Just wondering has anyone made any modification to there boats to get more air into the engine compartments. Factory provisions seem to be very resricted, I was thinking of adding another set of intake vents or opening the factory one inside to allow more air flow as we all know cooler intake temps make more power? Just wondering if anyone was explored this thanks

I've ducted air straight from the stock vents directly to the breathers and it made a noticiable in performance. I was on the edge in needing to go up in prop pitch and this put me over the edge. It may vary from boat to boat but bob teague has said that most boats are lacking for fresh air.

knot, did you build anything special to allow for water spray to deflect away? I'm thinking of doing something similar. -Jeff

didn"t see the need. Inoticed that the vents on my boat never got wet so this just seemed like a no-brainer. It works on cars so why not boats? I did nothing fancy for now, ijust wanted to see if it would work. I type like ****.

maybe I'll try simple too; tend to wanna make stuff complex

Fresh air intakes require air in & air out - a cool (cooler) engine compartment will make more power with lower heat - but the hot air needs to get out - it is as important to have an exit path for the hot air - Have a boat with big hood scoops - ran temp profile with data logger at 8 points in each engine bay - then cut 4" x 3" hole in a portion of the boat with the lowest pressure readings @ 100 mph ( also done with data logger) - engine bay temps dropped by 19 degrees @ speed

great info, thanks james - jeff

We got a first hand look at how restrictive conventional bilge ventilation is when Phil was testing a new Top Gun last year. Boat had 675 (?) Zuls. When Phil returned from making a pass and raised the hatch all of the fiberglass dust and saw dust from the cabin install at the very front of the boat had been pulled into the bilge. I'd say the motors were starving for a little air. Phil tweaked a few things and got the motors breathing and it eventually went 102mph with a pair of naturally aspirated, carbureted motors.

A buddy of mine with a Velocity will pick up 1 - 2 mph by just cracking the hatch open a little. I'd say factory ventilation is adequate at best

we added a set of vents for the same reasons as posted above. in this case we added an additional center vent to help alleviate a postive pressure issue.

well done, monstaa - jeff