85 26ft Sundancer Prop Help

[Jsnap]

If you guys are looking for some more speed why dont you just find your self a local engine builder thats good and let him go to work on that SB the perf parts are cheap cause there everywhere and ill tell you i have built some STOUT SB,s up to 700hp 400 ft lbs of tourque with a good port & polishing on stock cast iron vrtec heads a zillion cams that will put the power at the rpm.s you want it in my sleep i could get 400 hp for a 3rd of what that 8.1 will cost you no gas tank issues then fit your 3 outdirve and youll still have money left to stock the bar in the boat and invest in a nice thru hull exaust so you hear the cam bump and you breath well kinda like having a boat sleeper

 

[Tail Chaser 661]

If you guys are looking for some more speed why dont you just find your self a local engine builder thats good and let him go to work on that SB the perf parts are cheap cause there everywhere and ill tell you i have built some STOUT SB,s up to 700hp 400 ft lbs of tourque with a good port & polishing on stock cast iron vrtec heads a zillion cams that will put the power at the rpm.s you want it in my sleep i could get 400 hp for a 3rd of what that 8.1 will cost you no gas tank issues then fit your 3 outdirve and youll still have money left to stock the bar in the boat and invest in a nice thru hull exaust so you hear the cam bump and you breath well kinda like having a boat sleeper

Im not after the speed. But its nice to have the extra power/speed on tap for the rare occasion.
Building the boat for long term reliability. Decent cruise speed at the lowest possible rpm getting 2 mpg or better for heading 100 miles to some offshore fishing banks.
I paid 10K for this new 8.1 crate engine. I believe a new Merc 383ci EFI with fwc cost was 9K.
I was replacing the 24 yr old fuel tank anyway.

The 375HP 8.1 Mag has like 509 ftl/bs of grunt at 3200rpm
Thats a lot of reliable fun under the hatch. Very similar TQ to a 320 HP 6 cyl diesel.

If I was boating on a lake. Screaming around on a 400HP 383ci at 6000rpm might be OK. Break down on the ocean and you might die.

I was thinking of a partial thru hull/prop exhaust.
I think inboards have water intrusion problems with having the thru hull exhaust.

 

[Tail Chaser 661]

Thats awesome man! I know you were working though some gas tank issues but when do you think you will have it ready to splash?

Depends on how much time I spend on the computer :lol::lol:
Two weeks waiting on drive/transom. One week on fuel tank. Im kind of having fun with this, So I dont want to rush too much.
Should be by July 7th.

I was changing the fuel tank anyway. The issue was I'm going for Max range. Having to make the tank a little smaller for the 8.1 to fit was going the wrong direction. I'm spending more money then I have. So its hard to upgrade everything I want now. I'm not used to being in a position where saving some money comes before doing it right. If the smallblock lasted this season. I would have made every possible upgrade while the boats apart next year. Shifter,gauges,cables,trim pump PS ram,etc. I still might.
There's more to life then always thinking :smt017 What else can I do to the boat. :smt101
I need to just complete this project.
Then go dirt bike riding again :grin:

 

[BillyT0020]

If you guys are looking for some more speed why dont you just find your self a local engine builder thats good and let him go to work on that SB the perf parts are cheap cause there everywhere and ill tell you i have built some STOUT SB,s up to 700hp 400 ft lbs of tourque with a good port & polishing on stock cast iron vrtec heads a zillion cams that will put the power at the rpm.s you want it in my sleep i could get 400 hp for a 3rd of what that 8.1 will cost you no gas tank issues then fit your 3 outdirve and youll still have money left to stock the bar in the boat and invest in a nice thru hull exaust so you hear the cam bump and you breath well kinda like having a boat sleeper

Yeah I have to disagree. While Im sure a suped up SB could be one hell of an engine if done right, your never going to get the torque of a BB. Horse Power means nothing in a boat and is usually a by product of building the torque needed to push these heavy boats. If you want a lot of torque, you need to have the big block. 400 Ft lbs of torque is only about 50 pounds more then the stock SB 350 came with and only translates into 1" of pitch to your prop. IMO thats not even worth the transom plate and outdrive upgrade to accomodate the HP. I have a 454 Block in my garage that I'm going to build up into a beast over the next couple of years, but the BB starting point was key, atleast to me.

My .02

 

[BillyT0020]

Depends on how much time I spend on the computer :lol::lol:
Two weeks waiting on drive/transom. One week on fuel tank. Im kind of having fun with this, So I dont want to rush too much.
Should be by July 7th.

I was changing the fuel tank anyway. The issue was I'm going for Max range. Having to make the tank a little smaller for the 8.1 to fit was going the wrong direction. I'm spending more money then I have. So its hard to upgrade everything I want now. I'm not used to being in a position where saving some money comes before doing it right. If the smallblock lasted this season. I would have made every possible upgrade while the boats apart next year. Shifter,gauges,cables,trim pump PS ram,etc. I still might.
There's more to life then always thinking :smt017 What else can I do to the boat. :smt101
I need to just complete this project.
Then go dirt bike riding again :grin:

Understandable. Happy Wrenching and have fun with it!

I replaced the tank in my boat with a poly tank from Moeller but I downsized because I didn't need 100 gallon tank on Lake Erie. You may be able to get like a 90 Gallon Plastic Tank and if you ditch your Water Holding Tank you could add another 30 Gallon in its place for an Auxiliary. That would give you 120 and the space you need for the 496.

 

[Tail Chaser 661]

Understandable. Happy Wrenching and have fun with it!

I replaced the tank in my boat with a poly tank from Moeller but I downsized because I didn't need 100 gallon tank on Lake Erie. You may be able to get like a 90 Gallon Plastic Tank and if you ditch your Water Holding Tank you could add another 30 Gallon in its place for an Auxiliary. That would give you 120 and the space you need for the 496.

Thanks Billy,
Ive thought of the water tank relocation if necessary. Nice already having a filler spout already mounted also. To bad its not mounted on the same side as the gas. Moving my water heater back gives me room for a 30 gal tank on the port side next to the main tank. Tank builder said he could make a Y filling both tanks with the one filler. Going custom Alum, And having it fit the V shape of the bilge will get me a good 10 gals back also. I'm shooting for 260mi range till bone dry. And hopefully only have two fuel tanks 130 gals total.
Moeller does not have a tank that fits the dimensions next to the main tank.

I forgot to mention, The main reason I did not want to do the repower this year was.... Boats sitting in the sun. Wanted to build something to keep it in the shade. Same thing for the tow vehicle. Cover keeps getting blown off that.

Got to go to the depot now. Build a small A frame(Hoist) for the garage and a wheeled dolly for the 5.7 to sit on. Then out comes the fuel tank. Very comfy to sit in the bilge, Instead of hanging upside down in there :grin:
I need to reroute all wiring and run the wiring through some 3" PVC from dash to the bilge also.
I should start a new thread in the upgrades section when I have time.

 

[BillyT0020]

Thanks Billy,
Ive thought of the water tank relocation if necessary. Nice already having a filler spout already mounted also. To bad its not mounted on the same side as the gas. Moving my water heater back gives me room for a 30 gal tank on the port side next to the main tank. Tank builder said he could make a Y filling both tanks with the one filler. Going custom Alum, And having it fit the V shape of the bilge will get me a good 10 gals back also. I'm shooting for 260mi range till bone dry. And hopefully only have two fuel tanks 130 gals total.
Moeller does not have a tank that fits the dimensions next to the main tank.

I forgot to mention, The main reason I did not want to do the repower this year was.... Boats sitting in the sun. Wanted to build something to keep it in the shade. Same thing for the tow vehicle. Cover keeps getting blown off that.

Got to go to the depot now. Build a small A frame(Hoist) for the garage and a wheeled dolly for the 5.7 to sit on. Then out comes the fuel tank. Very comfy to sit in the bilge, Instead of hanging upside down in there :grin:
I need to reroute all wiring and run the wiring through some 3" PVC from dash to the bilge also.
I should start a new thread in the upgrades section when I have time.

Goo eal Man, although I would try to speed up the installation for the 4th of July Weekend!!

Id re-Glass and Paint the Bildge while you got the room. :thumbsup:

Man I couldn't imagine burning up 130 Gallons of Fuel in One Day!! My 50 Gallon Tank Full will last me a Month!

 

[Tail Chaser 661]

Repainting and beefing up everything.
90% of my trips are 105 miles with the old engine getting 1.4 mpg. 75 gals per outing. Thats another reason I usually stay out for three days.

Theres an offshore fishing bank 100 miles one way.
The ocean floor is 3000' deep coming up to 60'
Amazing, and that's 100 miles out to sea. Good pelagic fishing there.
Thats what i'm setting my boat up for. There is a couple of islands I can swing by on the way home. Making it a multi day trip.

Splashing on the 4th would be nice. Getting the run around chasing parts will be the delay.
Trying to get some Git Rot. Local guy wants 30.00 for 4oz
The shop that was going to do some of the labor said, Call him back in 1/2 hr. Only maybe he can get it.:huh:
Let the BS begin :smt013 Ordering online will most likely take 3 to 5 days.
Sealing the transom hole is the first thing I want to do. Then start scrubbing the bilge.
My vacuum oil change tank seemed to be working poorly sucking the watery oil. Wanted all the water/oil out of the engine. Just dumped that mess in the bilge a few days ago. Hoping most would drain out the stern hole into a bucket.
Then the rocker arm decided to lay down on the job. :smt009