I just bought a 26ft cat with a 496ho...still trying to dial everything in. with 4 passengers I am turning 4500 rpm with a 26p, bravo 1x, 1.5 gears and getting 65mph. My plans were to install headers and lab the prop. When I was installing the headers I noticed a ripped boot on one of the plug wires. This could have been there already or I may have done it when installing the headers.

I have a few question...please help:

could this wire problem cost me 400rpm?

Could I repair the rip in the boot..if so how?

Is there anything special about these wires since they cost $500 for the set from merc?

can I use aftermarket wires like MSD marine?

I dont see any reason what-so-ever that you couldnt use an aftermarket marine wire... IMO MSD is the best made. Forget 500 bucks. That is sheer gouging.

I do not know much about the 496 motor but I do know that $500 is outrageous for wires. I just purchased a complete MSD ignition system (box, billet distributor, wires, and coil) from Jegs for around $750, so $500 for wires is unimagineable!

I have a few question...please help:

Could this wire problem cost me 400rpm?
Possibly.....But....have you heard the motor running crappy? Is the wire/s really having an impact? In reality if the connector has contact and delivering spark without arc, there shouldn't be a problem. In a pinch if so, wrap electric tape arouund the boot to prevent arc.

Could I repair the rip in the boot..if so how?
See above.

Is there anything special about these wires since they cost $500 for the set from merc?
Wow...I doubt it...Honestly why would the need be any different than the automotive version in terms of coil to plug demand?? Remember, if it's got marine associated with it, the price jacks up. Volts to plug is simply volts to plug.

Can I use aftermarket wires like MSD marine?
Maybe you can replace the one bad wire with a Vortec truck 496 (8.1L) wire????? since the bottom line is delivering the appropriate voltage to the plug which I'm sure is no different than the truck version, in theory why not????

I'm no expert, but is my logic askew?

Yeah it suprised me that the 496 ho wires are $500 and the 525efi wires were only $125. I just thought that there must be something specific here

If you can, start the engine at night, give it a rev and have a look. You will see sparks flying around if it is arcing. If there are no sparks, chances are it is OK.

Don't know about the 496 but I tried to get away from paying $500 for a set of Porsche 911 leads and purchased the 'best' aftermarket I could find. The engine wouldn't even idle. Paid the $500 and running smooth and hitting the redline effortlessly.

The 496's have the coils mounted on the valve covers with short plug wires don't they? Maybe the $500 pricing includes the coils.

$430 at mercruiserparts.com
What a rip off. I'm headed outside to look at my boat and truck now, I'm willing to bet the GM 8.1L wires are the same. Then you could also just buy 1 wire.

No coils aren't included for the $500.

Nope, not the same as the truck wires. The Merc wires are much longer to go around the exhaust. You might be able to get them at a GM dealer though. The wires on my motors say AC Delco on them.