Autometer does NOT equal "real gauge". That's funny...

-E

 

Best advice in this thread. Take it to TTP and have them checkout the car and the tune. It's not worth taking a chance on.

Autometer FTL.

l8r)

 

The boost tapers because exhaust backpressure in the turbine housing forces the internal wastegate flap open. The spring pressure on the actuator is not strong enough to hold it open.

Larger turbos don't really have the problem because they use larger turbine housings therefore less back pressure. Problem with larger turbo is the boost threshold is greater.

I tried getting the stock 9 turbo to taper less by installing an uprated actuator on my friends Evo 6 which runs 11.5. We did datalogs before and after and the uprated actuator could only hold boost just a tiny bit better. Not a big difference at all. It still tapered.

Some say you can do ECU based boost control which I think is closed loop and this helps taper. I'm not so sure this I think would probably help a bit although I'm not sure how much.

As for spiking 1.8 bar, I'd take your car to a reputable shop and have it confirmed the car is indeed mapped to run that boost level safely.

 

Well, I took the car out today to run some errands & had my gf with me & she watched the gauge & it may have spiked to 1.6 bar @ the most. When I check the gauge initially, it was EARLY in the a.m. & therefore alot cooler outside. Apparently this must make a difference (Duh...colder air = more dense air ). As for the car having a tune already...how would I know? Like I said, I'd bet $$$ that the car doesn't have a cat & it's not throwing any codes...does that mean it was probably tuned? It was owned by a Trinidadian fellow by the name of Deryk in Miami/Hollywood area. I was told he used to be on the forum under the name of Dr. Evo or Dr Evo or something like that.

 

You can either:

a.) go over into the ECUflash section, educate yourself on how to extract the ROM from your ECU and post it for everyone to look at

OR

b.) Take it to TTP, who in about 5 minutes can tell you whether you have a tune on the car and if it's any good.

l8r)

 

lol @ autometer a "real" boost gauge.

but yes, it's been said. either turn the boost down or verify somewhere that it was tuned for that amount.

the joy of buying a used evo, huh?

 

put your car in first gear on a level surface and rev it. I believe the factory 2 step is set to 5000rpm(it is on an 05) so if its anything higher then its been tuned

 

Heeltoe...funny thing you said that! I remembered that the IX had a 2 step built in @ 5k rpm & decided to try it when I took my friend for a ride earlier in the evening. The car must've been tuned! The 2 step is set @ 5500rpm & the car definitely has an offroad pipe bolted in & it's not throwing codes. Why do you guys say Autometer isn't a real boost gauge? I thought they made quality stuff. Am I wrong? Sure hope not...

 

+1 Turbo characteristics make this happen. Many factors do it. Sometimes a stronger WGA can help hold it longer, but what happens often with smaller turbos is the engine starts to out-flow the turbo, and it can no longer hold that much boost. On a neon srt4, rt-ernie welded the WG shut, so it was ALL going through the turbo, and it still only made ~ 30 psi up top.

--mark

 

Stop posting these same questions over and over, then go outside, turn your boost down, and make an appointment with a local tuner. The more you keep boosting it at such high boost levels, the more likely you are to damage something.