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PHASE 15: Motor Build Part 1

Now it was time to start on the motor for Madness.

I started with a '97 670 motor.  It has since be resleeved and bored to a 740.

I pressed out the sleeves myself by heating them in the oven for an hour at 350 degrees.  Then take them to the shop and tap them out with a brass drift and a hammer. 

Once that was done, I opened up the transfer ports to match the base gasket, and smoothed out the walls to eliminate turbulence.  I chose not to knife edge the leading edge as that tends to directionalize the air.  I use the reasoning that if you look at the leading edge of an airplane, it is larger and round.  This lets the pass over it and then tumble.  The speed of the air in relation to the bottom and the top is what gives it lift.  If you knife edge it, the air on side will tumble, while the air on the other actually directs away from it.  If you round the edge, both sides act the in the same manner.  I tested this theory with a heat gun and an incense stick.  The stick gave me a smoke trail to follow.

Then it was time to match the case to the base gasket.  As you can see by the machinists dye (Dykem layout dye) quite a bit of material had to be removed.  In some of the pictures you can also see that JB Weld was used on the sides of the Rotary Valve plate.  The transition to smooth out the turn requires going through the case at this point a portion.  JB Weld does the job of sealing it dependably.

These pictures show the layout and the before shots.     

CLICK PHASE 16 TO CONTINUE.

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