Anyone know if a custom pushrod length is required for Merlin iron oval port BBC heads? Do they use +.100 valves? Thanks in advance!

I've got the cast-iron Merlin oval ports on my 468. My engine builder had to make custom length pushrods. It's been a few years, but I think they were 8.450" for the intake and 9.550" for the exhaust. That is with stock stamped rocker arms if it matters.

Looks like I need to go +.150 on the intake and +.250 on the exhaust--pretty close! Thanks for the help.

ask BB_Mike....he too is running Merlin Ovals graemlins/thumbsup.gif

Call up World Products.

I put mine together with stock push rods. I had the heads angle milled, so that measurement should have stayed that same as if it where off the shelf.

I do use Harland roller rockers. Lash has never been a problem. I pulled the 2.19/1.88 valves out of my old 049 heads and dropped them right in.

Don't rely on some internet for YOUR motor. call the people that designed the parts. graemlins/waving.gif

Thanks guys. What I meant is I actually used an adjustable pushrod and got those numbers from the wear pattern on the valve tip. Too much $ invested to get Internet advice. smile.gif

Mike, that's cool you were able to use stock pushrods. On my motor, the rocker tip was all but falling off the exhaust valve. Intake wasn't as bad but still needed more length.

I'm using a solid lifter cam so I think the plunger in the lifter body is set deeper than a hyd.

I called W/P's before I bought my Merlin ovals years ago and they said the Merlins worked with ALL stock valve-train parts!!!

I asked specifically b/c of worrying about buying stuff I didn't know about at the time...

pdq67