Split duration?

[Todd Hedges]

Originally, the 428 I have in my Cobra was built with a split duration cam.

Once the distrb. gear failed, and I had the engine re-built, the
cam was replaced with a similar profile except...

the exhaust duration is now equal to the intake.

I understood that the whole reason for the split-duration
profile was that the FE exhaust valves were dis-perportionately small, and the added open exhaust time allowed for better performance.

The intake profile on both cams is the same.

Will there be any noticable loss in performance with this change?

I realize it's likely to be so small that an average Joe like me, will
never notice. I'm just interested that's all.

Thanks

[A Snake]

For general driving, you'll probably never notice it. Even if you push it once in a while, it's still going to have more than enough power to scare the daylights out of you.

Frankly, for the average guy, trick cam profiles sell camshafts and are the stuff of endless "bench racing" discussions, such as much of what is discussed in these forums.

The serious racer will spend a lot of time with his engine builder and chassis tuner, figuring out just what combinations work and what don't. In this environment, seconds matter.

In the real world of everyday driving these cars, a nice cam lope, burbling out of the side pipes and the ability to "light the tires" once in a while is good enough for most of us.

At best, 1% of those who own and drive replic Cobras, have the ability to utilize the full potential of the cars. The rest of us just wish we could and are smart enough not to push our luck too far.

Al