Compression question

[WaveDemon]

that motor is getting re-re-rebuilt now to go in my sj. I'm putting bigger domes in it this time.

 

[Matt_E]

it was an enhacer with the stator not advanced.

Still, I wonder what the timing is up top.
I am thinking that running 33cc domes on pumpgas is probably made possible by my pretty conservative timing on my ignition - in other words, I think the enhancer timing on the top is still more advance than what I have.
Bah, I don't know.

 

[keefer]

According to the little graph MSD provides to show the enhancer improved timing curve, the advance is the same as the stock as it nears 6k or so. Not sure what the stock CDI final advance is set at. My boat was running like a raped ape when it blew like that. I am sure if I had been running some 110 octane, it would not have happened. Oh well I was younger and dumber back then. It cost me a piston, rings, and a dome for one cyl. I got lucky and it did not trash the bore.

 

[hangtime]

I just put an ADA on my ski with 185lbs of compression .Is this safe with 93 octane on a stock cylinder .
I rode it once yesterday in small surf but not very much WOT .
Until my bendix crapped on me

ADA says they recommend the 185 domes

 

[Matt_E]

Should be good for pumpgas...but right at the limit.

(I would run that WOT no problems...but that's just my personal experience)

 

[Powder]

I have been running 185 on pump gas for years never had a problem.