OK, please no flames; I've searched for hours now. Maybe I'm just using the wrong terms, but here's what I'm asking:

I saw once someone, in some thread which I cannot now find, say that later model Evo IXs have different firmware and run less boost, perhaps with more taper, than earlier IXs. (I also read that the later IXs may not have a restrictor pill, or pills, in the boost control solenoid vacuum lines.)

If this is true about the lower boost, then I'd love to find out whether my IX is of the earlier, or later generation. (I can look in the door jamb for the date of manufacture, which I do not have in front of me at this moment, or get the VIN.) I would like to know the date or VIN cut-off.

P.S. I do not (yet) have a boost gauge, so I can't tell how much boost I'm running.

Any help here? Thanks.

 

i got a boost gauge for you if you want one

 

Interested; thanks. Selling?

 

The guy who you saw say this was a guy who ran like crap at the drag strip with his stock IX and was convinced that later production IXs had different firmware and lower overall boost, which were responsible for his terrible ETs and MPH. He ran high 13s at 99 and was utterly convinced that it wasn't because he was brand new to racing the Evo. Well, later he went back and was running 13.0-13.1 at ~105 while still completely stock, so needless to say that he changed his "tune" on the whole IX conspiracy theory.

Also, if you don't have a boost gauge yet, I'm not sure why the thought is crossing your mind. All USDM Evos have the same stock boost system with the same lines and same restrictor pills.

 

Thanks, Warr; that's very helpful.

 

From everything I've been told the later IX's had something different with the boost lines (restrictor pill) which made them boost lower. I know for a fact that mine only boosted at about 14-15 psi even with an eflash that raised the limit. Only after having an MBC installed was I able to get full boost. Ask Andy at speed element as he explained the whole thing to me but I don't want to quote him.

 

Flashes don't raise boost - at best, they reduce taper. I haven't seen a IX without restrictor pills, so I'd have to see an example to believe it. Plus, not having a restrictor pill would NOT cause it to boost lower and taper more - it would either cause it to boost uncontrollably high or boost the minimum wastegate pressure, which is 11psi. Some just boost more or less from the factory, but not because of restrictor pills or firmware. Also, IXs tend to taper more than VIIIs due to the extra airflow caused by the MIVEC. The head already outflows the turbo, so when you increase efficiency in the head (MIVEC), you cause even more taper due to the turbo's inability to keep up.

 

thnaks for the info

 

Rod munch,


In addition to what Warrtalon said also remember that a Evo 9 in Colorado Springs (6000 ft) will run less boost than a Evo 9 in New jersey.
A Evo 9 in Tucson at 110 degrees in the summer will run less boost than a car in the east coast in the winter. We can't truly set a specific guideline unless all Evos are tested at the same conditions(temperature,altitude and even same boost gauges).

I suggest a boost gauge like Defi BF Imperial series, you can test and record every single boost reading. A boost gauge is indeed the absolutely first mod that should be purchase for your car. You don't have one yet. Just my thought..

Carlos

 

Thanks. I definitely intend to get a boost gauge. One of these days.

 

Guys, I was the fellow that Warrtalon was refering to, and YES, I FINALLY was able to run a best of 13.09@105.71 Stock, then I installed a Bleeder valve to raise the Boost, and YES, it worked, but a Subsequent visit to the Track was EXACTLYthe same ET & MPH...what was happening is that at anything above 4800 it TAPRED right back to the Stock 16-17 PSI....Aggggg...

So to Remedy THAT I removed the Restictor Pill in the Boost line at the soliniod yesterday, and Retested today, making about 8 or sp passes with the valve opened from 3/8th of the way to 3/4's of the way, and had my Son in the back seat with his eyes GLUED on the Boost gauge..and IT WORKED, to a point, at the 3/8th setting on the bleeder is where it worked the best, at Launch (5000rpm limiter) it spiked to
22PSI and then ONLY settled back to 19PSI through the WHOLE pass..7000rpm in forth...now Interestingly if I had it opened further it would Taper back to 16-17psi (Spiking to 25PSI on launch)..all testing was done with 104 Octane Unleaded!!

Tommorrow I'm headed to Cecil County...THEN we'll REALLY know for sure!!!

 

Why did you change names?