Everyone says that long tubes make noticeable power and better fuel economy then the stock manifolds. My question is does anyone have hard numbers before and after headers for gas millage? I have the pace setters for my project truck but unless I hit the lottery it won't be getting finished this year again. One more tax return and she will finial be done. I have the headers sitting here and think I am going to throw then on the Tahoe. I would probably keep most of the stock system and probably add a muffler along with the headers. I want it to stay fairly quiet because I am always hauling the family.

The other question how much have you guys had invested in adapting the long tubes to the stock exhaust at some point? The truck is a 2006 Tahoe for those who don't know.

 

I lost about 2 mpg on the highway with headers being the only change. And most LT kits with Y will bolt right up to a stock catback.

Edit: This was after spending a couple of hours getting the tune dialed in and same driving habits. Also lost some low end with the LT's, and it's much louder in the truck (with dynamat).

 

Hey, I have a 2006 Tahoe too. I recently did the Airaid MIT, Pacesetter long tube headers, off-road Y-pipe, and tune. I only lost 1 mpg, but gained a lot of giddy up and go. I too wanted quiet, so I used the stock catback exhaust. It's a tiny bit louder than stock, but certainly not noisy. If you want to run cats, that will require a bit more work. If you get the Pacesetter ORY pipes (no cats), it's a direct bolt in. It does eliminate the rear O2 sensors which you have to tune out. Texas Speed has the ORY kit for only $140.

My install guide:

https://www.performancetrucks.net/fo...lation-500748/

 

is this bc you guys have your foot in the pedal all the time with the new mods? my truck gets better/same gas mileage now as it did stock. i just got 19 mpg on 22's with the cruise set at 65 and ac off a couple weeks ago. went about 300 miles up through new mexico. later i was going faster with the ac on so gas mileage suffered some then but at moderate speeds it does similar to stock, even with the mods. check your tunes maybe? better airflow and more hp means it takes less throttle to get to speed or makes it easier to stay cruising with the tc locked.

 

a set of long tubes will require some tuning to get the most out of them both for performance and efficiency...everything i've put headers on i've seen mileage improvements, not drastic but calculable.

 

I just put long tube headers (ARH 1 7/8" with Cats) and 4" mandrel catback on my 6.2L. Running with the stock exhaust I would get about 19 mpg at 65 mph. With the new exhaust i averaged 20.1 mpg on my trip last weekend running the same 65mph. This is without my Tune in the truck yet. I am hoping to pick up even more mpg with the tune.

 

If a truck is going from stock untuned to headers with a tune, there will more than likely be a mpg gain, but I would attribute that to the tune more than anything.

Some people gain mpg with headers, some don't. That is just the nature of modifying cars and trucks; trucks with identical cams, blowers, intakes, etc. have different results.

 

I got horrible MPG after my header swap. Only cause my foot was on the floor all the time

 

I always hear about people complaining about random noises after they install LTs...either like a leak or ticking noise. Is this true with y'all? I really want to get a set for my blown 2500, but can't make up my mind if it's worth it. I'll be running a stock 6.2 muffler and either a single 3.5 or 4" pipe

 

From in the cab, mine sounds like it has an exhaust leak. And I have two Magnaflows, a 22" big body behind a 7" round by 12". Just the 22" was way too loud for me with catless LT's.