[Shockwave78]

Originally Posted by 78w72

Agree with making the rockers adjustable, ideal way is to get BBC 7/16 studs... but for a smaller cam like that you can just buy some SBC crimped locking nuts and set them according to the sbc procedure in most manuals or do the individual lobe on base circle procedure. doing this will be much less cost & is a quick easy way to go to adjustable to see if the stock 20lb/ft setting is the problem. the final adjustment is based on the lifters used, some want 1/2-1 full turn after zero lash but some want 1/4 turn, follow what the lifter manufacturer says to use.

I have a comp xe268 cam in my 78 w72 that runs excellent for 13+ years using the stock rocker studs & crimped nuts, has more lift than yours at .477.

Thanks, ill give the crimped nuts a shot

[78w72]

Originally Posted by Shockwave78

Thanks, ill give the crimped nuts a shot

Just be sure you do the adjustment right based on what the lifters instructions say, crimped nuts are only good for 2-3 times adjusting, 1 time is ideal. Can buy them at most local auto parts stores, just say you need rocker nuts for a 1978 350 chevy.

Heres a link to show how it can be done on smaller cams... for bigger cams its best to do when the cam is on the base circle for each valve.

https://www.pontiacstreetperformance...p/rockers.html

[Gach]

Originally Posted by Shockwave78

Would the stock valvetrain cause the valves to hang open/not close all the way?

Lets say that cam was ground on a 108, you installed it dot to dot. per instructions. But never degree it, now for some reason (gear set ) being off, you check it ( degree it in ). And it comes in at 114 thats severely retarded. So now its not filling the cylinders hence the low compression reading. No matter what aftermarket cam it is, you just can’t take for granted that its actually on a 108. Also it may not be the case, the cam is off, but it could be timing gear set itself, thats why the offer timing gear sets with 9 key ways. Hoping now you understand why ever cam should be degree and checked to make sure. This would now eliminate the cause of that being the power lost. Then you could move on to valve adjustment valve train being problem. I mean you did a could job on checking all the obvious things.

[Gach]

Moving onto valve adjustment, usually once valve is close ( with hyd lifters) you take up the slack, by turning push rod until there’s no slack, then go 1/4 or 1/2 turn what ever they recommend. It’s been a while since I’ve done hydraulic lifters so thats my vague memory. Its kind of hard to mess that up, only thing that could is if, even though you thought valve was completely closed, may not have been. So that would hold valve open, partially. Could happen on either intake or exhaust, so thats why I take the time to go though them again, just to check.

The other thing, with hyd lifters what I used to do, was put the lifter in a can of oil and pump it up. Because i’ve found that some times, if the lifter wasn’t pump up, now your adjusting it, taking up the push rod slack up, but it’s actually already depressing the plunger. Now you fire it off the lifter pumps up. But the valve isn’t completely closeing. But anyway definitely going with the studs and adjustable nuts is a plus, just assures a more solid adjustment