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1970 A50 Compression #783253 09/02/19 7:03 am
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Danam Offline OP
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Any one know what normal compression is?

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Re: 1970 A50 Compression [Re: Danam] #783259 09/02/19 8:02 am
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NickL Offline
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9-1 was standard, i think they did 7.5-1 pistons as well though.

The cyclone was 10-1 or 10.5-1.

Re: 1970 A50 Compression [Re: Danam] #783304 09/02/19 7:40 pm
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Ignoramus Online Content
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I take it you mean what is the reading for the results of a compression test ?.......like how many psi do you get ?


"There's the way it ought to be and there's the way it is" (Sgt Barnes)
Re: 1970 A50 Compression [Re: Ignoramus] #783305 09/02/19 7:55 pm
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Danam Offline OP
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yes, that's what I'm looking for

Re: 1970 A50 Compression [Re: Danam] #783312 09/02/19 9:43 pm
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Ignoramus Online Content
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the most important thing is how even both pots are ..people usually say both should be within 10% .........depending , as Nick says , what pistons you are running i would say anything north of 125PSI is ok for an A50...........my a65 runs around 175 , or it did last time i checked it

engine hot , carbs fully open, 2 or 3 kicks to get the reading.

You also need to consider how often the head and or barrels have been planed (re-surfaced) and how much has been taken off in the process, what oversize you are running will also make a small difference

Last edited by Ignoramus; 09/02/19 9:51 pm.

"There's the way it ought to be and there's the way it is" (Sgt Barnes)
Re: 1970 A50 Compression [Re: Danam] #783336 09/03/19 5:08 am
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Danam Offline OP
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thanks!


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