LS1 MOLESTER

330HP stock engine.
Would i see any gains from a straight through hull exhaust?

Griff

Most likely you will see a gain. Probably 100 or so rpms.

LS1 MOLESTER

can i get a ball-park number for the cost of buying and installing a run of the mill thru hull system?

Griff

All you really need is the exhaust hose and a pair of exhaust tips--probably about $300. You can leave the Y-pipe in place and cap the ends. Then you need a hole saw to cut the holes for the tips. Get a transom template so you can cut the holes in the proper location. If you want it to be a switchable/silent choice system then you will need some diverters and it will get a lot more expensive.

Kidnova

I had a 7.4/330 in my boat when I 1st got it. I'd get another +,-150 R's and 1-2 more mph when I flipped the switch from thru prop to thru transom.

Like Griff said, if you do the install yourself be sure and get a template to locate the transom holes. You want the "standard Bravo" location (that the right name for this you guys?). Previous owner, or installer, drilled the transom holes about 3 inches higher than standard on mine to make up for the 3 inch spacers between the manifolds and risers in the Merc exhaust. Now I have a set of KE's sitting in my basement that I can't use, until I plug the existing holes, and drill out new ones

mats

My guess is that you may gain 100 rpm at the most. The most significant difference will be the noise, which is a matter of taste. Having unsilenced through hull exhaust 100% of the time is to many people really tiresome . An option would be silencers and/or cutouts. But then the $$ starts rolling....

cuda

You can usually find a good set of diverters pretty cheap. I was going to buy a pair one time for $150, but I went a different direction.

Hydrolift

Same engine same result.