AKA Holley Street Dominator. The “Z” series is easily identifiable by the “9th” runner at the rear of the intake to connect cylinders 7&8 to help balance the engines air & fuel intake charge.
It’s a low level single plane intake that lost power vs other dual plane intakes in the same arena of performance it was listed and touted for. It will out HP up top in the rpm range vs the dual planes.
I would not use this intake for mileage purposes.
Now that Edelbrock SP2P was well liked for its mileage gains. For ease, ether a factory 4bbl or a Edelbrock performer will do well and there easy to get.
@Bewy While I normally agree with the MSD statement, he is ditching the lean burn system. It’s not a bad ignition replacement idea. The trick here (U.S.) is finding a vendor that has the OE style ignition box that will last AND provide a nicely upgraded spark.
So far, IMO, FBO is the best bet.
(4secondsflat.com)
If you loose mileage with headers, there’s a problem, and I don’t think it’s the headers!