I recently installed my budget y-pipe and really happy with the gain, now I'm undecided on which of these two mods I should do next. I've read and searched thru the org, I have narrowed it down to these two: Unorthodox underdrive pulley $185 (custommaxima.com) and a 2.5 in custom cat-back with hi-flow cat from a local muffler shop (approx. $350-$400)
I just don't know what would better since there are so many different things and mixed opinions said about both these mods.
What do you guys think I should do?

 

If you're tight on money get the UDP first. If you want the sound of exhaust, try removing your muffler. It sounds like you have an aftermarket muffler, but doesn't cost you a cent. Plus it takes about 20 lbs off of your car. Then get that custom exhaust when you have the money.
Just don't get caught by the cops w/o a muffler. I have been running w/o a muffler for months now and like the sound.
I know ppl will flame me for doing it, but don't knock it till you hear/see it for yourself.

 

removing your muffler without attachinig an end-pipe is asking for a ticket from a cop. Removing your muffler PERIOD is asking for a ticket, and is also adding a lot of pollution to the air.

Anyway, cat-back exhaust doesn't add too much on our cars; we need the back-pressure. Some people have gotten b-pipes and 2k max series mufflers, and had better success. I have a UDP, and I like it, but it's not a HUGE gainiing mod either.

 

The muffler has nothing to do with pollution. Unless you mean noise pollution...

 

It stops some particles, as far as I know, from entering the air. Noise pollution isn't that bad without the muffler...I've heard pure straightpipes before on a max and it wasn't THAT loud.

 

im going with an UDP myself, but surely staying away from UR...goign with RMV, and from what i hear, just as good, with SLIGHT less gains (.5 hp), but for about 1/3 of the cost.

 

err no it doesnt... the cat does that... all that taking the muffler off does is **** off people by making us lose our hearing.

 

If your engine is making particles big enough to be stopped by the muffler, then you've got other problems.

And about the back pressure thing. It's not back pressure that is needed, it's high exhaust flow velocity. High flow velocity aids in scavenging the cylinder during the exhaust stroke, due to the inertia of the exhaust gases as they are flowing through the exhaust system. When you go to a larger diameter exhaust you reduce the exhaust flow velocity accordingly, resulting in less efficient scavenging at low-mid rpm and a concimitant loss of low end power. Somewhere back in time somebody mistakenly associated the loss of low end power with reduction in back pressure instead of the loss of flow velocity, and the myth has persisted to this day.

 

Where can I get more info on it and who sells them?? Thanx

 

you can check out www.rvmracing.com, or do a search on the org for RVM UDP ...you can get it for 80 shipped in a group deal here....just check out the group deal forums for more info

 

If mufflers have something to do with polution then my muffler lets more into the air, it is a through and through type muffler. But also a y pipe would cause more polution as would any airflow increasing mod.

 

it does; those pre-cat things on a stocker are there to stop crud form being emmitted into the environment.

I guess I was lied to all these years about the purpose of a muffler.

 

I, too, always thought it was too "muffle" the sound....I dunno

 

Exactly, the muffler is to quiet the exhaust. Now, if you look in a lot of aftermarket mufflers, the internals will look similar to that of a high flow cat, so it may do some as far as pollution, but the purpose of the muffler is to change the sound.

Definition:
Muffler - A device that absorbs noise, especially one used with an internal-combustion engine
courtesy of Dictionary.com - (http://dictionary.reference.com/search?q=Muffler)

I would personally go with the UDP as well. The exhaust is nice, but I think you'll get more out of the UDP for the price.

 

I just installed my UDP last weekend, and there is a difference in the way the car drives. If I were you I would get the UDP before I would get the cat-back system.

Just my two cents.

 

An exhaust on a NA maxima will yield minimum gains. Get the UDP, I think you will notice a more of a difference. If you haven't got a ypipe yet, WHAT ARE YOU WAITING FOR, that is the best bang for the buck mod and should be your first. I recommend you get a budget for $158.xx shipped, its a great deal.

 

Big DITTO to that! Gotta love my Budget Y

 

exhaust = 3hp for $500
UDP = 1hp for $150

you can't go wrong ither way..

 

i'd go with the catback

 

knew you would pipe in eventually!

 

I already have it!

 

Intake and ypipe, which you have, are the best bang for the buck mod you can do. I would not spend 500 on an item that makes 3hp or less and ****es me off when I'm cruising on the highway. Pullies are cool, but are the really worth it. I think it would be wiser investing in a tune up, change fuel filter, run synthetic oil, tranny flush etc.

 

yea, I know that doing schedule maintance makes a world of difference in how the car performs. I think I'm gonna go with a RVM UP cuz its a lot cheaper with just about the same gains as UR UP. I plan on doing both these mod eventually but I figure I might as well get you guys opinion what first. .org knows best(at least majority of the time) and I appreciate everyone for their input.

I've done a search for RVM UP, theres like 10 threads about but they all seems to end without any results on their gains. I know this UP only came out a few months ago but since its been a few months, does anyone have any different or updated results?

 

oh yeah baby