Another exhaust question

[bcrosson92]

1990
stock exhaust except i will be putting a flowmaster super 44 on soon. should i do a highflow cat? i have a speture cold air intake. and i will eventually change my header cause its cracked. it has putty on it now just to pass inspection. my main concern is will a high flow cat make my back pressure too low. i dont have a muffler on right now and it "SEEMS" like im missing torque. will a high flow cat and free flowing muffler make it run like it is now with out the muffler? how about after a new header and front pipe?

[prerunner1982]

Honestly not sure I would worry about a high flowcat. To me the outcome doesn't warrant the cost....

[bcrosson92]

im probably gonna change the cat i just wanna know that a high flow wont make me loose torque.

[4.3LXJ]

No, if anything you would gain

[bcrosson92]

ok. so now the exhaust header can i use a 91 and up header on my renix? and will all this be ok with the way it runs? does the ecu adjust to the free flowing exhaust?

[4.3LXJ]

The typical XJ exhaust is not free flowing. It is true you have a short header for an exhaust manifold. But that bend and pinched pipe make it somewhat restrictive.

[bcrosson92]

i know it isnt but it will be with the new cat and my muffler and a header if i can find one.