Finally bit the bullet and carried out a compression test on the Model A
Bought the compression tester from Amazon, can’t beat that for value, please click my affiliate link below (all helps :))
However the Model A needs an adaptor to fit the cylinder head as you can see below
First step removing the spark plugs
Once the plugs were removed the adapter to match the compression tester to the cylinder head was fitted. (purchased from O’Neill Vintage Ford here)
Time to start the test
On to the results
As you can see the results are very even, which other than a reasonable base figure is really the desired result. The Simmons Super Power Head will increase the compression ratio above the standard 4.22:1, and offers a claimed 5.5:1. So a higher figure is to be expected if the engine is in good heath.
More details here
A quick look at the plugs confirms that things are looking pretty normal
All in all a worthwhile exercise for piece of mind at least!