OBX Cat Bypass Pipe

[Rodsrsr]

I doubt it will make much of a difference on a motor with less than 225 hp.

[Roger 911]

Originally Posted by Rodsrsr

I doubt it will make much of a difference on a motor with less than 225 hp.

Exactly. If I was spending a lot of money on a larger throttle body, Extrude Honing the intakes, performance muffler, then I would not feel comfortable using this pipe. But for a basically stock motor, with stock muffler. I think it will be fine.

Roger

[KTL]

The shame of this debate in my mind is that there's probably more to come in the future. Meaning, keep an eye on those welds. A few guys who bought the OBX headers (the "shorty" type like George's European Racing Headers) have had problems with welds breaking.

One more cliche' that always seems to apply in situations like this. "If it seems to good to be true, it probably is." I'm not one to like overspending on stuff when it's not necessary and it does seem the other premufflers are rather expensive. But when OBX undercuts the competitions costs by a HUGE amount? Something's up.

[millarg]

Just installed an OBX Cat Bypass ($140 shipped on ebay - I got hit for extra shipping!) on my Bitz EFI equipped SC.

I couldn't be happier, I believe (could be wishful thinking) there is a significant power improvement, my 35yr old cat was probably completely clogged!

Also I had an irritating jerking shudder (one of those stomach jarring ones) at low/med rpm in second gear which seems to have gone )

For the money $140 plus about $30 in parts from our host, this appears to have yielded great drivability and power improvements.

[Junkbone]

Bringing this one back from the dead to add another opinion. Just picked up an OBX Cat bypass. Same issue as the OP's. Beautiful looking pipe, welds look great but again, the ports are off. I researched, and even read this post before buying and expected some flaws. I spent 79 on the pipe, 94 total with shipping and spent 15 minutes in the garage with a Dremel tool. I'm happy enough for a stock 3.2/SW chip, and think it will flow better than a 28 year old Cat.

[gtc]

What do you suppose cracks more often... OBX headers or M&K mufflers?

Originally Posted by KTL

The shame of this debate in my mind is that there's probably more to come in the future. Meaning, keep an eye on those welds. A few guys who bought the OBX headers (the "shorty" type like George's European Racing Headers) have had problems with welds breaking.

One more cliche' that always seems to apply in situations like this. "If it seems to good to be true, it probably is." I'm not one to like overspending on stuff when it's not necessary and it does seem the other premufflers are rather expensive. But when OBX undercuts the competitions costs by a HUGE amount? Something's up.

[RarlyL8]

Unfortunately the materials alone that we use (321 Stainless) cost more than a completed Asian version of the Premuffler.
We are the only manufacturer that I am aware of that incoprporates a merge collector, places the O2 sensor in the mixed path, uses 321 stainless, and spun end caps. There is nothing stamped and no shortcuts taken with our product. Made in the USA and the stainless is USA aviation grade. All of that is very expensive; worthy of a Porsche.
Here is one in optional brushed finish.

[Junkbone]

Without a doubt. RarlyL8, Fabspeed, Dansk even...... I'm sure you guys have a way superior product. But.....The cost of working on these cars are high. I was given mine to me on my mothers death bed and now feel a certain obligation to keep it in top form. Thats hard to do at a middle class job and a family. I'm used to working on old aircooled VW's.......that was hard even. Now I'm looking at Porsche prices. It may take me a year to save up enough to buy a decent sport muffler. The point, OBX Cat bypass. Needs some work out of the box,...but still,..For people in a position like myself. Not too bad if you understand flow, and know how to turn a wrench or two. (grinder/Dremel)

[DanielDudley]

I'd like to see someone dyno an OBX. Or a shoot out comparison of gains. It isn't really clear to me how much else matters for gains on a stock engine, although I have to day that the MK looks like it should absolutely perform better. What we are missing is facts.

[RarlyL8]

Our premuffler is not in the same category as any of the other brands mentioned. You can easily see the difference in this picture of used mufflers below. All the others are stamped merge and 304 or lesser steel. Many "manufacturers" outsource to China. We do not.




I completely understand the difficulty of maintaining these cars on a budget. The world changed in 2008 and probably will never be the same again. Cheap Asian goods have flooded the market and are hard to resist. Given that, many low mileage Porsches are going back to stock to be sold so there are some good used parts out there. A used M&K premuffler will outlast any of the others' new offerings and is a better design. If you can find one and save a few bucks then snag it.

[euro911sc]

Originally Posted by KTL

The shame of this debate in my mind is that there's probably more to come in the future. Meaning, keep an eye on those welds. A few guys who bought the OBX headers (the "shorty" type like George's European Racing Headers) have had problems with welds breaking.

I was one of 'those guys'... I had both the long and short headers fail... This is the 1st company that I actually feel compelled to speak out on...

OBX products suck big dead donky member. Follow that up with their customer service spews excrement out orifices they call mouths... IF you actually can get one on the phone. The supplier I bought from went out of business a year later.

I will not purchase another OBX product again and I will vehemently make my views on OBX known to all who do and are considering doing so.

Enjoy!

-Michael

[euro911sc]

Originally Posted by gtc

What do you suppose cracks more often... OBX headers or M&K mufflers?

hahaha I have the answer! Pick me Pick me!

My M&K w/ Georges headers have lasted 10 years on the track. My 2 sets of OBX headers cracked and fell apart with in 6 months of street ONLY use. My engine is stock so its not like I'm putting a whole lot of unusual strain on them.


Look, I understand the budget thing. I am there myself. It's like I tell folks when they ask about harbor freight products. If you expect to be relying on it for accuracy, precision, fit, or finish you probably wont be pleased with buying there. However, my light weight racing jack which needs not accuracy, precision, fit, or finish has lasted me almost 15 years. *shrug* you almost have to go product by product these days... YMMV!

-Michael

[Rich Gas]

Messing with the exhaust has always been hit or miss. But, we can all agree that getting rid of weight back there and allowing extra flow is the target. I've spent thousands messing with mine, and it's still too loud. If I could get it 20dbs lower and still have the deep tone and snap crackle pop I have now, I would be happy.

[euro911sc]

Originally Posted by euro911sc

My M&K w/ Georges headers have lasted 10 years on the track. My 2 sets of OBX headers cracked and fell apart with in 6 months of street ONLY use. My engine is stock so its not like I'm putting a whole lot of unusual strain on them.

Apparently I lied... cost of old age I guess... They lased 1 track day. Here is my post on it from years ago:

OBX Headers Cracked apart...

[Junkbone]

Follow up to my earlier post. OBX is on. Other than the ports, alignment was a bit off. At the angle that the pipe mounted, the muffler had to be loosened up and dropped down about an inch. This causes it to be cockeyed. For now. I may or may not shim the other side. You don't really see it. No awesome sporty sound change to speak of. Mainly though, my butt says no performance gains at all and I'm wishing I had done a baseline dyno beforehand. It could just be a mental illusion, but I actually feel as though I lost a bit of mid range. Soo, if it doesn't crack, fall off, or kill little puppies, I just have a purdy pipe.

[freeform911]

OBX SUCKS...I bought one for my 86 and all the welds cracked within a year...good luck..
Steve

[Roger 911]

4 year update...

Good news, bad news. Good news...the OBX still appears to be in one piece without any cracks. Bad news...that still makes it harder for me to justify buying an M & K

[jlex]

I'd like to replace the cat on my '88 3.2 so I can use ZDDP laced oil to protect the engine without clogging the cat. So what's the difference between the pre-muffler and the cat pipe? Pipe just noisier? Anyone out there think the cat pipe is too noisy for an old guy like myself?
Just running a standard muffler that I'm happy with.

[Roger 911]

Originally Posted by jlex

I'd like to replace the cat on my '88 3.2 so I can use ZDDP laced oil to protect the engine without clogging the cat. So what's the difference between the pre-muffler and the cat pipe? Pipe just noisier? Anyone out there think the cat pipe is too noisy for an old guy like myself?
Just running a standard muffler that I'm happy with.

When I installed the cat bypass with the stock muffler, I barely noticed any change in sound. Admittedly, I had been running a 2.4 motor with Webers, SSIs, and M&K race mufflers for years, so everything short of megaphones sounded quiet to me! IMHO, as long as you have a stock muffler behind the cat/bypas/pre-muff, I don't think you will notice that much of a difference. But again, it may depend on your frame of reference.

Roger

[Jesse16]

To Jlex, my MK cat pipe and then later the premuffler were/are both louder than a cat. I believe Brian (maybe) at MK told me the sound difference between the pipe and premuff is only slight in actuality, I'd believe that. Mines not too bad but every increase in exhaust noise means less interest in hearing the radio ! You won't annoy the neighbors and a nice sound on track days! Nice clean look when installed.