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So ive done a test at home and got some interesting results. I have some ideas but wanted to get some analysis from everyone as to why my results are like this and causes.

 

I got, front to back

 

167

160

150

140

157

145

 

Thoughts?

 

Thanks1524024723762

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Up to 10% variation is quite normal. Yours is a little bit over that but still pretty good for a +20 year old engine.

 

Heaps of things can cause the variation. From ring, bore, valve guide, valve wear to name a few.

 

I would honestly be happy with that and not be investigating any further. If you had 1 down to 110-120, that would be more concerning.

 

 

Ok good to know things all seem fine. So there is nothing specifically causing cyl 4 and 6 to be lower than the rest then? I know if two joining cyl are low it can be head gasket related, but wasnt sure if there is a typical reason for this.

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