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1275 valve adjustment

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Rut

Rut

Obi Wan
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I've adjusted the valve settings on the 1275 with Kent Road/Rally, 276 cam to .016" on both intake and exhaust, cold. The previous settings were all over the place and I feel better having researched and set them properly. I also performed a compression test and the results were:
1 185 and 190
2 186 and 190
3 189 and 195
4 184 and 184
This was with the throttle closed then open. No 4 was reluctant to post anything unless the throttle was open! The enging runs well, but the spark plugs were carbon fouled. From the looks of them I'm surprised it ran at all. They are NGK BP6E S plugs and I need suggestions for a good plug along with thoughts regarding the compression results. Getting closer everyday!
Thanks, Rut
 
If it don't SUCK it can't BLOW. Compression readings with closed blades? Not indicative.

I'd be looking for Champion plugs, as well.
 
I'm not sure I understand, but the car has a single Weber and the 'blades' are slightly open. Is that what you mean?
Thanks, Rut
 
What the DOC means, is wide open throttle.
It is like us, if we can't breathe in, we can't breathe out!
This is the only true way to get readings.

Dave :savewave:
 
I gotcha! The difference was listed above and I was surprised that no 4 had a tough time recording anything before I opened the throttle. The numbers I listed with a closed/slight open throttle is where the carb is set, the second number is when I pulled the cable and opened the throttle, maybe 1/2 to 2/3 open. Should I repeat the test with just a wide open throttle? It's been a long time since I've done this and I don't remember much about the 60s. Are these numbers good, ok, or bad?
Thanks, Rut
 
I think that the second readings are a good evaluation.
The numbers are consistent one to another and strong. I wouldn't worry about it too much.
I don't entirely remember the 60S either, musta been fun, EH!
If there is more help needed, just ask.

Dave, An Americanized Canuck!

:driving:

P.S. I agree with Doc on the Champion plugs
 
NGK BP6ES is a good plug for your level of tune on the engine. A Champion N9YC is the equivalent. BP7ES/N7YC is next colder. Likewise BP5ES/N11YC is next hotter.

With the valves adjusted, put in a new set of plugs, take a drive and check coloring. Looking at the plugs after idling and shutdown is too misleading. Find a nice road and while running about 40-45, slow quickly, pull off the road to a spot to check the plugs. A nice light tannish color, without too much black oil speckling on the insulator is what to look for. The fuel burn will also discolor the plating on the body and it may be a yellowish-green look. Nothing to worry about. Silver beads on the ground electrode and the insulator is aluminum. Usually not a problem unless you are running way too much ignition advance.

HTH,
Mike Miller
 
Thank you for the info! The car's not on the road yet and it will be a little while before it is. I will get the plugs, cap, rotor, wires, etc. to freshen everything up before it hits the road. I'm running the Crane electronic ignition as well, do I need to gap the plugs more than the .025 standard?
Rut
 
I would start with the 0.025" clearance. Once you get the car tuned in with the carburetor, you can check the ignition performance. Look for the little "half-moon" electron discharge signature on the center electrode. If there isn't much of one, stay with the 0.025" clearance. If you have a nice big arc across 1/2 the electrode or so, then open the gap up a little. Probably not more than 0.030". On the Electromotive ignitions I run, I run 0.032" gap. A CD ignition can run more, but that is because of the amount of stored energy in the capacitor. If it is just electronic, then stay closer to the stock adjustment gap.

Mike Miller
 
The ignition is a Crane Cams Fireball XR700 and a Crane PS40 Street Coil...I'm assuming that's just an electrinic ignition?
Thanks, Rut
 
The XR700 Crane is a good unit (tho I'm Old School, prefer points). A gap of 0.028"~ 0.032" is going to be what the Champion will want in range.
 
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