360 Pre-Cats in the Headers

yes they can - i have seen an engine rebuild due to this ... this particular guy learned that when your check engine comes on bring it to the shop

 

According to my tech, this is true. Mine were removed after they began to loosen up a bit and rattle.

 

I have heard of this, but have never come across it at the shop. When the main cats go, they make a pretty annoying rattle, I assume that the precats would do the same, can anyone shed light on that?

As far as the check light, it won't always come on when a precat goes, the main cats are also monitered and in order for the check light to come on, the main cat would also have to let go.

 

Colby, they do rattle but not usually as much as the mains. The problem is by the time it is symptomatic it has usually done engine damage. For what it is worth we have never seen a precat failure that was not caused by a running problem and every one I have investigated had an aftermarket muffler. I know everyone who has experienced this is going to say "My car was running perfect and it still failed". Yea I know, and Mary got knocked up and was still a virgin.

As far as a CEL goes, functionally the word "Precat" is really inaccurate these days. It does serve as a main and the O2's monitor its function, not the downstream cat.

 

If I remember correctly, the European 360's do NOT have pre-cats in the headers.

Only 2 cats after the headers. I would try to source a set of European headers.

 

According to my techs also, this does occur. My headers appear to possibly have a crack (evidenced by intense burn marks on the heat shield at the 1:4 split site). I will be putting Tubi headers on in the spring.

Regards,
Pete

 

My car is a 99 Modena and it do not have the pre-cats on the headers. You should find a set of those and safe some money .

 

Dear Rifledriver-
I have a question regarding the Ferrari factory sport (CS) exhaust. I upgraded my 360 with this and per your advice have the vacuum lines properly connected.

Am I at any increased risk for a pre-cat failure compared to the cars that run after market mufflers?

 

Thats a good question. I really don't know because I have not seen any failures with that system. It does however deprive Ferrari of being able to blame a failure on an aftermarket exhaust which is exactly their first line of defense.

 

If new headers are installed that don't have pre-cats (either tubi or euro headers) does this affect the car by making the check engine light come on, or does it increase emissions or make the car more prone to failing DVM emissions testing?

What does the pre-cat do- if the car can be run with no emissions/check engine light issues, shouldn't we all just do a one-time upgrade to non-pre-cat headers right now or is it relatively expensive?

 

Most likely, they are for cold-start emissions. Placing catalyzers close to the exhaust will heat them up quicker, thus making them more effective the minutes after a cold-start.

They were a performance hindrance on my Nissan 300ZX Twin Turbo and a common mod was to replace them w/ straight-pipes or just gut them (to pass visual emission tests).

///Michael

 

do euro 360 cs headers have precats. any point /improvement changing to fabspeed/agency power sport headers?

 

What is a running problem?

 

do all 360 years have this set up?

 

Did your tech remove them and then just leave nothing there? Does your car throw any check engine lights (since that light is primarily related to emissions) with it removed? Have you gone through inspection yet- if so does it register anything in the DMV computer?

Sounds like this would be a great upgrade- to simply remove the freaking things!

 

All except 1999 model year...