I'm trying to install an effective evac system on a 468 BBC with about 14.5 to 1 compression for occasional street driving. I have a GZ vacuum pump on a similar engine which works great, but I hate to spend another $800+ if there is another way, being the cheap bastard that I am. I have never had much success with the standard evac systems, running hoses to the headers from the valve covers. Maybe I'm doing something wrong. Any suggestions? Thanks.