from the cat back!!!
 

ok i have a 87 N/A im going to put 2.5 all the way back from the cat. now my question is, from wich cat can i go back to still have the stock set up work to have the 5 and 6 port open up. i know we have like 3 cats so i wanted to take as many away as possible. also looking under the car yesterday, i saw this huge thing that looks like a muffler right before the Y pipe, is that a resonator or a Cat? i sure hope i can get rid of that huge ass thing and run my stright 2.5 pipe all the way back to my muffler. i was going to cut the stock exhaust right after the downpipe or right after where the tap in is for the backpressure line. so that i can use that stock set up and not have to worry about the 5 and 6 port now opening untill i bet moretime to eather search for more on how to hook it up the air pump or till someone on here can give easy step by step process how to do perhaps even picture would be nice.

please let me know as i will be working on this tonight and partially tomrrow.
thanks
andy

The HUGE thing before the muffler is the main cat. There are two other, smaller ones in front of it on the down pipe.

The Backpressure is taken from the little tube that attaches to the cat. If you were to go with a Bonez High flow Cat and down pipe system, you should still have enough backpressure to operate your six ports.

You get into trouble by removing the cat and then don't have enough backpressure in the exhaust to open the six ports.

IF you run a straight pipe and have no cat whatsoever, then you are going to have to do one of the "alternative" methods of opening the six ports!

ok now if i take out the big cat in the back but leave the two small ones on there and only run one muffler instead of two, will that still have enough back pressure? i was considering going to a single muffler anyways for the time being.
so that would leave me the two small cats and the fac. down pipe plus the backpressure tube too.

should this set up work ?
thanks again.

If you don't have to worry about emisions loos all the power robbing cats, the alternitave methods for actuating the 5th and 6th ports are easy and man did i get a huge gain when i scrapped the cats

i would love to take all the cats off but i know nothing about our cars. hell i dont even know where the air pump is to redue the line going to the air pump. does anyone have pics of theirs as a reference?
please let me know.
or does anyone want to help in the erea?

thanks again
andy


so if i take of the main cat will the 5 and 6 port open just if i cant get my confidence high enough to tap into the air pump i would still want to leave two cats and just take out the main back one and run 2.5 all theway back .
let me know please

anyone?

If you know very little about cars then I suggest using a RACING BEAT dual system. It bolts right to the cat. If you don't have to worry about emmissions, then take the cats off and rod them out if you don't replace them. My RB system is nice and perfomance went way up. The cats are clean through except the back mesh on the main. No ceramic left. Pretty much free flow.

Oh, Sound in good and deep!

I will say this again.......

the backpressure pickup tube is ATTACHED TO THE CAT... thus... its gets its backpresure FROM THE CAT and the mufflers which are downstream of the cat....

if you remove the main cat, you are going to lose the backpressure from the cat and your sixports will most likely not work.

Start reading about the sixport actuation fix... go get a Haynes manual for the FC, its got lots of pictures in it.

Take your time, keep asking us questions... I know it seems like rocket science, but its not! Just don't be in to big a rush!!

I can't give ya pics cause i have a TII and it doesnt have anything of the stock exhaust system left!

Do you have Emissions testing in your area?????

live in columbus ohio and from what i know we dont have emission testing.

i get what you are saying but at this time and sence ihave had my rex the pick up tube is right by the second cat. right by downpipe. welded in. the tube is not touching any cat.

i was basicallly going to leave the two catsin teh front the two small ones. just take out large rear on right before the y pipe.

i did search, and this questions has not been ansered anywhere i have been. and going down to one muffler instead of two should add back a bit of backpressure right?