I have a 157 hp 4 cylinder Camry along with my new 2002 Maxima.

I was measuring exhaust size on both and comparing. The smallest pipe I could find on the Camry was 2.125 diameter just aft of the catalytic converter. Most of the exhaust was 2 1/2" diameter. The Maxima is formed down to 1.90 diameter forward of the catalytic converter and also the pipe going into the muffler. Pipes on both ends of the resonator are crushed. My oh my, what was Nissan thinking when designing this exhaust. This 3.5 has just got to improve hp/performance with a full 2 1/2" system all the way back including muffler.

Got to be careful with muffler selection however. Some mufflers like Flowmaster neck down internally on some models. As an example their 3" for the LS1 Camaros necks down to much less then 3" internally. This is why I chose a Hooker muffler for my Camaro.

Come on aftermaket manufacturers, lets get a good exhaust system made for our 2K2's!

 

Where have you been, Larry? I believe if you do a search on the word, "exhaust" in the 5th Gen forum, you will be inundated with information on aftermarket exhausts for 5th Gen Maximas . . . name brand and otherwise.

Regardless of how poorly engineered you consider the OEM exhaust to be, about the most you can expect to gain from a complete 2.5" mandrel-bent catback exhaust system is ~5 hp on 2K/2K1s and ~7 hp on 2K2s.

 

y2kse,

I beg your pardon but show me who has a full 2 1/2" mandrel bent exhaust system for the 2K2 Maxima. Show me the dyno of the 7 hp gain from the full 2 1/2" system.

Apparently you have been somewhere that I have not been.

 

Admittedly I extapolated my data for the 2K2 from published results on the 2K/2K1 and perhaps I'm being just a wee bit generous claiming a ~7hp for the 2K2. Let's do the math, shall we?

We know for a fact that a complete pre-production HKS catback exhaust will produce 5hp to the wheels on a 2K/2K1. We also know that a 2K/2K1 Maxima produces 222 hp and that a 2K2 Maxima produces 255 hp. Working with the equation for ratios, we get the following:

5 : 222 : : x : 255.

Cross-multiplying gives us the equation 222x=5(255). Solving for this equation is as follows:

222x=1275

x=1275/222

x=5.74

So perhaps it would be fairer to say that a complete catback exhaust system on a 2K2 would yield an increase of ~6hp rather than ~7hp. Of course, we'll have to wait for dyno results to prove or disprove the math.

 

emax got 10hp off his catback and i'm gonna dyno again soon hopefully to about that much too. my butt loved the catback too.

 

y2kse,

I did not say "catback". I said "complete" exhaust system. I did not mean to include headers, however, when I said complete so lets assume Y pipe all the way back.

Actually, I'm surprised a catback alone would do anything with that little 1.90 pipe up forward and the crushed pipes on each side of the resonator. 7 hp sounds almost more than I would expect for a catback alone.

 

A Y-pipe on a 2K/2K1 produces a 10-12hp increase to the wheels. Figure another 2-3hp for an aftermarket cat and 5hp for a catback exhaust and it's reasonable to expect about a 17-20hp increase for a "complete" exhaust system. If emax95's results are correct, you might go as high as a 25hp increase on a 2K2.

Quote:

Actually, I'm surprised a catback alone would do anything with that little 1.90 pipe up forward and the crushed pipes on each side of the resonator. 7 hp sounds almost more than I would expect for a catback alone.

Yup. That's why I recommend against purchasing name brand catback exhaust systems. Paying $600-$700 to get a 5-6hp increase is, well,

 

y2kse,

Now we are speaking the same language!

20 hp in my opinion is a pretty nice gain from exhaust work. Granted the price is too much but if some of the manufacturers like Hooker or Walker get involved there will be some quality systems at reasonable prices available.

$700 for a catback. Way too much!

 

I got my Greddy Cat-back for $470 shipped . A did a before and after dyno and with a RT cat and Greddy cat-back I gained 11 FWHP and 9.7 FWTQ.

Now if WSP ever gets my Y-pipe to me I will be dynoing teh gains there too.


Larry I have a question for you. You said this: Now when you say forward of the cat do you mean closer to the engine or closer to the muffler?

 

That is DEFINITELY a reasonable price. Where did you get yours? And can you get more at that price? If you can, you might force me to change my sig!

Quote:

I did a before and after dyno and with a RT cat and Greddy cat-back I gained 11 FWHP and 9.7 FWTQ.

Those are great numbers, but part of that increase has to be attributable to the RT Cat. I wonder how much of the increase is due to the cat and how much is due to the catback?

Quote:

Now if WSP ever gets my Y-pipe to me I will be dynoing teh gains there too.

Good luck!

 

my catback's target price is 450 dollars and will be all SS, mandrel bends, tig welds and full polish..

and i don't think a cat even gives 1hp, test pipe should be good for some.

 

I got it for that price through a group deal here on the org a while back. I got 25% off the list price.

The RT cat does not seem to give any power increases, a guy here tested it on his 2002 and saw no gains.

Steve did you get my PM? I got your message today from a few days ago I don't know how I missed it. Just went 150 MPH, lol..

 

I'll change my sig when you release your catback at $450.00, Steve. BTW, will you be releasing 2K Fed Spec, 2K/2K1 Cali-spec, and 2K2 versions of your catback all at the same time? If not, which will come first and how long after the first one is released will you be releasing the others?

Quote:

and i don't think a cat even gives 1hp

I suspect Random Technology might beg differ with you on that, Steve. There's an easy way to find out, of course. Get a RT cat. Dyno your catback with the OEM cat first. Then dyno it with the RT cat.

 

We both posted at the same time, look up one post and I answered your question.

 

Thanks, emax95. I got it. I edited my previous post based on your post.

If it turns out that a RT cat produces no gains, then I'd suspect NO aftermarket cat will produce any gains. That would be important to know, as RT has dyno plots on their website that show HUGE gains.

When I installed the RT cat on my Max, I felt a minor increase in performance on my butt dyno. But that could just have been wishful thinking on my part!

 

the 2k/2k1 cali spec and the 2k2 are the same exhuast exactly. the 2k fed spec guys will have to do like they do now and get an O2 bung installed at their favorite exhuast shop. as far as i know none of the exhuasts now come with the hole, they all come with none and the few guys that need one get one.

 

Right. I was thinking Y-pipe, not catback.

 

You can get Greddy exhausts for $520 shipped here: http://www.groupbuycenter.com/buy.asp?row_id=5715 That price 20% off with free shipping (48 states).

You mayy need to register a account to see the link. If thats the case go to www.groupbuycenter.com . It's not teh best deal but it's pretty good.



I think a RT cat would give decent gains on a high mileage car or a car with a old dirty cat

 

RT doesn't tell you how old the cats were that they replaced when they ran their dynos. Of course, the only true test would be a new or low mileage OEM cat against a new RT cat. But I doubt that's the methodology they used when they conducted their tests.

 

That's getting into the right range. I can have a 2.5" mandrel-bent exhaust system with a Magnaflow resonator and SS Magnaflow muffler custom-built for about $400.00. That's what makes Steve's upcoming catback so attractive. At $450.00 with SS piping and TIG welding, I think he's got a potential winner on his hands.

Look out, Cattman!

 

Closer to the engine. This is the pipe between the flex section and the cat. It starts out larger but during the forming process they have reduced it down to about 1.90 along the way.

Guys, I bought a Hooker catback for my 98 Camaro for $275.00. It is excellent quality aluminized, mandrel bent 3" with duel tail pipes and chrome plated tips. Certainly a lot more work and tubing required for this catback than would be required for a Maxima. I have had it on my Camaro for almost 4 years and only the chrome tips are rusting.

 

Ok time for me to interject here. I was the person to which Ethan was speaking of (i think). I did a baseline run on my 2002 Maxima and got 200.4hp at the wheels. The thing probably had about 1600 miles on it at the time. (is that new enough?) I went back a few weeks later after I installed the RT cat (NO other mods) and still could only muster up 200 fwhp. Oh yeah I removed the panel filter and guess what I got? (200hp).

Who knows maybe my car is deflicted but thats all I got at the time. The last NA run I did on the dyno I only got 210hp with an intake and UR UDP in place. It's a POS intake though, (bought on ebay) probably hurting me more than helping.

One other thing about the cat. Any of you who are interested in getting the RT for your 2K2 or 2K3, first remove your factory cat and take a really good look at the thing. Then ask yourself if you really think you still need the RT.

 

Hmmmmm. Thanks for the info, SR20DEN. I wonder if the OEM cat for the 2K2 is the same as the OEM cat for the 2K/2K1. If it is, maybe it's time to start thinking about gutting the RT cat . . .

 

You would be just as well off by bolting in a straight pipe. The factory cat and the RT still do flow very well. I still doubt there are any appreciable gains to be had by doing either. But that doesn't mean I haven't considered it.

Thats POS factory gimmick muffler is probably the most restrictive thing on the car.

 

That is good news! I should see good gains when I replace that then

 

Some gimmick!

"[Skyline] models fitted with the M-ATx transmission and the RB25DET engine adopt a newly developed dual tailpipe muffler with exhaust pressure-sensitive control. By lowering the exhaust pressure, this new muffler works to achieve improved engine output together with enhanced quietness as a result of reducing exhaust noise."

Source: http://www.nissan-global.com/GCC/Japan/NEWS/24b6.htm

"An equal-length tuned exhaust with a variable capacity muffler derived from the one on the high performance Nissan Skyline GT-R reduces exhaust system backpressure, adds power and gives one a quieter ride."

Source: http://www.carlist.com/newcars/2002/nissanmaxima.html

"[T]he Z-car will also have continuously variable valve timing, variable induction, and a variable capacity muffler like the Maxima."

Source: http://www.motortrend.com/mar01/nissanz/1.html

Can you buy a better performing muffler than the Nissan variable-capacity muffler? Probably. Can you buy a better performing muffler that's as quiet as the Nissan variable-capacity muffler? No.