[HWYSTR455]

The '77 L78 used the 278/298 cam, and with 1.5s, lift is .364/.405 . A simple change to 1.65s would almost be like a cam change, but you need to enlarge the pushrod hole in 6x4s.

I've seen folks do that with heads on the car, but if I personally were to try it, I would pull the intake and valley pan, so there's a straight shot to clean up. If you go to that trouble, might as well change the cam.

As I recall, stock heads can support lift up to about .469 before there's issues. Then there's problems with not only the pushrod, but the rocker to retainer clearance too.

The L78 was a 200hp version, and with a little tuning, think you could prob get another 20-30 out of it. If you wanted a little more, than step up to the 1.65s. I prob wouldn't put too much effort into that engine and just save for the new.

If by chance you were still thinking of a cam, since it's a low compression engine, choose one with short seat timing, to help dynamic CR.

If you want to do the cam, and you need to go through the heads, you would be better off getting a set of already done heads of the 72cc variety. That would bump the SCR, you would have a better cam selection, but then you will start testing the strength of the 557 blocks.

And there starts your domino effect....

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