projected tip spark plugs vs standard tip

[jack avery]

Does anybody have any advice on switching from a standard tip plug, such as the AC MR43T to any of the projected tip types by Champion, AC, or NGK? This is for a Chevy v-6 in a OMC I/O. <br />Are there any problems to watch for, or do they work well?<br />I'm looking for a solution to cold fouling plugs and the projected tip looks promising.<br /><br />Thanks

 

[ODDD1]

Re: projected tip spark plugs vs standard tip

rumbler, you are correct in asuming projected tip plugs will help low speed plug fouling....the longer insulator [and greater exposure inside the combustion chamber] will run hotter tip temps and be less likely to accumulate crud......the other side of the coin is that fully loaded trip back in after fishing.....WOT with a heavy load, possibly not acheiving minimum WOT rpm's......the detonation angel will be listening, maybe even gift you with a set of melted plug tips, or even [gasp] a set of holed pistons!<br /> many charter boats on michigan run these plugs because of the extended trolling they do..sometimes 700-800 hours a season...they do last longer, but you must always be mindful of the heat/workload you put on the motor....

 

[jack avery]

Re: projected tip spark plugs vs standard tip

Thanks ODD1. In my case the boat sits for weeks at a time waiting to go fishing. In a good year it gets wet six or seven times. With the AC MR43T's that it calls for, the engine has a tendency to get the plugs wet, and thus start on less than six cylinders. After a while they warm up and all six are firing. During the day I'll do a lot of drifting followed by short runs of less than five minutes to start the next drift. Often times the plugs just don't get a chance to really warm up very well. <br />My trips back to the dock are usually less than 45 minutes, and I run around 3500-3800 rpms, well under the specified max of 4300-4600 rpms. <br />Is there another plug that might work better?<br />By the way, my engine temp rarely if ever goes over 175 or so, most of the time it is around 160.<br />Thanks for the info.

 

[petryshyn]

Re: projected tip spark plugs vs standard tip

hello rumbler<br /><br />If it were me, I'd go 1 heat range hotter on your plugs. eg MR44T. Take them out frequently and inspect them for overheating for the first few weeks.