If the split air pipe is no longer running into the cat would it make the car run any different? The jackass that did the muffler job just crimped it shut.

 

yea your 5th and 6th ports wont open w/o the back pressure, unless you have an alternate solution!!

do a search its out there!!

 

crimped the cat or the split aire pipe? crimping the pipe woudln't be smart as the ACV would be still trying to push air down it. unless the airpump is removed.

 

The 90 model does not depend on back pressure from the catalytic converter.

 

where does the 90's model depend upon then if not from the catalytic for the 5th and 6th port to open up.? im curious there.??

 

It is either done electronically or by the smog pump, can't remember.

 

s4 (86-88) rx-7s use the the back pressure.s5 (89-91) use the airpump to actuate the ports.

 

if its an s4 you can cut an 1/8" hole in the hose between the acv and the acv muffler and then get a vacuum coupling to to connect them.They will open at around 3,000 rpm instead of 3,800.

 

It's an s5. I know the auxillary ports don't open from the back pressure from the cat but would the split air pipe being uhooked/crimped shut cause the ports not to operate correctly after time? the airpump is still on and working fine. no mods to the car

 

bump