Pro & Cons of using an Air Box

[pcmpete]

What are the pros and cons of using an air box on your engine?

With a flame arrester in it, it should be ok for marine use.
I am thinking about for more of a 'bling thing' but do not want to hurt the performance either.
With the ducting facing forward should help in getting nice flow of clean air into the carb.
What are your thoughts?

 

[Bondo]

Re: Pro & Cons of using an Air Box

I am thinking about for more of a 'bling thing'

Ayuh,.... Whatever trips yer trigger....

 

[haulnazz15]

Re: Pro & Cons of using an Air Box

Seems like it would be easy to route those intake to your blower vents. I wouldn't be expecting any real performance gains though. The only con I could see to it is the possibility of a ram-air effect causing a lean condition, but it's a low probability of it occuring.

 

[Gromulin]

Re: Pro & Cons of using an Air Box

I'd tension that power steering belt first

 

[Kainon]

Re: Pro & Cons of using an Air Box

Facing forward also leaves it open to get water injestion, facing aft like they do with the HiPo scoops I am thinking would fair a little better, and possibly lean and still provide a cooler air as you wont be taking in from around a hot engine and stale bilge.

Dont think leaning out is an issue as the more air that goes into the carb the more fuel it should give right ?

I think you would only lean it out if you were using FI and not monitoring the A/F Ratio.

Lots of Dual In GM Air Boxes out there too.. a sheet metal shop could bend/cut one up easy too

 

[fishrdan]

Re: Pro & Cons of using an Air Box

Plumb a couple bilge blowers in the ducting and you'll have Forced Induction (joking)

My thoughts, fresh air wouldn't be pulled into the engine compartment by the engine anymore so temps in there would be higher. And, a boat engine compartment runs cooler than automotive since there is no hot radiator air being pushed in there and the exhaust manifolds as not running hot enough to fry bacon...

 

[haulnazz15]

Re: Pro & Cons of using an Air Box

More air + same amount of fuel = leaner mixture. The issue mainly only affects carbureted engines unless you have FI and are bypassing the MAS/MAF sensor. The fuel amount on a carb is set by the throttle position, but if you have a "tunnel ram" or other air collector forcing/compacting air into the carb, it will end up leaning out the carburetor unless jetted to compensate.

 

[pcmpete]

Re: Pro & Cons of using an Air Box

what about having an air exit duct too, what the carb does need it exited out. That way keeping fresher/cooler air going to the carb. In the photo above, instead of both ducts facing forward, one could be pointed backwards creating a free flow of air.

P.S. it is getting to that time of year when more ideas bounce around my head and less time on the water LOL

 

[bruceb58]

Re: Pro & Cons of using an Air Box

Why?

 

[pcmpete]

Re: Pro & Cons of using an Air Box

Why?

mainly because I boat in 100 degree plus weather and just looking to get as much cooler air to the carb as possible.

 

[jerryjerry05]

Re: Pro & Cons of using an Air Box

I think you would be wasting your $$.It wouldn't improve anything.Your not gonna go fast enough to improve airflow.
If your worried about excessive heat then run your blower.J

 

[John_S]

Re: Pro & Cons of using an Air Box

- Not enough hp to notice for a stock engine, so mainly a bling thing.
- Don't hook blower system to it. That will still need to draw fumes out of the engine compartment.
- Intake hose should not be faced toward boat occupants unless you like the sound of intake noise.
- Check the clearance around your exhaust manifolds.
- Engine will still draw the same amount of air, just slightly cooler.
- Looks on the tall side, check how much clearance you have.

 

[guyaverage]

Re: Pro & Cons of using an Air Box

Was out with some friends last year and did a before and after comparison test out on the lake with an airbox. Single intake hose, which was routed over to one of the blower vents. Zero effect on performance, no power difference at all. Up to about 2500 rpm you wouldnt even know the airbox was there, but over that and up to full throttle, it was much quieter for the people sitting in the back. We took the box back off and made another run at full throttle, and you could readily notice the increase in noise. It was noticeably louder.

It looked nice, but if your engine compartment is alread well insulated for noise, once you are underway you probably wont notice the airbox even being there.