Here we go again? Roush

[greg schroeder]

Originally Posted by Got the Bug

Good point Greg. They've probably built ~2,000 402s/427's, and most end up getting installed in Cobras. If your going to see issues reported, it's going to be here on Club Cobra.

Just curious, what was the minimum octane you would run in your Cobra? All of the major builders advertise that their engines can run on standard pump gas, so why would Roush be any different (unless they're all wrong ) ?

There are a number of stations around town that have 100 octane unleaded out of the pump in Scottsdale. I'd usually be between 97 and real close to 100 octane, but mix down to 95 or so at times if the good stuff wasn't handy. The car made 475 at the wheels on that. You'll be going backwards in power if the octane goes much higher on the tune I had. Put in 91 from the pump on the same tune and you'll be binking up some pistons while the side pipes drown out the ping noise. That doesn't seem to be uncommon for people with Roush engines, but not for me.

The fuel varies greatly even with same octane from state to state and even city to city from the pump. Go to Detroit and you can buy some nice 95 octane "pump gas". Here in Scottsdale who knows what mix of addatives you'll end up with given 91 octane "pump gas".I guess anyone could back out timing, run lower octane, have less power and be safe and send out an accomanying engine dyno on a diffrent tune. I passed on the Roush "recall" to have the timing adjusted on my engine.

Given a properly set up engine one guy in five minutes can thrash a new cold egine more than a responsible person might in 20,000 miles.