no gain.. so dont expect one. take this example into consideration.

..in : INTAKE FILTER/pipe > MAS > TB > INTAKE MANIFOLD
out : EXHAUST MANIFOLD > DOWN PIPE > CAT(S) > MUFFLER
rough example... i know

if you upgrade anyone of these without the rest you pretty much wont notice any performance gains. the gain will be so minimal that you wont notice and i doubt you will shave any timeoff your 1/4. it may look nice to have a new intake, or a new header, or a new muffler but unless you have these installed collectively dont expect to smoke the tires in 2nd. (note: not saying that if you did have all parts you can smoke the tires in 2nd)

I say if you are gonna upgrade your breathing, work with the most constrictive of pieces to the least constrictive. coughCATcough

anyone else agree?

 

I tend to disagree on that. By putting a new intake or header on your car alone, you will notice some performance gain. But if you do put a new intake, MAS, TB, header, cats, and muffler together the performance increase will be much greater than one or two of them without the rest. I have the Injen CAI w/ heat shield and the absolutely terrible RMR exhaust and I did notice some preformance gain with the intake. Not that I'm smoking the tires in second or anything but it was worth the investment.

 

Shmoo, my guess on the gain from your header would be somewhere from 3-8 hp.

 

I agree on one point... the fact that the time won't be dropping off of the quarter.

But, I've come to realize, and I hope other owners have as well, that the Lancer is not a quarter mile car. This car would be more suited to autocross (now I KNOW b is gonna come down on me for that), and as a good daily driver. That being said, I disagree on the rest of the post. This car gets good power gains from simple bolt ons, as has been published on at least one occasion. Not great power gains, but, noticeable. Plus, you don't HAVE to have all of them to get a noticeable gain, but, you would need all of them to have the maximum for NA power gains.

Now, i would recommend getting offsetting mods. For instance, I got my exhaust, and had some backpressure problems because I had that restrictive airbox. I added the Injen, and now, it's evened out, and there is a very noticable and favorable change. Personally, I would do the TB before the header, but, to each their own.

As for recommending changing the cat(s), I wouldn't even mess with the second one unless you're trying to go hardcore, and really, I don't see the benefit of it. You'll get HP gains, sure, but, the sound I've heard is awful, not to mention risking a fix it ticket. Unless you got a turbo, or enough suspension mods to do some serious autocross, I think it's a waste of cash.

Oh, and one more thing... someone else who had the Header said it eliminated the "AC drag" that we've all experienced. That would almost be worth getting it right now for me... summer in Texas tends to make the Lancer really really sluggish.

 

i have the injen CAI as well, and there is not a gain that i can feel. i dont get thrown in my seat anymore than before and i dont beat cars that i couldnt previously beat without it. i seriously think the gain everyone claims they notice is from the sound that comes from the new intake.

to streetlancer: what if i had the header and no intake? if i added the intake after would that make the AC drag go away? if so then we could simply say that the header alone isnt whats giving you the gain, its the fact the you are getting closer to having the "big picture" painted instead of just a part of it. which is what i was getting at. i can say that cuz i read that same thread you were referencing and that d00d had other mods before he put on the header.

does that clear up my post a little more?

 

So StreetLancer,
You've tried getting rid of the second cat?
What did you do? Try a test pipe and was it reall loud?
I'm debating getting the RRM Test Pipe. I have an Injen too and a custom cat-back. But i don't want to get louder.

 

I'm gonna disagree with you on the Injen CAI thing ez. Though I do have to admit that I did the install at the same time as the TB...I noticed low and mid rev torque gains. I doubt the tb had much to do with it at all running stock exhaust at the time. Those were my first two simultaneous under-hood mods.

 

maybe i'm just wording my thoughts wrong..
you have two things to help you out, thus putting you closer to a complete breathing system upgrade so yeah you are gonna see more power than me. but the original question asked by shmoo was... if i get the header will i notice the gain. so i said no. but if he has a few other mods (which i see he has the injen) then maybe a little tiny one, but nothing to knock your socks off or to go brag to your neighbor about.

i have a question for you Hobie... since the MAS is what determines how much air is being sucked in and then tells the computer how much fuel needs to be thrown in the mix, wouldn't changing one of the constant variables (the TB) that fall behind the MAS make you run lean? i would think the MAS knows how much air the stock TB is gonna let in and it calculates that into the equation of air to fuel. just wondering.

 

Dunno. I'll read up on it when I go home, but I really don't know much that hasn't been answered on the forums already.

Any and all experience/knowledge I might have is from the LF and conversations with people like p and b off the forums. If I can answer it, chances are it's been asked before. Either that or it's on howstuffworks.com. Anywho...I'll look into it once I get outta work in a few minutes.

 

The MAS can learn (I think up to 10% in each direction) to avoid running to lean or rich depending on how much air it's sucking in. By putting in say a newly manufactured TB with a nice big aperture there is a change in the vacuum of air being sucked in is there not? The MAS can count and realize that the air moving is moving in slightly faster or at least with more volume, therefore, it will compensate with time. However, if you're going to be doing a lot of heavy duty mods, then an AFC will come in handy with proper tuning.

 

Or p could answer before I leave...the tb was more of a precursor to other mods moreso than something I expected for power gains....Thanks p.

EDIT: p, my bad.

 

I'm with pjal on this one. The bored throttle body will allow more air into the engine and the MAS sensor will have more air coming through it and compensate by allowing more fuel to pass also.
I think

 

Co'rect. However, it isn't the MAS per se that's going to tell the injectors to squeeze more, but the MAS will yell at the ECU to tell the injectors to start hauling ***. Like I said though, this process is only useful, up to a point.

 

so lets say you have X amount of air coming into your intake pipe per second... the TB only allows for Y per/sec stock. so the MAS is like "ok we have X amount of air coming in but i know the TB will only take on a max of Y p/s so i dont wanna run rich by throwing in too much fuel, ill just put in (X-Y)/9.5 to make the ratio happy" ... but because you have now bored out the TB nothing on you car knows that your TB is actually swallowing X amount of air p/s. im i wrong again? sorry to get off topic with the TB here people, just didnt seem right to start a whole new thread for it. and i also apologize for using such crude examples but thats how i think.

 

The MAS uses fuzzy logic. It's designed to cope with variances in volume of the air being ingested. It's reading how fast the air is being drawn in and how much is being drawn in. It's reading those numbers and realizing: "Hey, there's something different here..." and coping accordingly. It's not basing it's guess on how much the stock compenents are are allowed to flow, but how much air is actually being used. It's thinking "If I'm getting this much air, I need this much fuel", not "If my TB is supposed to flow this much, why am I seeing this much air..." The life of an MAS is drawn up in the volume and quality of air it's sseeing being sucked in, not the ability of its compenents ('cept for the 10% it's allowed to use).