Ok, heres the spill. About a month ago my 1980 SA was running fine so I decided to do an exhaust upgrade, well since the car was parked i figured i would go ahead and replace the radiator, remove the rats nest and air pump, and replace the radiator. I got the RB exhaust today and I put it on and cranked it up. It idled alright but when I revved it past 2000 it quits revving and backfires. I have done a visual inspection of the vacuum lines and could find nothing. What do you guys think is the problem. Could the exhaust have something to do with this or is it more the intake/vacuum lines.

 

intake and vacuum lines. also, check your water pump, if you didnt add a dual alternator pully or the yoohoo belt it will slip at high RPMs.

 

Vacuum leak, exhaust leak, error in rats nest proceedure. Water pump won't cause your problem, but the dual pulley or yoohoo belt is a good suggestion.

 

Make sure that the blockoff plates you received with the exhaust system are installed properly.

 

could you explain to me proper installation.

 

Bump. I forgot to mention that when i took the rats nest off i cut the plugs off. Could this have something to do with it.

 

bump

 

When you bought the RB header, it *should* have had some metal plates included. These are for blocking off the air control valve and air injection. They really need to be used.
When you say you cut the plugs off, which plugs? Hopefully, not the float bowl vent solenoid.

 

I used the block off plates, what i meant was do i need to use just rtv or just make a gasket out of a sheet of gasket material. the plugs i was talking about are the ones goin to the rats nest.

 

When you say you "cut the plugs off", what do you mean exactly? Also, I'm pretty sure that when I installed the blockoff plates I just used some rtv on them...

 

When I bought my RB header, I was handed a bag with the plates, and a full gasket inside.
I'm not sure how the SA ACV is set up, but the FB ACV also diverts some air into the front rotor VIA the anti-afterburn valve #1. Without a gasket to seal the blockoff plate, exhaust can leak into the intake, VIA this AAV passage.
Either coat the entire back of the plate(s) with rtv, or make a gasket. This will insure they are fully sealed.

 

I mean that i took a wire cutter and cut them off about two inches from the plug at the rats nest.

Also, Rogue Wulff, I made a gasket using Felpro gasket material but i still seem to have a vacuum leak and all of my other vacuum lines are brand new.