I highly recommend a beehive spring kit. There is a kit around that will get you to .525 lift with no machining, and .550 with a little grinding you can do yourself. Did I mention they are dirt cheap?

Just want to wrap up this thread with results...

After waiting 3 weeks for my intake to come in, and a week of vacation, i finnaly got the boat in the water yesterday... I didn't change the cam, just slapped on heads and intake.

This is what i found for an exhaust valve on #8... no way that was sealing... compression was down to 35psi

http://www.offshoreonly.com/gallery/...19682&cat=3071

http://www.offshoreonly.com/gallery/...19682&cat=3071

now compression is 175 psi.

Boat with 3 people, 3/4 tank, and a 14x19"pitch stainless prop I was able to get it upto 56MPH (GPS) and 4700 rpm.

before the upgrade I was lucky to hit 48 mph with the same set up at 4100 rpm.

Time to throw on a 21 or 23 pitch and see what I can get. you can feel the power difference, and it is a bit louder too...

as far as the upgrade went... the oil dip-stick woudn't fit between the heads and the exhaust manifold. Had to re-bend it to come out on the outside of the manifold (not sure if they make a 1/2" spacer that fits between the head and minfold to space it out). Can't get the valve covers off without loosening the exhaust manifolds a tad to tip them away, but not a bit deal. Also lost the ignition coil mounting location with the intake upgrade, so I ended up mounting that on the rear side of the driverside head. No more choke on the q-jet, may have to upgrade to an electric one... Overall not a bad upgrade. I'm very happy so far. I'm hoping with the correct prop, minimal gas, and just me in the boat I can get it over 60mph.

Thanks for all the info. OSO is the best!!!

the heads and intake i used are:
http://www.summitracing.com/parts/nal-12558060
http://www.summitracing.com/parts/edl-2516

head and intake bolts are ARP, and i just got soem steel valve covers and bolts. All Felpro gaskets!

I have a complete vortec engine with fuel injection, and vortec heads intake cam harness. block is cracked. make me an offer

350 mag mpi setup? Include ECM?

yes, mpi l shaped manifold, includes ecm, engine ran great block cracked

Tried to PM you, mailbox is full. I'm interested in the whole motor.

i'll clean out my mail box, sorry.

Why did the block crack? Froze? Do you know where it is cracked?

Froze, side water jacket