So I picked up some 14-71's with blowers shop inter coolers. How much boost will I make before detonating a 9.6 static with a 254 264 @50 .632 lift 112ls cam ( basically a crane 691). Not looking to make 1200 hp here, just looking for 800-850 hp. Motors make 650 in there NA state. Leaving compression and quench we're it is after talking with several local builders. Being told I can make some decent power with my current compression and turning the big blowers slow and intercooling. Thoughts???

Aluminum heads I assume. I'm surprised you didn't just do a 800 NA build. Regardless back to your question 3-4 pds max I'd say. I'm sure some will say more and have done so without issues but I personally wouldn't go any more than that on marine engine. What kind of boat?

Yes, aluminum heads. 28' daytona eleminator tall deck.

Sounds like a good E-85 build and crank up some boost.

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well my first thought was 5-6lbs,,run the daytona boxes w/ knock sensors.or go full on efi.

Rob, you should be able to 4-5lbs of boost, on 93 octane, and meet that power goal. A good ignition with timing control, and watch the fuel mixture, and should be fine. i have a friend who's been running nearly the identical combo, without intercoolers, 4lbs boost, for 10 + years.

They will be tuned on the dyno to be safe, and then rechecked in the boat. But I am just curious because all of the compression to boost ratio chart says 4 pounds is about Max maybe 4.5. However, they don't take into consideration big blowers, inter coolers, aluminum heads, and 100 degree block and head temps. My local builder thinks we will startabout 5 pounds and then inch it up to see we're it starts getting close to being on the edge.

I figured I'd be on the low side.

Its very possible that you can run more boost. However, I can't in good conscience , say "go for it" lol, never tried it myself. Realistically though, it shouldn't take much more than 4-5lbs to hit 800-850hp with a 598, assuming it has decent set of heads on it.

I did run 7psi without an intercooler, with 9:1 and aluminum heads, never had an issue.

MT what your static cr? Seems like you were running 7-8 pds boost. Also what's opinions on intercooler chillers if your not running long distant wfo runs. Majority cruising etc and under 3k. Thought you did some air temp testing with/without.