Questions about Catless Front Pipe (previously Need Clarification thread)

[JFox]

Hey guys and gals,

I'm a little new car mods. I'm darn good with a wrench if I do say to myself, but car mods (especially exhaust) are pretty new to me, so go easy. I'm trying to learn!

So I already have the Perrin 2.5" cat-back system w/ resonator. I installed it and I LOVE it. The noise it makes is heavenly and doesn't sound like an out-of-tune trumpet.

That said, I've caught the bug and now I want more. The exhaust itself isn't very loud at all from inside the car, and I'm slightly disappointed by the lack of aggressive idle sound (except cold start...WHEW that thing rumbles!).

I've been looking at the Invidia HS12SSTFPP Front Pipe (catless) to replace stock setup. My question is A) Is this even compatible with the Perrin cat-back system, and B) what would this sound like? I'm definitely a fan of the low-tone exhaust notes, and not at all a fan of the higher notes.

Am I correct in my assumption that this piece would bridge the gap between the headers and the Perrin cat-back? Or would I still need another section of pipe? It looks like I still need an overpipe. Is there a cheaper option compared to the Perrin overpipe?

Are there any alternatives for a more aggressive sound minus just installing the unresonated Perrin piece? Are there other/better front pipes to be had? I like the price of the Invidia...but I'd probably pay a little more for better quality, if such a thing existed.

Thanks a bunch guys.

[Ghost 86]

The invidia front pipe should fit just fine as for the over pipe I'd just wait until you get a header for that or if you really must have it get one with the same diameter piping as the front pipe. As you'll see a lot of the exhaust parts for this car get kinda expensive for the smaller parts compared to what you paid for your catback.

[ToyoburuBRZ]

Hey JFox... I will try to answer your questions one by one here.

A) The Invidia front pipe is compatible with your Perrin cat-back.

B) This setup will definitely be louder. Usually the front pipe will make things a little deeper. However, going catless, it will more than likely be raspy and potentially drone (I will come back to this).

C) This will not bridge the gap between your cat-back and your header. There are two pipes in there that would need to be replaced - the front pipe and the over pipe.

I would recommend going with the Nameless over pipe/down pipe (aka front pipe) combo. It combines the front pipe and over pipe into one continuous pipe. I would also recommend getting the Helmholtz resonator and the high flow cat. The resonator will help keep the system drone free while the cat will help keep rasp down.

The nameless system is more expensive but a very high quality part that I guarantee you wont be disappointed in

[Migero86]

^^ Sound advice right there

[JFox]

Originally Posted by Ghost 86

The invidia front pipe should fit just fine as for the over pipe I'd just wait until you get a header for that or if you really must have it get one with the same diameter piping as the front pipe. As you'll see a lot of the exhaust parts for this car get kinda expensive for the smaller parts compared to what you paid for your catback.

Ah, okay this makes more sense now. Thanks!

Originally Posted by ToyoburuBRZ

Hey JFox... I will try to answer your questions one by one here.

A) The Invidia front pipe is compatible with your Perrin cat-back.

[truncated to improve readability]

Thank you so much for the details here. I believe I had it a bit backwards in my head. I thought it went Headers > Front Pipe > Overpipe > Cat-back when in reality the overpipe is what connects the front pipe to the cat-back.

So essentially, for my purposes, there would be no reason to even touch the over-pipe. Which is good, because I was under the impression replacing some of this would require loosening the motor mounts and jacking the engine up. I'd rather avoid that if I can (just a lot of hassle).

In the scenario where I simply replaced the front pipe and left the stock overpipe, I could do this fairly easily, from the looks of the video of installing the Perrin front-pipe/overpipe combo.

So, when considering the front pipe, what about instead of just a straight pipe, I went with a resonated version like this: [ame="http://www.amazon.com/gp/product/B00AFFVRNO/ref=s9_simh_gw_p263_d0_i1?pf_rd_m=ATVPDKIKX0DER&pf _rd_s=center-2&pf_rd_r=0N9FEW18ZYM9VDKGKDR2&pf_rd_t=101&pf_rd_p =1688200382&pf_rd_i=507846"]Amazon.com: Invidia HS12SSTFPR Front Pipe with Resonator for Subaru BR-Z/Scion FR-S: Automotive[/ame] That should help reduce rasp, especially considering I already have the resonated version of the Perrin cat-back, right?

Also, I don't mean to discount your advice on the Nameless. I had heard great things about them, I just would rather not mess with it if I can help it, y'know? I think just a front pipe will accomplish what I want.

[ToyoburuBRZ]

here is a diagram of the brz/frs exhaust system for your reference:



You are correct in saying that replacing the front pipe only is easier. If you were to do an over pipe or and OP/FP combo, you would have to raise the engine. But if you say you are good with a wrench, it is super easy to do.

Simply having a resonator wont reduce rasp. A resonator will reduce or remove droning. A resonator is designed to delete the specific sound waves that cause drone. The only way to really reduce rasp is to keep the cats in the exhaust system.

If you really don't want to replace the over pipe, Nameless (and just to mention I am not affiliated with them at all they just make some really top quality stuff!) also makes just a down pipe that you can get with a resonator and cat.

[JFox]

Originally Posted by ToyoburuBRZ

here is a diagram of the brz/frs exhaust system for your reference:

You are correct in saying that replacing the front pipe only is easier. If you were to do an over pipe or and OP/FP combo, you would have to raise the engine. But if you say you are good with a wrench, it is super easy to do.

Simply having a resonator wont reduce rasp. A resonator will reduce or remove droning. A resonator is designed to delete the specific sound waves that cause drone. The only way to really reduce rasp is to keep the cats in the exhaust system.

If you really don't want to replace the over pipe, Nameless (and just to mention I am not affiliated with them at all they just make some really top quality stuff!) also makes just a down pipe that you can get with a resonator and cat.

Sweet! Again, thank you for that information.

Regarding the overpipe...it's honestly not the amount of effort, it's just a hassle (= money) for probably not what I'm wanting to do here. My goal is to gain something for not a ton of money (isn't that everyone's?? LOL). It just looked good on paper to buy the Invidia pipe for just a touch over $200 and call it a day.

So I guess the question here is...would I really gain any volume at all by just replacing the stock front pipe with the Nameless (or any other catted) front pipe? I realize there's performance to be had here also.

[ToyoburuBRZ]

To be honest, I am not really sure how much of an effect just the front pipe has but I am certain you will see some gains.

I do know that the stock over pipe is rubbish and there is a lot to be gained there.

Is your priority to gain sound or power? If just sound, the front pipe will add some. If you want both spend the extra money and get an over pipe as well as a front pipe.

The main parts of the exhaust that you will really see hp gains from (other than the obvious header) are the over pipe, front pipe, and possibly the axle back. The mid pipe really doesn't do too much. That is why Nameless doesn't make a 2.5 inch mid pipe. But they see a 12hp gain just from over pipe, front pipe and axle back.

[JFox]

Originally Posted by ToyoburuBRZ

Is your priority to gain sound or power? If just sound, the front pipe will add some. If you want both spend the extra money and get an over pipe as well as a front pipe.

To be perfectly honest, I just want it to be louder by spending the least amount of money. I just dropped almost $900 on this catback, and I'd rather not spend another $500 on more exhaust parts (at the moment).

I've found a couple videos that show catless front pipes with Perrin catbacks and it seems like they're OK. The only two I could find seemed to have a small amount of rasp however they both had aftermarket headers and overpipes. I don't know if that increases or decreases the chances of having rasp. Seems like higher flow = more rasp, but that's just my theory.

Do you know of any videos that have a catless front pipe and Perrin catback?

[Smudgeous]

Originally Posted by JFox

To be perfectly honest, I just want it to be louder by spending the least amount of money. I just dropped almost $900 on this catback, and I'd rather not spend another $500 on more exhaust parts (at the moment).

I've found a couple videos that show catless front pipes with Perrin catbacks and it seems like they're OK. The only two I could find seemed to have a small amount of rasp however they both had aftermarket headers and overpipes. I don't know if that increases or decreases the chances of having rasp. Seems like higher flow = more rasp, but that's just my theory.

Do you know of any videos that have a catless front pipe and Perrin catback?

As I, too, was in this same boat when I first got my car, I'll offer my experience with this car.

At the time I was looking to pull the trigger on the exhaust (June of 2012), there weren't close to as many options as we have today. I decided to go with the complete header-back system from SRT, which is now known to be among the louder exhausts (though promised to not be overly loud when I originally pre-ordered it).

As it deleted the secondary cat, it was a lot louder and also did exhibit some drone at lower engine RPMs (I forget the exact range, but it was something like 1900-2200 RPM), but I don't ever remember finding it raspy. I've since added a second resonator to the midpipe, which has helped the drone, though it is worth noting that the lack of cat means it's still much louder than stock.

As far as installation, while the overpipe was annoying, I was still able to do the whole project lying on my back with the car on 4 jack stands. I did not need to jack the engine, though I did have to remove the 2-piece OEM heatshield from the overpipe to get it out.

As far as your own situation, I'd say your most flexibility would be to go catless for now and see what you think. You can always go to any muffler shop and have them weld in a resonator if it introduces drone, or a cat to reduce volume. It's worth noting that going this route allows you to specify the exact resonator/cat that you want, and not just accept whatever comes standard on the pipe you purchase.

For example, you could go with a super low cell count cat if the noise was just a bit too loud, vs. a higher count if it was much louder than you wanted. You may spend more money when all is said and done, but the installation at a muffler shop is relatively inexpensive, and allows you to have a solution that's more catered to your individual needs.

[Smudgeous]

Originally Posted by JFox

To be perfectly honest, I just want it to be louder by spending the least amount of money. I just dropped almost $900 on this catback, and I'd rather not spend another $500 on more exhaust parts (at the moment).

I've found a couple videos that show catless front pipes with Perrin catbacks and it seems like they're OK. The only two I could find seemed to have a small amount of rasp however they both had aftermarket headers and overpipes. I don't know if that increases or decreases the chances of having rasp. Seems like higher flow = more rasp, but that's just my theory.

Do you know of any videos that have a catless front pipe and Perrin catback?

Also, to answer your question, did a super quick search and found this thread: http://www.ft86club.com/forums/showthread.php?t=32140

[cdrazic93]

Nameless downpipe with helmholtz resonator and 200 cell cat. Reduces drone and rasp

http://shop.namelessperformance.com/...aces-overpipe/

I'm sure if you contact nameless on here you'll be able to get a better deal on it.

I'm not too happy with Invidia, welds could be better, sure they are cheap but in the end a nameless DP would last longer than a Invidia frontpipe. I always say do it once, and do it right the first time. No need to spend hundreds of dollars if there is any probability you may need to spend more just to fix anything that breaks!

[TruRace]

The fitment on the nameless was not so great for me. The flange bolting up to the header was not flush at all and required a bit of pulling/pushing to get to sit right. I was almost ready to send It back. I loosened up the catback and had to force the pipe into place leaving maybe a little under a 1/4" between the pipe and the block. I'm surprised it doesn't rattle. Great piece I just don't get how people carry on about the fitment. Maybe i got a bad batch.

[JFox]

Originally Posted by Smudgeous

As I, too, was in this same boat when I first got my car, I'll offer my experience with this car. [...]

Awesome input there! Thanks for that info and advice!

So yeah, that sounds like a great idea. I'm thinking more and more about the Nameless front pipe if I can get somebody to buy my stock front pipe. It would be nice to just go ahead and have a single piece front/overpipe. I imagine it might be difficult to install but after looking at a few more pictures, it seems like I could probably get away with doing it without lifting the engine.