<VV> Pinging turbo

[Sethracer at aol.com]

dave.thompson at verizon.net asks for advice:

I tried  several more times and always got pinging above
zero. I'm running 91 octane  from a busy gas station so I know the fuel is
fresh. I have never gotten  any pinging below zero boost. In my water-cooed
days, pinging was caused by  poor timing (in most cases).



>From Seth - If it is pinging, it is probably still timing caused (along  with 
the 91 Octane Gas - Turbos would like better octane - but it is not  
generally available in California)
 



In my research I have learned that the turbo distributor has a  pressure
retard. I looked up the part number and that's what I have, not  vacuum
advance. The hose to the intake is new and tight (should there be  clamps on
the hose?). I have the Pertronix Ignighter II and a new 0.6 ohm  Flamethrower
II coil (no resister per instructions), new cap, rotor, plugs  and wires.
Before the rebuild I could hardly get 3000 RPM so I have nothing  to compare
it to.



So, is your distributor stamped with 1110329 on the side of the housing -  
that is the 65-66 Turbo distributor. (I am not sure of the 1964 Turbo Dist  
P/N). The pressure retard is easy to ID, since only the Retard units have  the 
nipple "ridge" to retain the hose. And, yes, there should be clamps on both  ends 
of the hose. Is the hose correctly attached to the base on the right hand  
cylinder head? 
 



With this info, I have a few questions:



Am I  right about the timing being the culprit? If not, what else should  I
check?



If the distributor is not originally a turbo dist, the mechanical advance  
curve would be wrong for a turbo. The turbo initial advance timing is set at 24  
degrees BTC. No mechanical advance should come in until some high RPM number, 
 like 2500 RPM. The Standard (non-turbo) distributors start advance at 1500 
RPM  or even less. With 24 degrees of initial advance, you don't need that  
advance. 
 



What is an easy way to test the pressure advance without  purchasing
expensive tools? I don't want to purchase a new one only to find  that the
one I have works.



If you have an air tank for your tires, you can gently apply air to the  
retard - using some duct tape to seal the hose to the retard. Again, be gentle,  
high pressure can kill the diaphragm inside the unit. It should move to the 
stop  pretty quickly.
 



Could I be having other distributor  problems?



See above.



I had one guy say that turbos shouldn't use the Pertronix  electronic
ignition. I should only use points. What are your  opinions?




BS alert! There is no performance downside to the Pertronix unit. 
 


My  buddy asked if the sound is not pinging but is the turbo spooling up. It
is  a rhythmic or ticking sound. (I thought turbos had a  whine)



A pinging motor will be accompanied with a loss of power. I have never  
mistaken the sound of pinging to be a turbo spooling up. The ticking sound  could, 
of course, be something else - like an exhaust leak - very common on  turbos. 
Check every bit of the exhaust system ahead of the turbo.



Any input on this will be greatly  appreciated.



I hope you find it. Let us know which P/N distributor you have. -  Seth



Thanks,



Dave Thompson

63 convertible  Spyder (clone with a 64 drive train)

Westminster,  Ca







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