347 Marine Build

I'm planning on building a 347 Marine Build for my boat.  I've got a few questions...  I'm not a diehard Ford guy, sorry.  I've built a few motors, mostly Small Block Chev's, Chevy and Cummins Diesels, 3.8 Buick, etc...  This is the 2nd 302 I've had in a boat and I really like the way they sound and the way they rev.

The motor currently in the boat is a 1993 vintage industrial 302.  I'd guess its a E7TE block, with FOJE heads.  We've put a Sniper 2300 EFI on it controlling both fuel and spark.  One odd thing about it - it's firing order is 302HO/351W

So as to leave the engine in the boat, I've picked up another E7TE block from a late 80's Mustang and am planning on putting a Eagle rotating assembly in it.  

The boat engine currently has a vee belt drive on the the front, and the alternator brackets look like early 70's units.  The current harmonic balancer has three bolts holding the pulley on.  



I need to keep the alternator in its current position because there is a heat exchanger bolted on the heads across the top of the motor.  



Question #1 - and I thank everybody in advance...  The harmonic balancer on the 347 assembly is a newer four bolt design.  The original is a three bolt.  Can I get a pulley for the four bolt balancer that will leave my alternator and water pump pulleys intact?

Question #2 - I'm assuming that all flywheels in all years had the same six bolt flange.  Is that the case?  It's important because the coupler for the jet bolts to the same flange.

Russ, welcome!  

I can't say about the crank pulley but I will say the two Windsor engines have the same (offset) bolt pattern on the crank tail.

It's not uncommon to use a HO cam in these engines.
 

There are hundreds of front pulleys for these engines.
I can't imagine there isn't a four bolt pulley with the correct offset and sheave diameters for your application.
Which damper are you using?
My buddy Bill has stacks of parts catalogs and sources from when he put together a 347 for his Cobra kit.

The damper thats on the boat is a three bolt flat faced damper.



The damper that comes with the rotating assembly looks like this one.

Right, but I don't know:

A) How the intended rpm range of your new 347 will differ from the 302 that you have.
B) What this will mean if you need to keep the alternator from overspeeding, or the water pump from cavitating.
C) The sheave circumferences you have now.
D) The offset from the back face of the damper. (Because the new one might not be the same?)

I know Bill used an SFI certified Fluidamper.

Those are all good questions!

The 347 will be a very mild build, I'm mainly worried about a strong bottom end.  It will have a marine profile grind and the restrictive "Industrial" heads on it



The current motor cant push the jet pump much over 4200rpm, I'm expecting a 347 to do a bit better, but still keeping it under 5K rpm (sustained).

I'm not sure of the sheave diameters, it looks to me like these are stock early model Ford truck parts.

Your last question is the one I'm worried about. What is the offset... :)

Luckily I have a couple of spare dampers, I should be able to measure it.  Since the original damper is on the boat, I'll measure from the front seal surface to the front of the damper and compare it to the four bolt dampers I have in my garage.  I'd assume that the seal rides in approximately the same place on both dampers, so I should be able to determine the offset difference.