Changes in timing for modern gas.

[ferguss@bellsouth.net]

I have a 78 Evenrude 140.<br /><br />According to the clymer manual I need to set it for 28 deg of advance at WOT. But there is a note about retarding it 4 deg for ULP. Is this the case? Or would I benefit from setting it to 28<br /><br />Have set it for about 24 deg which seems to be ok. Plugs look ok. This gives me about 5200 to 5500 rpm at WOT depending on the load and air temp, using regular gas.

 

[Dhadley]

Re: Changes in timing for modern gas.

24 is OK but I would rather have it to at least 26. When we set up a motor like yours we will try it at 24 like you have it. We then move it to 26 and retest. Most times it will slightly pick up some performance. Then we test at 28. Most of the time we see little, if any, improvement so we go back to 26. <br /><br />Your top rpm is a little low. I would suggest to get the RPM's up (experiment with the X dimension to "loosen" it up). We look for 5800 with an average load. Use FRESH 87 octane, good oil and Champion plugs. I use (Q)L77JC4's in all my crossflows.<br /><br />By reading this board and your manual you already know about decarbonizing and the importance of clean carbs. <br /><br />Good luck!