I presently have crane hyd. roller lifters. I am planing to swich to morel lifters. Will i need to change my pushrods. thanks.

when ever you change any part of the valve train, you should check the geometry and adjust as needed. Buy an adjustable pushrod set, and check them.

Make sure you double check the lifter bores on the Merlin block, Have heard horror stories of them coming out too tight and grabbing lifters. Another reason to buy Dart blocks....BBB

More than likely yes , do the magic marker trick after you think you have the right pushrods, and see if the roller in the rocker runs in the center of the valve tip. This is very important we don't want to side load a valve stem. BBB

Be VERY careful with a merlin 2 block/morel lifters and std base circle hyd roller cam. When I put my last combo together I used a merlin 2 block w/morel lifters. The oil holes on center band in the lifters were approx .020 higher than other hyd lifters which resulted in virtually no oil pressure at idle hot under 800rpm's.The chamfer on the lifter bore top hid the fact oil hole was partially exposed,I ended up reducing the base circle on the cam .060 which moved lifter down .030 which fixed the oil pressure issue,Smitty

Maybe that's the real story why the lifter bores would get scuffed. I won't have to ever experience this or all of the other shortcomings of those blocks because, I prefer Dart, or even a Bowtie. BBB

BBB,the oil feed hole height didn't cause the lifter to scuff,it just caused a vast amount of oil to bleed off at 700-800 rpm's idle. Howewver,the machine work on a merlin 2 block like mine has to be re-done OFTEN,my lifter bores were also tight along with cam tunnel being dimensionally wrong,mains being to tight when it came to bore size,etc. My block though was a blem,I spent more on it and strightening out the machine work than a prepped one would cost new but I'm leery of how good the "prepping" actually is because the blem on mine was 2 little spots of cast iron that had slight imperfections on the fuel pump boss and back edge where intake bottom had to seal. It seemed strange that ALL the machine work would be wrong TOO,Smitty

Thanks for the reply. I have crane lifters in now. I just though since I am changing the cam i would up grade the lifters. I know now that a dart block would of been a better choice but the person I had do the machining(Steve Schmidt in Indy)said we would go ahead and use it.Also it is a merlin III. thanks again.

Most merlin blocks can be considered blems unless re-worked and proven otherwise.... BBB

When Morel designed the retro fit hyd rollers for the GM engines they located the pushrod seat of the lifter to fit OEM pushrod length. The body of the lifter is .300" tall to work with the late model blocks and aftermarket blocks taller lifter bores. So the Morel lifter will work in early, late, or aftermarket blocks.

You should check your pushrod length to prevent premature wear.

Chris