1957 Stock 36hp Dwell Angle Measurement

[mark1laura]

I have a stock 36hp engine (rebuilt) with a Bosch VJU4BR8mk distributor (disassembled and cleaned/low miles as far as I know). I have read through the forums and most mention dwell angles in the mid 40's. The Bentley manual (pg E 5-16) states the dwell for the BR8 should be 52 to 56 degrees. When I set the point gap to .016" I get a dwell angle around 44 degrees (points only have a few miles on them). I would prefer to set the points according to the dwell angle but to get to 52-56 degrees that is going to be a pretty tight point gap. Would like to sort this out before moving on to timing (statically timed at 7.5 degrees BTDC right now). Engine runs, car drives. Should I be going for the 52-56 degrees of dwell or call it good in the mid 40's? Is the Bentley manual off on this? Would appreciate any thoughts.

[old vw wrench]

I usually run my dwell between 45 and 50 degrees.
I am using a 009 distributor.
Keep in mind that as the rubbing block wears the points
will close up. Just check the dwell and timing about every 3K.

[mark1laura]

As is usually the case I answered my own question with further research and practice. Started thinking that maybe my dwell meter was not accurate or calibrated correctly ... or the 6 volt positive ground was throwing the readings off. My electrical knowledge is limited at best. Decided to go old school and created the timing indicator pictured so I could measure degrees of crankshaft rotation. Got out my trusty 6 volt test lamp and was able to measure, relatively accurately, the number of degrees of crank rotation the points are closed, which when divided by 2 gives the number of degrees of distributor rotation the points are closed, i.e. the dwell angle. Low and behold the dwell angle was 55-56 with the point gap set at .016". My universe is back in balance and I can move on to the next issue that will no doubt soon be uncovered. Thx for the response.

[Da TOW'D]

should be 6 volt Negative ground
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[Eric&Barb]

Running later engine in 1960 walk thru panel. To get proper dwell have gone with .008", works great, and going by dwell only after that have not had to fiddle with points for about 30,000 miles. Then just pull the points to replace or sand flat and reuse.
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