1.6 roller rockers (Page 1/2)
jjd2296 JUL 04, 03:56 PM
Have a question. I have a 3.4 pr set up with a 260H cam and want to know if I can change my 1.5 rockers to 1.6 roller rockers without changing the stock springs?
BillS JUL 05, 04:19 PM
1 - the higher ratio rockers will wear the guides more quickly, if you care

2 - don't ask this sort of question on a forum, inquire directly from the vendor that made/sells the bits you have in the engine. Even if someone says you can get away with it doesn't necessarily mean that it is a good idea.

3 - the 260 cam is pretty useless - not much better than stock. The 272 is much better for a modestly improved engine.
pmbrunelle JUL 05, 04:33 PM
I'm interested in roller rockers that fit underneath stock valve covers as a possible fix for my rocker ball wear problems... so do let us know what works out.
jjd2296 JUL 05, 04:37 PM

quote
Originally posted by BillS:

1 - the higher ratio rockers will wear the guides more quickly, if you care

2 - don't ask this sort of question on a forum, inquire directly from the vendor that made/sells the bits you have in the engine. Even if someone says you can get away with it doesn't necessarily mean that it is a good idea.

3 - the 260 cam is pretty useless - not much better than stock. The 272 is much better for a modestly improved engine.



Well your not much help lol. 260h can with 1.6 rollers is basically 272. So answer me do I need to change the springs ?
lou_dias JUL 05, 04:42 PM

quote
Originally posted by pmbrunelle:

I'm interested in roller rockers that fit underneath stock valve covers as a possible fix for my rocker ball wear problems... so do let us know what works out.


One of the reasons why I switch to full roller ones...and why I made my aluminum valve cover spacers so they don't hit the valve covers...
Raydar JUL 05, 05:12 PM
If it's the Crane 260-1, then no. You'll bind the springs. It's why (IMHO) most people go for the 260 instead of the 272.
If it's the Comp 260, then... I'm not sure. It depends upon the lift numbers. (The Crane 260-1 uses "staggered" lift numbers. .427/.454, I/E . I believe the Comp is "square", but I'm not sure of the lift numbers.)
pmbrunelle JUL 05, 08:58 PM

quote
Originally posted by lou_dias:

One of the reasons why I switch to full roller ones...and why I made my aluminum valve cover spacers so they don't hit the valve covers...



How is it that ball pivots didn't work out for you (or for me), but they work for thousands of other engines? Were we doing something wrong?

I saw your spacer thread. Do you have extras for sale (just wondering)? I also saw other threads where people installed roller rockers beneath stock valve covers, so I guess the necessary clearance depends on the specific roller rocker that you buy.

[This message has been edited by pmbrunelle (edited 07-05-2020).]

Modesto JUL 05, 09:45 PM
I used the Crane 272 on my 3.4 build and not only did I need new springs, I had to have both exhaust and intake spring pads machined down to avoid binding problems. I was very careful to communicate to the shop that it needed to be verified, as I had read multiple horror stories of people only swapping springs and then finding out the pads were too high from the factory to avoid binding when they wiped the cam.

I'm with Raydar, the virtue of the 260 is being able to run it in an otherwise stock engine. I feel like the 272 is still quite mild in a 3.4 but I love how it performs. My head machine work was $600 for the complete rebuild, so it isn't cheap, but I like not having to worry.
La fiera JUL 05, 10:07 PM

quote
Originally posted by BillS:
the higher ratio rockers will wear the guides more quickly, if you care
.



That can be fixed very easy. The reason it wears is becasue the higher ratio changes the angle. If the guides are modded by elongating the slots you'll be fine.

[This message has been edited by La fiera (edited 07-05-2020).]

La fiera JUL 05, 10:12 PM
You should've have made the heads machined to accept Small Block Chevys springs.