Let's start a new RHS head thread . Pushrods?

[dusterdoug]

I have an adjustable pushrod on the way to check after the new rockers get here, (did I mention Iron rockers won't work with the beehive retainer? #-o )
But I'm a wonderin' how much longer that OEM are your pushrods are Brian, Maddart, anyone else...??

Thanks

 

[340sFastback]

I had to go with shorter then stock push rods because of the taller hydraulic roller lifters. But the small base circle cam, milled heads, and decked block had an impact on push rod length too. You really have to mock it up and measure because there are so many variables from one engine to the next.

 

[pettybludart]

Get your pushrods last.

 

[Brian Hafliger]

I have an adjustable pushrod on the way to check after the new rockers get here, (did I mention Iron rockers won't work with the beehive retainer? #-o )
But I'm a wonderin' how much longer that OEM are your pushrods are Brian, Maddart, anyone else...??

Thanks

I'll check that tomorrow, I have some 273 rockers I can mock up on the head with the spring and retainer.
I'd be surprised if it didn't because the beehive retainer is tiny compared to an oem spring/retainer combo.
I use small base circle cams, milled heads and block, different rockers...pushrod's are done during mock up only when I have all the parts I'm using.
I use 3/8 Manton pushrods with oil holes in them and highly recommend running oil in them.
Brian

 

[dusterdoug]

Yea, pushrods are going to be last after the new rockers get here. I was just curious, is all.

The issue with the iron rockers (Isky 1.5) is all about the size of the rocker pad and the tip of the stem only being about .020 higher than the retainer. During a sweep of the rocker travel (using .028 lash with the old cam in place) there is only .015 worth of clearance between the edges of the rocker pad and the retainer. Based on the cam that's going to be run, it has .018 lash so there goes any clearance. Comp stainless rockers were shipped today...

But in mocking the motor up using the 7.555" length pushods that were run with the previous X heads, I nearly ran out of thread when trying to get that .028 lash. Then I measured a pushrod tunnel on the OEM X head and the RHS, and what do ya know? It's taller!

Brian, you da man! I always appreciate you edumacting us small block knuckleheads!

 

[moper]

I have Iskys on the build I'm finishing. They were close on the std LA spring, but I basically removed the casting surface features and they cleared no problem. I can't imagine if you narrowed the contact pad you would weaken them. Just go slowly and don't get them hot enough to discolor. The retainer doesnt move in terms of left or right or oscillate up upr down. It does rotate, so I'd keep something like .015-.020 clearance and you should be fine using them. I use Smith Bros 5/16 pushrods and with the hydraulic roller lifter they are the shortest I've ever ordered...lol.