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Big 4 Model 1 1935 timing

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hi,anyone know how to set up the valve timing and ignition timing on my 1935 big 4 model 1 633cc side valve? engine was in boxes and nothing marked.exhaust cam has eu 14 1/2 p on it,inlet cam has19 p on it.all my books are useless. lucas mag model no h or m 01l. any info would be appreciated ,diagram would be ideal , regards martin. e mail address martcll@hotmail.co.uk if required.

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Martin

Franks lists the following for 1932, and doesn't amend it for the following years. Roy Bacons Norton Singles has the same figures.

ignition at 1/4" btdc

inlet valve opens 5/16" btdc

exhaust valve closes 5/16" atdc.

If the cams weren't marked at disassembly (my 16H has corresponding pin marks for pinion/cam alignment) then trial fit, and check measure are the order of the day.

Best of luck.

Iain

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Previously wrote:

Martin

Franks lists the following for 1932, and doesn't amend it for the following years. Roy Bacons Norton Singles has the same figures.

ignition at 1/4" btdc

inlet valve opens 5/16" btdc

exhaust valve closes 5/16" atdc.

If the cams weren't marked at disassembly (my 16H has corresponding pin marks for pinion/cam alignment) then trial fit, and check measure are the order of the day.

Best of luck.

Iain

many thanks for your help,regards martin.

 



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