Just thought i would pass on some info on a bull dog headed engine we are just finishing up. There are some interesting thing s to note on these heads. First, they come with 1.55 diameter springs, which really opens up our selection for springs when we do the more radical cam set-ups on these engines. With the valves being longer aswell, going to higher lift is no longer a problem, as it is with the stock type head configuration. The rocker arm pedestals have also been moved to give a better pushrod to rocker arm geometry, and also has eliminated any interference between the bigger springs and rockers. There has always been an issue with trying to run 1.55 springs and roller rockers, the rocker body rubs the spring or spring reatainer, not so with these heads. The other problem we have had in the past, especially when you sart trying to run bigger rocker ratios, like 1.65, is that the pushrods tend to get pushed against the pushrod hole in the head, this tends to try to kick the pushrod out of the lifter cup, not a good thing. We now have a much closer to 90 degree angle from the pushrod to the rocker arm, this will allow the rocker to operate in a more natural range. These heads require different length pushrods than stock, but this is not an issue as most, if not all performance 455's are not going to use the stock pushrods anyway, and most are not going to use stock length either. By the time you deck blocks, mill heads, run smaller base circle cams and whatever, it all adds up to non stock pushrod lengths anyway. Jim Burek P.A.E ENTERPRISES
Mike Stark of Creative Flow Management, posted on his board that these heads ported have gone over 400cfm, along with some info on all the other heads by Bulldog. ----------------- 67 camaro 3300lbs, pump-gas 502, hyd. roller, 049 oval-port, 10"ATI, 373s, ET streets, slapper bars, w/mufflers. 1.44, 10.08@132.76 http://www.cardomain.com/id/67rs502
