RMB or Cat Bypass?
#1
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I really dont like the risk of keeping the cats..
I want to do a bypass and was wondering if that in and of itself will add HP and add to the grow.
87S4
I want to do a bypass and was wondering if that in and of itself will add HP and add to the grow.
87S4
#2
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If the car is running right the cats have no issues. An X pipe from Roger without cats is a good bang for the buck, but the first thing to do (if it hasn't been done yet) is new intake gaskets, MAF, knock sensors, plug wires and related top end things then you will be sure the car is running as it should.
#4
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For simplicity and acoustics, I'd suggest the RMB. Stock plus RMB sounds gorgeous, you drop a chunk of dead weight off the rear, and maybe add a couple hp while remaining utterly legal at every state inspection office.
X pipe is where the more serious hp is, but not always the best sound quality. Cats often get tossed as part of the x-pipe operation, but honestly a set of high-flow ones won't hurt the hp much and now you're legit... at least in spirit as much as letter of the law.
X pipe is where the more serious hp is, but not always the best sound quality. Cats often get tossed as part of the x-pipe operation, but honestly a set of high-flow ones won't hurt the hp much and now you're legit... at least in spirit as much as letter of the law.
#6
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As others have already said, the best bang for your buck is an X-Pipe. Skip the cats, and throw your factory cat on the shelf. We only do emissions every two years here in some MD counties. It's not a big deal to swap the X-pipe for the cats once every two years.
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#8
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If you really need more power the X-pipe will give you by far the most bang for the buck. X-pipe , gutted cats and RMB will likely be WAY too loud for typical street driving unless you want to turn heads every time you get on it. Not to mention the drone at cruising speed...
The apparent best compromise judging by member responses is using the X-pipe, factory cats, early S4 (87-88 I believe) resonators, and RMB.
If you don't need any more power but want a great sound, consider just the RMB with the stock system. That's what I have and love the sound both at idle and full throttle.
Not sure what you mean about "don't like the risk of keeping the cats"
The apparent best compromise judging by member responses is using the X-pipe, factory cats, early S4 (87-88 I believe) resonators, and RMB.
If you don't need any more power but want a great sound, consider just the RMB with the stock system. That's what I have and love the sound both at idle and full throttle.
Not sure what you mean about "don't like the risk of keeping the cats"
#9
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In MD, historic vehicles such as your 87 will not require emissions. I just purchased the x from ROger with the cat delte, but yet to install so I can't really chime in on the sound quality. The x is better for hp, the rmb is better for sound. Both together have been found to be a tad bit too loud.
#10
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The problem with historic tags in MD is that they technically limit your use of the vehicle. I've never heard of this being enforced and a lot of people are doing it to get around the emissions test with their old, beat down ****. But as I said before, it's not a big deal to throw the factory cat on the car for a few days, once every two years. I just did it a few weeks ago.
#12
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looks like i was leaning in the right direction..a x pipe and no cats...i dont like the heat issues with the cats...I thought that the sound would be too much if i also did the RMB...i looked for the bypass.....can someone put the links up to the suppliers...thnx guys
john
john
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+1 for doing both. Thats what I have on the 87 and love it. Makes power. Droons a bit at 80 MPH so I drive faster or slower on long drives. 80 seems to set up a harmonic that I find annoying.
#14
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The problem with historic tags in MD is that they technically limit your use of the vehicle. I've never heard of this being enforced and a lot of people are doing it to get around the emissions test with their old, beat down ****. But as I said before, it's not a big deal to throw the factory cat on the car for a few days, once every two years. I just did it a few weeks ago.
And yes, I do see a lot of beaters on the road with historic tags.
#15
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I have the X-Pipe, cat delete, and RMB on my 87, and I love the sound except when leaving for work at 6:30 in the morning. One thing to mention is the ugly yellow stain that appears on my white rear that I have to clean off every 2 weeks or so from the exhaust, and the car is tuned properly.