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HiI have tooke off the cat time ago ,and there were a few power increase low end like 1-2 hp ,but from 4000rpm there were no gaing,this was with a 2.25 mandrel bent cat back cai and 18 timing adv.
may be with nitrous the gaings can be high.
 

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I tell you what, when I had my Merkur XR4Ti, a german Ford 4 banger turbo, it helped a lot when I removed my cat. Turbo seemed to spool up about 2-300 rpm quicker and she just flat out flew from 50mph on. Of course I had many other mods but I did notice a difference once the cat was removed. That car did not have an O2 sensor mounted in the cat either.

So I imagine with some NOS, kind of a short burst turbo, gains should be as good or near as good. I mean it cant hurt, unless you have emissions testing, then well, yer screwed.

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95 200SX SE-R--> Hot Shot CAI, Custom Apexi Cat Back, ST Shifter & G4 Hotshot Headers, Viteks and Iridium, B&G springs, 17" Konig Tantrums wrapped in Nitto's, a bunch of stiffening and look good crap, 91 Cams, JWT CPU COMING SOON!
 

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I had the same motor in a Thunderbird Turbo Coupe. Definitly made a difference with the cat gutted so I agree it would probably help out with NOS as well. I have heard that NOS can actually clog up the cat too.
 

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Yeah, I heard that cloggin theory from many folks too. Guess it has to be true unless your cat is a real flower. It seems I will be adding NOS this weekend, just picked up an entire 50 shot kit, one month old form a friend that blew his tranny in a 2000 impreza! no, he cant drive very well at all.
 

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Yes, there is power to be gained. In N/A trim the gains are minimal but are there. Whenever you go forced induction of any kind they like less back preassure. I did it, it's no biggie.

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98 200SX SE-R, CAI, Greedy Exhaust, JWT Motor Mounts, Pullies, Nismo fuel press.reg, JWT C1 cams and JWT gears, Valve Springs and Titanium Retainers, ACT HD/PP, Clutchmasters Flywheel, JWT Computer,Bored Airflow Meter.
 

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o.k., quick question to b14 owners.....

we have obdII emissions, therefore, we have an o2 sensor in the manifold, and an o2 sensor in the catalytic converter. if you run a test pipe in place of the cat, what did you do with the o2 sensor? didn't you get a bunch of trouble codes driving around without it? i'm running a 50 shot of nitrous, and was wondering about this mod for track days.

1996 b14 se-r
 

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Hey, Project. What year Mekur? What did you have done? I used to have an XR4Ti and a Scorpio. I still have a soft spot for those cars.
 

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Mine was an 88, and a 5-speed with the 175HP stock as opposed to the crappy 145HP for the auto. I was running a T3/T4 hybrid as opposed to the stock T3 and ran the Rapido intercooler setup. I had the rotated upper intake manifold and throttle body from a Mustang, as well as bigger injectors and FP. Of course an adjustable FPR and substituted a HUGE blow-off valve for the Rapido issued one. I also changed out the crappy T-9 tranny for the much more durable T-5 from a mustang and then slapped in the LSD that Rapido sells. I was running the air flow meter from the Turbo Coupe, much more air flow! I think the max boost I had set was around 19 or 20 pounds. We had tried to run the dual plug head from a ranger but we couldnt seem to get everything smooth, so I went back to the stocker. Then ran the Superchip to make everything work together.

Overall she screamed like scalded dog, but I ended up blowing a head gasket and had to sell her. I really miss that car, it was really fun. People used to pull up next to me thinking is was some new Saab or Escort...hehe, little did they know I was topping 300HP!

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95 200SX SE-R--> Hot Shot CAI, Custom Apexi Cat Back, ST Shifter & G4 Hotshot Headers, Viteks and Iridium, B&G springs, 17" Konig Tantrums wrapped in Nitto's, a bunch of stiffening and look good crap, 91 Cams, JWT CPU COMING SOON!





[This message has been edited by ProjectSE-R (edited 10-02-2001).]
 

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<font face="Verdana, Arial" size="2">didn't you get a bunch of trouble codes driving around without it? </font>
No, you just get one trouble code constantly. I have the 97 ECU in a 99. The rear O2 sensor is a different type and I never switched it so the ECU thinks something is wrong. The problem is that you can't tell if a new trouble code appears.

I encourage you to get a pipe with flanges to fit in place of the cat for race purposes and use the cat at all other times.
 

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<font face="Verdana, Arial" size="2">Originally posted by nitrous_50:
o.k., quick question to b14 owners.....

we have obdII emissions, therefore, we have an o2 sensor in the manifold, and an o2 sensor in the catalytic converter. if you run a test pipe in place of the cat, what did you do with the o2 sensor
1996 b14 se-r
</font>
what you can do is find a nut that screws onto the o2 sensor, drill a hole in the test pipe, and weld the nut in its place.

it would be best however if you could find an old b14 cat and gut the mofo.


markp
red200sxser
AIM:mapball20
 

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thanks for the responses :).

another oddball one , when you get a trouble code, sometimes the computer likes to act funny. i.e., if it senses an error with the front or rear o2 sensor it may run in open loop format or closed loop format full time. and this would equate to a different idle speed even when warmed up, and maybe different timing settings, advanced or retarded too much. i wouldn't be worried too much running NA, but with nitrous, you give it respect, and try not to take chances.

thanks in advance,
bryan

1996 200sx se-r
JWT intake, JWT computer/nitrous program, pullies, JWT 50 shot, ACT clutch, JUN flywheel

14.1 @ 99 mph on street tires

[This message has been edited by nitrous_50 (edited 10-02-2001).]
 

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Hollow it out and weld in a 21/4 or 2.5 or a diameter pipe that will fit that goes straight through the length of the cat. This will direct the airflow undisturbed, if you just hollow it out you will lose about 1-2hp low/mid.

Alfie
<Nitrous killed my cat>



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92'XE/w-Primera swap
sleepr w/N20
 
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