[alias]

Originally Posted by alias

well dude go see his garage and you will know i mean

sorry trying to type fast

i mean go check out his garage at his home in hutchins road

specially check out his octiva and accord

[idly]

Guyz in one of the posts Psycho had posted it explained all about headers.... Fanatatsic read ........

I was planning to get one for my Zen vxi 2003 model. And i was looking for a header which satisifies the statement - "Headers with smaller, longer primaries will get you slightly better fuel economy and better street driveability"

Please let me know the header brands which statisfy the statement for a Zen....also appreciate if ZEN with headers owners share their experience

[Prashanth Hegde]

Hi all .,

Yesterday I got my MPFI Esteem fitted with complete free flow ( headers , straight pipe and end can ) and here are few things i have noticed after the modification .

The car sounds good ( more bass ) but i don't think there is any improvements in performance or may be its very marginal to get noticed !! and neither it harmed previous stock performance .

while getting free flow fitted i happened to observer the stock exhaust manifold and esteem stock manifold almost resembles the headers i have put only things that they are bit short in length . the stock manifold is also 4x2x1 and i also went for 4x2x1 free flow system.

now the question in mind is does this free flow system is worth spending ?
looks like the exhaust note makes you feel like you going fast rather then actually being quick and fast .

Has any one really tested performance before and after installation of headers ? if yes please post the results ( dyno or timing ).


Regards
Prashanth

[ananthkamath]

dont know about the mpfi esteem, but i remember the swift has a very good manifold design. its a fabricated rather than cast unit. manufacturers are leaving very little on the table for the aftermarket, and i'm inclined to think an exhaust manifold, atleast for this engine, is one of those components which leave very little scope for improvement.

[HPP]

This is a long thread but I skimmed most of it, there is some good info in here, but not all of it. In general, most production aftermarket headers are "OK". They are not optimal, but are not a disaster either. Reversion is an issue, as is back pressure, and many other issues having to do with fluid dynamics etc. A great header would have varied primary lengths and secondaries as well, along with different diameters from the port of the head down to the collector of the header, and after the collector for that matter. Making a great header is a VERY complicated thing, and is harder to achieve then making a nice turbo manifold. A GREAT header would probably cost more to build and design then a cheap turbo kit(which is a waste of time and money for street cars).

If I were all of you, I wouldn't worry to much about it. If you want a header for your car, buy one that seems to have good build quality and does not seem extreme in it's runner diameter(either too thin or too big). Other then that, you can choose whether it collects 4 - 2 - 1, or 4 - 1. 4 - 2 - 1 will give you a wider power band, and a 4 -1 will give you more up top(if I remember all the theory correctly).

[redfire]

Originally Posted by ananthkamath

dont know about the mpfi esteem, but i remember the swift has a very good manifold design. its a fabricated rather than cast unit.

Oh... but swift is a car which is moded in high numbers now a days. Every other swift has a custom / aftermarket header. So are you telling it's not worth spending the money for it? A neat header will cost you 7 to 10K and a days work. If the stock system is good and there's a scope of only a very marginal / negligible difference in swift, I might drop my plan to go for headers. But the owners of swifts with custom headers claim they have a good difference in performance.

[HPP]

Backing up a little of what I said, take a look at post 136 of the thread I am linking below. Take a close look at the diameter of the primaries to begin with, then notice it steps up in size at a certain point. That point was found through thorough testing by BMW and then it goes on to the collector. I'm sure after the collector is more size changing but we don't get to see that part.

http://www.team-bhp.com/forum/intern...-works-10.html

[n_aditya]

Originally Posted by Prashanth Hegde

.... esteem stock manifold almost resembles the headers i have put only things that they are bit short in length . the stock manifold is also 4x2x1 and i also went for 4x2x1 free flow system.

Has any one really tested performance before and after installation of headers ? if yes please post the results ( dyno or timing ).

Hi PH,

My guess is that since the OE header and the aftermarket headers are similar in design (except for the shorter length) the performance is not going to be drastically improved.

Was your expectation high? Normally one assumes that a header makes wonders in terms of performance but thats only the first phase in modifications. No offence, please dont misunderstand me.

4x2x1 improves the torque or in other words, acceleration is quicker. The power is delivered in low RPM's. Good for city driving actually.

Also let us know who designed the headers. The person should have good knowledge of the car and its characteristics so that a good header is designed to deliver optimum performance.

I have a 4x1 header which kicks in at 4000 RPM. It was custom made by Psycho (member from bangy). I have a straight pipe from the headers till the end can. The mid range and top end has improved to a large extent compared to the stock performance. I can tell you that the car shoots to a 100k's from standstill in approx. 10 secs or even lesser depending on the launch etc. Does 165kmph in third gear and i personally have touched 190kmph on the car and it still had the punch for more. BTW my esteem is also MPFI. City driving is a little painful as the power is lacking in lower rpm's due to the specification of the header... but i am not complaining.

Oh and i have no dyno results to prove how much power she is putting out now. Also please note that the speeds mentioned above are not true speeds but speedo indicated figures.

[Prashanth Hegde]

Hi aditya.,

As you said i had some expectation ( but not very high ) but then i really unable to find any difference in driving .
I got this headers from FRK racing and since i never driven any cars with headers earlier i really don't know whether there is some thing wrong in my car or this all i get .
Does installation of headers need a resetting of ECU by disconnection it from battery ?
I haven't changed air filters but replaced it with new one.

I some where read that headers should be accomplied with free flow filter to get max performance , is that true ?

ya one thing is for sure that it sounds very sweet and makes you feel like going fast .

[n_aditya]

Originally Posted by Prashanth Hegde

Does installation of headers need a resetting of ECU by disconnection from battery ?

I haven't changed air filters but replaced it with new one.

I some where read that headers should be accomplied with free flow filter to get max performance , is that true ?

Resetting the ECU is not mandatory as the ECU will "learn" the new readings, inputs, values whatsoever and adapt to the new setting, unlike a carb engine which needs to be tuned.

Again a free flow air filter such as K&N is not mandatory. But its better to have one with a header and FFE system.

Let me explain... header systems and free flows are designed to expel the exhaust gases as quickly as possible from the engine. Refer to earlier posts for better explanation.

In layman terms, having a free flow air filter is like having a bigger nose (to inhale more air) and bigger lungs (to accomodate that quantity of air). So a free flow air filter coupled with a header & a free flow exhaust will help in breathing more air. More air is sensed by the ECU and more fuel is pumped in. Combustion is faster and the FFE expels unburnt gases or exhaust faster.

experts like psycho can throw more light on your issue. send him a PM.

On a lighter note refer to the last line on ajmat's post here http://www.team-bhp.com/forum/732401-post2475.html