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MG MGA - Timing

I was fortunate to find a almost new "adjustable timing light" at a garage sell.Now, I need to know what is base line for "dynamic setting" for my 1958 MGA with the original 1500 engine. Engine has been rebuilt with stock internal components. At present I have set timing "static" 7 deg.. and than adjusted the distributor to get the bulb to light.. Engine runs fine, starts quickly, has no run on, no pinging.
But, I want to check out dynamic timing. I have a book"MGA-MGB" published by Clymer, second edition dated May 1977, that has a table(7) for tune up specs.
gives ignition timing for 15GB engine (which is mine)static 7 deg BTDC and dynamic(stroboscope) 11 deg @ 600rpm. But, have also found these numbers from past inquires (2 yrs ago) at this site. 20 degrees @700 rpm, 20 deg.@800 rpm, 20 deg.@1500 rpm. So, whats a good base line?? My car idles fine at 700 or 800 rpm but doesn't like 600 rpm.. I use 93 octane fuel. Thanks as always. Mike
Mike

Mike

With the vacuum pipe disconnected I set mine at 32 - 34 degrees at 4000 RPM.

Steve
Steve Gyles

Depends on whether you are running on unleaded or with lead substitute
dominic clancy

A couple of trains of thought here. As mentioned above set dynamic timing after distributor has reached full advance and what it is at idle is not a concern. My personal method is to set timing to specs then go out and find a long hill and floor it up the hill in 3rd gear. Keep advancing your timing until the engine "pings" then back it off 2 degrees. Now your particular engine is set for optimum timing with the brand and grade of gas you use.
Mitch Smith

OK, found a "base Line" Got this info from University Motors, web site (John Twist). 20 degrees@approx. 800 rpm(idle). Then go for a road test.. So, Mitch you're right on. Thanks again Mike

Oh, forgot to mention there is a article written by John Gunnell. after a visit to John Twist in Feb 2006 at University Motors. Article appears in "Auto Restorer" dated Feb. 2006 and titled "English (car) 101"
Mike

This thread was discussed between 22/05/2006 and 24/05/2006

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