Mechanical vs hydralic lifters

[James H.]

My 62 340hp car came with solid lifters. The engine has been restored but I have no idea if its still configured the same way. Is there any way to visually tell if its still running on solids w/out going that deep into the block? or I've read that solids sound different when at idle.
Jim

[William C.]

Re: Mechanical vs hydralic lifters

Due to the clearance ramps used in the solid lifter configurstion thre is a noticable "Ticking" sound from the rocker cover area. It should speed up and slow down with the rpm of the engine. That is the external characteristic on the mechanical lifter cam. If the engine runs dead quiet in the rocker cover area, it has a hydraulic lifter cam installed.

[Wayne P.]

Re: Mechanical vs hydralic lifters

I agree It sounds like a good music . Some dislike the sound. I just had my
327 rebuilt put back 365 cam and solid lifters

[Duke W.]

Re: Mechanical vs hydralic lifters

Due to the clearance ramps used in the solid lifter configurstion thre is a noticable "Ticking" sound from the rocker cover area. It should speed up and slow down with the rpm of the engine. That is the external characteristic on the mechanical lifter cam. If the engine runs dead quiet in the rocker cover area, it has a hydraulic lifter cam installed.

Actually, if the clearance is adjusted so the valve is opened before the end of the constant velocity clearance ramp and closed on the closing clearance ramp, they should make little noise and might actually pass for hydraulic lifters. However, the Duntov cam is noisier than other OE mechanical lifter cams because of the harsh dynamics just above the tops of the clearance ramps and symmetrical lobe profile. Other OE mechanical lifter cams are asymmetrical, whichs close the valve more gently than it is opened and have milder dynamics on initial opening and final closing, so they are quieter.

The easiest way to determine lifter type is to remove the valve covers and check if any rockers are loose. If not, the lifters are hydraulic. If some are loose and the valve train is not excessively noisy, they are mechanical.

Then, if you actually MEASURE the clearances you might be able to ID the cam, and if it's an OE cam you will then know the proper setting clearances.

Duke

[Michael F.]

Re: Mechanical vs hydralic lifters

If it won't rev over 6 grand? It's a hydraulic. Better yet, if it revs freeely over 6 grand? It's a mechanical cam?

[Duke W.]

Re: Mechanical vs hydralic lifters

I know of a massaged 327/300 that pulls to 6800 and no one would ever know that it's anything but a box stock Flint-built 327/300. It idles butter smooth at 500 and has stump pulling off-idle torque.

Duke

[James H.]

Re: Mechanical vs hydralic lifters

Definately solids.. drove the car home tonight and it is rattling.. and has an agressive idle.

[Ralph A.]

Re: Mechanical vs hydralic lifters

I agree It sounds like a good music . Some dislike the sound. I just had my
327 rebuilt put back 365 cam and solid lifters

HI Wayne ? was that a 3030 cam you put back in your car or something else thanks Ralph