Is it worth the effort/money to upgrade?

Hello,

One of my winter projects is to replace the old/rusted exhuast hoses. In taking the exhaust apart, I have found a mismatched set of components. I have dual 3" risers going into a 4" collector, which then goes into a 3" muffler and then into 3 1/2" transom exhaust fitting
(dual 3" into 4" into 3" into 3 1/2").

The motors are Crusader 270's (270HP@4400rpm ish).

1. Do I just replace hoses and leave mismatched componenets? Boat runs fine and did 1200 miles last season. 3" Mufflers are rated for 160HP

2. Upgrade mufflers to 3 1/2" to match transom fitting? Those are rated for 220HP

3. Upgrade mufflers to 4" and cut out/enlarge transom fittings? Rated for 260HP or so


I rarely run above 3000k and am wondering since I have run over 5 years with 3" exhausts, is it worth the money/effort to change the old exhaust system?


Your thoughts?


Timmy B
1966 31' Chris Craft Commander

A single 3" is a bit undersized. However, as you say the boat has been running fine for a number of years. I wouldn't give it another thought until repower time comes around.

I think you'll fine the enngines will run much better is you open the exhaust to 4" the whole way back from the Y.

Our big blocks has 3" to the Y and then 4" out the back. We switched to 4" from the elbow, back to the Y, and then 5" out the back. Throttle response improved tremendously.

If you get into it, conside using the fiberglas tube in place of hose where possible...it flows better and will last forever as long as the cooling water is flowing.