How To Install Summit Headers
- Disconnect negative battery cable.
- Remove the exhaust manifolds. (6 bolts on each side)
- Remove the starter and clutch linkage if applicable.
- On 1975 Lemans remove the starter heat shield and throw away.
- Remove the oil filter from engine. you may want to replace it with an AC45 or Fram PH3429 for better clearance when done.)
- Remove shift linkage, steering lockout device, and chassis support rods on later models.
- Remove the center bolt from both engine mounts.
- Place jack with a wood block under engine oil pan and raise motor. Be sure to check for clearance while raising motor.
- Replace any worn out motor mounts.
- Slide in headers and start the bolts on the ends first.
- Cut slots in gasket to drop in onto the two bolts started.
- With header still loose put clutch linkage back in.
- Put in remaining header bolts, start with most difficult ones first.
- Tighten header bolts while "easing" header down.
- Lower engine down and check header clearance while aligning motor mounts up
- Reform lockout linkage and install.
- Install starter and oil filter, again the AC45/Fram PH3429 or equivalent allow more room to work with.
- Replace any lost fluids.
- Check around headers for proper clearance of fuel, transmission, brake lines, and etc.
- Bolt up reducers to exhaust pipes.
- Re-attach battery ground wire.
- After a couple of days to "break in" re-torque all bolts
- Header specs: they are four tube with 1/4" flange and on my 78 T/A with 255/60/15 BFG Comp T/A's the lowest point is 4-1/2" from the ground.
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