The transformation form the stock 8.8" 3.27 to the Ford Racing Performance Parts 3.73 Gear and Pinion.
The quest of this project was not only just to change the gear ratio, but to see if I can actually gain additional horse power and torque by using a hardening process from Mikronite Technologies, http://www.mikronite.com/racing.asp My goal is to see if i can gain 8-10HP and 10-12 Pounds of Torque.
My Baseline Dyno results are 235.8 Horse Power and 277.5 Pounds of Torque.
The stock 3.27 gear and Pinion with only 16000 mile on them.
Old Gear and Pinion Removed, new bearing installed.
New Pinion Installed
New Ring Gear Installed.
Now I'm just waiting until I have time to get back to the Dyno to get a couple more pulls made to see if the $200 Mikronite process is worth any gain in Horse Power. Most people have no problem spending up to $100 per 1 horse power gain. My goal is to try and get the price per horse power down to $25 per HP. So if I get the 8 HP gain it will be the cheapest HP gain out there for your Mustang.
Below is the Dyno run after the installation of my 3.73 hardened/polished gear and pinion. The gain of 1 HP and 7 Pounds of Torque was compared as peak measurements only. As you can see in the overall curve it shows gains of Horse Power and Torque through out the entire band. I am getting the raw data from the shop to get the actual numbers and will put up a spreadsheet showing the actual gains. The plots are showing gains of up to 5 HP and 10 Pound of Torque. However the Back lash is set wrong and is whining like a crazy. So I will have to take the car back and get the ring and pinion set properly. I think I will see additional gains of 2-4 HP and 4-6 Pounds of Torque once its fixed. I will keep my web site updated as I get everything set properly and perform another Dyno run.
This site was last updated 09/27/06