[68hotbird]

I am assembling a high port stock block engine Combo. It has a .440 lobe solid roller cam trend 10.300 length tapered end 3/8 pushrods and standard valves. I have 3 different rocker arms (Harland sharp, scorpion, and comp Red) none will clear the pushrod below the seat without a fairly significant amount of grinding. Just curious if this is fairly common with standard rocker high ports. Thanks for any info.

[Stan Weiss]

I have not worked with KRE HP heads. Did someone tell you to get 10.3" push rods, or did did you measure valve tip pattern with an adjustable push rod and come up with 10.3"?

Stan

[68hotbird]

used a pushrod length checker and set pattern. I moved the pattern all over the valve tip and no location on the valve tip will give pushrod clearance.

[steve25]

You may need a 3 piece push rod that has a different tapered end for the rocker arm side of it.

[Stan Weiss]

Just out of curiosity. What rocker arm ratio are you using?

Stan

[Gary H]

I'm sorry, please explain "none will clear the pushrod below the seat". I've built KRE high ports before and haven't run into issues. Trying to understand what you're running into.

[GTOGEORGE]

Originally Posted by 68hotbird

I am assembling a high port stock block engine Combo. It has a .440 lobe solid roller cam trend 10.300 length tapered end 3/8 pushrods and standard valves. I have 3 different rocker arms (Harland sharp, scorpion, and comp Red) none will clear the pushrod below the seat without a fairly significant amount of grinding. Just curious if this is fairly common with standard rocker high ports. Thanks for any info.

E mail jeff at KRE……..he reads his e mails in the morning.


GTO George

[Bill Eveland]

Are you talking about the bottom of the rocker over the retainer? I ended up using 10.4 pushrods and lash caps and still had some grinding to do. Im running 1.65 Crower SS rockers

[68hotbird]

I will try and post a picture. I had to grind on the vertical part of the rocker behind the trunion parallel to the pushrod its already scalloped there I just had to make it about a 1/16 of an inch deeper to clear.. The 3/8 pushrod even with the taper hit the rocker pretty hard. Hard enough to push the end of the pushrod out of the cup/seat.

[68hotbird]

here is a picture of what I had to grind for clearance

[mgarblik]

Could you also post a picture of the pushrod you are using? Manton has an extra long taper end that is pretty small toward the ball end. That may minimize some of the carving your having to do under the rocker arm.

[68hotbird]

here is a picture of the pushrods. Im doing this build for another guy who bought all of these parts from Kauffman as a package and Jeff said it should all work fine. Im anxious to see what he says once he sees the pictures. (engine was assembled and run the guy who put it together didn't catch the pushrod issue and it sent lots of shrapnel thorough the engine and killed a fresh build. He then brought it to me to see what I thought happened and to transfer his top end to another short block. I went to put this top end on a new 467 short block and found the clearance problem and all of the damaged pushrods and rockers. These are both stock blocks one 400 and one 455 and the geometry and binding issue is the same on both.

[68hotbird]

looks like trend offers a short and a long taper. The short (which I have supplied by Kauffam is 5/8 inch of taper. The long taper is 1-5/8 inch. Looks like a phone call to trend tomorrow and see if they are an on the shelf part or custom.

[mgarblik]

Thanks for the pics. Yes, those are some fat boys and will require allot of rocker arm carving. Trend makes some nice pushrods, but Manton Pushrods are the Ferrari of pushrods. Cost about the same and much nicer. They have a huge variety of options and are super nice to work with. Good luck with it.