Hey guys,

I have a bit of a dilemma. I have been doing research to figure out which direction I want to take in terms of future mods. Right now, I have it narrowed down to an exhaust system and/or HFC's.

My concern is that by adding an exhaust, I am looking into a Greddy EVO2 single pipe (I'm on a budget), the car will lean out and the ECU will flip resulting in power loss or little to no gains. I don't want to spend hundreds of dollars to have my car feel slower after an exhaust mod. I also don't want to buy the Greddy and then have to pay for a TS or Osiris flash. Has anyone noticed power loss from the single pipe Greddy EVO2? I don't believe this exhaust comes with a Y-pipe, so there would still be some back pressure. Will I gain more power by replacing the stock y-pipe when I add the exhaust, or is that a waste of money? If I reflash, will the y-pipe and exhaust help me gain more power than just the EVO2 alone?

Also, some people have suggested keeping the stock exhaust, but just adding HFC's. They say that I will gain mid-range TQ without losing power since I'll still have the factory exhaust (minus the mid-pipe). Is this is viable alternative, or am I basically cornered into paying for a reflash after getting an exhaust or HFC's?


All in all, I've done a bunch of research, and I am still confused. I have searched, and ANY feedback is much appreciated.

 

+1 also......i'm looking into the single left side exhuast and wanna know the same thing

 

come on guys, it seems like everywhere i post i can't get an answer.

 

i think u'll be fine with just a catback.....it seems like the more exhuast you do, the less back pressure u get , and then u start to loose power

....you wont even be able to really tell the difference

i removed my resonator on the stock exhuast only to get more rasp and not like it, and then i got the strup test pipes which give a lot better flow but now might be loosing power or not even gaining anything because i dont have much backpressure........unless i was turbo , so i'm just gonna get a catback like nismo or top speed that isnt a TRUE DUAL and still gives me some back pressure


my friend has a yellow lexus is300 and has a full exhuast from header to downpipe, to full catback and actually lost power and it sounds good but actually lags more at the low end now

....i feel my car lags a bit but seems to pick up at higher end....i think you should leave it stock unless your doing motor work . ie. tuning, a/f , and manifold work


.....u should be fine and not loose anything with just a catback, but you wont gain 20whp like the ad's say on most sites unless you have a highly modified engine

for ex. on my old maxima, injen said 5-11 hp for just a intake when really on the dyno i only made about 11hp from a full exhuast and intake and other work

 

if u want a stock sound and want to save money, just swap out the ypipe to get better flow....ur car will adjust to it and most places will laugh or ask u why u want a tune or reflash just for a simple cat back. only for more work and engine is it really needed......

....on my old maxima i still read stoich and didnt lean out at all....but it never hurts to get it checked out and personally....I'd rather run a slight richer than lean....never hurts to smell some more gas burning lol than not enough burning

 

Thanks for the advice.

We'll see what happens, but I'll try out the exhaust, and then go dyno to check out the a/f ratios. If I feel like wasting money, I'll just install an Innovate LC-1 or soemthing, so I can constantly keep track of the a/f.

I think I should be alright with a y-pipe back like the Greddy EVO2.