Has any body used a Fresh air Exhaust?

I am thinking of getting a fresh air exhaust for my boat. I want it for the noise reduction not the co2 issue.
I am interested in both good and bad comments.

Here is there site,
http://www.freshairexhaust.com/

Thanks David

Someone trying to capitalize on the media coverage of CO2. I've never seen or used it, so I don't know. Seems like you could make the exact same thing for about $100.

I second Jeff, looks like a waste of money. But have never used it. Soemone posted about it on here a while ago. Is your boat really that loud???

Im wondering how it dosent get ripped off. It seems like the force of te water would break it. I wonder how or if the have a kit ofr a single exhaust

I agree with you grant. Seems like this would significantly increase the stress on the point where it is connected to the boat. Additionally, it appears that the exhaust from two tubes out the transom is reduced to one tube that has roughly half of the total orifice size for exhaust flow. This would unquestionably have a negative impact on engine performance due to reduced exhaust flow. I would also think it may increase vibration since it appears to be directly in the thrust line of the propellor. SS does not have much give so if you hit something the cost might be very unpleasant. I think this one is a pass.

men, your boats are silent, you should remember when exhausts were over the water line, that was noisy

Im not saying its a bad Idea, I think ist a great Idea. Just wondering how it works, And how it would work on a single outlet. It looks like it connects to the swim platform to get strength. So taking the swim platform off and on might need a few extra steps
I was wondering if the exhaust tube that goes into the water would be better if it was shaped more like a rudder to cut threw the water. Its not the greatest looking add on but hell if it works you dont see it whan your boats in the water

I had an e-mail discussion with Larry Mann the creator of the Fresh Air Exhaust (FAE) system. I think it's a great idea. I was interested because I have been wanting to try a few different methods of "dropping-in" for wakesurfing, including laying on the board right behind the platform with my face about 4 feet from the exhaust. Unfortunately the current systems reduce top end speed by about 2mph, and that's 2 mph that I am not willing to give up (for barefooting). So no "dropping-in" for me.

Yes, I have one and No, it doesn't get ripped off the boat. No, it doesn't add vibration. No, back pressure is not increased except at WOT and even then, only a couple of pounds. Yes, it's designed to swing away if hit (your rudder and prop would go first anyways). Yes, it reduces the CO2 when surfing or slow idling through the 5's. Yes, it reduces the noise levels considerably in the boat. Yes, it makes backing up a little more challenging. Yes, you could probably steal the idea and make it cheaper yourself.

There is another post about it over in the surfing section. Man for people who have never seen it, or used it ya'll are ripping on it pretty good (Grant excepted). It definitely makes surfing a lot more fun, not chugging exhaust, at least with my old boat one pipe is out of the water, right in your face and the back seat is more comfortable without the cloud of exhaust hovering there.

http://www.wakeworld.com/MB/Discus/messages/87668/260077.html?1129381314

someone post a pic. my spyware program won't let me see it

Here you go...

Gordon,

I hope my post didn't sound negative? I was very interested in putting the system on my boat, I did the research and read the scientific report and feel that it's a very good system for most boats. I just cannot afford to lose any top speed the way I use my boat (I should be in the minority with this regard). It will not work on my buddies Malibu because of the wedge either, bummer.

Mike

(Message edited by mikeski on October 28, 2005)

Mike what are you complaing about top speed. You barefooted behind miy boat @ 34 MPH. So dont try telling me you need every MPH. LOL

To people who are wondering what im talking about, Last week Mike barfooted behind my boat I forgot to turn the Perfict Pass off and he was stuck with footing at 34 MPH untill he dropped, Sorry Woop's my bad.

Looks like you would have to anchor your boat out farther from shore also.....due to the lowest portion of your boat now being behind the rudder.

Greg,if you have to anchor the boat....anchor buddy!

Ed, I use an anchor buddy, but with that exhaust hanging down, you can't pull your boat in as far to board it as you could without the fresh air exhaust...just an observation.

I think this is a great product idea. Kudos to the inventors!

"To people who are wondering what im talking about, Last week Mike barfooted behind my boat I forgot to turn the Perfict Pass off and he was stuck with footing at 34 MPH untill he dropped,"

So you haven't figured out that you can cancel PP by hitting "off" twice and enduring the buzzer for a bit...?

Wow.

Justsomeguy,

If you are running wide open it won't recoil the cable and open the throttle, so he was stuck.

Grant,
Put that old PP controller in the rear hatch as a second control so I can do it myself next time!!! LOL

I put one on my Sunsetter lzi. I needed to reduce the noise as the small lake I am on is thinking about restricting boating in the morning due to us skiing my boat early on Sat. and Sun.
It reduces the noise greatly. Performance/slalom wake is not effected. Can't use wedge though.

I think I've found my off-season project!

Sorry to be such a geek but it is CO and not CO2 that is the issue.

I too am considering this during the off season. I spoke with Supra and they indicated that it was up to Indmar whether this was a warranty problem or not. The Indmar guy left me a message indicating that he did not think it would be a problem (I guess I should get that in writing though).

Anyway, given that more days are rough on my lake than not (and I'm a wimp about wakeboarding when it's rough), I find myself surfing a fair amount.

We, Fresh Air Exhaut, recently made a minor change to our system. We picked up about 1/2 mph at wide open throttle (only lost about 1-1/2 mph). This modification was also on davidgree's system. I am very pleased to hear that there is no change in his slalom wake. That's been our observation, but then again, we aren't slalom skiers.

We recently received an independent noise study that reported up to a 12db drop in noise. A 12db noise reduction is the difference from a coffee grinder to that of conversation.

We have taken the noise reduction for granted. We were so focused on Carbon Monoxide (CO) reduction (up to 90%) to save the sport of wakesurfing from the stupid 20' rule, that we overlooked noise reduction. Anyway, we did some recordings with the system on and off the boat. The results were astonishing; and the stereo certainly sounds much better.

Attached are two files with the different exhaust noise.

Without FAE -

Boat noise without Fresh Air Exhaust FAE_Off_Slow.mp3 (104.0 k)

With FAE -

Boat noise with Fresh Air Exhaust installed FAE_On_Slow.mp3 (104.0 k)

Over these winter months we will be updating our website to include these noise level studies and files and make the site easier to view. Even though installation is pretty easy, there will also be more detailed information on installation to help make it even easier. Please check us out from time to time at
www.FreshAirExhaust.com
to see the new material.

The downpipe, the part sticking down in the water, is shorter than the rudder. If you back your boat to shore, your rudder and prop will likely hit before the downpipe.

Also, we now have the single exhaust outlet Nautiques figured out and are working on designs for the Malibu Wedge and new Power Wedge.

When you download the 2 files above, if your system tries to save them as a .unk
change it to an .mp3 and it will play correctly.

Larry, very interesting product, but I have a very important question that no one seems to have addressed. Do you retain the exhaust flaps? My biggest concern would be making a quick stop and having water go up and into the engine. Which would destroy it. What have you done to prevent this?

My question is about the effect of the additional backpressure from the exhaust having to push down through that additional water in the system. Seems like that would kill performance and hurt fuel economy, especially at low rpm.

I would think that the back pressure wouldn't be effected. It is pretty much the same as going out the normal tailpipe. Just like when you back your truck in and the trucks tailpipe goes in the water.

(Message edited by depoint50ae on November 07, 2005)

There is no way that water is going to enter the exhaust system of a running engine. A V-8 engine is essentially an 8 cylinder air compressor. With a standard boat exhaust system, without the engine running, the muffler floods with water. When you start the engine, that water is blown out. If you suddenly stop a moving boat the exhaust pressure will keep water from entering the exhaust system.

All three boat engine manufacturers recommend that the backpressure in the exhaust system not exceed 2 psi. This recommendation is to prevent a degradation of engine performance. The factory installed exhaust systems we’ve measured reach approximately 1-3/4 psi at wide open throttle (WOT) but at other throttle positions are below 1 psi. Fresh Air Exhaust (FAE) generally increases backpressure about 1 psi; therefore, with FAE installed, backpressure remains below 2 psi except at WOT and then only reaches approximately 2-3/4 psi. Back off the throttle about 100-200 rpm below WOT and backpressure drops back below 2 psi.

We have performed fuel consumption tests and found no increase in fuel consumption. In one test, at 10 mph, we recorded a slight improvement in fuel consumption. We have also performed top speed tests and 1/8 mile acceleration tests and found mixed results. For example: We tested a 1989 Correct Craft Ski Nautique for 1/8 mile acceleration. The boat had 1200 pounds of ballast and 1 person on board. The average time from 0 mph to 1/8 mile was 17.7 seconds with the stock exhaust system and 17.3 seconds with FAE installed, for a 2% improvement in performance. We tested the same boat, with 3 people on board, no ballast, with and without FAE installed. The boat attained 42mph (determined by GPS) at 4250 rpm (wide open throttle - WOT) with the stock exhaust system. With FAE installed the boat attained 41 mph at 4150 rpm, for a loss of 1 mph.

Based upon our testing, it could be that FAE actually improves engine performance below WOT and only minimally degrades boat performance at WOT. Our customers are happy with their boat performance. We have a 96% customer satisfaction rate (the 4% got their money back). We continue to research FAE so that we fully understand why it works so well; but, that is the important thing: that it works so well.

Larry Mann, DC
Fresh Air Exhaust

What about putting a flap on the FAE to ensure no water could back up the exhaust sytem while in reverse?

David,

Older boats didn't even have the rubber flappers on the hose. My 1995 Nautique blew the flap off and I probably ran it for months before I noticed it was gone. As Larry said, there is really no way water will back-up into the exhaust.

For all those worried about water backing up...you shouldn't. This is a matter of physics.

Consider this:
You car is configured with the exhaust pointing forward and the pipe extends 2feet beyond the front of the front bumper. You start driving...your going 100mph down the highway...will your car stall because air is getting into the engine the wrong way? Granted this is a hypothetical situation, but the answer would be no.
Why?
Why, similar to what was mentioned earlier, an engine is essentially an air-pump. The engine is taking is "X" amount of air every second, it needs to expel that air at nearly the same rate. The only real way to stop this action is to plug one end or the other...and NO water will not plug the exhaust end. Its a liquid and influence by air and other factors plus it simply doesn't have the properties to create such a plug. All in all the engine will win in this situation and others of a similar nature.

besides, how fast are you really going in reverse, and for how long too? Believe me I have done a lot of backing up in my time, and unless someone here has figured out a way to get a tourney-style boat to backup straight and faster then 8-10mph...then you might have something...but then again I would think that the FAE people would want to see that too!

Why couldn't you just make a 90 elbow fitting out of stainless that drops just below the waterline of the boat? I'd think that would be just as affective and much cheaper to install/produce. Just my uneducated $.02