1982 Avanti



Q...Ken what was the ID on the one you used?  

A...Chuck,...CATCO 4111...A direct bolt in for GM "turkey plate 
pebble" converter and less than 1/2 the size.  About $90 (I got 
locally) Also available thru Summit (This is a high flow, high 
performance cat.)

Q...Corvette(ignition)wires and needed to be particularly long...

A...Chuck, don't know about Corvette. I use 8mm spiral core, radio 
supression, hi-temp wire with straight boot in order to get the wires 
away from the exhaust. I made my own wire lengths because I have a 
special Crossfire HEI cap that routes 4 spark wires from each side of 
the cap thus eliminating the typical HEI spaghetti mess.

Q...New cap, coil, rotor, elec. module (Accel)....

The stock GM coil produces 32 to 34K volts on a good day and runs out 
of poop at about 3600-3800 (when old & weak) to 4500 (when new).
 
I replaced the coil and module in "Ms. Pearl" with a Pertronix Flame 
Thrower Module and Coil--Summit PN's: PNX-D2000 & PNX-D3000, $40 ea. 
These carry the engine to valve float (4800-5000 rpm in a stock 
springs and cam 305).   

You may need a different Pin Count module since you still have the 
computer control and electronic advance.(I no longer have either. I 
converted to vac advance when I put on the Holley 600 cfm.) 
  
Holley makes both a 4 pin and 7 pin HEI module that my friends like. 
Summit PN's: HLY-891-101 and -102 $60  One of these will work. 

Regards,
Ken

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When I upgraded the coil, etc. I almost bought a new Summit Brand HEI 
(PN: SUM-850001R  $150) which comes with their 48,000 volt coil.  
This unit has vacuum advance, which I needed, but a friend had a 
vacuum advance HEI from a wrecked Z28 Camaro, free, so that is what I 
am using with the new coil, module and Crossfire Cap.

You might want to check with Summit to see if they have a similar 
unit to the SUM-850001R with electronic advance/computer plug.  The 
cost of new cap, rotor, coil, module could easily hit $150 and you 
would still have an old HEI - base,shaft,etc. (ie: Summit also has 
the 48,000 volt coil as a separate item. PN: SUM-850011  $37)  
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