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Hesitation at low speed, tming problem

gtcs1

Well-known member
Joined
Jun 17, 2006
Messages
350
Hi,

After a lot of work to try to improve the engine firing, apecially at low speed, I'm desperate to find a solution, my results so far are not as I expected.

I have installed my rebuild carb,(concours by Pony Carb). Since there was still hesitation, I did change plugs, plug cables, distributor cap, points and rotor. I still have hesitation specially at low speed upon acceleration.

My points were adjusted spot on at .021" per spec. I check the Dwell, it is at 24deg. The spec says between 24 to 29 deg.

Increasing the dwell angle towards the 29 deg, could it help? If yes, to do so, do I have to increase or decrease the point gap.

Any other thoughts to have a smooth running engine? I may have to end up going to a tuning place. Too bad, I feel I'm not far from fixing it....

Thanks
 

Mosesatm

Well-known member
Joined
Jan 18, 2005
Messages
9,010
The dwell should be more towards the middle of the scale or even closer to the upper end. To increase the dwell decrease the point gap. You may want to consider a Pertronix system and throw the points away. I am very happy with mine.

Here are a few questions that may help pinpoint the problem.

- What is your idle speed?

- Is the AC activated when it hesitates?

- What is your initial timing set at? You may want to kick it up to 12 degrees from the factory recommended 6 degrees.

- Do you have a single port or double port vacuum advance? If it is a double there should be little or no vacuum going to the front port at idle. Same is true for a single-port setup - little or no vacuum until you hit the gas.

- Is the distributor in good working order? If it is worn it can be messing with your timing.

- Is the vacuum advance working?

- Does the car idle well?

- Is it possible to adjust your carb's air/fuel mixture or must you replace the jets?

- Have you adjusted your carb's idle screws?

- The accelerator pump should be OK since it's a freshly rebuilt carb but it may be torn.

- What is your spark plug gap and how do the plugs look? Are they wet? Do they all look the same or is one a little different?

- Can you hear a vacuum leak anywhere? Listen inside the car also.

OK, I'm done, now the real mechanics can take over!
 
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franklinair

Well-known member
Joined
Mar 1, 2007
Messages
4,740
Did it have a low RPM hesitation before? If not, what have you changed?
Did it stumble before carb o'haul? (possibly carb accel pump)

For point dwell, I always set it in the middle of the hi-lo specs.

Dual vacuum distribitor? Be sure vacuum lines are correct.

Timing = 8 deg BTDC (and she'll be happy)

Idle RPM (A/C off) 600 - 650 (and she'll be happy)

Pertronics was a Great recommendation.
Neil Hoppe
 
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PNewitt

Guest
Arlie covered so much, I doubt I'd have anything else to add, but even if you have a great carb, you may have a problem with the carb gasket, and/or the top of the intake is uneven, letting air inside through the underside of the carb (or top of the manifold).

I've had all kinds of carb-to-manifold air leaks over the years. I've seen guys stack about four gaskets in a desperate attempt to stop air from getting in from the bottom side of the carb.

Do you have all the vacuum lines hooked up? Is the rubber of the lines OK, and how they attach to the metal hookup tubes?

There is also the possibility that the carb base was bent slightly while being bolted down--and/or it was torqued too tight, and that is causing air from getting in from the side, too. I once had bent carb bolts in the (Cobra) intake, and it did that to the carb.

What sounds like the problem is that your air/fuel mixture is too lean when you start to accellerate. A vacuum problem, or something leaning out the gas flow is causing the problem. Try a vacuum gauge on the main line at the firewall, or off the vacuum hookup at the rear of the carb (??), and see if the problem is at the base of the carb, OR one of the vacuum lines is bad.

Definately check the vacuum line from the engine or carb and the distributor.

And-- the intake to head gaskets can let air in, also. But that is a longshot possibility for now.

And! If the points are not opening up at all at low RPM, you can have a problem, too. You can get the points set, then lose the gap while tightening the little screw to set them by overtorqing it. There is a fine art to getting that right. I like the Pertronix version--and I think that Crane has a version of that,now, too.

Good Luck. We, all at some time have to get over this same hurdle--it's a "Mustang right of passage"... It's like owning an old plane, you have to smack it, and say: c'mon, ol Betsy"...

Keep us posted in how it goes.

Paul N.
 

franklinair

Well-known member
Joined
Mar 1, 2007
Messages
4,740
These are all good pointers & suggestions - but - the question to be first answered is: did the problem previously exist?

If it did previously exist, there are many possibilities- most of which were mentioned above.

If it did NOT previously exist, what was changed between then & now?
You mentioned the O'hauled carb. Is this the only change? If so, That's where I would first check.
Were the vacuum lines removed/disconnected? Double check connections.
You mentioned the point setting. You're within tolerence @ 21 deg dwell.
My first suspicion would be a vacuum problem, not a wide open leak, or the idle would be very rough also, and you didn't mention rough idle.
Hope this helps.
Neil Hoppe
 

Mustanglvr

Well-known member
Joined
Dec 4, 2004
Messages
3,258
My car did the same thing and we finally figured out it needed a new vacuum advance.
 
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gtcs1

Well-known member
Joined
Jun 17, 2006
Messages
350
These are all good pointers & suggestions - but - the question to be first answered is: did the problem previously exist?

If it did previously exist, there are many possibilities- most of which were mentioned above.

If it did NOT previously exist, what was changed between then & now?
You mentioned the O'hauled carb. Is this the only change? If so, That's where I would first check.
Were the vacuum lines removed/disconnected? Double check connections.
You mentioned the point setting. You're within tolerence @ 21 deg dwell.
My first suspicion would be a vacuum problem, not a wide open leak, or the idle would be very rough also, and you didn't mention rough idle.
Hope this helps.
Neil Hoppe


Thanks guys,

I feel I'm getting there with your help.

There was a bit of hesitation before but as far as I can remember it was kind of general, and I thought it was linked with the gummed carb.

So I got it rebuilt by Pony Carb.

After reinstalling, I thought it was hesitating a bit, so I decided to replace plugs, plug cables. That improved only slightly. So I replaced the point, cap, rotor and condensor.

You may be right with the vaccum leak, since I kind of hear something sporadic. At fast idle, I don't feel it too much, which would make sense since then there is plenty of vacuum, so a leak would have minimal impact.

At idle (slow), I feel the sporadic miss, and kind of hear that hiss then. It's not rough, It's much more a miss, and my vacuum gauges and Tach gauge show this drop then. So I'll hunt that leak.

It is quite possible that upon disconnecting all lines for the carb overhaul, old lines may have been damaged, Also the carb base may have a leak at the gasket area. I'll check also the PCV hose and valve itself. Any other area?

I read stuff about burnt valves etc, but I doubt it. The exhaust is clean, no dark smoke or soiled tail pipe.

So I'll try to see if there is a leak. I'll look for noise, and I'll use carb cleaner in spray to isolate it. If that could be just that......

Thanks again for helping.
 
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P

PNewitt

Guest
I was going to suggest the use of carb cleaner--but I didn't want to promote something potentially dangerous like that on the 'net.

That stuff is really flammable (WD-40 is REALLY flammable); but if you are careful, and knowledgeable, it can work for you to find an air leak, especially at the carb gasket. The idle will increase if the carb cleaner goes throug han air leak, telling you that it's there.

It sounds like you've almost found it. We're here to help.
Your problem--and it's solution will help others that read about it.

Keep us posted.

Paul N.
 

robert campbell

Well-known member
Joined
Apr 10, 2007
Messages
4,321
Your vacuum gauge and tach will fluctuate when the car misses. It may not be a vacuum leak that causes the miss, but the miss that gives you the low vacuum.

Please give us these specifics.
1. What vacuum does the engine run at hot idle in park or neutral?
2. What is your initial timing set at?
3. Do you have a single or dual diaphragm vacuum advance distributor?
4. What type of carburetor? Autolite, Holley, 2 or 4 barrel?
5. What RPM are you idling at in neutral/Park hot?
6. Do you have the idle stop screw completely backed off, and the idle is still fast?
7. Did you set the idle screws after installing it? Most Holleys and Autolites are in the 1 to 1 and ½ turn out range.

After we discuss the above we will go from there. Have you done a recent compression test?

Rob
 
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gtcs1

Well-known member
Joined
Jun 17, 2006
Messages
350
Your vacuum gauge and tach will fluctuate when the car misses. It may not be a vacuum leak that causes the miss, but the miss that gives you the low vacuum.

Please give us these specifics.
1. What vacuum does the engine run at hot idle in park or neutral?
2. What is your initial timing set at?
3. Do you have a single or dual diaphragm vacuum advance distributor?
4. What type of carburetor? Autolite, Holley, 2 or 4 barrel?
5. What RPM are you idling at in neutral/Park hot?
6. Do you have the idle stop screw completely backed off, and the idle is still fast?
7. Did you set the idle screws after installing it? Most Holleys and Autolites are in the 1 to 1 and ½ turn out range.

After we discuss the above we will go from there. Have you done a recent compression test?

Rob

Hi Rob,

My carb is the original Autolite 2100 2V, just been rebuilt by PonyCarb. I didn't start to play with the mixture and idle screws yet, I want to isolate the problem first if possible.

Ponycarb preadjust these screws on a test engine, so I should only do fine adjustment of them. Hence it should not (I hope) have too much relation or impact on my problem.

As far as the values (vacuum, low and fast idle speed), I'll play with the car tomorrow, looking first if there is a leak first,so I should record the values as I work on it, I'll let you know.

gtcs1
 

robert campbell

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Joined
Apr 10, 2007
Messages
4,321
Even though Pony carbs set it up on a test mule, it needs screw adjustment immediately. Float level and many settings must be maintained on all engines, but the idle mixture screw is the adjustment that allows a carb to work from engine to engine. Every engine needs its own special adjustment. You should do this before you go much farther, unless it runs so bad you know it has a huge vacuum leak.

First get you screwdriver and spin the screws in slowly and count each turn to the nearest 1/4 of a turn. Tighten very gently against the seat to stop. Find out how many turns out they are. You will not hurt a thing.

Once reset, start the engine and drive it to get it fully at op temperature. Now with it idling in park, adjust the linkage/throttle stop screw to a 500 to 600 RPM if the engine will hold it. I assume you have a basically stock engine. If it will not idle at 500 or 600 get it as slow as possible. Now go to the air screws. Seat of the pants listening works very well. Turn one out 1/2 a turn. Does it run faster? If it does leave it. Try the other screw. Turn it out 1/2 turn. If it runs even faster, great. Your goal is to get the fastest smoothest idle in this manner. But between each try you need to adjust the throttle/linkage screw out to slow it down to around 600. If the throttle plates are open too much, the idle screws are not positioned correctly on the transfer slot in the throttle plate. So you are wasting your time. That is why the engine must be fully warmed up with the choke fully open. They may need to go in vice out. If your first try out makes it run like crap, go back to the original and try a 1/2 turn in. You will find a point that either a half turn in or out seems to make no difference in RPM. Split it and call it good. Also, one screw may be set a bit more in or out than the other. This is normal.

Do not be afraid of your idle mixture screws! The only harm you can do is to tighten them to tight and ruin the seats or not have any idea how many turns they are out when close. You may solve a bunch of your problems with a simple turn or two.

Tell me about the low speed hesitation. That may be another story.

Rob
 
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gtcs1

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Joined
Jun 17, 2006
Messages
350
Hi Rob,

Thanks for these tips.

I tried to find a leak, didn't found it. I`ll try what you say. Nothing to loose, worst would be no change, and I'll have seen the effect of mixture screws adjustments. As long as I remember the original position of the screws, I can always put them back there.

So far, here is what it feels; At fast idle, RPM looks good and stable upon starting the engine.

After warming up, back to regular idle, there is miss, and when I drive it, on slow accelration, from halt, it hesitates few times until I get a certain speed, I guess this is linked to the miss I felt in park.

Story to follow. Nevertheless, quite interesting for me.

Thanks all.
 
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robert campbell

Well-known member
Joined
Apr 10, 2007
Messages
4,321
Hesitation at low speed. Another story. First of all if the idle circuit is not correctly adjusted it will affect the transition from idling to moving forward. A 60’s carb has four circuits. The choke circuit, idle circuit, the transition circuit and the high-speed circuit. An improper float level can affect all three circuits. The choke circuit is kinda self-explanatory and it can be set completely off and not affect warm engine operation. It is the compensation circuit between cold to hot. Many times you can adjust a carb to work on all the “warm” operation circuits and do the choke last. Many times that is what I do. The throttle stop screw and the air adjustment screws mainly control the idle circuit. If you have an engine in good condition with not air leaks, you should be able to set the carb to allow the engine to run smooth at 600 to 700 RPM. Assuming a stock camshaft and engine. Air leaks, warped metering blocks, dead cylinders, and ignition problems can cause missing and uneven idle. Assuming you can adjust the idle screws to get you smooth then we go from there. Common mistake is to have the idle stop screw opening the butterflies to far making the idle screws ineffective. Set that throttle stop screw way down when you adjust the airscrews. 4 barrels have another variation as the secondary butterflies can be opened to far making adjust the primary throttle stop screw way too far. Now the butterflies on the primary are to far-closed in relation to the transition slot in the base plate. I have worked on many a 4 barrel that needs the secondary stop screw closed a turn or two.

The transition circuit is the power valve and the acceleration pump. If you have a nice smooth slow idle when warm but experience hesitation coming off the stop light you have some transition circuit problems. A Holley has infinite adjustments for the accelerator pump in the form of cams, high volume pumps, and linkage adjustments via a screw and spring. Autolites have a series of positions that the accelerator pump linkage can attach to speed up the pump or slow it down. A stock motor should use the stock setting. Again, if the idle circuit is incorrectly adjusted it will affect the transition circuit. The power valve in a carb is important that it is not damaged. If it is the car will run excessively rich. A backfire up through the carb will damage a power valve in a stock autolite or an old holley. Normally a blown power valve will not harm performance much but gas mileage will drop a bunch. Just one stack up through the carb on a cold engine will do this.

The high-speed circuit is the emulsion tubes in concert with the main jets. If the float level is correct and the motor stock the engine should run fine at high speed. Normally not much to do to this in a stock motor. Lots of fun here in a high performance.

Hesitation at low speed transition. First be sure the idle circuit and float level is correct. If it is, sometimes a small adjustment to the accelerator pump linkage will help. If the power valve is blown that needs to be addressed first. It riches up the whole carb. All of this assumes the correct timing; no air leaks, no dead cylinders, no bad vacuum advance, and correct hookup of the vacuum advance.

Choke circuit another story in itself. Once it runs good we will adjust that in.

Rob
 
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gtcs1

Well-known member
Joined
Jun 17, 2006
Messages
350
Even though Pony carbs set it up on a test mule, it needs screw adjustment immediately. Float level and many settings must be maintained on all engines, but the idle mixture screw is the adjustment that allows a carb to work from engine to engine. Every engine needs its own special adjustment. You should do this before you go much farther, unless it runs so bad you know it has a huge vacuum leak.

First get you screwdriver and spin the screws in slowly and count each turn to the nearest 1/4 of a turn. Tighten very gently against the seat to stop. Find out how many turns out they are. You will not hurt a thing.

Once reset, start the engine and drive it to get it fully at op temperature. Now with it idling in park, adjust the linkage/throttle stop screw to a 500 to 600 RPM if the engine will hold it. I assume you have a basically stock engine. If it will not idle at 500 or 600 get it as slow as possible. Now go to the air screws. Seat of the pants listening works very well. Turn one out 1/2 a turn. Does it run faster? If it does leave it. Try the other screw. Turn it out 1/2 turn. If it runs even faster, great. Your goal is to get the fastest smoothest idle in this manner. But between each try you need to adjust the throttle/linkage screw out to slow it down to around 600. If the throttle plates are open too much, the idle screws are not positioned correctly on the transfer slot in the throttle plate. So you are wasting your time. That is why the engine must be fully warmed up with the choke fully open. They may need to go in vice out. If your first try out makes it run like crap, go back to the original and try a 1/2 turn in. You will find a point that either a half turn in or out seems to make no difference in RPM. Split it and call it good. Also, one screw may be set a bit more in or out than the other. This is normal.

Do not be afraid of your idle mixture screws! The only harm you can do is to tighten them to tight and ruin the seats or not have any idea how many turns they are out when close. You may solve a bunch of your problems with a simple turn or two.

Tell me about the low speed hesitation. That may be another story.

Rob

Hi Rob,

I'm getting there. Big difference so far.

I was thinking that something was wrong with the timinig, that's why I wasn't playing with the fuel mixture screws. So I went ahead as you suggested with the 2 fuel mixture screws (2 barrels). What a difference.

I ended up unscrewing the left screw (pass side) 1.5 turn and right screw (driver side) .5 turn. It is pretty good with that. I rechecked the timing, the distributor location did not really need any change, it was good already.

So my recent figures are 575-600 RPM in Drive (auto trans), 25 deg dwell, dwell specs says 27 deg, I may try to enlarge it again.

The vacuum in Drive is 19 in.

A problem I see now, is when returning from higher RPM, the idle speed is a few 100 rpm higher. I tried to lower it with the idle speed screw, but I'm bottoming on the dashpost screw. So I realize when I push the throttle lever forward, this is compressing the dashpot a bit, so I get the 575 value in drive.

I need to learn about this dashpot feature and adjustment.

After all that, I still fell a little bit of hesitation at low speed during acceleration when I start from stop. If I leave fast, not as noticeable.

In any case much better than before, so the trouble wasn't timing but too lean a mixture.

I can feel more power now. But I would like to get ride completely of this hesiation, even though it is small. I'm getting picky. Any more advice? You hit it right on the head.

I'm left with the dashpot adjustment for my idle (may be), dwell angle 2 deg too low. I wonder if this can influence the slight hesitation at low speed. I may play again with the timing to get the optimal point, which would be about a 1/16 in. rotation CCW before the popint where you can just start to fell pinging at high speed.

Thank you so much Rob and the others for advices.
 
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PNewitt

Guest
As a side help, the "anti-stall dashpot" is actually a coil inside this round housing, with a pin that pushes against the throttle linkage (a pre-bent angled part of the throttle) when it's cold. It's purpose is to keep the idle rpms up when you first start it on a cold morning. As the engine gets warm enough, the coil inside the dashpot unwinds inside it's housing, and the pin goes back down to a "normal", non-use position.

So--it's something to adjust when it's cold.

It sounds like you're almost there!

Paul N.
 
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gtcs1

Well-known member
Joined
Jun 17, 2006
Messages
350
As a side help, the "anti-stall dashpot" is actually a coil inside this round housing, with a pin that pushes against the throttle linkage (a pre-bent angled part of the throttle) when it's cold. It's purpose is to keep the idle rpms up when you first start it on a cold morning. As the engine gets warm enough, the coil inside the dashpot unwinds inside it's housing, and the pin goes back down to a "normal", non-use position.

So--it's something to adjust when it's cold.

It sounds like you're almost there!

Paul N.

So if I understand right, when the engine is hot, like it was in my case, I should adjust it so it just doesn't touch the throttle lever adjusted for 550-600 RPM at idle in park. In my case it is touching the lever in a hot engine condition. I needed to push it about 1/16in to reduce the RPM at the 575 value.

It would make sense also since I was thinking the fast idle felt a bit high. So if I move the dashpot 1/16in, it will also affect the fastidle value for about the same RPM value, i.e. about a drop of 200 RPM.
 

franklinair

Well-known member
Joined
Mar 1, 2007
Messages
4,740
Uh-Uh.
What Paul described as the "anti-stall dashpot" (a coill spring inside a round housing), is the automatic choke. It is adjusted when the engine is cold, closing the choke butterfly (leaving acout 3/8" open). Then the cold idle screw is adjusted to set the cold idle RPM. (I usually set mine @700-750RPM).
As the engine reaches operating temp, the choke relaxes, letting the cam operated by the automatic choke move to a neautral position. Then set your idle RPM to the desired setting (I use 600 RPM) using the idle screw adjustment.
The Dashpot' s intention is to let the RPM go SLOWLY to the idle setting when the engine is warmed up. To adjust the Dashpot (engine warm & idling @ 600 RPM) loosen the nut that locks the Dashpot in position, and screw the Dashpot out (towards the idle linkage) which will start to depress the Dashpot plunger. The desired effect is to let the Dashpot plunger slowly let the linkage go to the idle position (600RPM)
After you have made these adjustments, and everything is warm and idling nicely - adjust the 2 airbleed screws (the ones you mentioned earlier). One at a time, turn the screw inward until the engine gets rough. Back the screw out 1/2 turn. Do the other screw the same way. Now the choke idle, warm idle, and air bleeders are all set. (If you had a vacuum gage hooked up to the manifold, you would notice that the idle vacuum is dead on).
Hope this helps.
Neil Hoppe
 

robert campbell

Well-known member
Joined
Apr 10, 2007
Messages
4,321
You are getting very close. Neil and Paul have good information on the dashpot. The function of the dashpot is to keep the engine from dying when the throttle is “slammed shut” so to speak. A quick stab and return to idle. Neil’s advice on adjustment is spot on. If you are not having problems with the engine dying when returned to idle, I would back it off completely until you get you idle screws and throttle stop screw adjusted the way you want.

The hesitation. You have great vacuum and I assume the engine idles smoothly. You should be very close on idle circuit adjustment. The dwell is a possibility, but I think timing will improve the situation. Do you have a single diaphragm or dual diaphragm vacuum advance? In any event, turning the distributor clockwise will advance the timing. Turning it counter clockwise will retard the timing. You do not discuss timing figures, so I assume that you may not have a timing light. Pinging is critical. Do not let an engine ping heavily under load or you can hurt it. Getting a timing light would be very beneficial. At the same time, it must be close. Put a mark or two down on the distributor where it enters the block and try turning clockwise a bit. The engine should increase in RPM slightly. If your timing was retarded a bit, you should go back over the idle screws again. They still should be very close. Try a test run and see what happens. A bit of advance should eliminate the low speed hesitation. Pony carbs are top notch and they should have the acceleration pump spot on. If we continue to struggle we may discuss a different hole on the acceleration pump linkage.

Try the timing advance first.

Rob
 
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gtcs1

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Jun 17, 2006
Messages
350
You are getting very close. Neil and Paul have good information on the dashpot. The function of the dashpot is to keep the engine from dying when the throttle is “slammed shut” so to speak. A quick stab and return to idle. Neil’s advice on adjustment is spot on. If you are not having problems with the engine dying when returned to idle, I would back it off completely until you get you idle screws and throttle stop screw adjusted the way you want.

The hesitation. You have great vacuum and I assume the engine idles smoothly. You should be very close on idle circuit adjustment. The dwell is a possibility, but I think timing will improve the situation. Do you have a single diaphragm or dual diaphragm vacuum advance? In any event, turning the distributor clockwise will advance the timing. Turning it counter clockwise will retard the timing. You do not discuss timing figures, so I assume that you may not have a timing light. Pinging is critical. Do not let an engine ping heavily under load or you can hurt it. Getting a timing light would be very beneficial. At the same time, it must be close. Put a mark or two down on the distributor where it enters the block and try turning clockwise a bit. The engine should increase in RPM slightly. If your timing was retarded a bit, you should go back over the idle screws again. They still should be very close. Try a test run and see what happens. A bit of advance should eliminate the low speed hesitation. Pony carbs are top notch and they should have the acceleration pump spot on. If we continue to struggle we may discuss a different hole on the acceleration pump linkage.

Try the timing advance first.

Rob

Hi,

Finally got the hesitation out tonight, runs like a charm.

Got help of a older mechanic, used to work on the engines.

Turned out that it was just the timing which was wrong. Used a timing light and it was close to 20deg adv vs 6deg per spec. After we readjust, that's it, it's perfect. I've been waiting for this for a year... Rob, you were right. I've just been mislead by Pony Carb instructions

Pony Carb recommend not to use a timing light, but instead just to rotate the distributor by hand, watch the RPM when it's at its peak, and stop it there. They say on an old car, you can't rely on the timing mark because the harmonic balancer, made of rubber, will be all desadjusted. My mechanic says it's kind of rub... So we used the proper tools., and I learned tonight the trick of timing, using the proper spec of my shop manual, with the proper tools. So Pony Carb did a great job as far as Carb rebuilt., and a poor one as far as set-up instructions.

Case closed. This engine runs so smooth now.
 

robert campbell

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Apr 10, 2007
Messages
4,321
Great news!!! Nothing ruins the fun of driving a car more than a large flat spot or a huge exhaust leak!!

I like to start my timing at the stock specs like you did. Can't imagine why Pony carbs would recommend an approach to timing like that. Now as you drive it test it on a bit of a hill under medium load. Lug it down good and try some medium to heavy pulls while you are at full temp on a hot day. Those days are gone for this year in the Northwest!!! If you do not experience any pinging, you might sneak the timing ahead a couple degrees. You want to get it where it pings lightly under this situation, but no heavy pinging. Heavy pinging ruins an engine very quickly! Of course you need to run the same octane gas all the time.

Ah octane ratings….. One of my favorite subjects. You car should run just fine on today’s gas. And don’t get me started on hardened exhaust seats…. Unless you got 400,000 miles on your car like Paul!!

Rob
 
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