Popping sound in exhaust

[AJ/FormS]

nice work;
but that 6.5PV has got to go. It forces the mains to do all the work, which then have to be bigger than necessary to cover the hole that occurs when the correctly sized mjs would have run out of fuel.
After you put a 10.5 in there you will be able to downsize the mjs at least two, maybe 4, numbers. and this will clean up your Part-Throttle city driving, and the engine will be much more tractable, pulling harder,sooner, with less throttle. You won't even miss the timing you took out.
All that with just a PV swap? Well, that has been the experience of many guys here,me included; when the MJs were too fat to start with. Which they often, perhaps usually, are,on and engine that pulls 14" at 750 rpm.
on a different note; in the end you may have to re-phase your rotor.

 

[yellow rose]

nice work;
but that 6.5PV has got to go. It forces the mains to do all the work, which then have to be bigger than necessary to cover the hole that occurs when the correctly sized mjs would have run out of fuel.
After you put a 10.5 in there you will be able to downsize the mjs at least two, maybe 4, numbers. and this will clean up your Part-Throttle city driving, and the engine will be much more tractable, pulling harder,sooner, with less throttle. You won't even miss the timing you took out.
All that with just a PV swap? Well, that has been the experience of many guys here,me included; when the MJs were too fat to start with. Which they often, perhaps usually, are,on and engine that pulls 14" at 750 rpm.
In the end you may have to re-phase your rotor.

And if he could buy one, he'd probably be better off of a 12.5 power valve. If he has that much idle vacuum his cruise vacuum has to be through the roof.