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charley norton
08-02-2006, 07:10 AM
Is there any method of ear timing a 289? I've tried it by the book and still have a lot of pinging as well as the temp rising slightly above 180 if engine stays under load too long. Better gas (105 octane racing fuel)helps but there must be a better way. I also may be getting too much advance. Is there a perfect amount of advance I can set it to? I think mine is at around 32 deg. total advance right now. I also thought I may be a little lean. The carb is the original 3507s. Is there a jet size other than the original that I should try and where can I find them? I've never set the valve lash and would rather not, but will if there is a chance that could be causing this problem. Would that be a good idea?
Charley

63 R2 Avanti

1956 Hawk
08-02-2006, 11:54 AM
The stock timing curve works perfectly in my R2 with 9.5-1 compression and 91 octane gas. You might want to richen up the secondaries a lot in your carb. Mine will ping like crazy if it goes even slightly lean. The Carter AFB uses the same metering rods and jets as the new Edelbrock carbs, so you can go to any local speed shop or auto parts store, or order them on line from Summit. By the way it takes a large change in jet size to make a difference in the secondaries, so I would suggest trying some jets around .110 in size. You can richen the carb by changing the metering rods, but this will effect your gas milage.
I wouldn't worry about a temperature of 180. You should be fine as long as it stays under 200.
Also adjusting the valves isn't bad if you do it cold. Hot is suppose to be better, but I don't thing it's worth the effort.
David

wagone
08-02-2006, 12:34 PM
I agree with David on valve adjustment--it isn't worth the effort to do it hot and idling. Set them .026" or .027" cold and as long as the cam lobe is on the base circle it will be fine. If I recall correctly the harmonic balancer has each 90 degrees of rotation marked on it which makes staying on the base circle a cinch. My '63 R2 has 9.00 to 1 compression and has never exhibited any detonation. I have rejeted my carb (3507S) and gone a little leaner than the factory (an R2--mine anyway--gets pretty horrendous gas mileage with 3.73 gears) and I have never noticed any spark knock, but I'm not sure the gas mileage is any better. Unfortunately I can't recall what size jets I installed, but I've still got the bill so if you are interested I can call Summit and they will tell me what diameter they are. They carry Summit part number 1427 and 1424 and hence it would be a simple matter to find the diameter. The primary rods I used are Summit number 1452. I believe it is still a little on the rich side and like I say the gas mileage could put a person in the poor house at $3.00 plus per gallon for what is marketted as 92-93 octane. I always try and use BP Ultimate. Check back if you want and I'll call summit and get the diameters of the rods and jets. Do you have the factory shop manual or similar? With the vacuum disconnected the centrifugal and initial advance should total 24 degrees at 1600 rpm. I'd make sure that is right before condemning the carb or valves (but adjusting the valves is never a bad idea with solid lifters). Might you have excessive carbon deposits in the cylinders--does it ever diesel when you shut it off when the idle is down where it should be and the engine is not overheated? You live in the south right? With today's fuel all bets are off on a hot day, I should think. In 100 degree weather a lot of old cars are going to suffer.

PackardV8
08-02-2006, 02:39 PM
Hi, Charley,

Things to check which can affect your problem.

1. PCV system operating correctly
2. Intake manifold vacuum leaks, including the line to the vacuum gauge and the power brakes
3. Exhaust heat riser valve - most are stuck - just make sure yours is open.
4. Think about blocking off the exhaust heat riser to the intake manifold. Two thin staniless steel plates will do it.
5. Know it isn't fun, but you have to know the valve adjustment is correct
6. and the ignition - plugs,wires, cap, rotor, points and condensor are new or verified up to spec. Have seen a lot of Avanti pinging problems actually be old wires crossfiring under the shielding, an old cap with carbon tracking, dual points incorrectly set, worn advance weight pivots allowing bad things to happen under there.

Bottom line, See JDPs wisdom on the subject - the car will sell at a much higher price than the cost of the above if you can verify it has had a major tuneup and running perfectly.

thnx, jv.



PackardV8

Mike Van Veghten
08-02-2006, 03:23 PM
Valve lash.....a must in the world of Studebakers.
Since they are of the mechanical design, youl'd better get used to it, or pay some one to check them every few thousand miles (3000 to 4000).

As one of the others said, cold works just fine. Engine not running. Despite what some will say, it's near impossible to get a good adjustment with the engine running. In the Stude manuals, there is instructions for doing it cold.

Mike

N8N
08-02-2006, 04:46 PM
Make sure that the advance mechanism is in good shape, too... the Avanti distributor was just a dual-point adaptation of the old single point Prestolite that Stude lovers love to hate. Good news is that I'm told that swapping in parts from a B/RB MoPar (which is the same basic design, but without the shortcomings of the Studebaker version) will yield an advance curve pretty close to R1 specs so it can be fine tuned from there, or just give the whole mess to a guy that has a distributor machine and knows how to use it and point to it and say "distributor. Fix." :)

Dave Thibeault sells new weights with Oilite bushings in them, which is the main problem with these units, but make sure your pivot pins aren't worn as well. If your car has high miles the dist. shaft bushings might be worn as well, and if you're in there, now is the time to fix 'em. Dave T. swears that when properly rebuilt the Prestolite has more stable timing than a Delco, but the problem is they really do need some modifications (see Oilite bushings above) otherwise they wear out incredibly fast. So given the choice between a NOS distributor and a properly rebuilt one, I would actually choose the rebuilt.

good luck,

nate

--
55 Commander Starlight
http://home.comcast.net/~njnagel

53k
08-02-2006, 05:00 PM
quote:Originally posted by charley norton

Is there any method of ear timing a 289? I've tried it by the book and still have a lot of pinging as well as the temp rising slightly above 180 if engine stays under load too long. Better gas (105 octane racing fuel)helps but there must be a better way. I also may be getting too much advance. Is there a perfect amount of advance I can set it to? I think mine is at around 32 deg. total advance right now. I also thought I may be a little lean. The carb is the original 3507s. Is there a jet size other than the original that I should try and where can I find them? I've never set the valve lash and would rather not, but will if there is a chance that could be causing this problem. Would that be a good idea?
Charley

63 R2 Avanti

It sticks in my mind that an R-2 is set at 24 degrees advance at 1600 rpm (with the vacuum advance disconnected and the line plugged). I drove my '64 R-2 6,000 miles in our Potomac Chapter Route 66 trip in 2003 and I bought nothing but 87 octance- no pinging problems. The engine was bored .060 over with hypereutetic cupped pistons so my compression may have been slightly lower than stock.
I don't trust my ear- I always use a timing light and external tachometer.

[img=right]http://www.frontiernet.net/~thejohnsons/64%20Daytona%20Convertible/Copy%20of%20DaytonaConvert7-20-06.JPG[/img=right]

Paul Johnson
'53 Commander Starliner (since 1966)
'64 Daytona Wagonaire (original owner)
'64 Daytona Convertible (2006)
Museum R-4 engine

Laemmle
08-02-2006, 08:09 PM
Good thing you do not have an R-1...todays pump gas will ping like a------------!:(:(:(:( I had Thibeault rebuild my dist....BETTER than new!!:):):)

I have given up attempting to run the Avanti on pump gas.....[8][8]as it is a summer use only,[8D][8D] I swallow hard and utilize Sunoco 110 RM/2 fuel..never pings...ever.....cost of driving bliss?.....eight bucks a gallon..[:0][:0][:0]

charley norton
08-02-2006, 08:16 PM
Thanks for the imput. I did get new weights from Thibeault and modified the advance shims to get the 30 degrees advance I now have. When I put the light on 24 degrees, the engine would barely run, so I ended up just turning it back until it sounded better and thats where I left it about a year ago. Well, actually, I remember after that it still ran like crap so I removed the shield and loosened the Dist. enough where it would turn with effort and took a drive . I did the go-stop-adjust-go-stop-adjust thing several times until it was as good as it would get. I'm thinking I could shim the advance and lower the total advance timing to closer to 23-27 degrees overall. But it still should of been better when I freehanded it. The secondaries have never worked right. If your barely into them, their OK, but if your floor it, it bogs out. Theres no black smoke like its burning rich or flooding out, so it makes me think its going lean. That may cause the pinging.
One thing I noticed is that when the engine is cold, and for the first minute to five minutes, it hardly pings at all. Thats why I thought valves adjustment could be the prob. It starts great and doesn't diesel after it is shut down. But the longer I drive it, the less amount of throttle it takes for it to start to ping. It has been this way almost as long as I have owned it so I have never enjoyed driving it. All you guys are up north and there is noone around here that knows any more than I do that could work on it. I think I would probably keep the da__ thing if I could ever get that fixed. I'm sure its a small stupid thing that I probably did to make it this way

63 R2 Avanti

sbca96
08-02-2006, 08:18 PM
Yah .. my R1 requires premium gas, and it will still ping. Luckily
it runs at a consistent 140 degrees (I have no idea why), so it tends
to be "ok" with the current crappy premium fuel.:D

I second the cold adjustment on valves, but keep in mind that a little
too loose is MUCH better then a little to tight!![B)]

Tom

GTtim
08-02-2006, 10:46 PM
Charley,
Since I've just installed an R2 in my Hawk this winter, I've come to realize that there is a lot to learn about tuning these beasts. Mine has a stock carb with stock jets and seems to do pretty well that way. I thought about trying to change it to a leaner mix, but decided to wait until later for that. I think the timing is a huge issue. Mine is set at 32 or 33 total advance and it doesn't ping on the premium 91 octaine or whatever it is. Peter Sant runs his at 26 and Ted Harbit runs his at 34. When I advanced it one more degree about two weeks ago the change in the idle was significant. I had no idea one degree would make that much difference. Has your distributor been gone through? Have you checked the centrifugal advance with the timing light? I know it sounds boring and way too technical, but like you say there isn't anyone else who knows how to work with these engines so you'd better get out the manual and wrenches. Anyway, you already know more about this engine than anyone else, so you can probably figure out what is wrong.
I also recomend that you check for vacuum leaks. Disconnect the vacuum lines and plug the hole in the manifold and see if it makes a difference, you could have a bad brake booster or a leak in a hose. Check it with a vacuum gage. Check the torque on the intake manifold bolts and the carburetor base. The metering rods in mine are 75/47 in .101 jets if that helps you any.
Maybe your problem is caused by carbon build up. One thing to try is warm up the engine and drive the car on the highway. Get it back to the garage with as little idling as possible and take out all the spark plugs. Number them by the cylinder they came from and line them up and look at the electrode ends. Are they all the same color? Black indicates too rich, white indicates too lean. I think tan to silver grey are the good colors, other people may know more about that than I do. If half of the plugs are a different color than the other half, you have a carburetor problem.
I hope this helps, come back and I'll try to help you more.


Tim K.
'64 R2 GT Hawk

charley norton
08-02-2006, 11:24 PM
I went through the distributor myself, but must of done well as everything came out right when the light was put on it.But it actually ran better before I built it. The weights were frozen shut before and the vacuum line was cracked and leaking so I know the advance wasn't working right. I don't think I have a vacuum problem as the advance worked right when I put the light on it
It's been a while, but I think I remember the centrifugal being around 14 or 15 degress and the vacuum being around 16 or 17 giving me the 31 or 32 total advance. I would like to say the timing marks are off because the chain is stretched but there is no chain. I did change to the petronixs setup because I hate points. When doing that, I had to buy a different set of wires.
I think I wrote down somewhere the markings on the metering rods but I'd have to find it to see if it cooresponds to what you have. I do remember bending one of the metering rods on my first attemtped to install it, but I straightened it out and it moved in and out just fine. I've checked it a couple of times since and it seemed to work good. It is in the interior shop getting carpet put in it now, but I may go get it tomorrow as the guy working on it got sick and is in the hospitol. If so, I'll plan to go ahead and do the valves and take the top off the carb(hopefully salvaging the gasket) and checking the condition of the floats,rods and jets.
As This is a problem I've had for a wyhile, I feel negitive that any of that will work. I think the car just doesn't like me.
Charley

63 R2 Avanti

Dick Steinkamp
08-03-2006, 12:22 AM
quote:Originally posted by charley norton
It's been a while, but I think I remember the centrifugal being around 14 or 15 degress and the vacuum being around 16 or 17 giving me the 31 or 32 total advance.


TOTAL advance = initial advance + centrifugal advance...vacuum advance is not part of the total advance equation (primarely since there is essentially no vacuum advance at full throttle).

I just set the advance curve on the 327 in my Starliner. Chevy's are a little more "advance happy" than Studes, so adjust accordingly. I have 26 degrees of centrifugal advance (all in by 3,000 RPM) and 12 degrees of initial advance. 38 degrees TOTAL advance. No ping with my 9.3/1 or so compression motor on pump 94 octane. The vacuum advance adds another 12 degrees...but ONLY at trailing throttle or part throttle. This would be a TOTAL of 50 degrees at part throttle over 3000 RPM (70 MPH cruise for me).

Here's a pretty good explanation (It's Chevy stuff so some adjustments are necessary)...

http://www.chevelles.com/forums/showthread.php?t=80222

My windy point being...your R2 should hold AT LEAST 32 degrees of total advance (centrifigual plus initial) and not ping IF carb mixture and other variables are correct, and if the distributor and vacuum advance are in good working order.




http://thenobot.org/images/s2d/s2d_01.jpg

charley norton
08-03-2006, 06:52 AM
You lost me,there. So you have three different components causing advance? Whats the initial timing? Thanks for the imput.
charley

63 R2 Avanti

KOOL R2
08-03-2006, 08:36 AM
Charley,

Remove the vacuum hose from the distribuor.Plug the line. Time the engine to show full advance of 24-26 degrees at 1600rpm. Reinstall the vacuum line to the distributor and you are good to go.

nels
08-03-2006, 08:56 AM
Most all I've read here so far looks like worthy stuff to look at. What I did pick up on is you did say the problem gets worse the longer the car is driven or the hotter the engine. When the engine is cold either the choke isn't open so the secondaries won't open. This would leads to the carb. Or the intake hasn't heated the carb enough to create the problem. If it was me, I would first look at the heat riser that was mentioned earlier and make sure it is open and not passing the bulk of the passenger side exhaust through the intake. The Avanti intake gaskets (the originals) had a restriction on the passenger side to inhibit exhaust from taking this route. Your's probably no longer has the correct gasket. The carb to intake gasket on the Avantis was also thick in an effort to reduce heat transfer to the carb. A return fuel line was introduced to keep the incoming fuel cool.Tim just mentioned vacuun leaks and after tightening the intake as Tim mentioned the primary leak would then go to the brake booster. You could check that by pinching the vacuum hose with a vise grip and see if the idle is affected. If the idle drops down then the booster has a leak and you are sucking air through it.
On the dist, did you check the shaft end play? Excessive end play can result in floating timing advance. Also some say correct heat range of the plugs can have some effect also.

Dick Steinkamp
08-03-2006, 10:23 AM
quote:Originally posted by charley norton

You lost me,there. So you have three different components causing advance? Whats the initial timing? Thanks for the imput.


Yep...three components...initial (or static), centrifugal, and vacuum. Initial advance is how most cars are timed. It's the number of degrees before top dead center that the plug fires with NO centrifugal or vacuum advance.

As Paul and Peter have pointed out, Avantis are "timed" at 1600 RPM which means a portion of the centrifugal advance is "in" when you time the engine...unlike most cars that are "timed" at idle with no centrifugal advance in.

Because of this, it is important that the distributor and centrifugal advance mechanism is in top notch working order. If the actual timing curve that your distributor is producing is different than the designed timing curve, it will be impossible to properly time the engine.


http://thenobot.org/images/s2d/s2d_01.jpg

N8N
08-03-2006, 01:12 PM
I agree with Nels, ASSuming that the distributor is OK, is there possibly a problem in the secondary circuit of the carb? Running lean will definitely cause some serious ping. Might be something as simple as a piece of debris in one of the fuel passages. Check all the other heat-related stuff as well, while you're looking at it.

Mr. Gasket sells a stack of alternating thin gaskets and aluminum sheet that is supposed to reduce heat transfer to the carb; it looks like a suitable replacement for the factory insulating gasket and might work a little better.

good luck,

nate

--
55 Commander Starlight
http://home.comcast.net/~njnagel

charley norton
08-03-2006, 10:31 PM
I've got to get my car back so I can check all this stuff. I will definately let ya'll know what I find and thanks for the help
Charley

63 R2 Avanti

bams50
08-04-2006, 12:01 AM
Tim's idea reminded me of my racing days...

The most successful team I ever drove for had a genius engine guy... one of his tricks was to have me go out for a race, run it as hard as possible, then as I came under the checkered flag I'd shove in the clutch and hit the kill switch; and have a tow truck push it in. He said that was the only way to get a truly accurate read on the plugs... He also ALWAYS put in a brand new set EVERY week- gapped by him ONLY- just before the Feature (Main) event...seemed like overkill at first, but his motors were always head and shoulders above all the rest... we won a TON of races...[:p]

Moral of the story is: Plugs are like reading a book if you know how to use them...

Robert K. Andrews Owner- IoMT (Island of Misfit Toys!)
Parish, central NY 13131
http://www.cardomain.com/ride/2358680/1

bige
08-04-2006, 12:08 AM
The ping will appear naturally when the engine is hot. The heat of the chamber is allowing the ignition to occur a little quicker under compression, 32 degrees might just be too much for your R2. My car runs better at the factory suggested setting than anything higher.

As a sidebar but related, blocking the crossover in the intake is probably the best mod I've made to the engine to improve performance and driveability. I had the car out Tueday and here in Jersey it's been very hot and humid. The car continued to idle well and drive crisply. It didn't behave that well before the block off.

Keeping the fuel charge cool will help reduce pinging. I have a 69 GP with a 10.5:1 motor and I know when the cold air intake hose has worked it's way loose. Detonation will occur at cruise rather than the top of the RPM range. Nothing will keep it from pinging in the hot weather, in the spring of the fall it's fine.

Ernie R2 R5388



R2 R5388

blackhawk
08-06-2006, 04:24 AM
quote:Despite what some will say, it's near impossible to get a good adjustment with the engine running.Mike - I adjust the valves cold because it is convenient, not because it is better. I think adjusting them with the engine running is more accurate IF you are using a valve gapper and not a feeler gauge. Here's why: unless the rocker arms are new, the valve stem will have worn a recess in the arm where the two meet. This makes it hard to get an accurate reading with a feeler gauge. When I was a kid helping my Dad rebuild engines, one of my jobs was to dress up the end of the rocker arm that comes in contact with the valve stem. Dad had a valve gapper (somewhat like this one that I found by searching the web... http://www.precisionmeasure.com/valve4.htm). It fit over the top of the valve stem where it meets the rocker arm. It had a gauge on top like a dial indicator that gave the valve lash reading. He had cut the top out of a valve cover to keep the oil from running down the engine while it was running. With this setup, there was no mess and adjusting the valves was fairly easy. He also claimed it was more accurate than settng them cold with a feeler gauge. Having done both, I tend to agree with him.
Dale

PackardV8
08-06-2006, 04:27 PM
FWIW, back in the bad old days, I used to be a believer in getting the valve clearances perfect. I even made my own version of the P&G Valve Gapper, using a special track to mount a dial indicator on the bottom valve cover rail of the Stude head. Then, last year, I had a convesation with Ed Iskenderian which put things into perspective.

Seems forty years or so ago, the P&G guys were very proud of their new invention and claimed increases on the order of forty horsepower. One day, they brought it around to Ed to get him to put it into his catalogue. Having run the lash a few thousand times himself, Ed was wasn't convinced. He suggested a test and let them use their dial indicator tool to set the lash to perfection on one of his cams in a SBC and had a dyno test run. He then had his dyno operator, the great Bones Balogh, take a couple of feeler gauges and randomly add about.004" to half the valves and set the other half to about .004" tighter, and run the engine again. The two horspower readings were essentially identical within the limits of the dyno repeatability.

The P&G guys went away mad and eventually faded from hot rod history. On an iron head and block Studebaker V8, cold and close enough is all we need.

thnx, jv.

PackardV8