$30 surf exhaust

Sweet!

So do you have any changes you plan?  Or are you good to go, no reason to change?    Man it seems so simple.  

after the initial trial and error, at this point i have no changes planned unless i think of a better way to laterally secure the exhaust than the galvanized wire (not pictured).  it's definitely a worthwhile mod for the price.

How about a strong bracket to the middle of swim step? 

How about cutting the underwater outlet at the same angle as FAE? 

my first go-around had an aluminum bar that is fastened to the platform brackets and had pvc pipe hangers attached to it and around the pvc, but the angle wasn't horizontal enough to keep it from falling off.  looking at FAE's design, they have a rod acting as a lateral support so someone could definitely add that to keep it from coming off.

oh and as far as the angle of the outlet goes, the pic shows the initial test fit but it is now angled much like the FAE design.

Do you have a parts list for this? I’d like to build one as well.

i will get you one this weekend including measurements, though your application may be different depending on how far your exhaust pipes are apart.

1 hour ago, jtryon said:

i will get you one this weekend including measurements, though your application may be different depending on how far your exhaust pipes are apart.

I wouldn't mind seeing another finished pic also, I'm so torn about doing this, quieting down the motor would be nice almost, but I also love the noise. 

i love the sound of my 351, but the benefit of no fumes while surfing greatly outweighs the cool factor of the sound of the motor IMO.

i'll snap some more pics this weekend for you as well.

On 5/3/2018 at 9:26 AM, jtryon said:

i love the sound of my 351, but the benefit of no fumes while surfing greatly outweighs the cool factor of the sound of the motor IMO.

i'll snap some more pics this weekend for you as well.

I went ahead and made one. Haha

sh#t dude, that looks better than mine!  how did you secure it to the output flanges?  and did you use PVC cement between the pipes?  i ended up drilling a pilot hole in each pipe then screwing in a couple short stainless screws where each pipe meets to keep them from coming apart.  worked great.

I actually like that black pipe look on the black boat, looks sick ?

As I'm absolutely killing myself on a stainless surf pipe project I'm starting to feel stupid.   This stuff looks great.   Nice work.   I dig the black too!    How's the spray on these with a round tube vs oval?  No big deal?

i noticed a little bit of spray above surf speeds so i built a surf flap to knock that down (google "duffy surf flap" for the original idea).  it actually cleaned up the surf wave as well.  it's a horse stall mat that you can get at tractor supply company and cut to fit your boat.

What do you guys think about this up/down exhaust routing? 
They do that to prevent wash back to engine? 
Would it be worth adding a flap on outlet on your PVC pipes to prevent water sloshing back in? 

That is 2018 Supra SL BTW

19 minutes ago, BBSurfer said:

What do you guys think about this up/down exhaust routing? 
They do that to prevent wash back to engine? 
Would it be worth adding a flap on outlet on your PVC pipes to prevent water sloshing back in? 

That is 2018 Supra SL BTW

It can go up first and then down.... as long as gravity still brings the exhaust/water lower than where it started.   For that I would use want a flapper and also you need to drill a small hole at the elbow by the transom.   For the water that gets trapped.   The FAEs have a drain hole at the lowest point outside the boat since they curve up in many cases

This is what I've struggled with on my exhaust... the wedge makes you go up and around... using conventional methods.

9 hours ago, jtryon said:

sh#t dude, that looks better than mine!  how did you secure it to the output flanges?  and did you use PVC cement between the pipes?  i ended up drilling a pilot hole in each pipe then screwing in a couple short stainless screws where each pipe meets to keep them from coming apart.  worked great.

I actually like that black pipe look on the black boat, looks sick ?

So it's white pipe spray painted black for what it's worth. I had cement to use but I ran a 3 stainless screws in each joint and felt like it was solid. The idea was to test then add it, I may skip it. 

I will I'll have to re tool the output flanges, mine are 3" and the OD of the 3" pvc is closer to 3-1/2". I used the flexible coupling for 3" pvc. To make up the difference I used another coupling that was wrapped in a thin piece of stainless, I cut out the excess. I was going to add a couple screws to those and ended up breaking my bit. Anyway it popped off the flanges and I lost those parts, I'm going to come up with something else. 

I did not get to do any testing tonight, with weight in the boat so I can't comment on the spray at surf speeds. At higher speeds I noticed a fair amount of spray , but looked to fall closer to the boat then where a rider will be. 

Im thinking of heating and forming the pipe more like the shape of FAE. 

On 5/3/2018 at 7:18 AM, jtryon said:

i will get you one this weekend including measurements, though your application may be different depending on how far your exhaust pipes are apart.

Thanks. I guess I’m most interested in how you attached to the exhaust ports. The rest of it looks pretty straightforward.

both yours and TFreeman’s look really good.

To attach them I used PVC cement, but found that the down pipe turned outward a little bit after a few times out. To fix that I drilled a pilot hole in a couple places on the down pipe and screwed in a couple short stainless screws. I did the same with all of the other joints to keep it from coming apart at all. Here’s some pics:

Here is a couple of the surf flap to knock down spray

On 5/5/2018 at 10:36 PM, MC205v said:

Thanks. I guess I’m most interested in how you attached to the exhaust ports. The rest of it looks pretty straightforward.

both yours and TFreeman’s look really good.

This is what I rigged up for my 2nd attempt. 

Since the soft eshaust hose is about $20 a foot and I have to order it, I'm trying to use the pvc stuff to attach it. The 3" pvc fits snug over my existing 3" flange. I added a few set screws to keep it on. 

then I double clamped on the flex coupling. 

im hoping this works. Also I changed the tip to this one

i heated the pipe pipe with a heat gun and clamped it in to shape. Once it cooled off I cut a 45* on the end

*****edit: I added some rivets through the hose clamps for good measure. But this design worked, stayed on and there was significantly less spray with the shapes pipe then before. 

I mean... that looks better than the prebuilt product people are paying $500 for. And the wye fitting you used looks like it will allow better exhaust flow, too (as opposed to a tee fitting). Well done and thanks for sharing. Will have to do a closer assessment to see if this is doable on my MC 205v. If it is, I’m definitely following your design. Thanks!

On 5/7/2018 at 1:12 PM, TFreeman said:

This is what I rigged up for my 2nd attempt. 

 

Since the soft eshaust hose is about $20 a foot and I have to order it, I'm trying to use the pvc stuff to attach it. The 3" pvc fits snug over my existing 3" flange. I added a few set screws to keep it on. 

then I double clamped on the flex coupling. 

 

im hoping this works. Also I changed the tip to this one

 

i heated the pipe pipe with a heat gun and clamped it in to shape. Once it cooled off I cut a 45* on the end

 

 

*****edit: I added some rivets through the hose clamps for good measure. But this design worked, stayed on and there was significantly less spray with the shapes pipe then before. 

Do you have any pictures of your wake when cruising at 15_18mph?

On 9/2/2019 at 7:41 PM, Gravity said:

Do you have any pictures of your wake when cruising at 15_18mph?

Nope. So at the wakeboard speed the wake is fine. There is some spray that comes through the platform.

As speed increases (towards 40) the spray turns in to a rooster tail. 😂 Looks stupid

On 5/7/2018 at 4:12 PM, TFreeman said:

This is what I rigged up for my 2nd attempt. 

 

Since the soft eshaust hose is about $20 a foot and I have to order it, I'm trying to use the pvc stuff to attach it. The 3" pvc fits snug over my existing 3" flange. I added a few set screws to keep it on. 

then I double clamped on the flex coupling. 

 

im hoping this works. Also I changed the tip to this one

 

i heated the pipe pipe with a heat gun and clamped it in to shape. Once it cooled off I cut a 45* on the end

 

 

*****edit: I added some rivets through the hose clamps for good measure. But this design worked, stayed on and there was significantly less spray with the shapes pipe then before. 

Where do you get a T fitting like that?

Any long term update on this mod? 

Did PVC warp at all?

never had a single problem with mine warping.  keep in mind these are in the water, so if there was some sort of temperature threshold that they start warping, you'll never reach it because of the lake water keeping them cool.  that being said, they never even feel warm when running off a hose in the driveway either.

question for everyone: i just got a 2007 centurion with sideswipe exhaust and want to convert back to this style.  FAE offers a complete kit for $880 which includes 4 elbows (2 x 3.5”/ 2 x 4.0”)and 2 cover plates and a one-piece Y FAE, through hull, no external bracing.  their kit re-uses the stock sideswipe hoses, so essentially the engine bay parts they supply are just two thru-hulls and two elbows for each side.  i'd like to keep it inexpensive and just do my own FAE with the same schedule 40 black PVC, but am wondering how that will fare internally in the engine compartment since it won't be cooled naturally like the external piping.  sched 40 is rated for 140 degrees.  water running through the engine comes in at a max lake/river temp of 90 degrees mid-summer (let's say), and exits out the exhaust within a few seconds.  if i have a 170 degree thermostat, what temp would you say the water coming out of the engine is at the most?  is the heat of a v-drive engine bay as much of a potential issue for a couple PVC elbows as the water running through the elbows?

Id imagine it will be fine, my internal pipes are fiberglass but they don't get too hot. You could always just replace the hard pipe sections internally with 4" marine exhaust hose if you're worried about it. 

Schedule 40 is pressure rated at 140, the melt temp is much higher. You'll never have any real pressure on the pipe so the 140 is pretty much irrelevant. 
 

i would just being making the elbows out of PVC and keeping the rest the marine exhaust hose, which is the same thing FAE does for these conversions.  i attached a couple pics of what FAE sent me for their conversion.  i suppose i could use that flexible rubber exhaust hose for the turns instead too.

thanks for the thoughts on sched 40 ratings--i also thought that pressure had a lot to do with the rating but wanted someone to ease my mind. 🤘 

What size are those interior tubes 4"?

Stainless tubing isn't bad if you just need 2 bends:
https://www.summitracing.com/parts/vpe-13044?seid=srese1&gclid=Cj0KCQjw3JXtBRC8ARIsAEBHg4k-bXkNLDnppk5zyMf6YDpu_u0Iqi3ZagQDdnA9zqDqaFLlTgsDMuoaAnaWEALw_wcB

6 minutes ago, SONICJK said:

What size are those interior tubes 4"?

i need to measure but they are either 3.5 or 4".  mine would be a little different than the pics because i have a catalytic convertor, so it might just be one bend after the cat which would attach to the thru-hull exit.  i didn't even think about buying a pre-made stainless elbow...that's a great idea to keep the engine bay a little cleaner looking of an install.

I don't know why FAE uses those shitty looking pieced together elbows rather than just buying mandrel bends. Just trying to save money I suppose. They are crappy for flow though. 
In a reasonable quantity mandrel bends are cheap

On 5/7/2018 at 4:12 PM, TFreeman said:

This is what I rigged up for my 2nd attempt. 

 

Since the soft eshaust hose is about $20 a foot and I have to order it, I'm trying to use the pvc stuff to attach it. The 3" pvc fits snug over my existing 3" flange. I added a few set screws to keep it on. 

then I double clamped on the flex coupling. 

 

im hoping this works. Also I changed the tip to this one

 

i heated the pipe pipe with a heat gun and clamped it in to shape. Once it cooled off I cut a 45* on the end

 

 

*****edit: I added some rivets through the hose clamps for good measure. But this design worked, stayed on and there was significantly less spray with the shapes pipe then before. 

Why did you use a rubber flex fitting after having the coupling already attached with screws?

Is this incase a hard strike so it will come off?

Does this look about right before I attach it together? 

Tail piece angle look ok? Length? 

Distance from taps plate good?

I would shorten the down pipe to be about level with the prop nut, and would bring the whole thing as close to the taps plate as you can without interfering with it up and down.

Its on im doing this DIY set up !!!!

I want to do this but I know it’s above my level

2 hours ago, N901 said:

I want to do this but I know it’s above my level

Nothing to it, just cut and glue some plastic pipe! 

Where did you guys buy those swoopy tee fittings?

everything was at Home Depot/Lowe’s 

On 11/2/2019 at 6:10 PM, HammerTime said:

Does this look about right before I attach it together? 

Tail piece angle look ok? Length? 

Distance from taps plate good?

I have a Tige with the same exhaust flange, just wondering how you plan to attach the fitting to it? Thanks

On 9/23/2020 at 9:39 PM, jtryon said:

everything was at Home Depot/Lowe’s 

Thanks, does it matter if I use PVC or ABS?

On 9/25/2020 at 12:05 PM, wet2ward said:

Thanks, does it matter if I use PVC or ABS?

i used ABS because IMO black looks better, but either should work.  the temperature properties of both are similar enough.

On 9/25/2020 at 11:57 AM, wet2ward said:

I have a Tige with the same exhaust flange, just wondering how you plan to attach the fitting to it? Thanks

I am considering screwing it to the flapper flange but haven't done it yet. I think a 4" schedule 40 coupling fits perfectly. I might use a rubber fernco fitting instead of screws.

Then add a brace to the swim platform.

4 hours ago, HammerTime said:

I am considering screwing it to the flapper flange but haven't done it yet. I think a 4" schedule 40 coupling fits perfectly. I might use a rubber fernco fitting instead of screws.

Then add a brace to the swim platform.

Ok, thanks for that. Yes, I measured and a 4" sch 40 fitting is 5" od, so will fit right in! Are you planning to keep the flappers in tact? If not, do you think there is any way for water to get in there?

I plan on leaving flappers to prevent water from getting in. FAE offers theirs with flappers also.

On 9/20/2020 at 9:06 PM, SONICJK said:

Nothing to it, just cut and glue some plastic pipe! 

I have the sideswipe exhaust though. Have to cut through the hull

21 hours ago, N901 said:

I have the sideswipe exhaust though. Have to cut through the hull

https://www.wakegarage.com/projects-archive/exhaust-modifications/centurion-sideswipe-conversion-r269/

Here's another iteration installed on a 2007 Tige RZ2.

nice, have you had it on the water yet?  i had issues the first couple times around with not having horizontal support and only vertical support.  vertically it still allows a little movement and my hoses popped off on a hard throttle up in the water.

Interesting, I visualized a vertical support being better as there is no flex. Did you have yours at an angle? Can you expand on why you think the horizontal is more effective? Thanks

with mine, the issue was the drag of the water on the downpipe, so a horizontal pull.  once i secured the exhaust better horizontally with screws to the exhaust outlets i had no issues.  it looks like you have rivets securing the pipes to your outlets, so that should be effective; if you give a good tug on both of those without the vertical support do they feel really secure?  otherwise, all that vertical support will do is rotate in an upward arc as the exhaust comes off.  if you put one more pin through the vertical support at the top though, that will keep it from being able to rotate outward, if that makes sense?