I'm STILL using stock 502 valve covers,I tapped the breather holes out to 1"npt,screwed short/short nipples into them,used rigid conduit offsets to clear the supercharger,screwed a 1' nipple into that 8" long with a 1" coupler on to,a 1 1/2 k/n style breather clamps on it on top. I also used rigid conduit jam nuts inside the valve covers to keep everthing from loosening. After I painted it you couldn't tell :D. It mimics short track wet sump circle track motor breathers,Smitty

Ok, I gotta ask after all that what does the boat run now ?? to me the merc fuel injection is a good unit stock, but mods really are a big pain in the a#$...Rob

If you have read the whole post, I started with 7.4 mpi running 55mph... bolted on procharger and was running 65.... converted to 454MAG long block and slapped on 454MAG EFI manifold still with the Procharger. I am still being cautious, but last weekend with four people, 3/4 tank and full cooler I ran 74 mph on hand held gps.

I am hitting a new road block now... I still have stock Merc cable/hydraulic steering and the ride is getting really scary so i'm not spending to much time trimmed out at full boost cause my ass is cramping from being puckered and the wife keeps hitting me. In reality, I don't think I want to go much faster with this particular hull !!!!

Mine was scary at 80 with no steering. It chine walked real bad. The Hyd steering took all that away. Last year at 86mph it was smoooooth as Jagermiester!
Of course this year i haven't even been in the boost yet. I hope to go at least as fast.

What steering system do you have on your boat?

My boat ran 62 to 64 stock w/502 mpi,it now runs 98 mph with medium boost pulley,haven't tried the 1115 hp pulley yet and don't plan to,Smitty

I'm running imco twin ram full hyd steering all the way to helm,don't waste your time with the external system,my boat still chine walked at 75 mph-80 mph once you were no longer accelerating. The full conversion eliminated that,Smitty

I had the cylinders made and cobbled the rest together through a hydraulic supply house.

Traw

I'm in the middle of changing a few things too after blowing a stock head gasket. I'm thinking of tapping in manifold just to the right of t-stat housing. did you drill any extra holes in t-stat for exhaust water or was the 1/2 in. hose from crossover enough water to keep cool until t-stat opens . What temps were you seeing with a 120 deg. t-stat at w.o.t. ?. Ive been running no t-stat for a couple of years but want to fine tune with o2 sensors.

Greg

EYEBURN,

I would be interested to know how that works tapping into the manifold, I still have not changed anything on mine cause i'm lazy. I did drill and tap an extra hole in the front of the housing for cooling until the t-stat opens and it is fed by a 1/2 hose directly from the crossover... see previously posted pic. It seems to keep the exhaust cool until the t-stat opens. My temp guage never reads over 110deg. I still think the reading is partially false as the water the guage is seeing is mixed with the cool water from the form the above mentioned inlet I added. I think tappping into the manifold is going to give you a proper engine temp reading. Keep me posted!