EVO X Test and Tune.....part 1

Many of you have heard about the internal EVO X vs. 08 STI battle at PERRIN we are having.  This should be a real fun thing to watch progress over this summer, but our first installment of this battle is our EVO X initial testing.  Unlike some of the future EVO vs STI articles, this one will be totally unbiased.  All PERRIN test vehicles start with a baseline run to establish a starting point for the future mods. Below are our results.

First lets explain the dyno and testing methods we are using.  In Oregon, we have 92 octane, which is not as “cool” as you East coasters, but it is a step above the CA, AZ, NV guys with 91 fuel.  So using that fact our car should put down numbers a little higher than 91 guys but a little lower than east cost guys.  What is strange is that we are seeing slightly higher numbers than others are putting down.   Our dyno we are using is a Dynapack dyno.  This isn’t a dyno that reads high, or really low.  In fact it seems to be pretty close to the mustang dyno in how it reads for most cars.  All of our runs are done in 4th gear, and run for 14 seconds.  Both of these factors play into the actual HP and TQ numbers we see.  These factors are important to mention and important to understand as they can be manipulated to change the results.  We could have made the dyno read a bit higher, by changing to 3rd gear, or making the run shorter, but for tuning purposes, and future part comparos, this is what we decided on.

The first 3 pulls really amazed us, they were very consistent.  We were used to the STI, where the dyno runs can vary 25WHP with the ECU constantly testing the knock threshold.  With 5 runs under the X’s belt, we saw an astonishing 260WHP and 280ft-lbs or torque!  These seemed a little high compared to other peoples results, but they are very consistent, and a great starting point for future parts. 

 
Our TQ numbers are a little higher than some have seen, some of this has to do with how the Dyno launches the car. This is one of the best features of the Dynapack dyno.  We tell it to start at a given RPM the tell it to hold the car there for a given period of time. This lets us make the runs very consistent and launch the same every time.  For us we started the runs at 1500RPM and end at 7400. As you can see this make the runs pretty consistent.  Consistency is another important thing to us.  With all results we show, these are backed up by several other runs. The we take the averaged gain, not the highest gain.

 
One thing we just couldn’t believe is how rich this car runs!  Some were reporting 9.5-1 AFR’s, and I just couldn’t believe it, but sure enough, we saw about the same thing.  These results are behind the cats, so that is a good full point AFR leaner.  The other blue line is the next thing we did to the X while we had it on the dyno.  A PERRIN manual boost controller was used and adjusted to a peak boost pressure similar to stock. We were seeing about 23psi of boost, so we turned up our MBC to 23psi.  Below is the stock boost curve compared to the MBC boost curve.

 
As you can see the EVO boost is a little slower, and drops off more toward redline.  More boost equal more power!  The peak power went from 260 to 300! This is huge!  While the peak number is much higher, what about the midrange and low-end power??  

 
At 23psi we make more TQ at lower RPM and a lot more at redline.  Horsepower really went up from 6500 on up.  The only thing is the huge drop in power at 6200RPM.  This looks to be from the ECU pulling timing as it might have heard knock.  Even so we never audibly heard knock.  I think that 23psi is perfectly fine with the ECU and I would pretty confident that anyone with an X could buy our $90 part and get 40WHP from it!  Before we pulled the car off the dyno, we did a couple runs at 25psi, and found even more HP…but.

 The “but” is how consistently; the runs were getting detonation, or at least looked like it.  That huge dip in power at 5500 was there on 5 runs and while we didn’t hear anything, it was a sure sign of the ECU not being happy.  I suspect misfires from being soooo rich.  With minimal mods and still no tuning or parts installed, this is showing great potential.
Check out this video we made showing off our first experience with the X.

So how does this compare to the 08 STI?  It takes the cake for most HP in stock form.  Below shows the EVO making almost 30 more WHP than the STI. 

But add our stage 1 AccessPORT tuning and we start to see where the EVO will loose out.  As I would suspect as our battle progresses, we will see the STI make more low end power, and the EVO make more top end power.

 
With the EVO running as much boost as it is, it doesn’t really have that much to gain at low RPM. But in midrange and top end, the EVO should do well with its bigger turbo.

 
This is the EVO running 25psi compared to our Stage 2 STI with turbo back and a tune.  

Conclusion

So besides the constant black cloud coming off the back of the car, the car shooting fire out the tail pipe, this thing was making some big power! And to kick off our EVO X vs. 08 STI battle, chalk one up to the EVO for most WHP in stock form. More tests will be done over the next few days after our turbo back exhaust is installed and intake and FMIC.