I'd call those numbers typical of an engine somewhat worn but still in decent condition. Re the poor performance, check the spark timing carefully. These ol' critters are pretty sensitive to the spark advance setting. And don't use the book figure for the advance (i.e., none), as that's for 80 octane fuel. I'd set it at 5 degrees and go from there based on results.

BTW, the "standard" way to take compression readings is with the engine warm, all plugs removed and the throttle blocked full open

Cheers
I've tried all sorts of timing and see best results with it set on about the second long mark advanced which I believe is 5 or 6 degrees advance.
Knowing that the compression is acceptable I'll keep fiddling.
Next check is to see if dissy is a tooth out.
Thanks Simon

Simon,

Have you checked to see if your centrifugal advance is working properly? If the springs in it are weak, it won't advance the timing as much as it should. I had this happen. After I put in a distributor with good springs, my power improved significantly.

You could also see if your vacuum advance is working. It doesn't add any power, but it improves economy

Per

Good suggestion, Per. Years ago I was asked to look at a '37 Hudson 8 that didn't want to go more than 30 mph. Acted like there was a governor on it. Found the advance mechanism all rusted and not moving at all. Cleaned it all up and the car ran beautifully.

I respectfully disagree that the vacuum advance has no contribution to performance. The initial advance provided by that device, plus the significant degree generated by the mechanical advance yields something in the range of 30+ degrees of total advance.....not to mention the significant air leak from a ruptured vac adv. diaphragm (if it is).
Bottom line: Check all of those things. An engine running at an effective 30+degrees of retardation (at the crank) can cause bad downstream problems like poor performance, overheating, burned exhaust valves, cracked exhaust/intake manifolds......the list goes on.
"Just rebuilt" can be your first clue. Sellers like to say that.
F

I have to disagree about weak advance weight springs. If they are weak you will get much faster advance curve.

Geoff,

You're right. I didn't express myself clearly. The springs were permanently partly stretched. They did not pull the weights all the way in when the engine was turned off. Therefore, when the engine was turned on and speeded up, there was only about half the advancing motion left in the system.

I had first tried to correct the condition by advancing the timing. This improved the power, but the engine "fought" the starter, so I could not run it that way.

Per

Many thanks for the replies.
Mechanical advance was the first thing I checked. It's all free and does advance the timing (with vac advance blocked)
I have tracked down an original NOS
Vac advance canister which will be my next check. The current one is a modified chrysler one but is stamped 9 whereas the original is stamped 5.
The vac advance is working tbough but might be too "stiff"
I'm basing my torque expectations on the fact that people seem to rave about the hudsons torque but at the moment my old flogged out 1953 farm truck with a 216 ci straight six currently has way more power than the 262!
I'm taking it to my tune up guru mate tomorrow and will let you all know what we find.
Thanks again Simon

Frank, I'm curious about where you get the 30 degrees figure. My reference data for the '51 sixes says max mechanical advance is 9 degrees, vacuum advance adds only 4 degrees. Assuming a basic setting of, say, 5 degrees, that's a total of just 18 degrees. Other data sources might vary a little, but not enough to get anywhere near 30 degrees.

Park,
I must admit to squeezing off a couple of rounds from the hip and relying too heavily on my memory. I've spent more time lately on 212s than the later sixes and, so, had those numbers in my head.
Consulting the MPM, I see that the maximum mechanical advance for nearly all late sixes is 9 degrees and the vacuum advance provides 3.75 degrees. That, of course, yields 12.75 degrees if one disregards the initial setting but it's specified to be 0 anyway. Here's where I believe you've missed a detail: Those figures are distributor degrees, which is half of crankshaft rotation, so it's 25.5 degrees at a the crank which is where it matters. In my defense, I was thinking of the 212 figures which are the sum of vacuum advance (7.5 degrees) and mechanical advance (11.75 degrees) for a total of 19.25. This results in 38.5 degrees at the crankshaft, again, where it matters.
It's doubtful that very many of us ever reach the maximum since the mechanical figure is spec'd at 2000 distributor rpm......yikes! that's 4k at the crank. Sure.....they'll do it, but it's not cruising rpm.
I suspect that the reasoning behind expressing the spec in distributor rpm was to accommodate distributor test machines that were calibrated that way.
F

Frank, you got me on the distributor degrees. The brain is getting old. One comment on the "specified" advance as at TDC . . . in the spec's that timing setting comes with an important qualifier: "[i]Spark setting may be advanced [/i]during continuous high altitude operation or [i]with fuels of high octane of 80 or higher."[/i] Even our typical "regular" gas is significantly above 80. Running these cars at zero advance is throwing away fuel and power. Change the advance from TDC to, say, 5 crank degrees advanced, and you can readily tell the increased "pep level" by merely "blipping" the throttle. And the increase in gas mileage can be dramatic. With my Twin-H Hornet, when I increased the advance from the TDC setting the highway mileage went from about 14 to 18! That's significant.

Park,
Correct you are on the Octane subject. Like many people, I adjust the timing "by ear" (after initial setting) and the check to see what that result is. I've found that The Hornet and Jet like about 6 degrees while the '47 Six runs best at 8. I've advanced the latter to 10 without audible "ping" but it begins to have other symptoms when I go that far....like kick-back on hot restarts.
Frank

Park and Frank,

Your discussion got me to look into two manuals that contain information about timing advance.. I looked at information shown for l942 Hudson 6.

Motor's manual shows maximum centrifugal advance of 11 3/4 distributor degrees at 1570 distributor rpm.

Chilton's manual shows maximum centrifugal advance of 23.5 engine degrees at 3140 engine rpm.

Similarly for maximum vacuum advance, Motor's shows 7 1/2 distributor degrees
and Chilton's shows 15 engine degrees.

I have usually looked in the Motor's manual, but I didn't notice that the numbers were for distributor degrees,
so I have assumed that the centrifugal advance was at its maximum when I was driving at a comfortable
2000 rpm.

Thanks for clarifying this!

Per

Hi guys - I was reading this thread regarding compression testing and was somewhat envious of the quoted figures of 14 to 18 mpg. I decided to check the compression on my engine (308, single WGD carb) as a possible reason for typical fuel economy of 11 or so, even with a good 5-6 degrees BTDC in the base timing (87 octane fuel). Here are four sets of readings, cold vs. hot engine and dry vs. wet (2 squirts of oil in the spark plug hole:

Cold dry: 102, 102, 65, 90, 104, 103
Cold wet: 103, 109, 72, 100, 111, 110 - yikes, #3 sure looks low, doesn't it...but wait:!

Hot dry: 121, 118, 119, 118, 121, 120
Hot wet:: 126, 121, 126, 123, 132, 127

OK, so, has anyone ever seen a low cylinder come up to join the others when hot? Any guesses what to look for?

As for MPG - I'm wondering about the springs in my centrifugal advance. I'll take a look some day.

Thanks to all,

Mike