The Mumm Bro's Dyno Archive

Background
Clearly, having more HP really helps win SRF races.  Driver skill is still paramount, but having an edge with the motor sure helps.  To that end, we spent LOTS of time researching how to "peak" the Ford Escort motor used in the SRF.  We did that on an engine dyno (you can't get sufficient resolution on a chassis dyno).  What we're presenting here are the results of those tests, which, until now, have been a closely guarded secret.
Dyno Info, Test Info and some Disclaimers
The Dyno
We did these tests on a Superflow 901 dyno in 1995.  The engines we tested were instrumented for A/F ratio at all times.  In addition, we took some baseline measurements of compression and leak down to calibrate the basic condition of the motors.

Test Information
The data is provided in the form an Excel spreadsheet I used to record the results.  Most of it is self explanatory, but there is some personal shorthand.  I'll try to clear up the majority of them here. 

The letters "S/A" or just "SA" stand for "Super America".  This is the gas station where we purchased fuel.  We specifically used their 90 octane for much of the testing.  This fuel had 10% ethanol.  You can see that we compared it to many other fuels and blends...particularly Amoco 93 octane (which didn't contain any oxygenates).

Here's some more info -- you're going to find out anyway -- when the notes say "+2 oz/gal"...this is referring to the amount of nitropropane added to the fuel.  Also, we tested several air filters that had been measured for air flow.  That's the CFM rating we gave them.  Also, there is something referred to as an "EGT" header.  This is a header we added individual exhaust gas temp thermocouple ports to.  We tested it to see if it made any performance difference compared to an unmodified header -- it didn't -- so for many tests, we just left it on.

Some tests have mention of "double humps" and "turning vanes"....these were little objects we inserted into the intake tube to see if messing with the airflow in the intake tube made any difference.

One last thing.  Typically we did 3 consecutive "pulls" with each different combination.  At the bottom of each set of 3 pulls, I averaged the data for all 3 pulls and provide those figures in bold in each section.  It's those bolded numbers I used to assess what a change did.

Legality Disclaimer
When you look at the data, you will see that we tested a lot of stuff that isn't legal.  We did this to find out if LEGAL work in an area would pay dividends.  There is no point in working on something that doesn't matter.

The Data
OK, here it is...the Mumm Brothers Dyno Archive.  This preceding link should open up an Excel spreadsheet giving you all the data and should provide hours of entertainment and probably some speed.

The bottom line:  much of this will probably not be of tremendous help to you...but just look at the results comparing a tight vs. a loose cam belt.  If nothing else, this data should point out the importance of keeping on top of your maintenance.  Another very valuable bit of info contained in the data relates to your driving.  The optimum shift points vary by gear...and this data lets you calculate what those shift points should be.

Rev. 9/9/07

Feedback
I welcome your comments or ideas on this information.  Feel free to drop me a line via “Comments for the Bro’s”.  

Barry

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