Rocker arms

Hulk_smash

New Member
Feb 14, 2016
26
Sanford FL
I have a flat tapper cam but i wanted to know if i could use a roller rocker arm i mean i don’t wanna mess anything up or lose power
 

COPO

Veteran Member
Lifetime Gold Member
Sep 15, 1999
23,083
The Moon
This is what I'm using (with guide plates) 1.52 Comp Magnum Roller Tip Rockers, part # 1412-16 compared to the stock Z28 rocker arms.
They work with both FT & roller cams. If you don't have guide plates then remember to use the other part # you'll need to look up.

comprollertip.JPG
 

MyBoTy

Veteran Member
Feb 9, 2002
1,567
Lubbock, Texas USA
Roller tips do very little to help other than reducing the size of the contact patch. Spintron testing shows the rollers don't actually roll over the tips of the valve but slide instead. They do seem to help reduce side loading on the valve, though.
The full roller rockers help a bit more, but most of that is from better geometry than reduced friction or anything else to do with the roller fulcrum.
None in the pics are self-aligning.
 

CorkyE

Veteran Member
Lifetime Gold Member
Nov 4, 2004
12,033
Ringgold, GA
I hopped on the roller rocker band wagon many years ago when I saw the improvement on a SBC we put together with old fashion long slots, then switched to rollers. Friction is going to increase with higher lift cams and GM has done away with the fulcrum ball type rocker on the LS platform. Like said above, don't use self aligning with guide plates.
 

GoldenOne7710

Equal Opportunity Offender
Lifetime Gold Member
Jun 23, 2004
5,707
Athens, GA
Roller tips do very little to help other than reducing the size of the contact patch. Spintron testing shows the rollers don't actually roll over the tips of the valve but slide instead. They do seem to help reduce side loading on the valve, though.
The full roller rockers help a bit more, but most of that is from better geometry than reduced friction or anything else to do with the roller fulcrum.
None in the pics are self-aligning.
In comparison to a standard stamped steel rocker, you can get some deflection and distortion when using a higher lift cam and a stamped steel rocker. This can yield inconsistent valve lift across the entire valvetrain...which amplifies at higher RPM's.

The roller tip units actually are more rigid and that inconsistency is pretty much nonexistent. Valve lift accuracy maintains at nearly every RPM range the cam is capable of. Is it a benefit on a street engine? Everybody will have their own opinions about it. I personally won't run any stock valve train hardware if the camshaft is larger than stock.
 

Z28500

Member
Jan 26, 2017
49
Yes you can upgrade

there are roller tips and there are full roller rockers Look at the pics

Anything you can do to reduce friction makes power. Personally, I wouldn't mess with the roller tips. Though we’ve built a lot of circle track engines with them because of rule limitations.

Stay with 1.5 ratio and when you install them.

Close the valve(base circle) and turn the pushrod with your fingers, it should rotate freely without moving up and down. Then tighten another 1/2 turn. Look at the diagram of the cam lobe I put up.

Here is a rule of thumb for making Power =

As Much Compression as possible 10:1 Usually for 93 octane, sometimes more-

Reduce friction (Roller Rockers & Lifters/Cam & even Teflon bearings) & build the engine loose.

Reduce weight (Rotating assembly, valve train, transmission components & Anything else, cars weight etc),

Optimum Burn- Volumetric Efficiency (zero deck block, low quench area, (Mines at 0.040”) and ignition timing (I’m at 36 degrees)

There is No Replacement For Displacement -MORE Cubic Inches The Better

AND--- the thing most “Hot Rodders” forget-BRAKES-They fade at high speed

There is way more than what I typed which is just a starting point

I built an engine 10 years ago with about 9:1 zero decked block with stock 882 heads (325hp) and took it to get smog tested without cats on it. It burned cleaner than most new cars that came in.

Zero decking is one of the things you do to “blueprint” a block. That and align lifter bores, main bearing bore alignment, But zero deck and a perfect straight line for the crank to spin in is most important (Cam too)

Get rotating assembly balanced

My block is low filled with epoxy for strength and runs a perfect 185 degrees. (Low filled to the bottom of the cylinders)

VERY LAST=Cubic Dollars

OUCH
 

Attachments

  • Crane Roller Rocker Gold Series 1.5-1.JPG
    Crane Roller Rocker Gold Series 1.5-1.JPG
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  • Cam Base Circle-2.JPG
    Cam Base Circle-2.JPG
    29.1 KB · Views: 154
  • Roller tip.JPG
    Roller tip.JPG
    33.9 KB · Views: 186

JordanZ28

Member
Dec 26, 2017
68
Yes you can upgrade

there are roller tips and there are full roller rockers Look at the pics

Anything you can do to reduce friction makes power. Personally, I wouldn't mess with the roller tips. Though we’ve built a lot of circle track engines with them because of rule limitations.

Stay with 1.5 ratio and when you install them.

Close the valve(base circle) and turn the pushrod with your fingers, it should rotate freely without moving up and down. Then tighten another 1/2 turn. Look at the diagram of the cam lobe I put up.

Here is a rule of thumb for making Power =

As Much Compression as possible 10:1 Usually for 93 octane, sometimes more-

Reduce friction (Roller Rockers & Lifters/Cam & even Teflon bearings) & build the engine loose.

Reduce weight (Rotating assembly, valve train, transmission components & Anything else, cars weight etc),

Optimum Burn- Volumetric Efficiency (zero deck block, low quench area, (Mines at 0.040”) and ignition timing (I’m at 36 degrees)

There is No Replacement For Displacement -MORE Cubic Inches The Better

AND--- the thing most “Hot Rodders” forget-BRAKES-They fade at high speed

There is way more than what I typed which is just a starting point

I built an engine 10 years ago with about 9:1 zero decked block with stock 882 heads (325hp) and took it to get smog tested without cats on it. It burned cleaner than most new cars that came in.

Zero decking is one of the things you do to “blueprint” a block. That and align lifter bores, main bearing bore alignment, But zero deck and a perfect straight line for the crank to spin in is most important (Cam too)

Get rotating assembly balanced

My block is low filled with epoxy for strength and runs a perfect 185 degrees. (Low filled to the bottom of the cylinders)

VERY LAST=Cubic Dollars

OUCH
hi there,my z28 78 Camaro need rocker arm replacement, i looked online for a bolt one upgrade, is these roller rocker are direct replacement or need to modify anything to install them, my engine is still stock in every point is this will effect my engine or upgrade it , what you think?
 

CorkyE

Veteran Member
Lifetime Gold Member
Nov 4, 2004
12,033
Ringgold, GA
With your completely stock engine, it's highly unlikely you will see any performance upgrade with roller rockers. Why do you need to replace rocker arms? The rarely wear out, go bad, etc.
 




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