Let it flow, let it flow, let it flow!

Online-Racer’s 347 Stroker Project get’s a 76mm Mass Air Meter Upgrade

By: David John Stevenson

Oh yes, life is good!  You’ve just bolted on a cold air kit to your mass air equipped 5.0 Mustang. You must be flowing' some serious air now huh? After all, you can hear gobs of air rushing into your intake. Is your intake system really optimal yet?  Before you call it a day and head out to the local races, you must address the other components of your intake system.  Most people throw on a bigger throttle body next but are quickly humbled by lack luster power gains.  What’s the weak link in the stock 5.0 intake system?

The old speed density 5.0’s (1986, 87 and non-Cali 88) had a large intake tube that flowed mostly unrestricted all the way to the throttle body.   Not so on the 1989 (88 in Cali) and later mass air equipped 5.0’s, most of these cars suffered from a small diameter (55mm) mass air meter that choked the incoming air.  The stock mass air meter is generally considered a weak link when increasing airflow on these older non-Cobra 5.0 set ups.  The Cobra and Cobra R based 5.0 variants were equipped with larger mass air meters to help feed bigger than stock throttle bodies and intake manifolds.         

For a replacement on our 347 Stroker Project, we decided to run a 76mm C&L mass air meter.  Our decision to use the C&L was two-fold.  First off, it's one of the best buys on the market and secondly, it uses the existing Ford mass air electronics for a simple and straight forward swap.  The C&L’s 76mm meter not only increases air flow volume, it’s straight through design is much more efficient than the stock meter.  

When purchasing the C&L meter, you must decide what sampling tube is needed for your particular application.  These meters can be purchased with sampling tubes that match the most popular Ford injector rates. For our project, we bought it with a 19 lb sampling tube (Yellow) and ordered an additional 24 lb tube (Blue).  The 19 lb tube should be used with the original 19 lb injectors but our 347 engine equipped with 24 lb injectors required the larger 24 lb tube  . 

With the addition of the C&L meter, our airflow will have a mostly un-obstructed path from the hi-flow air filter in the fender all the way to the throttle body.  The inside diameter of both our cold air intake tube and the C&L meter are approximately 3 inches or 76 mm.  Airflow gets a little turbulent when it reaches the stock “accordion shaped” plastic elbow but that can easily be rectified with an aftermarket elbow in the near future.  C&L has one that can be ordered with the meter or bought separately.

The C&L came with complete instructions and is a breeze to install.  It simply bolts right on to the existing factory bracket and lines right up with the stock elbow.  The only trouble we had was squeezing the stock elbow over the new C&L meter.  A little elbow grease and patience got the job down in only a few minutes.  Just be careful not to damage the stock elbow in the process, some heat or soapy water can really speed things up for the seriously impatient.

Since the new C&L utilizes the stock Ford electronics, all you have to do is follow the detailed instructions and carefully remove the sensor and electronics from the stock meter and install them on the new meter.  The sampling tube is located in the new meter and acts as the housing for the sensor.  The sensor is actually a heated wire that meters and tells the computer how much air is flowing through the system.  It is very important to follow the instructions and handle the sensor with care to prevent possible damage.  This would be a good time to clean the sensor.  Make sure you only use a dedicated mass air flow cleaner since other solvents like brake and throttle body cleaners will be too harsh.

C&L recommends using the factory air box or an enclosed air filter to prevent a surging idle caused by "fan wash".  If you decide to use an open conical filter, they strongly recommend using a shield to keep "fan wash" and heat from penetrating the air filter.

We actually took off our existing cold air intake and tested the C&L with an un-shielded K&N conical filter.  This confirmed C&L’s "fan wash" theory for us.  With the un-shielded filter, we could not keep the car running at idle for more than a few seconds.  This continued every time we tried running the engine until we re-installed our enclosed fender mounted cold air kit.  On our particular set up, the “fan wash” problem may have been intensified by our (always on) “clutch-less” flex fan?   Regardless, with our new C&L in place and the fender mounted cold air re-installed, we fired it up and found the idle to be smooth and steady. 

Depending on your existing modifications, C&L claims a bolt-on increase of between 10-16-rear wheel HP.  On the road, the car felt crisper and more responsive to throttle activity.  This was especially noticeable at highway speeds or when we “goosed” the throttle a bit.  Intake noise is increased slightly but who’s complaining, a little noise for some extra power sounds like a good trade off to me?