Opinions, notes, comments etc. on headers

[Longhorn321]

OK I know a lot of you have installed headers and I know the principals about why they are better. What I want to know is how much better have you witnessed and in what way? Better power obviously but is it like night and day just from switching to headers? How about fuel economy? Like I said, I understand the principals but I have never actually done it and I know you have so gimme the benefit of your experience please.

[Blue_71]

on my 89, which is the only truck ive drove extensivly with manifolds and headers, the headers made it WORSE. lost 2 mpg, no low end power, ran lean... they're also a PAIN to get to some spark plugs.. get them to close to the floor, and it'll be nice and toasty too..

can ya tell i dont like headers anymore???

edit: i didnt think about it, but i have ran the 69 with two different sets of headers.. one set of 3/4 length large tube, and one set of full length small tube. the full/small tube headers had more low end, the large 3/4 ones had more top end

[whatnow123]

back in high school we installed headers on my buddys 69 camaro 307. We went from manifolds and single exhaust to headers, short pipes and two mufflers, it was a night and day difference and it was hard to believe it was the same motor.

[1968SWBBigBlock]

The most common mistake with headers is going to large tube style headers.
As a general rule street driven trucks need smaller dia tubes to maintain the scavenger effect.
This may change if you have a mountain motor.
Spend the money and buy a pair of ceramic coated headers, they will look and work much nicer than painted headers.
If you choose the correct size you should see an increase in performance, gas mileage, and cool factor.

[crazy longhorn]

The longtube headers I have run have always been an improvement over stock exhaust. on a street driven sb, I like to run an 1 5/8 primary tube(327-383), maybe drop down to a 1 1/2" tube (283-307) for best tork. The 406 can probably run a 1 3/4" tube without any loss in low end grunt. You will notice bigger gains on a hopped up motor, than you will on a stocker tho. Also watch the ex pipe sizing 2 1/4" dual is plenty for a mild 350, where you are better off with a 2 " pipe on the smaller cube motors. An H or X pipe in the system will also help with low end tork/mileage. crazyL

[MrBeast]

Originally Posted by crazy longhorn

The longtube headers I have run have always been an improvement over stock exhaust. on a street driven sb, I like to run an 1 5/8 primary tube(327-383), maybe drop down to a 1 1/2" tube (283-307) for best tork. The 406 can probably run a 1 3/4" tube without any loss in low end grunt. You will notice bigger gains on a hopped up motor, than you will on a stocker tho. Also watch the ex pipe sizing 2 1/4" dual is plenty for a mild 350, where you are better off with a 2 " pipe on the smaller cube motors. An H or X pipe in the system will also help with low end tork/mileage. crazyL

The setup I favor on a street small block is 1 5/8" primaries, and 2.5" exhaust, with a 2" cross pipe. Set up like this with a good full leingth exhaust, and you will have a good flowing ballanced exhaust that will keep right in tune with the engine, I know on a truck I built in highschool, addint this setup to it over the stock exhaust got me about 2 miles to the gallon better, and it really freed up some power.

Really I think putting anything larger than that on a small block in a street truck is just silly.

[Longhorn321]

Thanks guys. Good advice so far...keep it coming. The more people I hear from the better.

[chevguy7]

This is all good advice. What are your opinions on running headers with a 2.5" collector vs. a 3" collector and then using a reducer to go to 2.5" pipes?

[67_C-30]

The header brand and construction you choose is very important if you want a leak-free set-up. A cheap header with stamped thin flanges are going to leak - sooner usually than later. A good brand 16 gauge header with thick flanges with the ball socket type collectors are the best way to go, but you pay for what you get. As crazy longhorn said, the gains on a stock engine are far less significant that on a stock engine a modified one. You won't a night and day improvement with just a header change.