|MODIFYING THE||BOLT PATTERN|
Click on each picture to supersize
|Now it's time to fix the bolt pattern. The four
corner holes are correct, all the rest are wrong. I first filled all the
wrong holes with JB Weld, and sanded smooth when dry. Then I bought stock
standard V-8 gaskets to locate my new holes. I have 1986 and prior heads
so my middle two holes on each side will be on an angle. If you have '87+
heads your center two holes will be straight up. I hand drilled with no
guide, basically guessed at the angles. I had lots of filing to do when I
put the intake on the engine due to minor errors on the hole angles.
Marking and drilling the holes.
Finished, or so I thought. I had lots of filing to do for final fit. I used washers under the intake bolts to ensure a good grip.
Some of the holes are close to the plenum so allen head intake bolts were needed.
Look closer at these two center holes. I had to grind lots into the casting to get the bolts to start because of the angle of pre '87 heads. You late model guy/gals won't have this problem.