Should I Upgrade Cams, Valves, or both?

If you are building your engine to make more power, there are a couple of things to consider.  You definitely want a turbo that can make the power that you are building for, and a shortblock with pistons, etc., that can hold the power.

But what about the valvetrain?  The cylinder heads, cams, and valves play a key role in getting air and fuel into and out of your engine.  The valvetrain as a whole determines when and how your engine will make power, and that is a big part of how much useable power your engine will make.

So when should you consider an aftermarket Camshaft?  Larger valves?  Or both?

For this question of the week, we discuss this question and take a look at two cars in our shop that are a good example to contrast the benefits of each.

Specifically Nigel's WRX race car, and our Pikes Peak race car.

Nigel is running the RCM-400 turbo, which is only one step below the Turbo Dynamics MDX55-450 that we are running on the Pikes Peak car.

Both cars are running E85 as fuel, have EJ25 engines, and Front Mount Intercoolers.  

But relevant to this conversation, Nigel's car has GSC Stage 2 cams (272 duration) and oversized valves, where as we have the stock valves and cams on the Pikes Peak car. 

Now there are some details that don't make this an ideal comparison, the main one being that the Pikes Peak car has AVCS and 2.5 liter heads, and Nigel's car is non-AVCS with S20 heads.  But these two cars are still so close, especially in turbo size, that this is a good starting place to see what upgrading your valvetrain does. 

Hopefully this video helps to answer some questions and give a little more context about where and when you would want to look at upgrading your cams and/or valves.

Thanks for watching and Stay Tuned!