the thing that makes me think the leaks may be a problem is when I give the eng gas there comes a certain point in the higher revs in 1st and 2nd gear where it seems like the rpms are hanging up without the eng power going up in tandem...maybe the mix gets too lean at high revs from the leaking? I thought about timing too but my throttle response is really good from an idle if you rev it abruptly and it idles incredibly smooth...I replaced the head a little while back which seemed to make it run a lot better...
you know you can audibly hear that carb sucking to beat the band when you gun it going down the road and it's sound strikes me that the motor is not being allowed to breathe near what it would like to...sounds like it's trying to suck up a tornado thru a straw... it has a small chrome air filter about maybe six inches across or so can't see that being all that much of a constriction...some of those twin carb set ups could be something to consider maybe...but since I am still trying to sell this truck I'd just like to have it running as good as poss without putting much $ into it...