First off, am I able to tell if my truck has a cat without actually looking under it? (Basically I'm lazy and it's midnight so I don't want to go lay down and look) On the VIN check that was run, it has Federal emissions and Federal/NY/VT Emissions listed as option codes. Do only California trucks of the 2003 model year have cats?

Second, now comes my real questions. Say you have a California truck with a cat, and you get a cat back exhaust, will it help with EGTs? Say you have a federal truck, and you get a cat back exhaust, how would this work if you don't have a cat? Would the exhaust you buy come from the downpipe back? If it does, and there is no cat, I would imagine that this would be optimal for lowering EGTs, especially if you have a chip!! Am I sort of right, right, or not even close?

Pardon my ignorance, I'm just trying to figure stuff out!!

Have a good one, thanks!!

Dan

03 California trucks have cats. Replacing the stock muffler with something less restrictive will drop EGT's some.

In the engine compartment is a sticker, usually on the airbox that will say CATALYST if so equipped.

Doing this might help:

BANKS cat-back:
http://memimage.cardomain.net/member_images/1/web/781000-781999/781637_7_full.jpg

MBRP frontpipe:
http://memimage.cardomain.net/member_images/1/web/781000-781999/781637_19_full.jpg

ddp127- Getting rid of the muffler will help reduce egt's. Going with a 4" cat back system will reduce egt's even more. Since you dont have a cat, you could also go with a down-pipe back system which would include a 4" front-pipe. This setup will offer the biggest drop in egt's. Let me know if I can help with anything.

Thanks guys. I'm thinking right now. It will be awhile before I actually go and do anything.

Thanks again!!

Dan