MASS AIRFLOW SENSORS:

What is cold air tuning and when do I need it?
Cold air inductions significantly increase airflow and can cause tremendous turbulence in the air intake stream.  When using the GMS mass airflow sensor with any type of cold air induction, high flow induction, or high flow air filter, your GMS mass airflow sensor must be calibrated with cold air tuning or a check engine light can occur.   Cold air tuning is designated by a "C" as the last digit in the part number.  Cold air tuning is also available for existing GMS mass airflow sensor owners - please call 805-486-6644 for details.

Will it void my manufacturer's warranty?
No. The Granatelli Motor Sports mass airflow sensor is a rugged, OEM approved replacement mass airflow sensor.  Every sensor is backed by a 90-day limited warranty against defects in materials and workmanship. If you need to make a warranty claim within the warranty period, all warranty returns are handled through your authorized Granatelli Motor Sports dealer.

Legally, a vehicle manufacturer cannot void the warranty on a vehicle due to an aftermarket part unless they can prove that the aftermarket part caused or contributed to the failure in the vehicle (per the Magnuson Moss Warranty Act, (15 U.S.C. 2302(C)) . For best results, consider working with performance-oriented dealerships with a proven history of working with customers. If your vehicle manufacturer fails to honor emission/warranty claims, contact EPA at (202) 260-2080 or www.epa.gov.  If federal warranty protection is denied, contact the FTC at (202) 326-3128 or www.ftc.gov. 

I dynoed my vehicle and my horsepower and torque numbers vary from the numbers you claim.  Why did my test yield different results?
Performance figures shown can vary considerably due to a variety of factors including but not limited to altitude, humidity, barometric pressure, outside temperature, vehicle age, state of vehicle tune, vehicle manufacturer engine tolerances, vehicle modifications, chassis and engine dyno calibration, chassis and engine dyno brand, etc.

What is a mass airflow sensor?
The mass airflow sensor meters the CFM (Cubic Feet Per Minute) of air as it enters the engine via the throttle body.  Ford and GM vehicles use hot wire style sensors.

What's different about the Granatelli Motor Sports mass airflow sensor and stock?
Most stock Ford and GM mass airflow sensors are 65-70mm in inside diameter. The Granatelli mass airflow sensors are 81mm-90mm, featuring 47% more airflow capacity than the stock sensor.  The advanced, active-electronic module packaged within the sensor provides improved control of injector timing and ignition timing.

How much more horsepower will it provide?
Typical horsepower gains are 10-23 horsepower at the rear wheels.  Usually, customers exceed our claims.

Where will I notice the extra power?
Typically, from 2000 rpm throughout the entire power band. Towing, passing power, and throttle response are significantly improved.

Will it affect fuel economy?
While we do not sell our mass airflow sensors as mileage improving devices, it typically requires less throttle angle to achieve the same speed. Therefore, you will see an increase in mileage if you maintain a calm driving style. However, if you drive aggressively nothing can improve mileage.

Are they 50 state legal?
Yes. Granatelli Motor Sports is the only mass airflow sensor that is 50 state legal for popular late model Ford and GM engines with electronic fuel injection. The CARB E.O. number is D-471 through 2002.

Will it work with aftermarket modifications?
Yes. The Granatelli Motor Sports mass airflow sensor has the ability to automatically compensate and calibrate for typical modifications.  Custom calibration is required when running larger fuel injectors with Ford mass airflow sensors.

Does the computer relearn the fuel and timing curves canceling out any performance gain?
No. GMS mass airflow sensors are "truly calibrated" on our proprietary computerized flow benches and plays no tricks on the factory ECM/PCM.

What are the disadvantages of home porting or larger aftermarket billet ends?
1.  They are for off-road use only
2.  They are not calibrated so the factory computer will “learn out” these modifications after 200 miles negating any performance increase
3.  They cause the engine to run lean

The only solution is to use a "truly calibrated" mass airflow sensor from Granatelli Motor Sports.
 

Can a GM mass airflow sensor compensate for fuel injector size changes like the Ford sensors do?
No. Due to the inner-workings of the GM style mass airflow sensor, they do not have the ability to compensate for fuel injector changes like the Ford sensors can. In fact, this is another great feature offered only by the Granatelli style Ford mass airflow sensor. On Ford applications, we have the ability to calibrate the meter internally so that simple fuel injector upgrades can be made to your engine without sacrificing idle and drivability quality. Yet, you can gain big performance improvements by allowing the engine to receive more fuel under heavy load conditions.

Is it easy to install?
Yes. The installation takes 10-15 minutes with simple hand tools (exception are Ford slot-in mass airflow applications which include an integrated cold air intake system as these systems will take longer). To ensure an easy installation, every sensor includes detailed instructions.
 

Where can I purchase Granatelli Motor Sports mass airflow systems?
All sales are handled through authorized Granatelli Motor Sports dealers.  You can locate your nearest dealer by calling our dealer hotline at 888-600-9011.

ROLLER 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 rpm’s 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 a s 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 workman! ship 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.