intofocuszx3, Thanks for your info that is a nice HEADER on ebay. I have 06 hhr with 2.2 and plan on Trifecta tune, port&polish the head bbut realy needed header for it. Have you checked water injection system for add on? See aquatune.com seems like it would be realy nice. Thanks agin for info.

 

I agree..the BIG 3 know what aftermarket parts can do for milage.Yet............they don't!
Ford tried to do a header but they put so many bumps and dings in them they were almost useless.Amazing how a simple header install can make such a difference and nobody will factory them.If price is an issue,they have ways of dealing with that.Everything becomes cheaper over time.Less weight more power..but yeah..also more maintenance.Maybe thats it.The biggest obsticle?Politics!

 

Headers do produce more horsepower, torque and mileage.
There are some reasons why most manufacturors do not use them. They are more expensive, louder and more fragile, cracks, leaks and gasket problems. The car maker does not want any warranty issues for 100,000 miles or more.
Old reliable cast iron exhaust manifolds are more durable.
Right now I am thinking of putting a header on my car but I do not want more noise and I fully realize it will not last 50,000 miles with out having to change gaskets. I have had some headers that blew out every other month or so and certainly do not want that kind of problem.

 

:QUOTE=Ed Harvey;347092]intofocuszx3, Thanks for your info that is a nice HEADER on ebay. I have 06 hhr with 2.2 and plan on Trifecta tune, port&polish the head bbut realy needed header for it. Have you checked water injection system for add on? See aquatune.com seems like it would be realy nice. Thanks agin for info.[/QUOTE]

 

Ed, I think the AquaTune would be a total waste of money. The only way it would help (in my opinion) is if your car was designed to run 93+ octane and you were running 87. The water injection helps to cut detonation so it does not lose too much performance or hurt the motor too much. Still you would get much better performance, mileage and durability by using correct gas.
On my drag race car we record air temp, altitude and Humidity. (water in the air)
The higher the humidity the slower the car goes. Period. The water does not add anything to the performance so there is no reason to add water.

Headers can definatly help but are prone to gasket leaks and I do not know if it would be worth the trouble.

Porting and polishing the head I would say does not need to be done in fact would most likely hurt performance and mileage. Get a 2.4 intake manifold and exhaust system. Maybe a header and a Trifecta tune and your car will run MUCH better and get better mileage if you keep your foot out of it.

 

Porting and polishing the head I would say does not need to be done in fact would most likely hurt performance and mileage.


^^^^^^^verify

 

Curly1, Thanks for the info. Here's what I've always been told an engin is an air pump, more air in (2.4intake) more air out (header) duel exhaust, porting & polishing the head & header, upgrade the cam, wakes up the motor. As to water injection thats new to me and have been told to use windshieldwasher fluid instead of distilled water. Why would porting the head hurt performance? The stock exhaust manafold is so small how can it breathe? Is comp. 10.5:1? Thats high, but runs on 87 oct. is timing retarded? Makes no differance if I run all 93 oct. in gas milage.The header I found is all stainless and nice.

 

An engine is an air pump and for the most part more air in and out helps it. Now porting the heads and bigger cam is a totally different deal, open them up too much and it "stalls" the air and the fuel falls out. Worse than if you had not messed with it at all. Also head porting is very critical where you take material out and not to cut into water jackets (scrapping the head) or in the wrong place to make it worse.
The factory head is more than good enough for much more horsepower than it puts out stock. You would spend a lot of time and money and most likely make it much worse!
With a larger cam it will make more horsepower up at high RPM 7500 to 9000 but at the cost of low RPM horsepower. Drive around and look at your tach, where is the RPM most of the time? That is where you want to increase the horsepower (and mileage).
Bigger intake manifold and filter will help, larger exhaust and getting rid of factory muffler will help. Porting and cams will hurt everything below 7000 RPM and you would have to change torque converter, gears and do a tune to get rid of rev limiter to run over 7500 RPM. If you did the porting, cams and tune the gas mileage would be terrible and it would be so loud and expensive to drive you would hate to get any where near it. On my race car I have a 5500 RPM stall convertor because it makes NO horsepower under 4500. None, Nada, Zero, Zip. Do you want a car that you have to have at 8000 RPM just to get out of the driveway?


First off I think the water injection is a total waste of money. And if you do it anyway do NOT use windshield washer fluid! You can use water and some alcohol (alcohol is in washer fluid to keep it from freezing) but the other stuff they put in washer fluid is not good for your motor. In a best case the water injection is a bandaid cure for other problems and it creates some new ones of its own. Just dont go there and save your money.

Headers work good for race cars but most everyone made either leaks, burns the spark plug wires or just wont fit right. They are all louder than stock. Now with that said I am thinking of doing a header myself but not sure if it is worth the hassles. They do make more horsepower but you may have to tighten the bolts every month and stay on top of them to keep them from leaking. They will not last 100,000 miles or more like the original cast iron exhaust manifolds. If you want a good performing car with few problems keep the stock exhaust manifold. You can get better performance and mileage if you are willing to put up with the problems of headers some worse than others.

The way I am doing it and I think it is best is to put a 2.4 intake manifold, a 2.4 exhaust with a Cherry Bomb Vortex muffler and an Airiad intake filter assembly on there. I am going to do a Trifecta tune and an underdrive pulley. Now what I am expecting from that is about 5 MPG better in the city and 10 MPG better on the highway. And of course it runs much better to. To be realistic my car will never out run Corvettes but it will out run other HHR's and get better mileage to when I am done.

Basically you want the motor to breathe but you do not want to mess with the internals of the motor. The factory intake and exhaust is set up to make these cars very quiet and that means restrictive which hurts performance.
Eliminating the restrictions will give you better performance with out raising the RPM of the powerband. Once you go internal cams porting etc for every 2 Hp more you make you will lose atleast one down low. If you do not have enough air and fuel to support the larger cams you will lose it down low AND up top! If you do not have enough convertor, gear ratio and traction you would never get any where anyway.

 

well said.

 

LOL, if I were a header I would want to be made out of cast iron. I want to live forever though :) If you are concerened about mileage, adjust your driving, not your car. I'd take a hint from some of the fast HHRS and Cobalts and Solstice/sky owners. If its speed you need don't waste time...just get boost :), no water, or noodle piping, or porting/polishing. Just get boot and forget the other wallet emptying devices.