will i have enough back pressure
07-25-2003, 11:01 PM
#1
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will i have enough back pressure
well here is my issue i have a borla header and and a apexi cat back but a stock cat. but today i through a check e light it was my cat. so now what do i do if i put a high flow cat on will it have enought back pressure or will i have to get a oe cat. i belive that apexi is a 2 1/2 in. pipe. well hope you guys can help. oh yea its a 2000 rs. sorry
Last edited by sUbEe; 07-25-2003 at 11:07 PM.
07-25-2003, 11:51 PM
#2
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Get the code pulled, but I can say with 99% surety that the code is Cat Inefficiency. Wrapping the Borlas is supposed to take care of it but I haven't wrapped mine yet, and I have the CEL. I will post about it if I get around to doing it. Right now the CEL just isn't bothering me as much as the thought of buying and installing wrap and painting it. 
There is also the resistor fix.
Backpressure isn't likely to cause a CEL. The 2.5" pipe is ok, not hurting anything, but overall you'll have more power with 2.25" pipe. The 2.5" actually has slightly more peak hp, but less torque overall.
There is also the resistor fix.Backpressure isn't likely to cause a CEL. The 2.5" pipe is ok, not hurting anything, but overall you'll have more power with 2.25" pipe. The 2.5" actually has slightly more peak hp, but less torque overall.
07-25-2003, 11:59 PM
#3
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when i got it checked they said it was the cat. you dont think that is my prob? just wrapping my header should shut off the cel? and you think that with all that high flow pipe i can get away with a high flow cat? well i guess i am going to start by wrapping the header and go from there thanks man
07-26-2003, 04:17 PM
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The actual code is "catalytic converter inefficiency" which means the cat isn't working right. However, with the Borlas, it's usually because it isn't getting hot enough to work properly. The stock headers are double-wall steel with heat shields- the Borlas are just single wall stainless. By the time the exhaust gets gets back to the cat, the temps are 100-200 degrees cooler than the cat needs to function. Wrapping the headers should take care of this problem, but no guarantees. I will be trying it on mine soon, and will post results.
07-28-2003, 09:07 PM
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While we are on the subject of wrapping the Borla's. I've seen posts that say that this is bad just because of the temperatures and damage it will inflict in the long run to the headers such as cracks to the metal or welds. I have been wanting to wrap my headers because I have my plastic crap guard off because if I put it back on, it's right by the headers. Would it be very damaging if I put a wrap just on the parts that are too close to the guard? Is there some kind of protection I can put on the guard instead, or am I just better off getting a skid plate like the Primitive?
07-28-2003, 09:16 PM
#8
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It shouldn't hurt the gen IVs. The cracking was due to the cross piece welded across all of the collectors next to the driver's side head. The new ones don't have that.
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