timing

[sunbird96]

how important is it to retard timing when using 87 octain fuel

 

[bjcsc]

Re: timing

The level of importance is directly related to your compression ratio. Why not retard it?

 

[Manipulator]

Re: timing

I often wondered this as well. With the price of fuel I typically go with the 87. For my boat they recommend 7 degrees advance for 87 octane. Premium or mid grade is at 12 degrees. At 7 degree BTC it idles like crap and at 12 its smooth. I went back to 12. I don't hear any pinging but could you on a boat engine? I guess you could if it were real bad. In my area there is a place that sells 91 octane at the same price as 87 but it has ethanol in it. On the water its either premium (91 no 93) or 87.

 

[bjcsc]

Re: timing

Well I suppose it is a matter of choice, but the way I see it, following the manufacturers guidelines (i.e. 87 & retard or 89+ and don't) is an investment. I don't know whether you would hear the pinging or not, but I know that the extra few dollars per tankful is worth not finding out (to me anyway). Heck, the cost of the fuel has been the least expensive part of my boat ownership experience...I wouldn't want to give up the performance with the retard anyway...

 

[whywhyzed]

Re: timing

You'll hear it.
if it's knockin, retard it or buy some 108 octane boost or equivalent.
If it's not knockin'...keep on rockin'
The 3.0 in my 21.5' foot Cuddy would sound like Mike Portnoy's snare drum until you took 3 or 4 degrees off. Can you blame it? 21.5' foot cuddy with a 3.0..guess what brand o' boat that was.....haha