I purchased a boat a few weeks back with a stock 90 350 4bbl motor. the stock Q jet 650 is being rebuilt now and I was thinking of upgrading from the restrictive cast iron intake manifold to an aluminum piece. I contacted my local marina and they stated I would be able to use the AL piece as the motor is not subjected to salt water. The heads are 87-95 pattern spread bore style carb. Max WOT RPM specifications state 4200-4600 so I was thinking an idle to 5500 unit would be best. I've seen the Edelbrock Performer , Holley Intake Weiland and the Summit unit all at good prices. The summit is attractive as its only 125 bucks, but I was wondering is the Performer any much better? Thanks!

 

okay so we are talking boat here... I/O? sterndrive what? not the same thing as a car... unless you are looking to start changing props also i would leave the engine alone... as an increase in HP of anykind will change the WOT RPMS as the prop will be to small not enough pitch... to hold the engine back off the rev limiter

so unless you plan on dragracing your boat it really isnt worth it

 

The 87-up heads and QJet carb will limit your intake choices somewhat, but performance versions do definitely exist. The Edlebrock Performer #2104 would be a bolt-on and give better performance than a stock intake (from mid-RPMs up). The Weiand Action+Plus #8024 would be the competitor to the Edlebrock and is the same basic deal. BUT you can buy the Summit house brand intake, SUM-226016, which is the EXACT SAME intake as the Weiand but with a Summit logo on the intake instead of the Weiand logo. Weiand makes all of Summit's house-brand intakes.

All the intakes I listed above are for 87-95 bolt pattern heads, non-EGR (since boats don't use EGR) and take a QJet carb.

 

Boat is a 90 Chaparral 350 Mercruiser IO. I am already above my RPM so I know a new prop will be in order. Currently I am at 51mph at 5K, and with a little more HP and a 23P I am hoping for 60ish with around 4500K max