RoadRocketZ28

Hello everyone,
I discovered while rebuilding my SBC 350 upon priming the hyd. lifters that some are a little different but same part number.

The difference is being able to push down on the plunger with the pushrod. Some are very very easy to push down and some are not at all easy to push down. I have noticed a slight difference in the machining of the lifter as well. Some have some sort of machined groove around the lifter base about 3/16 inch up and others are smooth. This ridge or groove is machined into the lifter as I have 12 of them this way and 4 that are smooth. (not sure if this is a good description).

The main thing is the ease of pushing the plunger down on some and others hardly move.

Has anyone encountered this before or know what this is?

Any and all help is greatly appreciated as this puts a hold on the buildup I am doing. If all else fails I can drive to Summit Racing, but would like to avoid this if I can.

Thanks,
Aaron

RoadRocketZ28

Well, I have found some answers to this but still unsure which ones to use for my street buildup. (late night research)

The lifters that have very limited plunger travel apparently have some type of retainer inside that limits the travel of the plunger making act like a sold lifter but without the constant adjusting you have to perform. These are for high RPM camshafts, (according to the description from Scoggin-Dickey's website.)

http://www.sdparts.com/product/HT-81...licLifter.aspx

I am thinking this allows for the higher RPM without the valve float due to slow bleeddown of stock lifters.

Does anyone have any more info on this?

Thanks.

OldSStroker

You are probably on the right track. At the very least have all 16 lifters the same. In order for someone to recommend which lifter to use, they would have to know the engine combination. If it's a stock rebuild for crusin' I'd go with a stock replacement lifter.