EVO IX turbo is "stock" with regards to most class rules.

Minimize pressure drops and improve efficiency where ever possible and it will give you gains.

I have an '05 turbo and am after the same thing. I have done quite an extensive amount of porting on the stock turbo, both intake and exhaust sides. I'm also working on a little mod that will lock the wastegate completely shut at the flip of a switch but allow normal operation as well.

Consider going from Q16 to E95. The added cooling of the alcohol evaporation could help out. Octane isn't the only thing that matters.

 

Also, one thing to consider is the VE of the engine, from what I've been taught/told, more aggressive cams or other engine "breathing" mods will actually let the engine consume more air, which keeps the turbo from pressurizing so high... it doesn't mean there is less power being made.. (this of course, is on paper... what happens in reality might be different )

Nonetheless, I'm interested in why I make peak HP so low in rpm, even when the cam gears are adjusted for more high rpm power, the engine will not produce more in those rpm's, (minimal, like 5 HP) only creates lag... moving the cam gears back for more midrange does not lose the higher power, just adds more torque and broadens the response... seems like the turbo is the culprit.

I'll be trying out a cone intake soon!

 

Actually, I DO worry about that, which is why boost leak tests are important.... I feel that if all the air is actually going into the engine instead of leaking out through even small leaks, the turbo will be much more "controlled", but maybe my thinking is off abit on that

 

Bit normal with high boost on the stock turbo, with the taper and the restrictions you still have. Even with out the restrictions it will still be like that, It just can't breath up top.

Here is an example from our dyno on a Evo 9 with stock turbo, open filter, a somewhat restrictive exhaust, and the normal supporting mods. The higher curves are on 100 oct with 28 psi peak, the lower curves are on 91 octane with around 24.5 peak. You can see on the 100 tune where the stock turbo just can't breath much more and the two hp curves start to come together:



btw, this is a ecu-boost equipped Evo. On 100 oct it's holding around 22.5psi at 7,400k.

Here is the boost plot on 91 octane:

 

Razorlab......

When you say stock air box to open filter does that mean the stock air box has a drop in or the stock filter?

 

With the examples I gave, yes they had aftermarket drop-in filters.

I did a test awhile back on aftermarket drop-in filters. 5 different ones. 4 of them made within 2 hp of the stock filter, one of them made 4whp more (ralliart). Each one I ran for 3 runs with proper cool down between each different filter.

Testing if a open filter will give you any gains is pretty easy. Just pull the top off the stock airbox and pull the filter and do a run. I've done this quite a few times on customers cars. Some jump up a ton of horsepower, some do not.

Here is some data between a stock airbox and a open filter (run 2 and 3):



As you can see the IDC went way up with the open air filter, for the same AFR and boost levels as before. It's using more fuel to keep the same AFR, which in my book, means more real airflow.

Before the open filter it made 321whp/308wtq. After it made 337whp/316wtq. Peak gains of 16whp and 8wtq. However it also gained more throughout the whole curve. I'd post the dyno overlays but I can't seem to find them right now.

I did the test of pulling the drop-in filter and airbox top before swapping to the open filter. It gained peak 25whp/20wtq from doing this. Some of that is because the boost went up a bunch and it leaned out a bit. After tuning it back down to safe levels on 91 octane, with a open filter on (since people don't drive around with open MAF sensors) , the peak gains of 16whp/8wtq above where seen.

That is one example. My personal Evo gained 24whp/11wtq from moving from the stock airbox to a open filter (still stock induction tube). Same boost and AFR as with the stock airbox.

 

sweet !

 

Yes, thanks for the great info razorlab, I just have to do some reading up in the ECU flash forum and see what all is going to take to get the car running right when I do the swap!
Thanks again!

 

I didn't realize you didn't have a ported exhaust manifold. . . here is my updated list of mods for you . . .

- ported and ceramic coated exhaust mani, BR or PPI
- ported hotside
- HKS 272 or 280 cams
- BR UICP
- Nisei mini battery kit (so you can run the UICP)
- open intake (TBD)

 

I'll be doing the porting soon, however I'm not sure on the cam thing, can HKS be BETTER than the Comp cams 280's? I'm not so sure, it took me a long time to pick those out, granted it was before GSC launched the "S" series cams, but still, the cam specs seem to favor the Comps over the HKS

 

The "specs" said my Revolver cams were "better" than the HKS 280's . . . but you know how that turned out. . . .

Try to step back from thinking what a part "should" do, and take a look at what it actually has done on your application. You hit peak HP at 5000 RPM. That, to me, signals a problem . . .

The main difference between my car and your is :
ported exhaust manifold
GSC S1 cams vs. Comp 280's
Green vs. Evo8 w/ 10.5 hotside

And with that I am making 50whp peak more than you on the same dyno. But the real intersting part is here:

6500 rpm +70whp
7000 rpm +90whp
7500 rpm +70whp

Trust me, it's a hard decision to give up on something you think should work. Been down that road . . .

 

You have a larger turbo, of course you make more HP up top. I really don't think you can put that difference on the cams. The EVO IX turbo seems to make about 30-40 more peak and hold up top considerably better then the VIII turbo as well.

I believe the comp 280s were designed by FP as a first generation to their current cams. From talking to Robert, the 280+ cams sound very similar to their current FP4R cams, which performed pretty well in AMS's test.

 

These are all great entries to help solve the possibilities with your stock setup for peak performance. I have been doing the same but with the help of the IX turbo. Believe it.. The IX turbo from $400-500 is a great purchase for your purpose. I hope to make near 450 by the time I'm done. I have every bolt on possible and tuned with Evoscan and ECUFlash. I did buy the Tactrix Boost solenoid to help with the higher Boost. It helped out tremendously. I am boosting to 28-29 lbs and dropping to 23-24 solid throughout. Good luck and I love to see someone else doing the same.

 

absolutely agree with the theory of more idc.
doesn't the stock ecu ignore lambda readings from the narrow band lambda sensor once over a certain boost level /load / tps?
so how could idc be changed to align afr's ?

 

Alright, so I've got a few calls for a cone filter, a few for porting, one for water injection, and one to put smaller cams in...

Anyone else? How about this, has anyone tried to preload the wastegate actuator all the way in? Did you gain anything? Huge torque peak?