The big question is:do I need new pushrods?Is there difference at valvetrain geometry?

 

I can't see it. It can't hurt to check, but it'd surprise me if there was any new issue.

 

The Comp Pro Magnum RR's require longer studs.

RBob.

 

Do you know how long?

 

With any change of valve train components you should always measure to ensure you have correct pushrod length to get proper rocker engagement on valve stem
Not all engines the same

 

I will check with marking colour that roller tip is middle of valve stem.
When I measured overal stud height it was 1.7".
I measured also how much there is visible thread at stud when valve is cloced.At top of stud to top of trunion distance is 0.366".Is this too short?
If it is too short is ARP #134-7104 right stud to pro magnums?Those ARP studs have overal stud height 1.896".

 

DO NOT BUY CHEAP EBAY ROCKERS!!! I just bought a set and it was junk $110 WASTED! Do yourself a favor and go up a notch to at least the cheap brand name stuff, an extra $100 is cheap insurance for causing problems in your engine!

 

Valvetrain geometry is cheked now.Seems that I need to buy shorter pushrods.Current ones are 7.18" overall lenght (5/16 diameter),and wear mark at valvetip is not coplety centered.
With adjustable pushrod(adjusted to 7.1") wear mark is centered.
Any recomendations what brand,material,hardened or not etc. should I buy?

 

if your running guide plates then you need hardened pushrods the rest depends on the lift of the cam and the spring pressure
if its an aftermarket cam go with their recomended pushrods if possible cheap alternative is summit pushrods on the cheaper side and still hold up pretty good

 

I have stamped steel roller tip Elgins in the 350 in Berlinetta #1, and have had Magnums in the 396 in the '57 since 1997. I didn't have to change pushrods with either one.

I just installed Ultra Pro Magnums in the 396, which include poly locks. No valve train geometry problems, same pushrods, same rocker studs.

 

i'm rather suprised at some of the response . i have comp cams roller tip 1.6 ratio on my car now . pn# 1416-16 , they are not the first set i have used . no problem with stock pushrods if you have the same pn# . good luck .

 

I used Crane studs # 99157, which IIRC is a BBC stud. It is 7/16" top & bottom. Used guide plates and a hardened washer under the plate. The washer was required as the threaded portion that goes into the head was a tad too long.

This put the top portion of the stud at 1.81" in length. The stud being 1.76" and the washer being about another 1/16".

I would say that the 0.366" is borderline for a 3/8" stud. And not enough for a 7/16" stud.

RBob.