Just some food for thought on 460 builds. These builds were put together by Paul Kane (LakesOnly on the 460 forums). He's got a lot of time invested on the dyno and what works and doesn't on the Ford 385 series engine. I just thought it might interest you guys to read a few tried and proven 460 jet boat builds. I have found over the years that his horsepower numbers are conservative on these builds.
Per Paul Kane:
I’ll start with a motor that is essentially just a massaged over 460 that addresses key points of improvement and also increases pep. I like to think of this build as “how the motor was intended to be by the engineers at Ford…before the bean counters and EPA had any influence over the engineering drawings (and compromised them).†Also taken into consideration will be marine application of the engine.
My only concern about these builds is that often the end user is so elated over the results that they subsequently regret not making the engine with a little more power. For this reason, I’ll follow the first build with another that has a few changes that will ad some more horsepower.
Build #1:
· 460 short block with stock rods (ARP bolts) and SRP flat-top pisons. (about 9.3:1…9.6:1 with zero-deck)
· Double-roller timing chain
· Comp Cams Kit with XE262H 218/224@.050†.513â€/.520†110LC. This cam will work with stock D3VE valve train components; snap-on valve stem seals MAY be required for clearance but not likely.
· Intake and exhaust bowl blending of D3VE cylinder heads. Also, exhaust port of D3VE cylinder heads should have the smog bump mostly removed and the exhaust manifold bolt protrusion (bulging from port wall) blended down as much as can be reasonably done so as not to be a flow obstruction.
· Your Edelbrock intake with a Holley 850 #4781 mechanical secondary carburetor.
· Aftermarket dizzy or recurved factory Dura Spark electronic distributor.
· OT headers.
· Zero-deck recommended; .005-.010 acceptable.
The above build should put you in the 360-370Hp range. No heavy substitute pistons! The lightweight SRP flat-top pistons are important to use with stock rods. These lighter flat-top pisons, combined with the impeller-restricting 5200 rpm max, will allow your stock rods to last the life of the engine. This engine should be essentially maintenance free for the life of the engine (just seasonal tune-ups) . The compression ratio will allow you to run pump gas. Special Note: If you are already seeing 5200 rpm with your current (rebuilt) engine, it may be that this motor will not offer you any performance benefit, BUT this must be confirmed by evaluting the components inside your current engine (at teardown).
Build #2:
Same as above but with “D†cup 20cc dish top pistons and D0VE heads
with bowl blends and smog bump removal. (10:1 c/r with 0 Deck).
Roller rockers and guide plates for valve train.
Comp Cams Kit with XM288H 244/254 .580/.585 112 LC.
The above build should put you at around 500HP. 92 octane pump gas required; blending fuel may be required depending on other criteria.
"I chose to not use the D3VE heads in Build #2 because the resulting 9.5:1 c/r will be sub-par for the camshaft utilized. Engine will run okay, but not a perfect overall combination. Sure, you could get dome-top pistons and attend to compression, but then you will have a heavy piston on those stock rods, remember? So then now you need Eagle SIR rods. Etcetera. Not cost effective for the power increase."
In my further review, we could say that Build #2 could indeed use the D3 heads with the valve train mod. HP would come in at 460HP rather than 500HP due to the lower c/r...that's all.
Build #3:
· Stroker rotating assembly with 4.3 crank, 6.800†Chevy H-beam rods and forged pistons, bearings and rings. .030 overbore will be about 521 cubes, .080†will make about 533 cid, but bore only as much as necessary for clean-up (to save future overbores).
· Main stud kit.
· 22cc “D†cup pistons 10.5:1 c/r
· D0VE heads ported as above.
· Solid lifter cam kit about .600 lift and 275* intake/280* exhaust duration @ .050" Roller rockers.
· Aftermarket dizzy or recurved factory Dura Spark electronic distributor.
· Holley 850Dp and aluminum single plane intake
This kit will put you at 600HP assuming excellent tune. Occasional valve lash adjustment necessary. 93 octane (Possible blend fuel) minimum
(This is Basiclly the build I started with for several reasons. Horsepower estimate was low proven out by the RPM against an aggressor B impeller. 5950 Rpm=630 hp according to the Jacobs pump calculater. Followed by a larger custom grind cam after first build. 6150 Rpm=689 hp according to the Jacobs pump calculater. Per ESA)
Build #4:
Same as above but with TFS aluminum heads. 650HP minimum, with the potential for way, way more with cam, compression and carb changes (800HP possible).
Build #5
· Stroker rotating assembly with 4.3 crank, 6.800†Chevy H-beam rods and forged flat-top pistons, bearings and rings. .030 overbore will be about 521 cubes, .080†will make about 533, but bore only as much as necessary for clean-up (to save future overbores). 10.8:1
· Main stud kit.
· D3VE heads as in Build #1 plus valve train mod.
· Cam kit with Comp Cams XM298H 254/264@.050, .585/.588, 112LC
· Aftermarket dizzy or recurved factory Dura Spark electronic distributor.
· Your Edelbrock intake with a Holley 850 #4781 mechanical secondary carburetor or single plane manifold w/Holley 950HP
Neighborhood of 550HP, a little less sith the smaller carb abd a little more with the bigger carb. Hydraulic lifters andmaintenance free. Pump gas premium.
The beauty of Build #5 is that if you choose to upgrade a season or two later, the shortblock and motor stay in the boat. Either do some max effort porting on the D3VE's or swap to TFS aluminum heads. The aluminum heads, with more cam and carb, could generate well over 700HP on Race Gas 110 octane or better.
Just some food for thought. Take it for what it cost ya.
ESA
