Roller Rocker Questions???????

[Ted Bromback]

Do they make roller rockers 1.5:1 or 1.6:1 that fit the stock rocker shafts on my 360 "j" heads? If so what else do you have to replace? and IS it much of a torque gain, and lastly about how much does it cost? A lot of Novice Questions......I expect to get some wild answers.

[rumblefish360]

Roller rockers and regular adjustable (Non roller) rockers are made in both ratio's. You may have to change your springs due to the new lift. Ex; Your springs are rated @ / for cams with a lift of .500. Your cam is .500 lift. There matched. OK fine now, until you use 1.6 rockers. To figure out our new lift, divide 1.5 (Standard rocker ratio) by the cams lift at the valve. Then multiply by 1.6 for the new lift.

.500 / by 1.5 = .3333333333
.33333333 X 1.6 = .533

Time for new springs.

Where do you stand now?

Torque and HP gains are small. The head must be able to use the new lift to its advantage or it is a small waste.

Mopar performance sells them.

[Ted Bromback]

I appreciate the calculation tip on that valve geometry.
I saw two different sets of aftermarket roller rockers on ebay, one by C.A.T. of Ca and another from GearsAreUs.com, and it appears that they might fit on the stock shafts(although they offer hardened shafts) and don't require different pushrods etc. Would this work on an "under 400HP" street engine. How about oiling?
On Dyno 2000 program they boost torque by 50 ft-lbs.

[rumblefish360]

50lbs. on a program isn't 50lbs. in real life. Use computer programs for comparing and outlooks. If you increase 50lbs. real world with this 1 upgrade, I would not be looking at cat products. Look to Crane or Harland sharp products. Race tested and approved for servere poundings.
"Cat" is made in China.


Oiling is done the usaual way. No problems with your oiling now is there? No need for trick or hollow pushrods. Just the correct length and ends on the pushrod.
The rockers have a different end to them then the regular Hyd. pushrods.
The Hyd. p-rods are balled on both ends.
The adjustable p-rods need a cup up top and a ball on the bottom. The cup up top of the the p-rod excepts the adjusting screw of the rocker.

[71383bee]

I have too contemplated roller rockers and unless you are going to the 1.6 ratio (Be sure you have the proper clearance!) they are not worth the high price for a mild performance street engine. For good Harland Sharps or Comp Pro Magnums they are around $400+. Even Hughes recommends sticking with the stock style rockers unless you are seriously going to be at the track more often. Check out there site i know he talks about it in there somewhere Heres a link www.hughesengines.com

Actually the stock shaft mount rockers are pretty stout and can take a darn good beating.

CAT rollers are from china and cuda will disown you!

Seriously though there are a few guys on here that were using them and I don't remember any complaints.

rumblefish makes a good point about you springs. Be sure that they match the requirements for your cam. This is far more important than going to rollers.

I look at it like this. Try out the stocks for know and if you have the clearance go for the 1.6 rollers at a later date when you have the dough. You don't need to mess with the heads to change rockers.

[451Mopar]

You can get both ratios in roller rockers. The Crane gold aluminum roller rockers, and most others only have a roller tip, they are not full rollers where they mount on the shaft. The Crane roller rockers are about $330 for the rockers and shafts, but because these are adjustable, you need to replace the pushrods for use with the rockers adjusters.

The higher ratio 1.6:1 rockers have more valve lift, and if the heads flow more air at the higher lift (they should if the cam lift is under 0.500") the engine should make more power. Some poer benifets may also come from being able to adjust the lifter pre-load, and the roller tips may reduce friction also. Also, the stock stamped rockers often have a true ratio less than 1.5:1.

The cautions of using higher ratio rocker arms relate to valve lift, you will need to check piston to valve clearance, valve guide to retainer clearance, valve spring coil bind, etc.

Because the higher ratio rockers move the pivot point of the pushrod closer to the inside of the rocker arm, the pushrods come close to hitting the inside of the pushrod holes where they go through the cylinder head. Mine cleared without modification, but I am using a fairly mild cam.

[jelsr]

I have seen in this forum, somewhere, that the stock stamped rockers are not a true 1.5 but are closer to 1.4. Another thought is to be sure you won't have the valves and pistons smooching one another, it's not pretty. MP lists pushrods for hyd lifter and mech rocker combos.

[Ted Bromback]

Thanks Men of Mopar. I've decided, too much money and trouble for what I need right now, but as usual, I learn a little more each day by reading all these posts.
Again, I appreciated it!