My theory-

 If 1 lobe goes flat on break in, the entire motor needs to be disassembled, cleaned, at least new bearings and gaskets, as well as a new cam and lifters. There could be more damage from metal shavings.

That will never be less expensive than a roller cam.

Hydraulic roller leaves some horsepower on the table. Solid roller is more maintenance with checking/adjusting valves.

My choice- Hyd. Roller. 2 boat motors, 2 hyd rollers, 3rd one going together with hyd. roller.

Dan'l

You're in that tricky area where a very nice set of ported 049/781 ovals would work pretty dang good... (Ported, lg valves, etc...)... But a nice set of the small alum rectangles with a little port fluff & blend and hand valve job (not lap, but actual valve job with stones) would work also. (NEVER buy heads and bolt on out of the box... Guide clearance will always be too tight, and I have yet to see a decent, proper valve job on any of the mass produced out of the box heads... Including afr, dart, edelbrock, brodix, etc... I mean they work... Just not as good as they should... I mean, it's mass produced, that's what you get).

Personally... Since you have the lg oval heads, and based on impeller selection, boat, and intended use... I'd stick with the ovals... Do them up really nice (Typical treatment I do is full port, 2.19&1.88 stainless valves, bronze guides, hardened exhaust seats, rework and unshroud the chambers, valve job, and cc & surface). Heads done up will move enough air to support 630-640 hp. For your cam... Totally go with a hydraulic roller... Rpm range, lift you will be using with that head, and low maintance... Easy choice. With right at 10:1... Pump gas... And right hyd roller grind with a 496... No reason it shouldn't do better than a real, no internet bullshit, 600-630hp in the 5800-6000rpm range, with lots of low end and mid-range grunt. But... It's all got to work together. Plenty of barely cracking 500hp 496 turds floating about with mis-matched parts, shoddy machine work, and just slapped together.




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I run a 496 with iron rectangle port heads 9:1 compression a solid flat tappet cam air gap intake hp 950 Holley and for the most part runs pretty dam good I spent around 7000$ from pan to carb rpms at 6000 wot spinning a C cut impeller I've had mild build 454 and a 468  but by far my 496 has been the best build yet the crank and rods were around 2500 you get what you pay for


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Did you decide if you're gonna sell your 990's and if so when and how much? Got a guy that has a cracked head. Dm me with a price so I can relay the msg


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