To all of you that are running big blocks in your blazers

[454 blazer]

Hi guys,as you may have read in my previous thread a few weeks ago , ive stripped a couple of lobes on my cam shaft. Were im at now is i put a 306 duration comp cam in and new lifters(stock gm ones) when i finnaly got it running , it run like a bag of s@@t.I adjusted the tappets took it for a run then adjusted them again , it seems like the are loosening them selves ive adjusted them over 10 times now and cant seem to get it right.My mechanic said that because i ran rotators on the intake valves as well as the exhuast valves the springs are weak??? is that true ? And do you have any recomendations on what cam , springs lifters and so on to put in.I think the 306 is way to big of a cam to be running in a heavy truck.Any feed back would be appreciated.BBs running 781 heads,750 double pumper , performer rpm intake , hooker headers.Thanks guys!

 

[sweetk30]

did you break in the new cam? if not then you have just ground out the new cam and time for a new one.

and if i recall most bbc cam swaps require new springs when cam is a few steps or more over swap as to coil bind.

hopefully 4x4high ( scott ) will chime in here sone.

and i think my self 305 cam is big . you need to look for a cam that has lots of bottom end power for our big heavy vehicles. you need tourqe to get the heavy pig going.