2000 Chevy Silverado 4.8 Ext Cab Short Bed (4L60E)

K&N Intake
Flow master Exhaust w dual outlets before right Rear wheel
MSD Wires and AC Delco Iridium Plugs
Corvette Servo
New air check valves /pulleys / belt / intake gasket / knock sensors

141,xxx miles

Recorded about 14.8 mpg just doesn't seem like that's what I should get.

Now I'm thinkin about installing some 1 5/8 long tube headers, and deleting the egr's and cats.. Then going to black bear in San Diego and getting a 91 octane tune..

Are the headers worth it before I get the tune? I can get them for $400 ceric coated from my brother and then have a muffler shop fab up a Y pipe to connect my flow master.. Just wanna hear some opinions and reviews before I start wasting time and money on headers and a y pipe.. I'm doing the tune regardless.. Thanks!

 

If you're looking to get more mpg, spending the extra money on headers and a tune may not make sense. Tuning may squeak out a little more mpg's.

As far as performance goes, long tubes are a great way to go and yes, you would have to get them tuned. Justin at Blackbear is a great guy to deal with.

You could also look into LPP headers. They are pretty decent imo for the price and you can get them with an ORY that will bolt up to the factory cat-back flange if you still have it. They are a sponsor on this site and you can find their information in the right sidebar.

 

cal speed and speed engineering have cheap options too. I think TSP has some as well, could be wrong

 

I went with the Texas Speed headers for my truck since they were running a $299 sale on their stainless steel 1 3/4"

As for MPG is the 14.8 all highway, city, or mixed? I know my dads 2000 ecsb with about 200K on the clock got about 13-14 mpg city and maybe 20 on the highway. Not sure you can expect much better than 14.8 if that's mostly city driving.....

 

I went with pacesetter ceramic coated found them online for $340 free shipping. I assume your truck has 3.42 gears? if so by far the best gear for max mpg effort on the highway. What size wheels and tires?

 

Wheels and tires are SS 20 x 8.5 on 285/50/20

What all do you guys remove when installing lt headers? Egr smog stuff?

 

The big heavy tires and wheels explain the gas mileage (or lack of).

 

Ditto on the above. I put 20's on my truck and saw a 2-3 mpg decrease. After a few months of paying for that and it having to come out of OD to pull a hill I put the 16" stockers back on......

 

The 20s shouldn't hurt highway millage, if anything slightly help it due to they make the rear 3.42 gear more like a 3.23. They do hurt mpgs on acceleration, take more power/fuel to get those big 80-90lbs wheel turning.

You might gain 1 to maaaaybe 2 from headers and tune. LT give a nice tq bump down low which should help get the truck up to speed a little quicker resulting in slightly less fuel being burned.

 

My truck in the sig stock got around 14 city and 18 highway with stock 16" wheels, after boltons, cam, and 275/55/20 I get around 16-18 city depending if I drive like a grandpa or have my foot in it some, and around 20-22 highway between 60-80mph.