X2......Prayers to ya Harry!

Ray

Depending on what has to be done to allow for a bigger cam you might look for someone selling a running 460 with all the hardware.

I would recommend talking to "LakesOnly" for quality Ford information.

X2...... And I'll get slammed sooner or later, but.........not to many 390 Jets out there........V-Drive maybe? "Mild Cam" is a relative term in this group.  a 305 Comp XM cam is a "mild" cam to many of these guys..............

Good engine, don't get me wrong!    Problem is, these days, it's more scientific than just that. Obviously, cams and lifters need to  (should be) be changed together, but the springs need to be at spec for the cam as well, timing set, degreeing in........ In addition,depending how big you go, is there any machining needed to seat the springs, guide clearance,  pushrods, etc, etc. FE blocks is yet another i am not real familiar with. But I DO know for a fact they can run and run HARD against the bigger displacement boys! 

Your 390 hardware should work just fine for a 428 as well. Both are rare enough these days, so I think you're better off dealing with the 390 myself. At the point of all this, a complete build would be in order , or just run it as it is until it breaks. That's what I'd do....

Ray

Modified Auto pans for cars in my previous life. Can be done, in this application I would only consider a rear sump to do so on, but honestly, drop the few bucks for an Armando's pan or a Dooley. You'll thank yourself, and me, later.

Personally, I've used a couple Milodon Jet Boat Pans with zero problems, but apparently, several others on the site have had issues. I'll leave it at that, not going to get into improper install and all that crap, but I have one running currently, and the other that is not running was NOT due to a problem with that pan.  Held 90 PSI at 6000 rpm every time. Take that recomendation  for what it's worth.

Ray 

I ran E85 once in my flexfuel truck....I got about 8mpg average. 

I paid $3.59 here in vegas. Highest I've seen it since I moved here. It was $2.80-ish no more than 4 weeks ago.

That was kinda my point! The whole reason for building this latest boat engine was cheap, high-performance fuel. and not $6.50 a gallon race fuel or AVgas...........

When I started this engine, E85 was a solid buck fitty below gasoline! I haven't even got it into the boat yet or fired and I'm getting focked.........lol. 

Ray

While I agree with a lot of info here, I have to respectfully disagree with the vacuum secondary comment...

They can be made to work and work extremely well. The problem is that most vacuum secondary carburetors are built with part throttle efficiency in mind. Once this has been tuned out of the set up, they work killer.

The biggest limitation on vacuum secondary performance carbs are parts availability for tuning them to a high RPM torque application. Most of the jetboat engines of late utilize much lower venturi velocities and actually are working way out of their intended design. Which in all honesty is why really high performance jets use so much fuel ( I have been working on this on paper), a vacuum secondary system is where its headed, my buddy's EFI boat uses less fuel than it did when it had an 870 CFM Barry Grant but makes another 150 RPM.....Have not gotten my head wrapped around that one yet, but suspect it was a venturi velocity issue allowing the fuel to just run in like an overflowing toilet.

Not trying to start anything, just throwing out that there are different strokes for different folks....

GT

I concurr whole heartedly. No problems running vac secondaries, even twins too large for the application on a Tunnel Ram, really. Every time I've encountered a carb problem on my boats, or a friends, it's been vacuum leaks somewhere. Base gaskets, intake gaskets, or even carb gaskets themselves. Mechanical secondaries would have NOT fixed the problem, only hidden it.

Vac secondary 4160 carbs work very well on jets, and were original equipment on all of them. To restate the original statement that Vac secondaries "had no place on a jet boat" is not only wrong, it's irresponsible. The vast majority of Marine Rated Holley carbs out there are Vac Secondary, and I'm pretty dead set on NOT running street carbs on ANY boat. There is startling evidence as to why, and I'm not gonna get into that, though I know many of you are running street carbs on your boats with no problems............yet.......... 

Ray

Relax! The stickers will come!  B-Rads got a one man operation going and sometimes, well,,,,,,,,,lets put it this way, there are members that waited a year for them when things were a little crazy at the SCJB HQ.........

Pretty cool of ya to be excited to sport them all the way in Huskerville! 

Ray

Booked my RV site today they put me in the canyon?, sounds ominous ,arrive sat probably stay 4 or 5 days

Gord? Really??? NOW I gotta try and make this...........Jeez.........

Ray

I ran mine on Moo identical to Nordies. But on Pickle, was easier, and more correct, to not fock up the hull by running it over the transom. Actually worked out and looks cool that way. Can't seem to find a pic of that though........Tom at JBP asked me to do it that way and sent me a cable long enough to do it. 

Ray

If you're serious about doing it, I've got a set of Mahle Blower pistons for one.......

Ray

T stat housing on most Fords I've seen in a jet boat is a flat piece of aluminum. I happen to have a few of the weird ones that must have been used for logs here. But the flat one is usually drilled and tapped and the temp sending unit threaded in there. You can make one of those easily enough. Post up some pics and we can plumb it for ya! 

Are you talking headers or OT pipes?  WTF is a "wetstack"? 

Ray

Boy are you in for a LOT of education. Granted, it's a tiny blower, and little to me is my 6-71! But still pretty damn efficient at what it will do.

At the RPM these boats work at, do yourself a favour and go 4 bolt, Minimum, Forged crank at minimum, and some damn good rods. You not only have to deal with the increased cylinder pressures on the compression side, but the significantly increased violence after the ignition side within the cylinder. Then theres the (relatively) minor issue of increased strain on the crank to drive the blower at speed...........Cap walk will break cranks!

It's really basic physics how it all works, but just simply looking at any V-8 engine should tell you that since all the pressure, violence and action is from the top side of one, the bottom better be strong enough to handle it. 

FWIW, splayed caps are the greatest thing I've ever seen! They originate from the very rare 340 T/A Mopar blocks that were derived from top fuel Hemi's. If ever there was a factory block asking to be blown, it was the 70-71 340 T/A block! 

Ray

     Here you go. Looks like an Enderle linkage  sounds like you just need some fine tuning.

Linkage looks like it's installed properly, except for the homemade throttle cable mount bracket. Nothing wrong with homemade, mine is as well, but yours is a push throttle and I'm betting that bracket flexes like a mother when you hit the pedal!    That would explain the throttle lag at the pedal. Check if the cable is mounted properly on the pedal end as well.

Ray

I have a feeling Ray would buy all of our boats if he could!   

LOL! Probably, But really the only floats on here I'd buy now is Boosts or MadSkillz! if I could afford 'em...........

Ray