Pit5Bull

I'm looking into replacing my exhaust setup, and I'm looking at the WSP Aluminized y-pipe, Carsound Cat, & b-pipe package for $470, but my question is whether or not to go with the 2.5" or the 2.25" diameter piping. I have an '89 SE 5sp, and I read the article someone posted a link to about custom exhaust systems (I think it was the link to NissanPerformanceMag.com) and I recall that the article suggested that a 3.0L engine should go with the 2.5" piping from the y on back to the muffler.

Is there anyone with a VG with the above-mentioned setup that can offer a brother some advice on which diameter piping to get? BTW - I'm not planning to do more than adding a CAI to the intake/exhaust setup at this time, and no, I'm not ever planning to sell this car, so if I do decide to do more with the engine performance at a later date, I'd like to know that my exhaust will do the job. Also, I'm looking into getting a dual-tipped PowerTech (PT 1011 or 1012) performance mufflers.

Thanks in advance!!!

Matt93SE

iTrader: (44)

go with 2.5". you'll be happy.

Pit5Bull

Thanks Matt for the quick reply! I'll feel the difference without getting the CAI right away, right??? (I have a popcharger now).

Also, do you happen to know what kind of HP gain I'm looking at with the new exhaust setup?

You da man!!!

D-sta

iTrader: (6)

WSP makes good stuff, I have the y-pipe, carsound cat and greddy and I'm very happy. 2.5" is the way to go.

Pit5Bull

You guys are the best!!!

2.5" it is!!!

Rookie_GB007

The Y and 2.5" are top notch. Uou'll be pleased.

lophix

iTrader: (3)

what's the difference in performance b/w the 2.5" and the 2.25"? Dallas had told me that if you were going the way of turbo, 2.5 would be it, else 2.25 was "adequate".

Dark Lord Bunny

iTrader: (5)

2.5" has less restrictions and really is the best to go with on an N/A 3.0L... Turbo setups call for nothing less than 2.5"... 3"+ is common with boost .


But yes, 2.25" is "adequate".... but for a very small price diff if any... just spring for the 2.5". It's better.

Jeff92se

iTrader: (82)

Some notes: Exhaust requirements for turbo and na applications are very different. Boost doesn't like restrictions of ANY type. But na applications depend on exhuast gas velocity to help scavange exhaust from the other ports. So bigger is not always better for na applications. I ran 2.25" because the outlet of the Cattman Y was 2.25" and the cat openings were 2.25" so there was no need in my case to run bigger than 2.25". If you have 2.5" openings on the whole system, then you could run 2.5". I would say 2.5" would be about the upper limit on size.

lophix

iTrader: (3)

kool. thanks for clearing that issue about the need for back pressure up.

Pit5Bull

Since we're on the subject, do you have any suggestions as far as the muffler goes? I've heard that the 'straight through' type is better for performance applications (although there may be emissions issues) - which is another question in and of itself. I've heard that you'll be able to pass CA emissions with a larger y-pipe as long as the car is running at normal operating temperature. Is this true? CA emissions are pretty strict, so I want to be sure that with a new exhaust, I'm not going to have to visit the muffler shop unnecessarily to bolt on the old setup just to pass emissions next year.

Thanks again to all the knowledgeable ones - you guys make being on this board worthwhile.

peace2u

Matt93SE

iTrader: (44)

1. if you plan any more mods other than the exhaust, go with the 2.5"

2. anyone driving an import that asks about power gains when adding exhaust only should be dragged out into the street and shot with rice. (power gains are minimal. a couple)

3. emissions.. drive the bejeezus out of the car to get the cat REALLY hot, and you'll be fine. even people with factory exhausts have problems passing emissions in CA.

4. a muffler will not do squat to the emissions on the car. that's all done from the cat and forward. (the muffler may cause a bit more backpressure in the exhaust, which keeps heat up a bit, but it's a very small difference.)

If your car failed emissions with xxx muffler on it, it will most likely also fail emissions with yyy muffler on it.

Pit5Bull

...but my question was in regards to all this stuff I hear about performance and mufflers. I know that after redoing the exhaust with the 2.5" setup, I'll need to cap it all off with a good muffler, so I wanted to know if the one I'm considering would be a good one to go with (PowerTech 1011 or 1012) or if I should go with something other than a straight-through design. With the 2.5" setup, will there be a problem with not having enough backpressure with a straight-through muffler? Also, will a lack of backpressure decrease the performance of the setup? I'm not all that concerned with the sound anymore - now I want the best performance out of the setup regardless of the sound it makes. I'm not that aggressive a driver, but I like to know that when it's time to go, I can get gone in a hurry. I also may have forgot to mention that I plan on adding a CAI to the mix in the near future as well (probably WSP). If there's anything else I can add that will increase the performance of what I've got going (UDP/Chip/Etc.) I can look that stuff up once the search function is back up. I'd just like to get a ballpark figure on what kind of gains I'll be looking at with just the CAI & Y-pipe setup for now.

I hate asking all these newbie-type questions, but I know you know what you're talking about and I'd hate to screw up good advice by not getting the story completely straight from the sources. Your input (and everyone elses) regarding this topic is greatly appreciated!!!

As always, the .org comes through in the clutch!!!

peace2u

Rookie_GB007

I could scratch 2nd gear with my WSP CAI / WSP Y / catco highflow cat / WSP B-pipe (all 2.5") with my POWER TECH muff. The top end was desireable, and power band moved up the rpm band a little. I had the twin 3" resonated tip. The noise was unbearabel, so I added a DYNOMAX 16"x4.5" resonator after the cat. Still loud, So I took it to another muffler shop. The Tech says to me; "whoever installed the muffler placed it to far under the bumper, all the noise was coming back into the cabin, that is whay it is so loud." So he moved it out 3"s pass the bumper a little. WAY better. Then I decided it was still too loud, so I put my stocker back on, LOL!
I'd say find one of those HKS rear sections from a 5th gen and have it welded in, ar a BIG greddy can.

Pit5Bull

@Rookie,

Thanks for the info. You have the exact same setup I'm looking into getting. When you went back to the stock muffler, did you notice any difference in the gains you felt in the powerband versus the PowerTech muffler? I've read somewhere that the longer the body of the muffler is, the better it muffles the sound coming from the exhaust. I'm thinking that maybe I should go with the muffler that WSP has on their site. I suppose that I really don't want to draw that much attention to my car with the engine growl (still want that 'sleeper' vibe going on, ya-know.) I really like the way that PowerTech muffler looks, but if the thing is as loud as you say it is, then I'll look elsewhere.

Thanks for the input, bro! Have you done any other engine mods yet?

peace2u

Dark Lord Bunny

iTrader: (5)

If you're as serious about performance as you say, then difinitely go with a straight through. It creates the least amount of back pressure, which you want. If you're worried about sound just find one that is the longest you can fit under there. If youre talking about the Magnaflow on WSPs site, thats a good straight throught to go with from what I hear, but if its that OE replacement youre talking about then forget it. It's exactly what they say on the site, an OE replacement which means it will have all that fun back pressure negating (well... not completely.... but I digress) your bigger piping.

Pit5Bull

Thanks D.Lord Bunny!!!

That's the information I was looking for.

crazy4maxima

iTrader: (5)

that is a freaken good price for all that.. is that with shipping.? what muffler are you gonna use?

Pit5Bull

@crazyformaxima...

This is the price indicated on the WSP website. I know this doesn't include shipping, though.

I really like the PowerTech mufflers with the huge dual tips on them (straight through design). I'm going to check on the other mufflers mentioned before I make my final decision.

peace2u