Okay, so let's say I want to redo the exhaust on a car and want it to pass emissions. Here's what I want: Borla Pro mufflers, stainless steel tips, new cats (it's going to be a dual setup) and 3" aluminum pipe from the headers to the tail. This is NOT ON A CAMARO, btw. It's a side project car (just a little old 74 datsun 260z). A few questions:

1. Is it even acceptable to use galvanized steel against stainless steel tips? It's just so much cheaper that I wouldn't mind it for the extra $400 savings.

2. If I get a good cat, will I have to worry about passing emissions? Can you go TOO overboard with a catalytic converter?

 

What motor are you using in this? I assume it's either an LS or LT under the hood. And if it's a 74, why are you concerned with emissions? Here in Ohio, any thing older than 25 years qualifies for historical plates, and is not subject to emissions testing even if you don't get the historical tags. I mean technically, if a powerplant from a newer vehicle is placed into an older chassis, then the motor must retain all emissions equipment that was originally installed in the model year said motor was produced. But no one seems to adhere to that, nor do they appear to get any flak for doing so. As for your question on connecting aluminized pipe to stainless tips, there's no problem, as long as you are clamping, not welding, them together. Not sure on the other question, but my gut says you can't "over-cat" a car.

 

I'm using the stock 74 inline 6 motor for now (yeah, I know....cool!!!!). B) I will be putting an LS1 in it later, though. But yeah, that's all I needed to know. Thanks!

 

No problem man. Good luck with your project. Those old Datsuns make some wicked sleepers with GM power. I've seen a couple of em at one of the local tracks and they haul ***.

 

I know it! It will be awesome once it's done. Probably going to pull a caprice motor and throw that in there. Once it's restored, autocross and dragging here I come!