 34 degrees. That is a good start. Now, if you want to see where your initial is (like I said I don't believe it is all that important in the grand scheme, but you may want to set timing after replacing points and make a note of where your initial is set on this engine for future reference, so you don't have to reset it by revving the engine each time).

    Now, plug the vac advance in to a manifold source. It will be a non factor when under a heavy load, but will give plenty of advance when cruising under very light throttle. Adjust your idle back down (it will surely have increased) to 600 to 650, & adjust your idle mixture. I would guess your engine can take another 15 degrees of advance via the vac advance, but if that presents a problem, you can adjust it with washers, right?

    Take it for a drive (no radio) and listen very carefully for any pinging sound (if you never heard pinging, it sounds like a bunch of marbles rattling around in a tin can). There will be naysayers who will point out that an engine may be pinging slightly but not be audible. Yes, possible, but mostly not doing damage if it is inaudible. If you want to be sure, but INCREASE the timing a bit more and drive it until you DO hear it ping, then back it off back to the 34 degree total.

    Here is a link to a good article written by a friend of mine who worked for GM during the 60's and 70's. It helps explain the overall picture of mechanical and vac advance. It has no relevance on today's computer controlled vehicles, but applies to old engines. https://www.camaros.net/forums/13-per...nce-101-a.html

    And finally, here is a pic of the 1958 Sun Tune up card.

    Click image for larger version. 

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    BTW, I have tune up cards for almost every American engine from 1956 through 1966. If any of you guys want a copy front and back (you won't get one of my original cards, but I don't mind making a copy for you) just send me a PM. I will be glad to copy front and back (where applicable... some are blank on back) and mail it to you.
    Last edited by Lynn; 10-03-2016 at 01:28 AM.

  10. #10
    Hi Lynn.

    Is JohnZ still around ? I have a couple of questions I've been meaning to ask him for some time now.

    thanks,

    Dan T

  11. #11
    President Member E. Davis's Avatar
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    Interesting article Lynn. I have always wondered about the wisdom and value of the ported system as opposed to full manifold vac and didn't realize it was an early "emission" control device. It will also be interesting to see what others think about this.

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    I believe John is still around. Active in NCRS.

    Will look for his email and send you a PM.

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    One other thing to check: make sure the copper braid ground wire from the breaker plate to the inside of the distributor body is intact and not frayed, and likewise the "pigtail" from the points to the grommet in the body, and thence to the coil is intact and not frayed. There is constant movement of that breaker plate, and both those wires can fatigue and fail, in which case the movement of the breaker plate due to change of vacuum when the throttle is opened can cause a transient miss.
    Gord Richmond, within Weasel range of the Alberta Badlands

  14. #14
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    Quote Originally Posted by gordr View Post
    One other thing to check: make sure the copper braid ground wire from the breaker plate to the inside of the distributor body is intact and not frayed, and likewise the "pigtail" from the points to the grommet in the body, and thence to the coil is intact and not frayed. There is constant movement of that breaker plate, and both those wires can fatigue and fail, in which case the movement of the breaker plate due to change of vacuum when the throttle is opened can cause a transient miss.
    Good advice, Gord, for anyone who's tuning the old junk, but IRRC, Wayne has a new Thibault Mallory distributor.

    jack vines
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    E.Davis and others
    All I know about vacuum advance is that on my Avanti that is in the garage at my house has its original AFB and the Vacuum advance unit is connected to the Carburetor and not to manifold vacuum. When I put a vacuum gauge on the port that the vacuum advance is connected with the engine at idle speed (about 600 RPM) there is little to no vacuum at the port. As I increase the engine RPM the vacuum at the vacuum advance port increases. Once I am up to around 1500 RPM with no load on the engine the vacuum gauge reads the same at either the carburetor port or the manifold vacuum. Even though the engine vacuum (on the factory gauge is low) it is still around 12 inches or so at idle. Have not had the ambition to see if there is a leak as the car runs very well. And the thought of trying to get at the back of the factory vacuum gauge is not something that i look forward to.
    Call the port that the vacuum advance is connected to what you want but it is not at engine vacuum.
    Yes I read the GM fellows article; It just doesn't agree with what I have observed on Studebakers..
    I previously checked my other Avanti that has a Elderbrock on it and I have it connected the same way. The other port on the Elderbrock is at manifold vacuum.
    I do vaguely remember that some cars; after I was out of working in a tune up shop had full vacuum going to the vacuum advance unit at idle speed
    Ron

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    I don't doubt it for a minute Ron. I wasn't trying to say that no car ever used ported vacuum to the vac advance before emissions requirements. That is also one part of the JohnZ article with which I disagree. I don't believe it was ONLY emissions requirements that started the experiment with ported vac. I believe it started earlier, and if your car is hooked up that way from the factory, that would be a good example.

    However, my experience is that using manifold vacuum allows a little more spark for cruising, which normally results in better economy. It also allows for more aggressive timing through the midrange during brisk acceleration, mainly because the manifold vac to the vac advance goes to zero under load.

  17. #17
    That is one of the statements I'd like to ask John about.
    I think the wording is not quite accurate.

    That is Not to say VA was NOT used for specific emissions reasons.

    Attached is an image from a Chevy factory shop manual.
    The description sure sounds like ported vacuum.
    In 1951 i don't think emissions were on many people's minds.

    There are a lot more examples of ported vacuum being pretty popular long before the emissions era.
    I think one advantage can be steadier idle speed, since the ignition timing isn't changing with manifold vac changes.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  18. #18
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    Geeze i Love this S@#t!!! you havent lived till you have revved (Foot Tuned) an R1 with 50 degrees Total timing. an accident but it ran smooth till you tapped the accel. pedal then engine went stratospheric!! Awsome but sanity set in when it wouldnt crank. yes it survived. Doofus PS Boss sure came running out at cam breakin time!!!

  19. #19
    President Member wdills's Avatar
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    I made a few checks yesterday before readings all these responses. One thing I noticed is that I am not getting any advance at idle. I thought the Vacuum connection on the WCFB was full manifold vacuum. Based on the lack of advance I am assuming that it is ported vacuum or I have a problem with the vacuum line. Which is it supposed to be, ported or full.

    As for some of the other questions, here is what I can answer now. Warm manifold vacuum is 15" at idle (650 rpm). Car has a fresh tank of 89 octane non-ethanol gas. I have gone through the valves twice, they are set at .026" cold.

    I know the specs call for 18-20 inches of vacuum. I guess I will check for a leak tonight. The car runs so smooth, I didn't expect a vacuum leak.
    Wayne
    "Trying to shed my CASO ways"


  20. #20
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    The WCFB vacuum port is direct, I believe. Use of ported vacuum didn't show up till they were long out of production. Follow the inlet tube passage into the throttle bore. If it comes out below the closed butterfly it's direct. If you have to move the butterfly to uncover it, its ported Since you are using a Mallory distributor verses stock, you might have to check the maximum advance of the vacuum can, it may be too much. If it is giving you more than 8-10 crank degrees at 13" then you'll need to back it off (reset the limit) I believe a 3/32 allen wrench placed in the tube for the vacuum hose, will engage an adjusting screw, and can adjust the maximum, if it's a Mallory advance unit " The vacuum advance is FULLY ADJUSTABLE with a 3/32" allen key in the vacuum port to adjust the vacuum diaphragm, and you set it according to vacuum measurements you get from your carb(s). This means it doesn't matter what carb(s) you have, and it also doesn't matter what cam you are running! While other guys are running 30 degrees of full advance, you will be cruising around at 42 degrees". That is from a Mallory description. Sounds great but if your engine can't handle that amount of timing-you'll have to adjust it down. Before going any further, I'd call Dave and ask what curve he installed in your distributor, or if its pure Mallory. He usually sets them up for R1, R2 curves and maybe yours isn't right for your 259 ask him. Popping at tip in usually means firing with the intake valve not closed, ie. too soon, too much advance. Playing with the mechanical advance setting won't fix it, you'll get it right without vac advance but then have too much at idle , if it gives you 15 crank degrees or more. If you rotate the distributor to lower that, you'll have the wrong mechanical at 1600 RPM regardless of vacuum reading at that RPM.
    Last edited by karterfred88; 10-03-2016 at 12:22 PM.

  21. #21
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    Look in the carburetor to see if the accelerator pump is working!

  22. #22
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    Accelerator pump works fine. Nice shot of gas when the throttle is opened.

    Sounds like I have a problem with the WCFB vacuum port or the vacuum line from the carb to the distributor. I know the advance works by testing it with a vacuum pump. But I don't get any advance at idle when I have 15" of manifold vacuum. So if the WCFB has a full (direct) vacuum port, something must be plugged up.
    Wayne
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  23. #23
    President Member E. Davis's Avatar
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    Quote Originally Posted by wdills View Post
    I made a few checks yesterday before readings all these responses. One thing I noticed is that I am not getting any advance at idle. I thought the Vacuum connection on the WCFB was full manifold vacuum. Based on the lack of advance I am assuming that it is ported vacuum or I have a problem with the vacuum line. Which is it supposed to be, ported or full.

    As for some of the other questions, here is what I can answer now. Warm manifold vacuum is 15" at idle (650 rpm). Car has a fresh tank of 89 octane non-ethanol gas. I have gone through the valves twice, they are set at .026" cold.

    I know the specs call for 18-20 inches of vacuum. I guess I will check for a leak tonight. The car runs so smooth, I didn't expect a vacuum leak.
    Although specs call for 18 to 20 inches of vacuum remember that those readings are for sea level. I don't know the elevation in the area where you live but you will need to deduct one inch of vac (or one graduation on the gauge for each 1000 feet of elevation above sea level.

  24. #24
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    Wdills;
    Connect a vacuum gauge to the vacuum port on the carburetor. You should see the vacuum gauge go from about 0 at idle to 15 or more inches of vacuum as you increase the engine speed. If it does, as I believe it will, you have ported vacuum at the carburetor.
    As i said earlier I know of no pre 60's car with manifold vacuum going to the vacuum advance unit on a distributor. Not saying there is not, I just don't know of one.
    Ron

  25. #25
    I know the carb has been rebuilt, but check your float level.

  26. #26
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    I ran across this WCFB reference, which seems to indicate on at least 1956 cars the port is ported (by description). How that affect your engine set up, I don't know-on Avanti R1-R2 with AFBs it is not.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  27. #27
    President Member wdills's Avatar
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    Just when I thought I was understanding timing lingo, I get lost once again. I just talked to Dave T-bow and confirmed that the WCFB vacuum port is ported. So the vacuum advance doesn't do anything at idle it only works at higher rpm when the throttle plates are open. The post by Lynn made perfect sense when I thought the WCFB had manifold vacuum, but since it is a ported vacuum it seems the vacuum advance has to be part of the total advance.

    So now lets get back to the lingo with reference to the Sun tuning sheet posted by Lynn.
    I have seen the terms static and initial advance. They seem to mean the same thing. That is vac advance line plugged and timing set for 4 degs which means it is on the IGN mark. Please confirm if I am correct.

    Next on the SUN sheet is cent only advance of 22-26 deg. I think this means I bring the RPM up until the timing mark stops moving and then take a reading to the UDC mark. Am I correct?

    Finally is Total Advance which the SUN sheet says should be 36 - 44 deg. I thought this meant I should add the cent advance that I just measured to the max amount of advance I get from my vacuum advance pot. The problem is the SUN sheet shows a vacuum advance in distributor degrees which I believe are 1/2 of crankshaft degrees. Is this correct? This would mean my max vacuum advance at 10.25-11.5" would give 14-18 deg advance on the damper timing marks.

    Thanks for your patience.
    Wayne
    "Trying to shed my CASO ways"


  28. #28
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    wdills;
    The tune up sheets were written for the days when a distributor was set up on a Sun or equal distributor machine. Multiply the distributor degrees by 2 to get engine degrees.
    Yes when you add 18 max vacuum to 26 mechanical you end up with 44 degrees total advance at the crankshaft. Vacuum advance is for fuel economy not performance; why worry about it. Disconnect it and plug the port.
    Advance the distributor until the car runs best while accelerating without pinging. After that connect the vacuum advance and adjust as needed or leave it disconnected. If you want economy purchase a new small car.
    Ron

  29. #29
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    Although I understand the desire to "mimic" original specifications, you don't have original equipment. Using SUN specs as mentioned is for an original distributor on a distributor machine. I'm afraid the best method here is the try and retry method, find what works best by adjusting both the mechanical advance to work as mentioned, then playing with the vacuum advance adjustments till it works the best for you. If it "pops" on initial tip in, try slowing down the vacuum advance by increasing the diaphragm pressure. If it "pops" with out it connected back off the initial timing. If you wind up with too much total at that setting and it pings, recurve the distributor to lower the total. Isn't this fun? And you thought there was an answer, didn't you??

  30. #30
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    Ok, I think I finally understand how all the various pieces of timing fit together. Here is what I did tonight. If I am doing something wrong here, please let me know.

    I plugged of the vacuum advance line and verified initial timing was 4 deg (IGN mark) at idle.
    Accelerated the engine up to 3000 and then 3500 to be sure I was measuring all of the mechanical advance. It stopped increasing at 3000 rpm at 28.5 deg from the UDC mark.
    So this tells me the mechanical only advance is 24.5 deg max
    Back at idle I hooked the vacuum pump back up the the vacuum advance and took it all the way up to 20". It stopped increasing around 16" at 17 deg at the crankshaft.

    Since everyone seems to agree that 34 deg total (static plus mechanical) is a good place to be, I reset the initial to 10 deg, so this should give me 34.5 deg total. I didn't adjust the vacuum advance because it was already within the 14-18 deg (at the crankshaft) spec. I also set the idle up to 700 rpm and verified I wasn't getting any mechanical advance at that speed.

    It now has good off idle response. It revs right up with no stumble or backfire. Drove it down the road. Didn't hear any strange noises and it responded well to the throttle. Still not a power house but better than it was. I knew I was going to give up some power when I chose to have a 259 built instead of a 289, so I guess the performance is what it is. At least it now has enough power and throttle response where I feel confident driving it. Before I was hesitant to pull out into traffic.

    I still have to search and see if I have a vacuum leak since I only have 15" of manifold vacuum at idle. A project for another day.

    So any problem with what I did or the settings I ended up with?
    Wayne
    "Trying to shed my CASO ways"


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    Great. Some engines don't make much more than 15 inches vac at idle. You may not even have a leak.

  32. #32
    Yes, keep the base initial timing in the 10 to 14 degree range. I run 15 with no issues on my clone Super Lark with modified total advance. That should put the total mechanical advance in the 34-36 maybe 38 range on your dist. Test drive and retest. Listen for ping under heavy load etc. It's not that difficulty. Just monitor your changes and go with the better settings.

    As for the low vac. if it is not a carb or manifold leak then it could be a valve seat not sealing or just further tuning is needed on the carb. I suspect the carb idle adjustment screws area. I see 18 vac on a test stand 259 engine here. Silky smooth idle. You need to add an A/F meter to this engine too. Well worth the time and money believe me. Good luck. The car is beautiful by the way.
    Start and Stage Your Studebakers

  33. #33
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    Sounds like you have conquered it!! I would drive it and break it in correctly (old school) it may improve on performance as everything wears in-good luck--have fun.

  34. #34
    Silver Hawk Member 52-fan's Avatar
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    I just read this whole post hoping you found a solution. I have a 259 with an Edelbrock 500 CFM carb in my Commander that right now has no vacuum advance and it pulls strong. Maybe not a powerhouse, but it still makes me smile. I have wondered if Tom (11SecAvanti) helped Leonard do a little something to this engine.


    "In the heart of Arkansas."
    Searcy, Arkansas
    1952 Commander 2 door. Really fine 259.

  35. #35
    Yes, I adjusted the valves in my driveway, fiddled with the air mixtures, and bumped the timing up above the pitiful factory 4 degree mark. We went for a ride and I blew all the soot out in the gears. Lenny went home happy! Did I forget to reconnect the vacuum? Can't remember. That's a Pure Stock 259.

    I miss you Lenny. Gone but not forgotten.
    Start and Stage Your Studebakers

  36. #36
    Silver Hawk Member 52-fan's Avatar
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    Nope, you didn't forget the vacuum advance. The diaphragm was no good when I got the car. That was probably the main reason Leonard's son couldn't get the car to run before he sold it. I am going to replace that distributor with a good two piece one. The short one was rubbing the firewall when I got the car and after shimming the bell housing mount I have less than an 1/8 clearance. The taller one will fit the firewall recess.


    "In the heart of Arkansas."
    Searcy, Arkansas
    1952 Commander 2 door. Really fine 259.

  37. #37
    President Member mapman's Avatar
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    Wow! What a timely thread. I am working on my Avanti now trying to get it sorted out. It was an R2 and still has the block and heads intact but no supercharger, it has an R1 carb and I just replaced the bad R2 distributor with an R1. Reading the manuals I was trying to figure out how to determine the timing but this should work. The vacuum had dropped below 10 at idle but it ran very well at speed but idles terrible. l have some more things to finish before I can test this out but I have a plan now. Thanks
    Rob

  38. #38
    President Member starliner62's Avatar
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    My experience with 259 engines is that they like a lot of timing. Mine is also set at 15 degrees. No detonation and good performance. At 4 degrees, the engine sounded lazy.
    Jamie McLeod
    Hope Mills, NC

    1963 Lark "Ugly Betty"
    1958 Commander "Christine"

  39. #39
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    Quote Originally Posted by mapman View Post
    Wow! What a timely thread. I am working on my Avanti now trying to get it sorted out. It was an R2 and still has the block and heads intact but no supercharger, it has an R1 carb and I just replaced the bad R2 distributor with an R1. Reading the manuals I was trying to figure out how to determine the timing but this should work. The vacuum had dropped below 10 at idle but it ran very well at speed but idles terrible. l have some more things to finish before I can test this out but I have a plan now. Thanks
    Rob
    You'll need to fix the very low idle vacuum first, of course. Since you will be working with a much lower compression than the R1 (9.5 vs 11.0) timing will differ from the original regardless of which distributor and carb you are using. I'd start by replacing the intake gaskets, after doing a leak down test. If you have bad valve sealing it will never run right. But if that's okay, valve adjustment and timing may bring the vacuum up. Good luck!!

  40. #40
    President Member mapman's Avatar
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    I think the bad distributor was causing some of the vacuum loss. I am replacing the water pump, the fan and viscous coupler to get it back to stock. It had a small pulley on that was apparently part of a cooling package and a big aluminum 6 blade that sounded like a jet taking off. It has an original A/C now which replaced the supercharger some time in its history so I won't be getting completely back to stock. I checked the valve clearance and it was all right on. Once I get it running I'll check for vacuum leaks. It has 165-170 PSI in all cylinders. Eventually I will convert to pertronics as I lost 2 sets of points coming back from Kansas City (same set 500 miles apart). One set lost the the rubbing block, the other had the rivets pull out. It shut down on the highway both times. A good reason not to drive after dark.
    Rob

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