Serpentine belt setup 502 conversion - 27 Advantage Victory
 

Greetings - have a 1998 27 Advantage Victory that Im putting a 871 super charged 502 - just noticed with the billet 3 belt pulley my engine will be 3" too long - was thinking about tigging in a fuel tank relief for the extra length - anyone know if the 502 / 454 mercruiser serpentine drive will shorten the over all length ?

Thoughts in general about super charging this boat ? 9.5 502 bored to 520 - has that Isky copy of the Mercury 502 cam with more lift - 114 lobe sep - Dart Iron Eagles - CMI exhaust ..holley sniper EFI dual 650's -

Recommend a drive conversion kit ? thank you

I don't think you can gain 3" with the serpentine setup. I had the same boat, I think mine was a 2000 model and had the same issues with no room in front of the engine. I love superchargers but I just ended up building a NA 540 for mine. It takes a lot of power to make that hull fast. I also had a 28 Victory that was supercharged. It is the same hull bottom but there was plenty of room between the seat and engine on that boat. I am not really sure what was different, but a call to Advantage might be in order. I don't know if he is still there, but Bob Supulvada was a wealth of knowledge on their product line and might have some clever ideas on the best way to modify the cockpit to fit a longer engine.

Currently doing this on mine...you will gain about an inch at best over the 3 vee....there is a dish on the lower pulley to line up with the accessories so it doesn't go all the way against the balancer like you would think. I am using a 500 efi serpentine setup and I will attach a pic of the lower pulley I machined an insert for to accept the lower cog pulley. For reference, the insert is a standard 2 vee setup with a few thousandths taken off the thickness....not enough to make a difference. So with losing one of the vee belts and adding the dish on the serpentine, if you gained an inch I'd be surprised really. I am doing it because I'm tired of vee belts coming off/breaking and the dust from them. Everything is lined up the way it came from merc but had been having issues with the sea water pump belt especially and I was sick of it lol

Hope this helps

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Sorry for the late reply - I have been piecing together a drive setup - mine is a 520 - was curious about opinions on the serpentive drive setups - sounds like the 502 & 496 HO/Magnum is the way to go - Im running a mooneyham 871 blower with dual holley sniper EFI .. was a V belt drive - already into the serpentine - have march pulleys on alternator, crank balancer and water pump - fabricating a serpentine pulley for the sea water pump - just got to figure out the tensioner and the belt wraps and routing .

the three belt crank billet v pulley adds 3 " - the serpentine will get me there with a 2" blower drive belt