Just picked up a 2007 LT3 this weekend, GM Certified w/ 43K miles. Sold the wife on adding some "fuel saving" performance mods to help it breathe, perform & sound a little better. Was looking to do a CAI, tune and exhaust. Suggestions on what's proven to give the best results? How restrictive is the exhaust (haven't actually inspected it that closely yet) and would more gains be had by adding a set of headers vs. catback for starters? Thanks.

 

Unless you're planning on internal mods to the engine, don't waste your money. Check out Blackbear Performance for a custom computer tune.

But I do have the GM Performance catback system (price in signature) from my 2007 that I'll sell you. Sounds great! And the butt dyno said it was good for a lot of extra ponies.

 

I'm certainly not doing any internal mods. So basically you're saying the factory intake and exhaust are efficient enough that any bolt-ons are a waste of money and a tune is the most effective mod. I'll check into the tune. You're exhaust for sale is off a Tahoe w/ a shorter wheel base, would it bolt directly on or would I need to extend the intermediate pipe or other mod to it for it to work?

 

I think you have the right idea of a CAI, tune and headers with exhaust. If you just add a cat back you won't get any extra power, just sound. I have always been a fan of adding headers - the factory manafolds are so restrictive this usually makes the big V8 breathe a lot better. Talk to Justin at blackbear and see what he says about adding a tune to a factory truck and if it is easy to adjust after adding other parts or if you should do it all at once.
but as others have said and will say the tune by itself is probably the best bang for your buck. the stock tune especially the transmission tune is very "easy going"

 

That's what I was thinking. I recently did a lot of mods for my brother inlaw on his '05 Mustang and the research I read was that a catback produced no additional power and to start with an off-road h-pipe and/or headers. Obviously I'm not removing the cats from the Burb but figured a set of headers had to help. Same for the tune..that gave us the biggest improvement overall...until the Paxton SC that is. Thanks for the input. Was underneath the truck this morning and the exhaust looks like it's 2.5, maybe 2.75 in diameter so may just add the resonator eliminator tail section and do headers, cai & tune.

 

It was late and I failed to notice you had a 'burb. The system is 2.75" and any competent muffler shop could fab the necessary extension for you.

Do they make headers that are short enuf so the "pup" cats are close enuf to the heads to lite off properly?

If you go w/ a Blackbear tune, probably easier to mod first and then tune. You may want to consider getting a second ECM for the tune so if you have to go in for service, you can put the stock ECM back in so they don't reflash your's w/ the tune. Also a tune might affect warranty claims.

Part of the seemingly doggy reaction to a WOT launch is the torque management system that doesn't allow the throttle to open all at once. Justen can fix that. Of course the reason for it is to protect the drivetrain and allow the 100K warranty.

 

I would also like to remove the rear resonator to clean up the look. if you do this post some pictures and what exhaust tip you ended up with.
good luck and let us know if you do anything else.

 

Check out the SLP resonator replacement w/ the dual tip side exit. As soon as I can find some time and put mine on, I'll take a picture.

 

I ordered mine yesterday...$99 w/ free shipping. Cheaper & Easier than making my own!

 

Good advise so far. The stock intake, cats and exhaust are sufficient and aftermarket parts have not yielded much hp gains. Although I did install intake and exhaust for sound. BB tune will be the best bang for the buck.

As far as headers, so far those that have installed aftermarket ones reported minimal gains but I recall those were for shorties. I wonder if long tube headers would have been better.