Thank you for the offer, that his the last thing any of us would want you to do in these times
So, I drove the car about 30 miles on Sunday. I have not done anything yet. It was running OK, not hesitating as much off the line, and while accelerating, actually felt strong. It was still pinging when i got on it a little.
I talked to another local engine guy(the one I did not use unfortunately). He was telling me how bad the pinging is and that besides the hesitation fix, I should look at getting different gears for my rear end (Currently 2.75 ratio) He said that would help a lot, he is also a big fan of the NO Vacuum and said if the distributor is set up correctly, it should run better that with the vacuum, something about lighter springs.
He also said I need to switch to NON ethanol premium gas.
I am going to try to go to Carlisle at the end of the month, not sure if I should try to get better gears and/or something else that might help the car.
Will not be taking the car.
Hi Mario,
In attempt to put things in the best order.
- Get the carb leaks fixed. Do a basic starting tune to the carb.
- Distributor fixed or replaced then turned. Driving around pinging can lead to engine damage. To quickly explain, as fuel burns in the cylinder, the flame travels giving a push on the piston. When you hear the ping, that is detonation. All the fuel charge is going off like a bomb causing shock to internal engine components and eventually something is going to give. Could be a broken ring, broken piston, etc.
I’m sure you are anxious to drive, but some tuning needs to happen first.
Though it’s not part of the problem, what is the gear ratio going to help? With a transmission that has a 1:1 high gear, you have to compromise between leverage and cruising rpms. What do YOU plan to do with the car?
Here is a good test to try before you change the gear ratio. When you get on the highway at cruising speed, shift from 4th to 3rd. See if the engine rpms bother you. Do you plan on racing the car? Is the majority of your driving in stop and go around town? Do you have plans of getting on the highway and want to keep up with traffic? If you want the best of both worlds, put in a bigger gear along with a 5 speed overdrive transmission. To do everything will be $4000+. So, careful consideration should be taken on whether you want to drive normal and cruise or make something that would be good for acceleration or if you want both.
Thank you,
I will start with the basic and check 1st on the carb, and then move on to the distributor and timing.
Currently it was running around 2500 at 65mph. I just want something I can drive around town, get on the highway and cruise,
I will keep you posted.
If someone is telling you that vacuum advance is not desirable then you need to find someone more knowledgeable to work on the car. 99% of the time you won’t be driving the car at wide open throttle. WOT is the only time you don’t need vacuum advance.
Mario,
If you can get the tuning somewhat straitened out, why not bring it to Carlisle?
Thank you Royce,
I echo that, I think you could get yours much closer with good tuning, but, in the end, vacuum advance is certainly a benefit for a street car.
I too would walk away from that shop, the springs in the distributor have nothing to do with vacuum advance on a Ford, one is optimized for one thing, the other for another. The only car I know of that purposely combines vacuum with the mechanical as a combined curve, is late 60s Pontiac, and the last GTO I did, we changed it to act like a Ford during a cam swap. The guy went from high test and pinging, to 89 octane and 2 more MPG.
The high octane for a stock rebuild is crazy, but when you advance the timing that much, I suppose that is what you need.
I will look for someone that can help me with this in Pittsburgh, start wit the carb and than the distributor, and once i get this, see if i need to change the gears
Thank you,
On Long Island I have no choice but to run ethonol, that all they have. Crazy. Anyway I started using some additive and a have a fuel shutoff in front of the carb and run it dry if it sitting for a while. I did disable my vaccine advance and used lighter spring to get it all in at the point I wanted but vacuumed or spring you need advance. If you are pinging bad check when you get your total all in. Maybe it’s too soon. Most vacuum advance units are adjustable with an Allen wench in the vacuumed port hole.
Ok so I front the back metering block were leaking, I ended up tightening the 4 bolts on the front and back of the carb, took the car for a ride and was still hesitating,
I checked the timing and he had it at 21 degrees. I backed it to 13, ran the car, no pinging, it is idling at 750, it seamed better
Mario brought the car out to Carlisle this past weekend. He brought a new Pertronix 3 distributor. We installed the distributor set the initial timing at 14, total topped out at 38 at 3500 rpm. Vacuum added another 20-21 degrees. The mechanical curve come in faster, all in by 3000 would probably be good. Vacuum might be too much. There wasn’t enough driving to really determine how much we’d need to knock it down. Tight mechanical springs causing a slow advance is probably what allows the vacuum to pull so much without being too much.
There is still an off idle bog----or low rpm loss. During a snap throttle in neutral the engine either dies or sputters then picks up. If you are above 1500 and snap the throttle it revs seamlessly. The accelerator pump shot appears to be quite sufficient. There was a very minor gap in the accel pump shot linkage, not enough to cause a problem. No change with the gap removed. Fuel floats are set at the correct level. This carb has a metering block with reverse idle mix screws. It actually ran best with them turned in to be seated. Could this carb work? Possibly, though I think there is a better carb available.
Here is some more about the bog. While cruising with the trans in a higher gear where the rpms are low enough—below 1500. If you give this throttle it bucks as if the ignition is being switched off-on-off-on. Once you get over 1500 or so it’s smooth. With the timing light flashing, with the pick-up on cyl #1, if I were to do a snap throttle, the light would stop blinking. I moved the light pick-up to the coil wire and I tried this several times without seeing a loss of light. Also, I tried this with the pickup closer to the cap on cyl #1 and again did not see a loss of light. Put it back near the plug on cyl #1 and you’d lose light during a snap throttle. It appears as if the spark energy is leaking. There are Delco spark plugs in the engine. I didn’t have time to pull one out. I wonder of the engine builder decided to put a big gap in them? Then with the increased cylinder pressure at low rpm would add résistance causing the spark to jump elsewhere. It would be nice to take a close look in the pitch black darkness for wire or plug leakage. Further inspecting plug gap or changing plugs would be a viable next step. Not sure what brand the wires are. If an Autolite script is not required I prefer a set of 8mm Taylor Spriro-Pro-----135* boots in black universal fit, Mario, if you are planning to buy. Universal fit means they will need to be terminated to proper length. Yes, it’s disheartening since you’ve already paid for this to be done. So, try plugs first.
I feel like this is more related to ignition as the loss is instantly on or off. Usually fuel will taper or fade to on or off. What got replaced is the whole distributor w/new cap and rotor and ignition coil. Problem still exists. The PROBLEM is less intense, not gone, but less intense when using a jumper lead from the battery to the coil B+, further leading me to believe this is an ignition problem. The coil is powered by the original resistor wire from the tach. If the problem were eliminated with the direct 12v I would feel better about saying the resistor wire is the problem. Mario had run a new strait 12v wire from the ignition switch to power the Pertronix unit. I was going to T power to the coil from this, but with 12v going to the coil, the tach reading was distorted and read about 1/2-3/4 of actual rpm measured on the timing light. I didn’t want to cause an unknown issue with the tach or underdash wiring. I would have liked to try a known good carb since there was nothing obviously wrong with it. What remains unchanged is the plugs, wires, carb.
For anyone wanting to upgrade their ignition, leave the Pertronix complete distributors for the GM guys. The unit consists of Delco copied components. The vacuum advance is NON-adjustable. Why would a performance distributor have a non-adjustable vacuum advance?!?!? The Delco style cap is too tall. After installing this distributor the Ford air cleaner rests on top of the distributor.
Glad to have met Mario this past weekend. I wish I could have made more headway on his engine problem.
What are you guys thoughts on this information?
Did this carb have sort of big plastic idle air screws?
Also the PIII is not compatible with our cars. It needs to be able to pull as much as 40 amps of current with the .3 ohm coil. That is just not going to happen unless you do a complete wiring harness with relay to supply power.
The low speed loss felt like a weak signal. It wouldn’t surprise me if the Pertronix 3 is lacking something to work properly.
No plastic idle screws. but there was a chrome sticker square shaped around the idle mix. With the screws closed it ran smooth. Open them to 1-1/2 and it was pretty rough.
I would also consider cross channeling in the carb. If the metering blocks were leaking, and he zonked it down, often the 4 corners of a Holley can “elf shoe”. Often is a bad word, almost always. If the guy who rebuilt it didn’t machine the throttle body metering surfaces, or at least carefully flatten with a long file, it could be not sealing and fighting transition fuel availability or booster fuel.
With two distributors doing the same thing, seems to me it would rule that out.
One option is to wait until the off season and send the carb to a reputable builder. One option is AED in Richmond, they can wet flow, or Joe Bunetic, St Louis I believe, or Drew Podjenic in GA who are sharp Holley guys
The distributor needs to be set up properly. You need something like 40 degrees total including vacuum, centrifugal and initial advance. I would try to achieve 10 degrees initial, 18 centrifugal, and the rest vacuum.
That is not going to change his problem. 28 degrees for total without vacuum is not enough.
The symptom this exhibits is like an on-off switch which feels like ignition. Not all ignition components were replaced. Or, as Bill mentioned it could be an insufficient power supply.
This engine is mild. He could put any brand of functional carb on there (maybe even the Chinese one) and drive smoothly. He ought to just put an Edelbrock carb on and not worry about wearing out hood hinges. The intended use of the car is cruising, so that extra few hp on top will never matter. Low rpm bucking and bog does matter.
While the carb might not be perfect, after experiencing the symptom, it just doesn’t feel like carb. Having the timing light stop blinking during snap throttle is showing that there is an ignition issue.