posted 07-28-2000 11:31 AM            

Dan Jones

Building a 414 STROKER Cleveland

The car is a daily driver and weekend warrior, so we had to establish a realistic goal.
This became: 500hp, pump gas, 6500rpm max, 6000rpm practical limit, low maintenance. In
fifth gear this is plenty fast. With 500hp it will get there fast too! As you will see
this is not a 'trick' engine. I built this to be as easy on the wallet as possible, yet
still meet the goal. Today 1hp per cubic inch is very easy to do, 2hp percubic inch is
up in the realm of drag race/Nascar, so our plan became a big inch 1.25hp per cube motor.
This is how (and why) we went about it.

351c all cast iron. 4.060 bore, 4.0 stroke, = 414cubic inches (x 1.25 = 500+ hp )
note: block is D2AE-CA used race block that already had thousands of miles at .045 over
without a problem. This is the only reason this block was not sonic checked. Except in
this case I would never bore a block this big, without a sonic check first. This was
honed with torque plates at Johns request to 4.062.

Crank is a production 400 'M' of unknown origin radically ground down from 2.311 on the
rods to 2.100 and from 3.000 mains to 2.750. Yes that is over .200 under, it is a source
of amusement when people worry about .020 or .030 under crank! This crank was supplied
as part of a kit purchased from a local speed shop, the snout, the counterweights, and
the oil passages were modified to work in the 351c block. As recieved (fully balanced)
I simply washed it and bolted it into the block with 110ftlbs and 45ftlbs. Rods furnished
with the kit are Eagle 6.000 small block Chevy (gets the expense down) I numbered them
washed them and installed them as is, torqued to 90ftlbs.

Pistons, also furnished with the kit are Ross, actual size 4.055 dia (.007 clearance from
4.062 bore). Deck height 1.190 this produces compression of just over 11 to 1, my intention
was to remove more material from the combustion chamber, bringing down the compression a
little, but Vegas was too close. The rings are 1/16 Speed Pro single moly, file fitted to
.016 end gap on the 1st ring and .012 on the 2nd ring. The oil ring is 3/16 standard
tension with a Ross supplied spacer/bridge as the wrist pin is in the oil ring groove.
Pin dia is .927 (small block chevy) with a .150 wall thickness and is 2.500 inches long. It
is secured with 2 spirolocks per side. I numbered them, washed them and installed them on
the rods adding the rings afterwards. The single valve relief (intake)is .312 deep at its
lowest point, piston to valve clearance is .16 as my hydraulic cam is fairly short on duration.

Bearings are H series small block Chevy, std rod bearings with no modifications, from Clevite
running .0025 clearance. Mains are std 351c .003 clearance, by ACL and are not full grooved due
to the crank being cross drilled by the supplier. Balancer is stock 4v/Cobra jet (used), Boss
351 or aftermarket would be a better choice. Flywheel is stock 351c. Oil system uses a
standard volume oil pump with a Motorsport or Moroso high pressure spring shimmed with a .060
washer for 100lbs pressure cold. It has 2 cover plates to reduce cover flex. Windage tray,
adjustable for stroke and rod combo's (clearance) from MPG head service in CO. Pan and pickup
are rare factory De-Tomaso race pan (10 quarts) as pictured in the official race parts catolog,
filter is Ford lf 1 hp, or Fram HP1 (due to the high pressure). No other oil system mods or
restrictions. Standard oil pump driveshaft, aftermarket is not necessary. Oil is Mobil 1
synthetic 15-50 wt no additives.

Timing chain is a used Cloyes true roller in good shape, the Ford Motorsport would be a good
choice. Cam bearings are stock Ford, they are installed undersize and then machined true.
Replacements are not as precise. Unless stockers are flaking I dont replace them. Cam, is a
custom regrind hydraulic non-roller. Specs @.050 are 242 intake,248 exhaust lift at cam is
0.351" int, 0.327" exh, actual valve lift with 1.8 rocker ratio is 0.63" int, 0.59" exh, lobe
center is 106 deg installed 4 deg advanced. Keep in mind that horesepower is only required to
6000 rpm so we dont need a top end cam but we do want a lot of torque to come out of corners
hard. Lifters are used re-faced stock Ford (mfd by Eaton), local cam grinder did lifter
refinishing for $1.00 apiece. Pushrods are Erson 3/8 hardened for guideplates. Boss 351 also
would work well for mild spring pressures.

Heads are 1970 351c 4v closed chamber, with hardened seats Erson stainless steel valves,
Boss intakes or single groove TRW intakes are ok but do not use stock exhaust valves or TRW
replacements. At these rpm's titanium is not necessary. These heads were modified by John
for screw in studs and guideplates, although the Crane econo conversion works with low spring
pressures (350 lbs max open). I ported the exhaust ports and bowls myself. Do not alter the
intake port or bowl in any way, this is counter productive, it doesnt matter how ugly the
intakes may look, you will only hurt them if you change them. Port plates on this engine
would be a waste of money, they alter the port incorrectly by removing the venturi or high
speed "neckdown" area needed to turn the mixture into the cylinder. The valve springs are 1.55
Erson singles, set at 125lbs closed and 350lbs open. the retainers are machined steel and
machined steel locks. P.C. seals are installed without the protective sleeve for a looser fit
on the valve stem (to promote valve guide lubrication). Head gaskets are Ford 'McCord'
D3ZX6051 AA Felpro 1013 are also good. I applied silicone sealer to the back edge of the gasket
to prevent water seepage. the head bolts are torqued in steps to 125ftlbs. The rockers are Erson
rollers at 1.8 to 1 ratio set at '0' lash plus half turn preload. Intake is a Holley Strip
Dominator, the best of the stock choices. This one had a lot of under carb work with a lot of
time on the flowbench. it was purchased used, from a friend. Carb is a Holley 850 double pumper
Ignition is a Duraspark distributor 34 deg total advance with a slow curve to avoid detonation
with our compression ratio. MSD 6AL box and coil w 6500rpm chip. Street plugs are motorcraft
AF32 raceplugs are AF501, gapped at .045. High flow aluminum water pump, Flow kooler or weiand.
Exhaust, john's custom, GTS headers from Hall Pantera, modified to remove the 'Y' collector
sections, and added a 2 1/8 step up, and large 4 into 1 collector, to a 3.0" pipe all the way
back with 2 supertrapp Mufflers( 3.0" cores removed for the track). From start to finish, I
spent 40 hours doing everything listed here, including the multi angle valve job and the port
work. It fired right up, John drove it to Vegas to break it in, and used it full tilt for the
first time at the PCNC track event. Could this motor be different...better...tricker...., sure!
but not simpler or cheaper!

footnote: On a Dyno Jet dyno, this motor installed in a Pantera, produced 432 horsepower(6200rpm)
and 400ftlbs torque (5100rpm) at the rear wheels.

posted 07-31-2000 02:36 PM            

However, I can't believe nobody else has any comments on building a stroked Cleveland. Come on guys, imagine those 4V heads feeding 400 ci instead of 351. Can you say Torque?!?

posted 08-01-2000 12:55 PM            

His old motor was a 377 Cleveland (offset ground 351C crank) with closed
chamber 4V heads, a Holley Strip Dominator intake, 750 Holley (flowed to
810 CFM), GTS pantera headers (Tri-Y design, 2" primaries, 2 1/4" collector),
2 1/4" intermediate pipes, GTS mufflers, and the same Isky cam. It dyno'd
at 370 HP at the rear wheels, sufficient to push his Pantera to 180+ mph
(averaged 165 mph over 92 miles at one of the Silver State open road races in
Nevada). A similar stroker with a bit more cam (solid flat tappet) recently
pulled over 450 HP at the crank with a dual plane Blue Thunder intake. Another
made 472 HP with a Crower hdraulic flat tappet cam. The difference with the
smaller strokers is they require more rpm to make the power and don't have
as much torque down low.