Hey Guys,

Can you please give me few tips on how to get rid of the cylinder wall & piston crown, etc etc carbon/soot buildup?
I know I can pour little bit of water in the intake of fully warmed up engine.
I'm wondering whether there's more effective method/chemical I can either pour
into the intake or add to petrol to brake down all the carbon soot crud from the engine bore.
Of course, I can pull the cylinder head out and do a manual scrubbing, but that bit too much work for me right now.
Compression readings are bit too high(180-190 range) on all cylinders & I can clearly see soot on the cylinder wall when I point a light at it through the spark plug hole.

Any tips, advice are very much appreciated.

thanks

P.S. Vehicle is an RB30 Patrol, carby.