Anyone Planning to Build a Muffler Like This?

[phm14]

I've been checking this forum to see what's in the pipeline as far as exhausts, and what I've seen so far seems to go beyond a simple muffler replacement, both in scope, and cost. Nothing wrong with that, per se, but do I need more than that? I researched exhausts extensively for my last 2 cars (see sig below), and found good independant test data that supports the fact that there's just not a lot of bolt on HP left on the table with todays cars, excepting FI. I've also been around long enough to know that some of these expensive, low yield mods can cause some ugly headaches in some cases. So the question in my head is are there enough gains to be had in the 86 exhaust, forward of the muffler, to justify spending a lot of cash?
Lets take a look at the factory header with all that heat shielding removed (borrowed this pic from another sticky here):


Maybe I don't know what I'm talking about, but that set up doesn't look too bad to me. Proximity to the oil pan alone tells me that heat shield is there for a damn good reason. I also seriously doubt that the factory cats are holding back much power in the NA engine, either.
That leaves us with the front & mid pipes, so I decided to get under my 86 and have a look. The factory system looks to be of very good quality-stainless components & good construction. Matter of fact, it looks to be built to last the life of the car. Seems a waste to chunk it and a large wad of cash that could be better used somewhere else. OD on the front pipe was just under 2.4", and the mid pipe OD was ~ 2.2", which seems close to good for a NA 2L motor. Didn't see any issues with routing, either. In time, independent dyno testing of piece by piece power yields may prove my guesswork wrong. Maybe a full system replacement will yield another 5-7 HP over muffler only, but in my case, I'll gain more by spending that money on seat time @ the track. To me, everything looked great, right up to the muffler. There, just like with my previous play cars, was the large, heavy stock unit that's responsible for most of the restriction in the system. After my under car tour, I decided that I will only replace what I feel is needed in the exhaust system-the muffler:

http://www.good-win-racing.com/Mazda...t/60-1337.html



This is what was on my NC MX-5. It provided what I wanted-a less restrictive, durable, perfectly fitted, lighter unit that gave great sound, and @ $399., it didn't cost half of what I'm seeing catback systems for the 86 priced at. So, as soon as somebody produces a unit something like the Roadstersport Q at a similar price point, I will buy one. Anyone else?

[MANDALAY]

Might be dearer but im sure Remus will have a unit soon. and they sound great

[raventare]

I guess after reading the Perrin Blog all of what is said here is just another persons unsubstantiated opinion and should be taken with a grain of salt...watch out on the track when one of those aftermarket exhaust systems comes rolling by. If you believe that everything is at maximum in a OEM mass produced car, pinch yourself and wake up. They produce cars to fit in a bell shaped curve for a price point and that is not the edge of the curve but the middle. If you have a "track car", that is not modified, then no matter how good you drive you will be an also ran. To get 10hp out of the exhaust is awesome on a car like this and on the track, real racers pay big bucks just for one or two hp especially in stock classes that are highly regulated...every ounce removed and HP added is dear.

That muffler does look good though...

[WolfsFang]

Their is some data sheets the say a exhaust and intake smooth out the torque dip, that alone is enough to convince me to get a exhaust.

[Mild2Wild]

I think engines like the K series and to some extent the VQ motors prove that NA imports can show dramatic increases in power. Already, with companies such as Perrin showing 7whp gains with simply a catback, many anticipate that significant gains will also be made with the addition of a replacement header. The major concern, and probably the one most indicative of the changes made by manufacturers today is the necessity of cracking the ecu to take full advantage of the possible gains afforded by flow improvements.

[dabocx]

Go look what the k20 guys on the 8th gen forums gain with header+exhaust +tune

[phm14]

Originally Posted by raventare

That muffler does look good though...

Yes it does. It's also USA made, and has a lifetime warranty. I have read the info here from Perrin and others. The numbers from Perrin don't include a test of the muffler alone, so it's not possible to measure the gain by replacing pipe forward of the axle vs axle back. The info from nameless says the ECU is correcting initial gains back down to stock levels, so a software solution may be needed for any immediate benefit other than sound. Developement of these systems is a trial process, and I have followed exhaust development on several different platforms. I've also been wrenching on cars for ~35 years, and tracking my cars for ~4 years, so of course, I have my opinions just like everyone else. My post was simply my opinion on what I want as a consumer, and why I've come to the conclusion I have, for me. I'm not building a spec racer, I'm tracking a street car.

[Mild2Wild]

Indeed. I came to the frs from an '08 Si and it's not uncommon for them to put down 220+ with IHE+tune. These often represent gains of more than 25whp over stock. They flow well enough that full 3" exhausts can be used without seeing the low end losses one might anticipate.

[serialk11r]

Stock exhaust is aluminized mild steel, not stainless.

[phm14]

Originally Posted by Mild2Wild

Indeed. I came to the frs from an '08 Si and it's not uncommon for them to put down 220+ with IHE+tune. These often represent gains of more than 25whp over stock. They flow well enough that full 3" exhausts can be used without seeing the low end losses one might anticipate.

How much of the gain is tune vs exhaust, and what kind of $ is involved? In any case, what good is all that power if the driver doesn't know how to use it. I can't count how many times I've seen guy in a high HP car blow by a 100 HP NA miata beater on a long straight, only to be caught in 2 turns, and have to give the the car that cost $5K a point by out the window of his $80K car. Just never gets old. Point is, true speed is about skill, not HP. If you just want to drive in straight line, or just like putting time & cash into big HP, that's cool-just not what I'm into. I'm not going to be messing with my ECU anytime soon. If I wanted a high HP car, I'd have bought one.

[phm14]

Originally Posted by serialk11r

Stock exhaust is aluminized mild steel, not stainless.

Huh, looks like SS. I could be wrong, I frequently am.

[Mild2Wild]

The midrange gains in the K20 are realized by lowering the rpm at which vtec engages in addition to the bolt on parts. The tune also realizes some peak power and raises the rpm limit. The parts and the tune are both important pieces of the puzzle but, at least in my opinion, the hondata flashpro is absolutely a must for those cars, as even when stock the mid range gains by lowering vtec make the car much more driveable. All said and done its about 2500$ for quality parts. If you're concerned with reliability, there are many examples of drivers with 75k+ mileage cars that are trouble free. Of course driver mods are the best bang for the buck. But even a pro can only polish a turd so much.

[phm14]

Originally Posted by Mild2Wild

The midrange gains in the K20 are realized by lowering the rpm at which vtec engages in addition to the bolt on parts. The tune also realizes some peak power and raises the rpm limit. The parts and the tune are both important pieces of the puzzle but, at least in my opinion, the hondata flashpro is absolutely a must for those cars, as even when stock the mid range gains by lowering vtec make the car much more driveable. All said and done its about 2500$ for quality parts. If you're concerned with reliability, there are many examples of drivers with 75k+ mileage cars that are trouble free. Of course driver mods are the best bang for the buck. But even a pro can only polish a turd so much.

Agreed on all points. I owned a CR. Every car is different. I accepted the fact that there will always be better drivers than me a long time ago, regardless of platform. I try not to take it too seriously & just have fun.

[Boosted2.0]

Originally Posted by serialk11r

Stock exhaust is aluminized mild steel, not stainless.

Per the Scion FRS NCF:

A stainless steel exhaust manifold and exhaust pipe have been adopted to ensure lighter weight and good corrosion resistance.

(b) Exhaust Pipe
(1) The exhaust pipes are made of stainless steel for improved rust resistance.