No apology needed. I just seem to remember them stating, this was a pre production car and that the specs would likely change. Hence to me that sounds like a ringer to create hype, until at least the production model came out. But, like you said, I'd like to see a production SRT on the dyno.

 

I was digging around and came across an issue of SCC:
Underrated hp/tq? Me likey the idea.

 

I'll second that.

 

I read somewhere (can't find the rag now) that the reason the SRT-4 put down more than the rated 215bhp, was because the engineers tuned it to put out 215bhp with a worse case scenario in mind. Meaning crappy gas, high intake temps. And they also said that the production versions would be off by 5% hp at the most when compared to that pre-prouction car.

 

The SRT-4 is tuned to a 250lb-ft internal map, it calculates air density looks at the stored map and choses the appropiate boost to hit the 250lb-ft goal. As far as I know it is the only car to regulate boost this way. Also remember it is a 2.4l engine so it makes the turbo spool very quick, it is a pretty impressive engine but it lacks the ultimate proven power potential of the

The SRT-4 is definitely underrated from the factory

 

This ignorance is why we in North America had to wait 8 generations of Evos before we got one. Mitsubishi was worried we wouldn't undrstand the Evo and to a great degree they were right. I certainly hope shiv hasn't left the building.

 

DSMs do not control boost via the ECU under normal circumstances. They are not like Audis and VWs. They only reduce boost if they detect a long term octane drop. Otherwise, the boost controller is a simple bleeder and mechanical wastegate setup.

You can replace this coarse boost control with an electronic controller or a ball/spring controller that will give you better adjustability.

 

He didn't explain anything. He said that the 1bar MAP sensor is useless on a car that runs 2bar of boost, and that it run. It is not a MAP sensor. It is a MDP sensor, Manifold Differential Pressure. It is not there to measure boost. It is there to measure vacuum. It can sense when the EGR valve opens. If it doesn't open when the ECU tells it to open, the ECU (OBDII) then turns on the check engine light. This sort of thing has been well documented in the DSM world for years now.

What I was getting at with that post is that people, even Shiv, a respected tuner are fallible. I don't accept what anyone says as fact straight out, no matter who they are. I'm an engineer. I analyze data before I accept it as fact. I don't accept that a dyno dynamics dyno with X load ramp-up setting is any more accurate at getting an absolute power number than a dynojet (2WD or AWD). I do accept that an engine dyno gets an absolute power number, however. What is important is that the results are repeatable on the same dyno.

 

Agreed. That's why I find Shiv's results very valid. He's one of the only tuners to come on this forum and display all this testing data from numerous Evo 8 dynos and various other AWD cars.

So far, Shiv has shown us that the US Evo makes only 180whp on his dyno with 91 octane, while increasing that to ~93 brought about another ~9-10 whp to bring it to 190 whp. I think that was pretty important information for those in CA as they will have to rely on 91 octane and if it wasn't for Shiv, we may not have known this for some time.

Also, based on the SCC dyno results of the press car, there's something different in it vs the US Evo and I'd like to know what that is (Also the point of Shiv's post). I hope SCC looks into it for us.

I really hope Shiv continues to share his findings and test data with all of us because, through all the debates/etc, we can all still learn a few things from all of it

Mark

 

How on earth did he prove it?

 

Obviously a piggyback isn't ideal. It does cause some relatively minor side-affects. However, all I am purporting is that a piggyback that is user-adjustable is a hundred times more ideal than a chip that you plug in. To get the most power out of these cars requires tuning for the current conditions. I'll give you an example.

For day to day driving, I have a state of tune that isn't too agressive. I run 18psi. I leave the mixture fairly rich, and I run anotehr 3 degrees of timing on top of the stock ECU's map. This gives me little to no knock.

For autocrossing, I look at the conditions of the course. If it is wet, I will turn the boost down a bit from my street setting. No point in just spinning. I'll sometimes adjust the fuel and timing if the engine gets too hot after a run. Sometimes I'll throw in a little leaded race fuel when it is dry and I can get the power down, and turn up the boost, and tune a bit more agressively.

For drag racing, which is a relatively short time at WOT, I'll throw in C16 117 Motor octane leaded race fuel. I turn up the boost to around 23psi. I'll lean the engine out a ton to account for the change in specific gravity of the fuel. And I'll advance the timing another 3 or 4 degrees on top of my street settings. I always ramp up timing. Big changes in timing can lead to knock. Then on every successive run, I datalog and look at the knock, timing, fuel, etc... If I get knock, I richen up that particular RPM, or decrease the timing.

That degree of adjustability is what a piggyback or stand-alone can get you. And 90% of DSM owners tune the exact same way I do. I tune for the current conditions.

You can't get that degree of adjustability from a "chip." Instead, if you buy a chip, you will have to get your car re-tuned after every part addition. Get larger injectors and you're in a world of hurt until you can get to the chip tuner to get another chip burnt.

Me? I just adjust the fuel settings. Piece of cake, and the car runs great.

Can you see the benefit of having user adjustability? Yes, you have to learn what your car likes. You have to learn about combustion. You can't get maximum power out of your vehicle in all conditions (if you want to) by taking your car to a guy who burns an EPROM for you.

In the real world, those variances in temperature or humidity or air pressure DO CHANGE the power output of a vehicle! Just because your dyno has perfect conditions doesn't mean taht the real world will follow those perfect conditions, and you will get the same power that you dynoed.

So far, what has Shiv taught you? Has he taught you how to tune your own car? No, he sells a service that will tune your car to one particular setting for a relatively high price.

Shiv talks about replicating real world circumstances with the load ramp-up on his dyno. I don't have to adjust the load ramp-up on my vehicle when I drag race. I don't have to replicate real world circumstances...I live and drive in the real world.

The power or torque you get out of a particular part isn't a constant. It does vary with the weather and the conditions you are driving in. Hell, with a turbocharged car, power output also depends on the driver. Shift badly, and your torque curve in the next gear is going to completely suck.

 

Not all of us want to drag race though. Many of us attend track events, autox etc. Each application has its own needs and a dyno provides a great tool to see what the torque curve looks like and where improvements were made and could be made. Final adjustments can always be made at the track.

Mark

 

Now I got ya. It reads differently after you rephrased. I understand where you're coming from now.

 

Final adjustments can't be made at the track if you have no way to adjust the "chip" you bought for your car. That was my point. Dyno away, but adjustability is key, and it isn't something you can get from a standard chip.

Now, get something like DSMLink ( www.dsmlink.com ), and you get something that is actually worthwhile. This is what I use. It allows the user to adjust his own fuel and timing INSIDE the ECU in real time. It also gives you a stutterbox and allows you to datalog at a very high data rate. I have no idea if such a program exists for the Evo yet, however.