i was wondering if by putting on an exhaust with custom piping [prolly 2.5] is ok for the engine? my girl [she has the lancer] said that it would be bad and that she should get a short ram intake first before putting it on. she thinks this becuz there's more air leaving the engine than going in. i dunno. any info would be great.
thanks

 

u cant hurt the engine with an exhaust

 

personally i'd get both. u can start off with a simple cone filter. can find those on ebay for like 20 dollars or something. not a big punch in the wallet anyways...

 

You'll be fine to go with either. You are on the right track with what ever you do first. Remember a good rule of thumb is to work your way towards the engine first. So you are doing a full cat-back, correct me if I am wrong anyone, but I believe you may lose a little low end torque but will gain it in the top end. So by all means do it!!

 

Without an intake you may lose some low end torque. I think it's good advice to put the intake and exhaust on together though so you won't have any power loss, but that's just me. I don't know your money situation either.

 

Enough speculation, dammit. Just kidding.

I did my exhaust first, and there was noticable torque loss. And I only went 2.25". This is a point of contention, but, I think that 2.5" will be an evern more drastic torque loss than what I experienced.

Another problem you will probably face is that the already foul-happy stock sparkies will foul only that much faster due to a lack of sufficient backpressure (or so I've heard. I'm scared to take my plugs out... blacker than black, I'm sure).

 

intake first then exhaust
its simple physics:
with an exhaust expect ..
same air in same air out, just faster way out
with an intake expect...
more air in more air out, but out slowly
intake with exhauste
more air in, more air out faster

dunno if that makes sense but i tried

 

I think he understands the basic concepts, but, the question he had was what are the results going to be with me doing this first.

As such, I said you'll notice a bit less off the line torque, but, you'll notice a bit more speed through the top of the powerband, and in highway driving.

 

Well if he can afford a catback, I would just save the extra pennies for an intake and then do it all at once. What Hardcore tuner is saying sounds good. I am just thinking F/I because opening up your exhaust does help, but then again I dont really want any back pressure in my set up. But then again maybe he cant afford the intake and just wants an exhaust now you guys got me all confused!!! HEHEHE!!!!!

 

Well, here's the thing... there is a necessary amount of backpressure. Too little, and you lose torque and off the line power. Good example, a local shop that I know of is doing a "project OZ", and the first thing they did was custom fab a CAI (before the Injen was out), and then add on a catback. The catback, however, was sized at 2.75". Way way too large for a NA 2.0L engine. The absolute largest you can go (I say that it's too large, but, who am I) is 2.5" by most accounts before you really start sacrificing torque. They had to slap on a tunable muffler in order to be able to get off the line at all, however, they said the noticed longer rev durations (see: speed increasing in upper RPMs at a higher rate than the RPMs are climbing; rev duration does NOT mean a higher redline), and really "flew" on the highway.

Now, this is pretty much only a concern for NA vehicles, which may be why you're confused. With a Turbo application, you can pretty much go to whatever size you want (exaggeration) without worrying about torque loss since there is ALOT of air flow into the engine. Without forced induction, there is a severe line as to how much air can get into the engine. Go over, and you lose torque, and off the line power. Go below, and your engine won't be breathing enough. I went 2.25" because that's a fairly conservative number (pretty much in the middle) and because if I ever decide to get a header, then, I won't have to worry near as much as I would be with a 2.5".

 

i agree you do lose some off the line torque. however, if you are worried about racing...once you get into the upper power band in first gear, your car stays in this band through shifting into each successive gear. you will notice more power in this band, and therefor faster times. how much faster? not much, expect 3-5hp peak. the only downside to putting on exhaust first is the torque in low rpm that you lose, but if you are good at launching this may not be much of a problem anyways. that's the performance side. if you're installing an exhaust system for mostly the sound of it....i wouldn't be too worried about performance loss at low rpms.

so basically the answer is NO it will not be "bad".

 

aiite guys, ive all been a great help. im gonna tell her to go for the 2.25 piping instead becuz it sounds more logical. she already has the exhaust, it just needs the piping and to be welded on. she can afford an intake right now, but she just doesnt want to buy a short ram and then see a CAI come out later. as for those intakes they offer on ebay, u just cant trust em. ill link her to this thread and see what she thinks. also, do u think she should get the test pipe?
thanks for ur help again.

 

If her car is a 5 speed there are a few options for CAI's out there already. I'm guessing it's not a manual trans though.

 

yea its an auto

 

Don't bother with a CAI. The effective difference is barely noticable. I've run both and I'm currently running a short ram. I'm totally satisfied with it and I'm lacking the large filter that RMR offers and the velocity stack that RRM offers.

EDIT: A CAI on the auto would require more or custom bends in the piping and/or narrower piping, both of which would make it less effective anyway. Unless it's for looks or maybe 1-2whp it really should be far more cost effective to just get a short ram.