I have my stock exhaust in place, and I'm hoping to fix that problem soon. However, it's supposed to be nice this weekend, and I may have the urge to pull the air pump out of the car.

Realistically, is this a sudden death thing for the cats, or will they gradually melt? Considering the temperature outside (50 degrees on a nice day), 87 octane gas, stock carb, how long do I have to remove them after taking out the air pump before I damage something or there is a negative impact?

 

you pull the airpump when you pull the cats. Why keep cats if you're taking off the pump? The two work together.

 

I've been wondering some of the same things... actually either tonight or tomorrow i'm getting a good old screw driver to my cats until i can afford a RB exhaust system

 

Like I said, I don't plan to leave one in without the other for long. But if I'm bored, I may start pulling emissions stuff off the car (got it inspected last week). It may be a week or two before I have a chance to gut the cats.

 

Let them melt. Then you dont have to pull them off. They just explode in a giant fireball like mine did, on the highway, at 85mph.

 

I really hope your joking. Don't take that advice Narcisse and not expect bad things to happen. Not only when they melt and plug up causing less horsepower, but also cause higher then stock back-pressure which is hard on the engine(yes, we all heard that annoying thread about back pressure, but one can only assume when exhuast has to really push around a hunk of melted honeycomb catalist, it obstructs flow). I never heard of them exploding unless the pipe was about to give way anyway and hit the road and that is the explotion you heard along with sparks and fire.

 

tuned pressure = good

clogged or melted cat causing over backpressure = very, very bad

 

Don't worry, I'm well aware of why I don't want them to melt.

Every nice day I've been on the bike, so by the time I get around to the air pump, I'll probably have a replacement pipe here anyway.

 

it will cause a thermo nuclear melt down, thus throw off the jigawatts going to the flux capacitor. this could render your right rear wheel vulnerable to exploding and leaving you stuck in the space/time continuum.

 

Heh, my friend's REPU rear header pipe exploded two inches from the flange. His dellorto lets lots of gas leak down into the engine and it got pushed into the exhaust. Then when he cranked the engine, the incoming burning AF mixture ignited the extra gas in the pipe and burst it slightly. A 3/8" chunk was missing causing a really loud ticking sound. The metal is 1/8" thick with spiderweb type cracks branching away from the hole. He had it welded and it should be good for a while. Oh, his rear rotor had bad apex springs too. That could have something to do with it. It's getting rebuilt, so we don't expect any more exhaust probs for a while.

That story didn't have much to do with the topic of this thread, but exploding exhaust pipes do happen.

 

Great, thanks for your input.

 

i had my air pipes to cats dissconnected accedentally 2 months before i bought my 83, and a month after my engine broke down, due to over back pressure, the cats were hard for even me to blow through, I seriously suggest taking them off and replacing them with basic straight pipes, cost me 30 bucks and tooks me 1 hour and a half, really worth it

 

You mean... oh no... NOT THE FLUX CAPACITOR!

Those things are getting hard to get ahold of nowadays.... and cost a pretty penny too...

And if you're stuck in the space/time continuum, it'll even harder to get ahold of one...