That thing done yet dude?? we got a sea trial to go on!! haha glad everything is working out well brotha!! Keep me updated.

Uncle Dave,

Thanks for your support

Greg,

How are you? Yes, I know it has been a while but still hangin' in there, and i will definitely let you know when we are ready.

My close cooling kits are getting here this Wednesday, did i do the right thing by spending the extra $ ?

No question about it.

Will you be dynoing these?
Does the boat have full hydro steering?

Sitting here reading this thread and learning a lot. I too am going through this tough time with engines. I have a 29ft. Scarab, twin Vortec 5.7's, MPI fuel delivery, advertised at 300HP, 1.5 Bravo 1's, 23p Mirage Plus... One engine shattered an exhaust valve. Did tons of checking, asking, reading, and pretty sure the cause was from a riser gasket leaking.... To fix the problem ..... Going back as 383's .. parts are: Eagle rotating 400 steel crank, forged 5.7" rods., dished hyper .030 over pistons, vortec heads with match port(machineing valve guide down), holley MPI single plane intake (2000-7000), full roller rockers, comp cam XM270HR (int-.495, exh-.503, @.050 int-218 exh-224, int centerline 110, lobe seperation 112, RPM range 1500-5500. Will use stainless marine or emi manifolds. The boat ran 68 on GPS @4900, 100 gals. of fuel 2 people.... dont know what my results will be... I am going to get them dyno , one shop can do prop dyno, the other is engine dyno. I am more concerned with being dialed in right (fuel, timing), but will like to know HP/T ...... I would really like anyones honest input on this.... first engine is about half complete....

I have the exact cams in 357 Vortecs w/ Vortec Heads,1.5 Comp Roller Rockers, Dual Plane Edelbrock w/ 750 DP Holley's. Mine made 400 horse at 5200 and 435 Ft. Lbs. @3500...TQ Curve is 400 + from 1800 to 4000. Dyno runs were with automotive headers and I will be running new style MerCruiser Exhaust....so subtract 25 HP at the top and keep the TQ high.

Based on my results I'm throwing a guess that you will make 450 HP in the low to mid 5K RPM range with TQ around 450~475 Ft. Lbs.

The 383's with the same props with 900 HP in the water will run a solid 75+ predictably...biggest pick up will be in the snappiness of the boat as well as a stronger cruise with a load.

I talked to Diego this afternoon and told him if I had it to do over again I would build a pair 6.0/6.2 LQ9 based motors and run reliable N/A 500 HP....but that's the next boat.

+1...especially with aluminum heads in our environment.:evilb:

I am looking for a place to dyno these engines.For sure.
No hydr. Steering .