Eliminated water boxes today(straight thru)

[spaulding]

ok, I went straight through today. The exhaust is louder and may be too loud for some.

The ski seems to ride higher in the water. I have no way of testing this, but it just feels different and lighter on the water.

Today is the first day I could visibly see I was pulling on my other ultra. Unfortunately, my BOV went to leaking because I was down 2 lbs(4 marks on the guage) of boost and still managed to run 64.7.

Jason

[Aquaholic6801]

Lets see some pics of what you did

[spaulding]

I have pics I just need to edit and post.

Jason

[aussi 250x]

jason
i did mine a few weeks back and have tested alot no problems as yet with my other mods it now runs 69.7 at sea level & 68 flat 500 mtrs above.it does feel lighter on the water. when i did the exhaust it gave me only .8 mph gain but does feel stronger mid range.this mod with a computer should see better numbers.
rob.

[spaulding]

jason
i did mine a few weeks back and have tested alot no problems as yet with my other mods it now runs 69.7 at sea level & 68 flat 500 mtrs above.it does feel lighter on the water. when i did the exhaust it gave me only .8 mph gain but does feel stronger mid range.this mod with a computer should see better numbers.
rob.

yeah, I remember. Your post and the ski done by r-rated inspired me to do mine.

I have pics of the primary not installed. The secondary is a 2.25" u-bend 6" center to center.

I have no pics of it installed.

The sound is very different. It gives the ski a race sound wthout sounding obnoxious. The decibels are up there, but not untolerable.

Jason

[Hydrotoys]

when i did the exhaust it gave me only .8 mph gain

Only? that is massive on this craft.

[Beagleman62]

J.R. Sherman had the straight through exhaust on his boat. Here is a short clip. The video part kinda sucks but turn up the sound and listen to his exhaust note. It's loud but not that much louder than the R-Rated "u" pipe I have on mine.

[spaulding]

Mid range acceleration is much improved. Pictures attached. I made this with left over pipe I had from a previous project. No reducers so I had a lot of gap to fill, also the bung for the water is galvanized and I did not do a very good job of cleaning it before welding so it is really gobbed on. I ended up using epoxy to finally seal it.

Basically, I measured the waterbox dimensions and recreated it from pipe. This model is aluminized pipe since that is all I had. Next one will be made of SS.

Jason

[spaulding]

Forgot pics.

[spaulding]

Another one