my test pipes have 2.5" inlet and outlet goin to the nismo cat back. As long as I ease on the throttle and dont go wot between 3k-4.5k the car sounds AMAZING!! once you go wot in that area it sounds like a honda for a bit

 

2.25" -2.5" out, 2.5" - 3" y pipe and 3" exhaust. the cutout is right behind the y pipe, the 3" exhaust part. but i just put my stock cats back on last night and sure enoghf its alot faster and sounds great again. ps i did notice a small loss in the 6k and up range but overall its a lot better the rest of the rpm range.

 

My test pipes ripped on the top end.

 

I love my test pipes, not rasp at all

 

Mine rasped between 2800-and 3800 but I think its because I have headers with my SSV. My Z was so much louder than 350zDCalb car and he has 3" exhaust with straight pipes all the way through.

 

I'm having second thoughts about installing my Helix TP's. I'll probably just give it a shot and if it's that bad I'll just throw my RT's back on.

 

^^ Ignorant statement



uh... unless you got 4" test pipes, you probably just need tuning. ever hear of getting a dyno with air/fuel measurement??

 

ya but to go and pay $800 for a good piggy back computer and then $300-400 for tuning just to get small gains and have my car sound like @ss, not worth it in my book. and i know i could change my exhaust but then it would be $650, $800,$300-400 for the set up i would want, just so i could keep my pipes, um no. i may get a comp one day but its not in my buget or a priority for me right now.

 

Not surprising at all.

People fail to realize that loosing midrange power is extremely deterimental to overall 1/4 mile performance seeing that the midrange (4200-5800rpms) is where the car spends most of it's time accelerating at WOT. Take away 10whp/wtq in the midrange and add 20whp in the topend (5800-6600rpms) will not make you faster. I can guarantee you that. Calculate out the average power across the powerband and you'll see the truth.

 

When you up shift at redline you're not going below 5k rpms. Wanna know where you stay at on an upshift? Topend. Your car will only see midrange power in 1st gear at the track.

I love my test pipes, they made the biggest difference of all my mods. Yeah they rasp, but so what. I've actually gotten compliments on the way my exhaust sounds from people I've raced on the street

 

1st gear is extremely important as is 2nd gear. The first 100' feet of a race if the most important. Here's a great example. On my 96 VQ30 Maxima 5MT, I added a JDM variable intake manifold which greatly increased power above 5600rpms where the stock non-variable intake manifold would loose power. I went from making a peak 183whp@5600rpms to making 189whp@6100rpms. Instread of power dropping off like an anvil above 6000rpms (140whp@6600rpms), the power stayed above 185whp all the way to the 6600rpm redline. From 5800-6600rpms, the intake maniold gained my car anywhere from 15whp all the way to a whopping 48whp. The problem was the intake manifold lost about 10whp from 3500-5800rpms over the stock intake manifold. While driving around town, it was surprising just how much that lack of midrange punch hurt the peppiness of the car; however, I thought for certain the gain in the topend would make up for the loss of midrange. I was wrong. The car ran the same times which was 14.6-14.7@96mph on three different track days and all under similiar conditions, same track, and same 60 foots. My 1/8 miles were slower because of the reduce midrange power, but my car was faster in the last 1/8 mile which made up the difference, but in the end it was a wash. I was completely perplexed as were other Maxima owners that were seeing the exact same results. How could you gain 15-50whp from 5800-6600rpms and be slower? The reason was the calculated average powerband (the rpms you accelerate through in the 1/4 mile) was bascially the same. Overall, the car gained a mere 5whp which wasn't enough to make any difference in performance.

In order to correct the problem, I had to add a $600 JWT ECU which restored the midrange power loss and extended the rev limiter to 7000rpms. The additional power and more importantly the extended limiter, allowed me to push the powerband up 400rpms which resulted in more ideal shifts. My car went from running 14.6s@96mph to running 14.3s@99mph with just the ECU. The ECU and the new powerband (5000-7000rpms vs 4800-6300rpms), the powerband was ~35whp stronger.

I know exactly what everyone is talking about with the low to midrange power loss and I know exactly what it does to the performance of the car. If you can honestly feel the loose, you can be assured you're slower in the 1/4 mile. The problem is only about 5-10% of the people on this site actually test their cars on the strip to see if the mods work. Instead they choose to use their butt dynos and additional exhaust to determine their gains. It appears to me that you're one of these people that chooses to go by butt dynos and street racing instread of actually testing under the lights. I got news for ya, street racing is an absolutely horrible way to determine the performance of your car.

The power of suggestion is a very powerful thing.

 

I trust the butt dyno as much as you do, but I'd be lying to myself if said I didn't notice a gain with the test pipes. I go to the track when I can, but haven't been in a while. I ran a best of 13.79@100mph, 2.02 60' with just a pop charger and my 19's, with the full sound system intact. So no I'm not one of "these" people that uses butt dynos and "street racing" to test out new mods and claim my conclusions to be concrete.

 

i do agree with the butt dyno not being best but at the same time dynos aren't always accurate either, especially with a 5-10 hp difference. and by the way i never street race, in fact i highly disaprove of it. anyways lots of things u can't use ur butt dyno for because the mods may not make a big enoghf of a difference to feel. and the other factor is the persons personallity, whether there galible or not. if they want to feel the gain, or if it make a different sound they'll feel the gain whether it did any good or not. but i am a very very hard critic of my car, and push the car to its limits "accelerating 0-60, not top speed or reckless" basically ever day. because of this i can tell differences very well. if it was a weekend driver it would be very very hard to tell any difference. not all of my mods were good, i hated my test pipes. but the exhaust did indeed make a good difference, not a little, but a good difference. and what makes me so sure of this is because when i switched back to stock for a week noticed the big drop in top end performance.

 

as far as my test pipes they my do good on some 350z's but just not on mine, everone here's car it slighty to majorally differenet and depending on what mods u have makes a world of difference. i'm just stateing that with my set up it sucked, lol

 

so tell me, why do you mod your car N/A if you don't want to spend money for minimal gains?

and instead of 800 for piggyback computer + 300 for tuning, you can get a technosquare reflash

I honestly don't care, if you want to take off your test pipes based on your butt dyno, go for it

plus...
$50-70 to find out what is going on with your air/fuel and HP curves, sounds like a worthwhile investment