[stevesch]

How can i tell if i have mechanical lifters or hydraulic lifters on my engine? It is a 1972 chevy 350 4 bolt main. The engine came out of a camero.


Thanks,
Steve

[302 Z28]

Chances are that they are hydraulic, unless your engine was the high performance LT1 350. Mechanical lifters are very noisy. If you already have access to the lifters you can simply press down on the pushrod seat of the lifter. If it moves they are hydraulic. If it doesn't move it's mechanical unless it's stuck.

Vince

[stevesch]

Thanks Vince!!!


The casting no. on my block is 3970010 from years 68-76. A book i have says they were in trucks and high performance applications (4-bolt mains). So you would belive it has hydraulic lifters then?

Thanks

Steve

[woodz428]

The majority were hydraulic lifters, so unless it is the LT-1 or someone changed the cam, it is probably hydraulics.

[stevesch]

Thanks woodz428!!!

cool..........also the heads on this engine are cast # 330645 big valve so would you call this a high performance engine? Also would you adjust the valves with it running? I have one that is really taping.


Thanks,
steve

[crazy larry]

SURE YOU can if you dont mind oil all over the place, or you could take an old trashed pair of valve covers,cut the tops out to control some of the oil..... someone makes clips you can put on the rocker to deflect the oil, but thats $$$.......

[RedRocket]

Only some of the 3970010 blocks have 4-bolt mains.

[302 Z28]

And big valves do not necessarily mean high performance. It is typical to see 1.98" intake valves in small block Chevy smog heads of enormous volume.

Your welcome
Vince

[stevesch]

Thanks guys for your help!!!!!!!