<VV> Pinging turbo

Harry Yarnell hyarnell1 at earthlink.net
Tue Apr 8 08:50:19 EDT 2008


Reply in message.

harry yarnell
Poohbah of Perryman
perryman garage and orphanage
hyarnell1 at earthlink.net
----- Original Message ----- 
From: "Dave Thompson" <dave.thompson at verizon.net>
To: <virtualvairs at corvair.org>
Sent: Monday, April 07, 2008 9:32 PM
Subject: <VV> Pinging turbo


> Hi Guys,
>
>
>
> Well, I just passed 500 miles on my new engine and after changing the oil 
> &
> filter, I started to get a little more aggressive in my driving. When
> getting onto the freeway, I GENTLY ran it up to 3500 to 4000 RPM. As soon 
> as
> the boost gauge hit zero and above the engine started to ping. I 
> immediately
> let off the peddle. 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).
>
>
>
> 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.
>
>
>
> With this info, I have a few questions:
>
>
>
> Am I right about the timing being the culprit? If not, what else should I
> check?

Welcome to turbo boost. With today's fuel, even the retard isn't enough. The 
turbo was designed for higher octane that's not available anymore.
>
>
>
> 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.
>
>
>
> Could I be having other distributor problems?

Probably not. Apply a few pounds of shop air to the retard unit to see if 
it's working.
>
>
>
> I had one guy say that turbos shouldn't use the Pertronix electronic
> ignition. I should only use points. What are your opinions?

ABSOLUTELY use the Pertronics; gives a much hotter spark when boost comes 
on.
>
>
>
> 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)

Ticking? Havn't heard that. Whine maybe; if you can hear it over the roar of 
the engine.
>
>
>
> Any input on this will be greatly appreciated.
>
>
>
> Thanks,
>
>
>
> Dave Thompson
>
> 63 convertible Spyder (clone with a 64 drive train)
>
> Westminster, Ca
>
>
>
>
>
> _______________________________________________
> This message was sent by the VirtualVairs mailing list, all copyrights are 
> the property
> of the writer, please attribute properly. For help, 
> mailto:vv-help at corvair.org
> This list sponsored by the Corvair Society of America, 
> http://www.corvair.org/
> Post messages to: VirtualVairs at corvair.org
> Change your options: 
> http://www.vv.corvair.org/mailman/options/virtualvairs
> _______________________________________________
> 



More information about the VirtualVairs mailing list