OK, So I'm new to this. I have changed the exhaust on my 7 and left the two hoses hanging that used to go into the exhaust. What am I hurting by just leaving them open to the atmosphere? I read a while back that I need to remove the belt to the air pump, why?

 

I'll be the first to say that it Depends... Does the state of Iowa test emissions?

If not, there is a whole SLEW of stuff on there that you don't really need (including the Air Pump) Removing the Air Pump belt is said to add a few more HP (maybe 1-3?) Search for "Rat's nest removal".

If so, I believe you really need the air pump to help with emissions.

 

Iowa does not test emissions. I have not had the time to remove the "rats nest" yet. I Will get rid of it sooner or later. Am I hurting anything by leaving the hoses out that went to the exhaust? I know that those had to do with the emissions? Is this thing going to quit running tomorrow?

 

I dunno.

My first instinct for hoses that aren't used anymore is to plug 'em off. Again, check out the "Rat's nest removal" tutorial. If you see these hoses being plugged off, then that's probably what you need to do. Seems like one of those exhaust hoses had a valve on it. If so, then the carb could suck vacuum at the wrong time and could cause a problem with it running. Plugging it off should prevent that...

 

No, it will not have any effect on the running of the vehicle, rx7doctor

 

if the air pump is still driven (by the fan belt) it just means that when the engine is turning, there will be air blowing out of the pipe! no harm, just unneeded drag on the engine, and unneeded weight of the airpump, mine was removed Loooong ago.

 

I've simply kept my airpump, with the belt turning it, since 1998 (when I installed my RB streetport exhaust system). Yes it blows to nothing, but so what. But, if my county begins air emissions testing as I suspect it will as they do so in Wake County, already (N.C.), I'll always have the option to use it for the original exhaust that I keep hung on the garage wall. Just a simple swap out for inspection time, only.

You'll still get power gains by using the RB streetport exhaust and leaving the airpump intact.

 

I guess that I will just be leaving it on for now. Thats good to know considering I am driving the car about 140 miles today. How long will it take to rmove the rats nest if I am a desent mechanic? Are any new parts needed for this process?

 

It took me a couple hours for the whole process. Just regular hand tools are needed IIRC