383cid, 390HP @5100rpm
431 lb,ft torque @4500
Operating range WOT 4700-5100rpm
The Benefits of our Offshore       
383ci. over a 350ci.
"More Torque"
1) More torque = faster planing time
2) Higher cruise speed. In the 3200-3800rpm
cruise range, your boat will have a higher
cruise speed, due to the fact you will be
running a higher pitch prop.
More pitch/same rpm = more speed.
3) Higher top speed.
4) More pulling power for skiers or
heavily loaded boats.
Torque is what is important in a marine engine,
NOT horse power. You want more TQ. than HP.
A 200hp boat with 400ft. lb. of TQ.
will be faster & more efficient  than the same
boat with 500hp and only 350ft. lb. of TQ.!!
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The Benefits of our "OFFSHORE 420" over any  350ci. - 454ci.   
"More Torque"

1) More torque = faster planing time

2) More torque = Higher cruise speed.
In the same cruise rpm range you were before, your boat will have a higher cruise speed.
Due to the fact you will be running a higher pitch prop at the same RPM. More pitch/same
rpm = more speed.

3) More torque/HP and less weigh = Higher top speed.

4) More torque = More pulling power for skiers or heavy loads

5) Through the extensive use of high strength, light weight alloys,
these engines weigh only 547lbs!
( 200lbs lighter than most other small blocks, 350-500lbs less than most big blocks)

6) Each engine, Hand built to "exacting" tolerances, for years of
trouble free service.

All engines come with certified, serial numbered  dyno sheets.
These light weight powerful Blueprinted engines are designed for sport boats, runabouts,
ski boats
, cruisers,or sportfish that desire more in the performance department, but may not
have the room to handle a big-block's larger size or weight. Smaller and lighter than
displacement big blocks and most small blocks, the
OFFSHORE 420 actually provides
comparable performance to the 496 Mag , their compact size and high power-to-weight ratio
make them an
extremely versatile engine.
The low maintenance
Offshore 420 is the power of choice.

Estimated prop shaft HP w/free flowing exhaust, 390hp. Carb.
Although these engines are a few ft-lbs of torque less than a 496
(+/-20lbs), they more than make up for it with their
lighter weight, and higher horse power!

Specifications may change with out notice, due to constant testing and improvements being made.
These engines require no more maintenance than any other marine engine.
(oil change every 50 hrs, full tune up 500hrs)
We carry and build, 383 marine engine,rebuilt
boat engines, new boat engines, marine diesel
engines,,mercruiser 383,mercruiser engines.
We also carry crusader marine engines.383
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engines, marine diesel engines,mercruiser 496
mag ho engines,377 ci marine engines.
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engines,crusader engines,496 mag,mercruiser 496 mag,496 HO.
More power than any mercruiser 383.our 377 6.2L Will run circles
around a mercruiser 383. Forget the mercruiser 383! The rebuilt
mercruiser marine 383,performance marine engines marine
383,performance marine engines marine 383,performance marine
engine mercruiser 383 is just that mercruiser rebuilt 383,
"REBUILT"! marine 383,performance marine engines
2 Year limited warranty
New GM performance stroker block (ZZ4 4 bolt main)
New forged steel crank (one piece rear main)
New Bushed forged steel rods   
New forged pistons
(9.2:1 floating pin)
New Custom grind HYD. Roller cam Vmax lifters
AFR ELIMINATOR 195 heads 2.02 int. 1.60ex.
(inconel exhaust valves)
New Manley push rods
New Performer air gap intake.
(carb. model)
New 750 cfm Marine Carb. (or 1000 cfm MPI option)
New marine elec. fuel pump
New flywheel and damper
(14"with double bolt pattern)
New Stainless steel roller rockers
New Stainless steel fasteners
New custom engine cowling
New Delco EST Marine HEI. System
(rev.limit 5500)
New engine hour meter
New accusync system for twin engines
New oil coolers
These smooth idling (650rpm), BULLET PROOF engines are designed as direct replacement marine engines.
(MerCruiser, Crusader,Volvo, etc.)
Inboard or Inboard/outboard
They run on  dock side fuel. (87octane) 9.2:1 comp. ratio
WOT rpm 4900-5300
Bob Tail

BW 72C  1.1

ZF 63-A  1.25

MPI 1000cfm
see note**

3" taller risers
$ 15,899.99




Standard features include
We do not recommend using this
engine with alpha drives,
we have run similar engines
on smaller, light weight boats
(20' / 2000lbs) through
the alpha drive , with good results.
100% NEW, dyno tested, broken in and
ready to be pressed into service!
* Setup for bravo or alpha, drive not
included .
Engine, 2 Year limited warranty, 5 year exhaust!
New starter (high torque reduction gear)
New alt. (78 amp)
New freshwater cooling
New motor mts. (application specific)
New ARP bolts & studs
New high pressure /volume oil pump
New cast aluminum 8qt. Oil pan
New remote oil filter and cooler
one piece Stainless steel
header manifold (5 year warranty)
New quick drain oil (I/O only)
Standard 9 pin wiring harness w/hr meter
(canon plug)
Epoxy paint with chip resistant hard coat clear
Low oil pressure shut down, high temp alarm.
New "insta-start" starting system
(instant start ups in any weather)
Custom paint colors $190.00 (see chart)
"E3" Spark Plugs
All 420's now come with one piece SS header/manifolds
420 MPI Click image
Add $300.00
See our 1000hr. program for OFFSHORE 420 owners.
**There is a slight  HP gain with the
1000cfm MPI system
EFI engines come with diagnostic
software and cable.
420's with hurth 63A's 2.57:1 crusader 454 replacements
When you look at all the standard features of the low maintenance 420.
Such as  the high power to weight ratio, ease of repair, off the shelf parts availability, and
unsurpassed performance. You'll see what a great bargain this package is.
Compare the power,  weight,  standard features and nothing else even comes close!
All engines now come with
Stainless header manifolds
Offshore 320 merc replacement (alpha drive)
The only 400+ HP small block engine on the market capable of running thru the prop exhaust without reversion problems.
Total dry weight of a complete
offshore 420 MPI.
(carb. Slightly less)

350 marine engine = 730lbs

454 marine engine =

496 Marine engine =

(350, 454  and 496 weights are based on
manufactures published weights, engine only)
420 MPI, 437hp The most powerful direct replacement engine on the market!
Layaway payment plans are Available.