People keep talkin about CA **** gas, while here in an area of a quarter million and an oil refinery 15 miles away, plus wells every 100 feet, all the Exxon's, Chevrons, etc sell is 91 octane crap =/

My Evo is going to be expensive to fill up if I have to put a couple gallons of Toluene just to even out the crap pump octane.

 

Yup yup... except mine goes down to 17psi by 7K rpm

Hallman evolution RX mbc

 

does anyone know the answer to my question???

 

From what I have gathered, the computer in our cars is actually quite stupid. There is simply a field in the code that says open wastegate after 2.8 seconds of full boost. What the Vishnu and Dynoflash guys do is up that time to infinity, which gets rid of the taper. The MBC tapers that the others are talking about occur because of the mechanical limits of the turbo and intake system, not due to electronics.

 

Well, unless any of you guys are engineers I'm more inclined to believe the person who is qualified to do repair work on our cars.

 

I don't have a boost gauge on my 7, but a jdm E8 i drove the other day went up to 1.3 kg/cm2 then backed off to 1.1 near redline. The E6 I had never held boost all the way to redline either (that was a euro spec).

 

Actually, I AM an engineer, thanks.

 

A mechanic and an engineer are two very different things!

No not at all. I was one of the original posters on that thread. The clamp refers to the hose clamp between the upper intercooler pipe and the pressure side of the blow off valve. It was loose on my car, I knew because I would SUDDENLY lose boost occasionally, especially on colder days. Tightening the clamp made the problem go away. As far as boost taper is concerned, our cars are supposed to do that, just like Shuusuke Inagaki intended. Now he's an engineer.

 

You're close to starting a vendor discussion here, just be careful we don't start flamin', etc. You may be right about how those vendors get by the boost taper issue. Theirs is not the only approach. I encourage you to do the homework and find out how this, as well as other ECU changes, are handled by the vendors to make an informed decision about their methodologies and approaches. All flashes are not equal, and some use more "engineering" and depth of technical thought than others... just my $.02...

 

SuperHatch> You seem to know about the waste gate and actuator stuff well. Could you tell me why I am getting only 1.3bar boost even when my EBC is already set to max? Some said I need to upgrade the spring because it is setup only for 0.7bar. What is your opinion?

 

The only way the spring on your wastegate is going have an effect on your maximum boost level is if the flow gets so restricted in your turbine housing that the exhaust gas pressure pre-turbine is high enough to push open your wastegate. The softer the spring on your wastegate, the easier this is going to happen.

However, I think you would be boosting much more than 1.3 bar before this would happen (On a stock Evo turbo/wastegate setup). I would check the routing of your EBC connections. Depending where you installed your EBC solenoid and if you left the factory BCS connected, the computer could still be pulling boost on you when you're trying to add more with your EBC.

Knowing more specifics about your setup would make it easier to diagnose rather than using pure speculation.

- Steve

 

Oh wow. I agree with the earlier guy. What you have there was an assumption made by Al. That 2.8 field is actually HEX, which means the value is actually 40 in decimal. Now, I guess it doesn't matter because all he does is open that field to an infinitely large value, but after seeing Al make a mistake like that I wouldn't trust him flashing my ECU... it just so happens that a mistake in this field doesn't make a difference, but heh.

I went with the Vishnu XFlash instead. I feel much more comfortable talking with the Vishnu guys - they're technical, and they know their stuff, and they do it for a living.

 

Vishnu's XFlash doesn't really regulate boost, so to speak. It enhances the stock curve to a couple of psi higher, however. It does this by leaving the solenoid out of the loop, as the other guy mentioned his service rep suggested. With the XFlash, you get an ECU flash, and a straight connector to connect the two lines going to the boost solenoid.

 

Just so some of you guys know, you can't really control boost through an ECU reflash. What you can do is enhance the stock boost curve. Good ECU management units like the XEDE and UTEC will allow you to map boost as a function of airflow or RPM, which gives you control you can't find anywhere else. Stand alone EBC's or MBC's can't do anything close to that, with the exception of Apexi's AVC-R. Stand alone BC's are usually stuck to holding a constant value all the way to redline.

 

What is it with you Vishnu fanboys? Why do you feel the need to rubbish Al every chance you get? How is your post even relevant to the point at hand? There are hundreds of satisfied customers of Dyno Flash so he must be doing something right. Al's customer service is also second to none. Also, i am totally unaware of a single car running the Dyno Flash that has had any sort of mechanical problems related to said flash. If you are going to make accusations then at least back them up with proof.