Offshoreonly.com - 496 mag ho

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I went Scat H-beam for rods and SRP forged for pistons when I rebuilt my 496. I went with AC Delco 41-983 platinum just like it had from factory. They went 400 hours so I figured don't fix what wasn't broken. . .

Quote:

Originally Posted by BUP (Post 4609834)

oh will add ----- I read the RAYLAR info in the link from above that I quoted. Not to sound like I need to correct them but - with DIS ignitions do not use anti seize on the sparks plugs period. Matter of fact the top 3 spark plugs makers even tell you not use anti seize.

Also he lists the Denso spark plugs. I would not use them - reason was IN THE PAST when Denso plugs were installed in new engines --- WE HAD PROBLEMS WITH THEM.

There is even some on OSO that called me with 496 engine stumble / miss running issues and the first question I always asked ---- does it have the Denso plugs installed ? When the answer was Yes - change them and see what happens, Many 496 engine stumbles cleared up after getting rid of the Denso spark plugs.

so what happens when anti seize is used? I just replaced all 16 of mine and and used anti seize on every one, I really hope I don't have to do that job again to remove the anti seize, plus cleaning it off is gonna be a *****

here is one of the issues with Anti Sieze but there is more. also some other info added. All spark manu's and even OEM engines currently want all spark plugs installed with a torque wrench plus follow the specific torque specs when installing.

NGK Spark Plugs

and I can not tell you how important the spark plug gap is for the 555 controlled engines. The fine wire spark plugs we do not touch the gap period unless it is off spec - but we just grab another new plug - sending the out of spec gapped spark plug back to NGK and or if it even a slightly defect.

We check the gaps - very easily plus look at the gaps and its related parts including the fine wire on all new plugs with a spark reader, actually with a real doctor Odoscope before they are even installed. Fixed so many rough idles and or misfires from whomever changed plugs and gapped them or even spark plugs that were not manu perfectly. Not uncommon to see this when one works on multiple boats per year.

read the NGK link above post especially about fine wire gap. Anyways I hope this helps whomever.

Thanks BUP, I actually did check all gaps just out of habit and they were all at .060, I was careful not to get any anti seize anywhere near the electrode, just a small dab, I was aware of the lubricating characteristics of anti seize when torquing the plugs down, I wasn't sure if there was any side effects while running from it providing everything is working properly