EVO Stroker Buildup
Here’s a little pictorial on putting together an
Evolution race motor. In this article we’ll highlight some of the
differences between the newest generation 4G63 and the early 4G63 motors.
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| Here is one of our stage 3 Evolution engine blocks. This
particular model is a stroker. We enlarged the bore to
3.366” and added 12mm more stroke to get roughly 2.3L of
displacement.
Notice the proprietary Magnus pistons with the quench
pad technology. These pistons are specifically designed
for the Evolution engine, using experience we gained from
working with the earlier 4G63 engines. The quench pad
provides greater resistance to detonation and is basically
an imprint of the head transferred to the piston. Why do
we do this you ask? This helps squeeze all the gasses into
a smaller space, making the combustion chamber smaller and
more efficient.
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| Here is the Evolution 4G63 head, very similar to the old
style head in casting but has a few major changes. First
off we all know the flow is reversed. That won’t make
any major changes to performance though. The injector
bosses are now in the intake manifold instead of in the
cylinder head. Placing the injectors a bit further back
will give better atomization and also a bit more power.
Although the 5 to 10 mm of distance that it has been moved
to, to be able to get a measurable power gain would be
splitting hairs… but it is an improvement nonetheless.
The intake ports have now been made a more normal size.
The 1G port was always in our opinion too large to get
good low end velocity out of. This head is much more of an
improvement over the 1G DSM. The port entry angle is only
10 degrees; whereas the 2G DSM head had a much steeper
entry angle, which was better for performance. A lot of
manufacturers are getting away from steep angle intake
ports which we can only guess for two reasons. A) Low hood
line and less complexity for intake manifold castings or
B) Emissions. Sharper angles will promote more tumbling
and better atomization, aiding in emissions controls.
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| This picture shows finished intake ports displaying the
10 degree entry angle. |
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| Here we see a finished Evo port up against a 1G DSM
intake manifold flange for comparison. That’s a huge
difference! |
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| Here's a finished EVO port and how it matches up against
our CNC machined intake manifold flange. This image also
visually shows the injector bosses. |
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| The exhaust port is almost identical to the original
4G63 engine. Very little has changed except the bolt
pattern which didn’t even change that much, its just
reversed. |
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| Here we take the Stage 3 Head and sit it down on the
Stage 3 block. Now comes the task of checking clearances
and degreeing the camshafts. We wanted this motor to run a
9:1 compression ratio so we opted for a .030" gasket.
Had we wanted to try 8.5:1 compression ratio, we would
have installed our .060" gasket. |
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After the piston clearances have been checked (our
pistons allow high lift cams to be used without
interference problems) we dry assemble the Timing belt
pulleys and idlers temporarily so we can make degree in
the cams, making sure they are installed at the
manufacturers specs. This not only ensures that the engine
will run properly and make power where it is supposed to,
but it also ensures that you won’t have any clearance
issues between the valves and pistons if your block and
head have been decked a few times.
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| Now that we are sure the camshafts are degreed and
installed correctly, we checked for valve clearance and it
was more than adequate. Now it’s time to begin buttoning
up the motor. The timing belt pulley are removed and the
gasket is installed on the oil pump housing. The air
separator baffle is installed (Very important do not omit
this item, this prevents the oil pump from picking up air
bubbles instead of straight oil) along with the oil pick
up tube. We use a light coat of sealant on both sides of
the front cover gasket, but always install the pickup
gasket dry, so as not allow any sealant to get into the
oil pump where it could instantly destroy the motor. |
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| The oil pan is installed and the rest of the timing belt
accessories are put back on for good this time, including
the crank sensor. Notice our custom balance shaft
eliminator plug. They are machined from 6061 aluminum in
house. We use this instead of the mitsubishi rubber plug
because the rubber plug has a tendency to fall out and
cause a gargantuan oil leak... at the most inopportune
moments. Now that we no longer have balance shafts
installed, this means the oil pump orientation when
setting the belt is no longer critical. What’s different
on the new 4G63 is the timing markings. You must have the
rocker cover on to set the timing belt. Why? Because the
rocker cover has the cam gear timing marks on it. |
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| There it is all installed, belt on and ready to go, but
wait theres something missing. |
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Theres the Magnus EV0 8 stage 3 2.3 Stroker Motor with a sexy Intake
Manifold attached to it. Now it’s ready to go with.. extra torque and
horsepower! |
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