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By lovefordgalaxie - 9 Years Ago
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Hi guys,
I have something that is bugging me for some time now.
When I rebuilt my 292 back in 2010 I installed a Isky E-4 cam. The car runs great, and even tough at the time I installed the cam out of the box, without deepening the oil groove, the engine has great oil flow to both heads.
The thing that buggs me is the idle. The car never had the same idle it had when all stock. I was told the E-4 is not enough to alter the idle (not that I wouldn't install it because of that) but my engine doesn't idles as smooth as before. Along with the cam, the engine also has double valve springs, and 1,54 rockers. When all stock she had the lower ratio rockers.
Valve lash is correct, the carburetor is good (Autolite 4100), the car has no ignition problems, and drives super well, with no hesitations, flat spots, and has lot's of power. The problem is just the idle that is more vibrant than a stock engine.
My fear is having messed something out when rebuilding the engine.
For you guys with more experience on comparing cams, is the E-4 enough to change the idle?
Other than that, I've put more than 20 K miles on the 292, and it uses no oil, has more than 30 PSI of oil pressure idling at 750 RPM hot, and has a little more than 60 PSI on highway.
What do you think??
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By Cliff - 9 Years Ago
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Hi, I had that problem a long time ago and after a lot of work I changed the motor mounts (advise from an old man, now I am an old man) the rough idle went away (hard old mounts).
Cliff
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By Rono - 9 Years Ago
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I'm sure you will get a lot of responses from more knowledgeable people then me, but I am wondering why the double valve springs? I don't believe the E4 cam has that high of a lobe lift to require that. Did you have double valve springs installed before you rebuilt the motor?
regards,
Rono
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By charliemccraney - 9 Years Ago
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It is larger than most factory cams so it could have a little more rough idle. Shouldn't be too bad, though. What is the vacuum?
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By lovefordgalaxie - 9 Years Ago
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Thanks guys.
I didn't measure the vacuum on the intake, so I don't have that info.
On the vale springs, two of mine were shot, so I ordered a new set, and when it arrived it was the double springs. I installed it when rebuilt the engine. Figured it wouldn't be a bad thing to have since I use oil with high ZDDP. I wanted to go with a larger cam, but ended using the E-4. I didn't loose too much of the low end torque, as the car is very heavy (same body as a '66 Galaxie four door sedan), and my town has a lot of hills.
The idle is not exactly rough, it has more vibration than stock. The kind you can feel on the floor pans if you pay attention to it.
Both motor mounts, and the transmission mount were replaced with new parts back in 2010.
Friend of mine even put the guilt on my exhaust, that is dual with glasspacks.
The last mufflers I had when the engine was stock was a pair of Thrush Welded mufflers. I replaced them short after rebuilding the engine as they were too quiet...
This is how she idles:
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By NoShortcuts - 9 Years Ago
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Comments, Tulio.
1) Like Rono, I'm surprised that you're running dual valve springs unless you're counting a damper coil as an actual spring. No, a second spring would not be responsible for a change in the idle quality. It's an unrelated thought. I'm just thinking in terms of your usual rpm operating range for street and highway use and valve train wear and tear factors.
2) I'm with Charlie in trying to get a handle on your idle quality concern. What kind of a vacuum gauge reading are you getting at idle? In addition to the gauge reading number, is it a steady reading, or rapidly twitching (pulsing), or slowly fluctuating ('walking')?
GooD to hear from you. It's been awhile. Glad that you got that 4100 carb working okay! 
Regards,
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By lovefordgalaxie - 9 Years Ago
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Charley, great to hear from you too!!
Maybe I was mistaken, my "inner" spring is the flat kind. Not really a second spring. Around here they are called double springs, and the other triple.
I have to get a vacuum reader borrowed with someone. Then I can tell what it reads.
When I rebuilt the engine, all work was done by me and a friend that owns a shop, and we measured it. It was solid as a rock. But again it was back in 2010, and I don't recall the actual reading.
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By lovefordgalaxie - 9 Years Ago
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Here are the valve springs. Just pulled a valve cover and took a picture:
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By miker - 9 Years Ago
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Maybe a harmonic from the muffler change? I've had cars that needed resonators added, but at cruise, not idle. The comment about feeling it in the floor pan is what prompts this.
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By charliemccraney - 9 Years Ago
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That is a damper, not an inner spring. The vacuum gauge will tell you more.
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By lovefordgalaxie - 9 Years Ago
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Thanks Charlie.
After hearing from NoShortcuts Charlie I realized it's a damper.
Believe you or not, people here calls mine kind of springs a "dual". Not to be amazed, as people here call every single four barrel carburetor a "quadrijet" and a two barrel a "bijet"...
Well, will borrow a vacuum tester, and do some readings as soon as possible.
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By slumlord444 - 9 Years Ago
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It is not a stock cam. I will not idle like a stock cam. A vibration could be an exhaust system thing.
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By lovefordgalaxie - 9 Years Ago
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Well gentlemen, I took a reading on the vacuum.
Took the car to the local Ford dealer, where the chief mechanic is a close friend and used their vacuometer.
The engine was at operation temperature, idling at 750 RPM and the reading was between 13,5 and 14 inches (the scale is not that precise between a full inch reading and the needle oscillates about a millimeter, what I think is normal).
I was kind of expecting that, since all spark plugs read really good, the points are new, there is no excessive blow by, no popping on the carburetor, and the engine pulls really well.
The vibration is more of the harmonic kind, as it comes and goes in regular intervals. I'm starting to think it's the exhaust...
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By charliemccraney - 9 Years Ago
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That's probably about right. The E4 is pretty popular. Maybe someone who has one can confirm.
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By lovefordgalaxie - 9 Years Ago
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Well guys, I finally found the "source" of the problem.
Like I've told you guys, the engine mounts are new, so is the transmission mount.
Well, since apparently the engine itself checked out, and the Isky E-4 really provides a something rouger idle than stock, I started looking at other sources of vibration. The exhaust on the car is relatively new, and it's dual, with a H pipe. From the factory the Galaxie had only one exhaust pipe, and there was the problem. On the right side of the car, the side still with the factory rubber mounts, one of them was so hard that almost felt like plastic. Replaced that one, and the one near the tail pipe exit and the vibration on the floor pans disappeared like magic.
That made me worried about the 41 years old body mounts...
The car is not showing signs of having bad body mounts, and from the underside they do look good. Just as a precaution I started looking for a set of body mounts, and NOBODY reproduces those for a '66 Galaxie, that is what my '74 is.
If someone would, they would have a huge market here in Brazil, as all our Galaxies are versions of the 1966 model.
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