Hi, i just put on all these goodies and was wondering what my estimated WHP gains will be after a Dyno/ECU reflash?

DNP Racing o2 housing
Megan Racing 3" Downpipe
Helix 3" Test Pipe
Helix 3" Cat Back Exhaust
Hallman MBC set to 20psi
K&N Typhoon Intake

Also one other note:

I was driving on I-95 last weekend, when i floored the throttle, and my car made like a hard stutter, and my SES light came on, if anyone can tell me what it was, please leave a reply to this as well.

 

Probally your test pipe since you aren't running a cat anymore, I got an o2 simulator with mine from buschur racing and it took the CEL light off. Search around on the boards and you can find sims to install to get rid of it.

 

how do you like the helix.... oh and the reflash.. that can vary all differently from company... ( i have no mods remind you).. but if i were you i'd go with vishnu.. they seem to have their **** together... just do some lookin around

 

I'd say with tuning you'll probably be looking at around a 50hp gain over stock. Don't ask what that equates to in raw #'s that you'd see on a dyno otherwise everyone will argue about what type of dyno you use. Just be happy with your extra power and know you gained close to 50hp with good tuning. Doesn't matter what numbers you get, it's the difference between the two and the area under the curve.

That stutter and SES light you encountered could be the ECU detecting knock and pulling timing. I'd suspect with the freed up exhaust running higher boost that your intake is leaning out your mixture pretty well. Although the factory ECu runs pig rich, intakes have been known to cause leaning out of the mixture on EVO's.

 

I agree... i think it's your intake... a lot of ppl seem to have issues with them moreso than other's on this board and other's i met in person with, and some put that "sock" over the filter and it still had that issue... I also think Al commented on that intake once before too... I don't think it's your test pipe as that has that built in ses fix... So if it's the intake, a Flash should remedy the situation...

 

50WHP gain only after the reflash with my mods? thats a bit low isnt it? a friend of mine with the same mods but different name brand has a total of 300 WHP after reflash.

 

A test pipe CEL is a soft cell. The car wouldn't stutter from low voltage from the rear O2.

 

Zero,

I highly reccomend you get a Walbro pump for safety. Do a search on it, and you will see that the car with opened up 3" exhaust starves for gas in the higher rpm ranges.

 

sounds like fuel cut

 

It was probably your K&N Typhoon intake. Get rid of that thing and go with the HKS RS or the K&N drop-in with the stock box.

 

that is a po 0300 code cel. random misfire. there is a reflash avaliable at your dealer get your ecu reflashed at mitsu before getting reflashed for power. trust me

 

yea right, if they see the MBC on my car, warranty voided on the spot. it hasnt happened anymore, and i do thing its a fuel cut. So ill be getting the walbro pump tomorrow.

 

Isn't SES for the airbags??? If it was because of a test pipe, CEL would come on.

 

Hi I get the intermittent stutter at ~3500 or ~4500 at WOT in the upper gears (3-5).

I do not get a CEL though, so I don't think I have the misfire. It was worse in the winter, so I think it's also fuel cut in my case. I do have the Walbro pump and it didn't eliminate the problem.

FB

 

I'd guess ~280-290WHP.

Also, like others have suggested, I would look into a new fuel pump and I'd do injectors at the same time. I've got a Buschur Stage 3 and I'm seeing injector duty cycles at 100% in the upper RPMs. It still running plenty safe enough AFR but it's not ideal. I have no room to crank the boost when I'm running 100 octane.