GT 40 vs Excalibur 330hp engine

[obd666]

For tone, is it really the engine or the exhaust system ( or lack of ) ?

Now, I know you won't get a rumble from a 4-banger. It just surprises me that the 350 and 351 would sound different when they are bacially the same from a combustion standpoint.

is a good point. i have often wondered why no one is offering exhaust systems for these boats, to give the 350 more rumble and tone ... and why they sound so different to begin with, for that matter

[TX-Foilhead]

Mustangs don't sound like Camaros or Vettes, but they all have shared similar sized motors. Different strokes, bores, and cams so you get a little different sound. Big blocks do make the nicest sound though and you can't get that out of any kind of a small block. My favorite boat lately has been a pontoon down the lake with a 496, the guy drives it like it's stolen and you can hear him coming from about 3/4 of a mile from my dock. If it just make a wake I'd take it, it so cool to see pontoon running in the uppper 50's.

[AirTool]

Mustangs don't sound like Camaros or Vettes, but they all have shared similar sized motors.

Exhaust system/concept still in play.

[surroundsound64]

If you really want rumble, replace that muffler with some schedule 80 PVC pipe!

[crobi2]

I'd been a GM fan until I got my GT40. The GT40 just has so much torque at low RPM it's incredible. I see why they used them up until the moment they ran out of blocks. Plus, I love that sound.

[DanielC]

I was working at a Nautique dealership when the switch was made. A GT-40 does sound different in the same boat, with the same muffler than the GM engine.

[AirTool]

I was working at a Nautique dealership when the switch was made. A GT-40 does sound different in the same boat, with the same muffler than the GM engine.

there are a couple of pre 2002 in my neighborhood. I'll ask about the engines and try to get a taste of this "rumble".

I love rumble and love even more cam lope. Too bad those days are gone.

[horkn]

You could always change the cam in a GM to make it more chunky at idle.

[DanielC]

But cams that make the idle more "chunky" are cams ground for more top end torque. the GT-40 is known for its low end torque, so putting a "chunky" cam the the GM 5.7 would make the engine torque at low RPM even worse.

[surroundsound64]

You could always change the cam in a GM to make it more chunky at idle.

Just take the plug out of the intake manifold where the vacuum pick up would go! Then that gm will sound like it's got a cam in it!

[AirTool]

You could always change the cam in a GM to make it more chunky at idle.

Without O2 sensors, changing cams will likely foul up the fuel injection and timing.

[horkn]

Without O2 sensors, changing cams will likely foul up the fuel injection and timing.

Not necessarily, but you would have to try to find out. Also, typically chunkier sounding cams at idle do lose low end tq, so that would not be a good idea as the GM's have less tq to start out with where it is needed, but you could have custom one made that would work around that issue. I feel the 330, 340 hp gm's give up the tq compared to the 351w to have the higher hp number. In some instances a higher hp will be fine and reduced tq won't be an issue, but say in a fully weighted air nautique, you want the tq down low and could care less about having another 20-30 hp.

[skinnytick]

someone told me that the GM engines use a bit of oil when compared to the Ford blocks, at least for the first few hundred hours - is this BS?

[JDC02SANTE]

Getting excited for my first full season with my "new to me" 2003 SANTE. Found this post while looking up engine specs, etc..

Anything special about the 25th Anniversary GT40? Or just the fancy cover?

[NautiqueJeff]

JDC02SANTE Just the fancy cover. Great engine though! I love the GT-40.

Are you SURE your boat is a 2003 though? The GT-40 was phased out in 2002. Some 2002 Nautiques had the GT-40, and some had the Excalibur. It would be very unusual to find a 2003 with a GT-40 from the factory.

In fact, the 25th Anniversary GT-40 year lines up with the 2002 model year for Nautique.

Post your Hull ID and some interior pictures and let's figure that out.