I'll throw a little different slant out there. I have never had any of the problems described above using manifold vacuum advance on any of my vehicles. Current stock 8.2:1 78 400 likes the extra 20 segrees the dashpot adds, no pinging when cruising. Been trying to get the HC down on it without cats so I've no been running any. With the additional advance the car idles with less throttle blade opening on carb and pulls more " vacuum also.Playing with dashpots is something you can do to limit total also.
I used to race in the old NMCA stock classes and they factor your HP based on how much vacuum the car pulled @1000rpm. The Buick nationals also rquire a certain vacuum at 1000 or 1200. That limits the size of the cam. EVERYONE, even the 10 sec BBC Camaros ran full manifold vacuum advance to help big cams pull more " at idle.Often they also had almost all the mechanical advance in by 1200 also.
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1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever!
1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand
1965 GTO 4 barrel 3 speed project
2004 GTO Pulse Red stock motor computer tune [email protected]
1964 Impala SS 409/470ci 600 HP stroker project
1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs
1964 Corvette Coupe 327 4 speed
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