Here's what I'm needing help with. Does a jet boat "load" the engine enough differently than a car to "shift" the powerband of the intake it needs?
Not sure if that made sense...so I'll try to ask another way. Say the engine in my jet boat only runs 6000 rpm, then do I get an intake for a car that is perfect for the 6000 rpm range, or does it shift up?
I ask...because I have a 383 LS1 in my boat. With a Performer RPM and carb, it revved 5700-5800 rpm, a Super Vic and carb, it revved 6000-6100 rpm. Now, with a Fast 90 intake (that is usually great in the 5500-6000 rpm range) it'll only rev to 5500 rpm. - it'll "flash" to the 6200 rpm rev limit, but then get pulled down to 5500 rpm. I'm 99% sure the issue isn't the tune, so I'm wondering if the intake it just a bit undersized?
The intake that I *think* would be good has an optimum rpm range of 7000-8000 rpm - and I know my engine will never be able to spin over 6000 rpm. But...I'm wondering if that might actually be perfect?