Rocker Question

**rbrack** · 02-12-2006, 05:48 PM

I just purchased a set of 1.8 rockers. Should I replace the pushrods, springs, etc. along with the rockers, or will the stock parts work alright? My motor has 42k miles on it.

**nhraformula** · 02-12-2006, 06:19 PM

upgrade the springs

**mrr23** · 02-14-2006, 02:33 PM

springs at a minimum. pushrods will get rid of some deflection, which is a net lift loss when they do bend.

**johuckabee** · 02-23-2006, 12:52 PM

stock push rods bend pretty easy. it only takes one weak link in the valve train to cause a failure. by the way, are you running a stock cam?

**mrr23** · 02-23-2006, 05:04 PM

me, yes.

**johuckabee** · 02-23-2006, 08:09 PM

The springs are your first hurtle. The valves float at 6500 with all stock stuff. Stock rockers are 1.7:1 but they are also made from heavier steel. So there is a trade off, the valve will move a little faster but there will be less momentum for the springs to counter. Stronger springs will counter float causing momentum. I would not worry. It will work just fine for now unless you rev the shit out of it. Stay below 6200RPMs for now.

**rbrack** · 02-24-2006, 04:34 AM

I am running the stock cam, although new heads and cam will be coming shortly. I haven't done enough research to decide which heads and cam to go with, as I really don't know enough yet.

**New Era Performance** · 02-28-2006, 05:55 PM

Usually aftermarket heads come with better springs , just install the rockers and heads and cam at the same time and you are all set . Otherwise , do the springs and pushrods when upping to the 1.8 ratio .

**Granatelli** · 03-01-2006, 05:11 AM

Features and Benefits of Granatelli Rocker Arms

Why Granatelli Roller Rockers?
Granatelli Roller Rockers are precision-engineered levers designed to overcome the inherent faults created by low cost factory rocker arms. Factory applications are prone to failure, which can result in an expensive engine rebuild. When combined with the proper Granatelli valve springs they offer a powerful performance punch.

How are Granatelli Roller Rockers constructed and what are the benefits?
Computer designed and machined, Granatelli Roller Rockers use a high strength extruded 7071 aircraft alloy that house hefty needle roller bearings and roller tips to reduce friction. A Granatelli Roller Rocker equipped engine responds more quickly than its standard counterpart.

In high performance engines with Granatelli Roller Rockers and stronger Granatelli valve springs, considerable horsepower gains are common over conventional rockers.

Will standard rockers covers fit?
The 1.7 Granatelli Roller Rocker Arm is designed to fit under the standard covers, but some may require taller covers. Often using two rocker cover gaskets glued together and longer bolts are a quick and easy fix.

What are the advantages of shaft mount rockers?
Granatelli Roller Rockers are designed for shaft mounting. This makes the rockers more stable and reliable at high rpms and in many cases results in a significant horsepower gain over standard stud mounted rockers, where the studs are prone to flexing, particularly where heavier springs are used in performance applications.

How can Granatelli Roller Rockers extend the life of my cylinder heads?
Standard non-roller rocker type arm push and pull the valve stem sideways every time the valve is opened. This causes the guides to wear prematurely, which in turn causes the valve seat to deteriorate. With a Granatelli Roller Rocker, the roller tip prevents this side loading, giving the guide and stem the best chance of survival, making them ideal for not only performance engines, but standard engines as well.

Do roller rockers need special push rods?
Usually no, with the exceptions being -
1 – When screw-in studs and hardened guide plates are to be fitted (on engines not fitted with them originally). These need hardened pushrods.
2 – When extremely heavy valve springs are fitted a more robust push rod than standard may be required.

What about my mileage?

While not sold as mileage enhancers, Granatelli Rocker Arms create an improvement in valve train geometry therefore the engine does not work as hard to “intake” the same amount of air which in turn means a more efficient combustion dynamic. This translates to better mileage while gaining an 8% to 11% increase in power.

A 10% to 15% improvement in mileage is not uncommon. This makes the Granatelli 1.7 shaft mount rockers a grand slam bolt on option for performance minded LS1, LS2 and LS6 based sports cars as well as all 4.7, 5.3 and 6.0 based SUV’s

Why are Granatelli Roller Rockers not color anodized to make them look fancy?
An anodized arm is weaker! Anodizing actually degrades the aluminum reducing its tensile strength and reducing the life cycle of the arm. Anodizing is an electrochemical process that produces a clear or colored coating. This coating is extremely hard and is "notch sensitive". Even slight "dings" from careless handling or slight scratches like those from feeler gauges can cause a "stress riser" precipitating cracking and subsequent arm failure.

Should I run a higher than standard rocker ratio?
Most cam grinders today specify rocker ratios higher than standard for specific camshaft grinds. We find in most cases the 1.7 ratio shaft mount Granatelli Roller Rockers gives you the best results.

I am fitting larger diameter valve springs. Will I have any problems?
It is imperative that you check for clearance between the rocker arm and the spring retainer combination in the fully open and closed positions. Allow at least .060" (1.5mm) clearance. The 1.7 ratio shaft mount Granatelli Roller Rockers have adequate clearance for most applications however those that don't can be notched by a competent engine machine shop for at a nominal charge.

What tappet settings do I use when fitting roller rockers?
The tappet settings remain the same as specified for your camshaft.

Should I reduce the oil supply to the top end when using roller rockers?
A roller rocker requires far less oil for lubrication than a standard type of rocker, so it is not uncommon for engine builders to restrict the amount of oil to the top end. Granatelli Roller Rockers incorporate an oil passage in the front of each rocker arm to supply oil to the valve spring. In highly stressed engines the cooling effect of the oil on the valve spring can be critical, so the decision to reduce oil supply should not be taken lightly.

What is the warranty on 1.7-ratio shaft mount Granatelli Roller Rockers?
We have so much confidence in the quality of the 1.7 ratio shaft mount Granatelli Roller Rockers they are guaranteed against faulty workmanship or materials for a period of 12 months from date of purchase This includes the extruded aluminum arms, precision alloy steel trunnions or shafts and posilok nuts.

Note: This guarantee is subject to the following conditions. You must be the original purchaser and produce an acceptable original sellers invoice. These warranties do not extend to cover faulty installation or maintenance or to subsequent damage whatsoever. The manufacturer, reserves the right to examine any goods under claim and shall be the sole judge of the validity of each and any claim and repair, replace goods at our sole discretion. All freight charges are the responsibility of the claimant.

**vettenuts** · 03-02-2006, 02:13 PM

New springs and pushrods should be installed, otherwise you will be running at high risk. If you can't do the pushrods and springs when you do the rockers, don't do the rockers.