an exhaust leak will be audible in drive as well as neutral correct? If in drive, the exhaust leak becomes louder as i accelerate, when i switch to neutral and rev the engine to the same rpms, the sound should be there as well right? does it become louder in drive because the engine is under load?

_________________
70 Plymouth Valiant 4dr

Where are you thinking you have a leak?

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

I hear a tick tick sound while accelerating, sometimes it goes away as the car warms up. The tick sound reminds me of a cracked manifold I had once. I double torqued the bolts, checked for leaks. noise still there. No changes to engine. Sound just appeared one day. Manifold to head?

_________________
70 Plymouth Valiant 4dr

Could be valves?

Are you sure the manifold isn't cracked?

Sound going away after warm up sounds like a crack to me (heat expansion seals the leak)

Or a header pipe crack/leak

_________________
Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

A little bit of trans fluid down the carb should smoke out the crack? The heat expansion makes sense. I just wonder why only in drive?

_________________
70 Plymouth Valiant 4dr

There's more exhaust flow and backpressure in drive.........

_________________
Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

the leak has progressively gotten worse. it's coming from the back exhaust runner. it is very loud and very noticeable. i gooped it as a temporary fix. as this is my daily driver i figure i'd purchase another head to do the work on. that way i can get the swap done in one day. going to pick up a head from board member kielbasa next tuesday. plan to do some port matching and a little polish. getting the engnbldr valves, and cutting the head a bit. i figure if i'm pulling the manifold off to put a new gasket on, i might as well pull the head, i'm already halfway there

_________________
70 Plymouth Valiant 4dr