I have an 04 Monte SS Intimidator and have read alot of posts about upgrades and am looking at getting a downpipe and have a few questions. I am thinking about getting the bolt-in 3" off-road pipe from zzp.
How hard is it to install? Do I just unbolt my current downpipe and bolt-in the new one? Will a 3" downpipe fit the stock 2.5" exhaust? If I get the off-road downpipe will I be hassled or be reported for not having a cat if I ever need to get it serviced? Will I need an O2 simulator, Bung, or extension? Will a 3" downpipe make me lose too much back pressure/HP? What is interlock flex and do I need it? Do I need gaskets also?

Thanks everyone!

 

SS intimidator? Is that a canadian model? Down pipe? It's FI?

 

well if you get the downpipe...no matter which size you go with you should still have a cat on there...i would get a highflow one, then get rid of the u-bend...but keep the o2 sensor, and if you want get rid of the resonator...your check engine light will be on for a while..but the computer will relearn it...or it did with mine anyway...

i would go 3" downpipe, high flow cat, u-bend delete, resonator delete...and you should be good

 

Dont I need an O2 simulator for an '04? And how difficult is it to install the bolt-on downpipe? Does the stock downpipe just unbolt or does it have to be cut off?

saluteTOme: Canadian model lol, man thats not funny.

Thanks

 

i think they're just bolt on..but not 100% sure...and some people talk about o2 simulator's, and i was going to get one..then my check engine light went out when i disconected the battery and it never came back on

 

i think they're just bolt on..but not 100% sure...and some people talk about o2 simulator's, and i was going to get one..then my check engine light went out when i disconected the battery and it never came back on

 

Here is what ZZP said when I contacted them:

The pipe will bolt right on, you will want to replace the rear gasket, and possibly the front. It narrows and bolts right up to the stock rear flange at 2.5”

You WILL throw a rear o2 code. You can have the code removed from your pCM, an o2 sim will NOT benefit you, as 04+ have a newer sensor that has an additional heat sensor that cannot yet be spoofed. You would normally need an o2 extension, but there will not be a bung as there is no cat. You do need the interlocking flex. On an L67, you will not loose too much with a 3”, you would on an L36.
Good Info if anyone else was wondering.So it looks like I would need to get a zzp or milzy pcm to get rid of the O2 code.

 

<plug> Otherwise you can buy mine. I'm selling my Random Tech downpipe from 3800 performance. </plug> LOL. http://www.3800performance.com/Merch...oduct_Count=13

Ok, on the topic.I have the 04 Intimidator myself and used the above downpipe and it worked great. I just added headers and needed to goto a customized downpipe system - long story.

Now your options are either getting a high flow catted downpipe or gettinga straight pipe and getting a new PCM. Word of warning, if you go straight pipe, no cat, no resonatorand catback exhaust, the police MAY be very interested in your vehicle as it will be loud. Depends onthe police in the area, they are jerks in my area - Ironically Harley Davidsons are fine.

Another point is if you have emissions standards to worry about. If you do, kick the staight pipe idea right out.

I was very happy with my last system - Random Tech downpipe above, kept the resonator, and Dynomax Exhaust. The reason I'm removing it is because I am upgrading my engine higher than originally anticipated and went with headers.

My Random Tech did kick out a check engine light every 3 months or so but I have a ODB2 scanner that quickly deletes it. This could have been also caused with other mods I had done as well. You can also get this cleared for free at Autozone.

 

I have a question, i just bought the 2.5 inch bolt ondownpipe with catfrom zzp. Will i need ano2 extension? or will i be fine and not need one? Im unsure. it doesnt say on the site that i would need one, and they are usually pretty good at telling you if you do on the site. just need some clarity, so i dont have any install issues.

Thanks

Gotta love black friday deals@ zzp!
polished valve covers, downpipe, upgraded ignition wires, and ceramic coatedfront powerlog!