Extractor - Do they really work

[Sky8807]

One of the components that are popular here is the exhaust extractor or header. Wonder whether they really give you the improvement and increase hp as claim by some manufacturer.

 

Anyone out there can confirm that they really works and have some facts or comparision to prove it before and after fitment. Comparision like their o-100 timing, top speed, acceleration during cruising, fuel comsumption improvement, engine temp changes and so on and so forth.

 

Would like to hear some comments and feedback from those who actually measure the improvement rather than hearsay or quote from somewhere.

 

Open discussion to all.

[Pisces69]

I guess the term increase power is not so accurate here.

 

What the extractor does is to balance the power frm all cylinders so as all cyl r working smoothly, u get a better flow of the power.

 

The design of the extractors can alter the back pressure which affects the power band n torque of the engine.

 

Sometimes after fitting an extractor u might feel the car difficult to drive as the characterists of the engine has been altered. This is what engineers make use of to prepare a car for different driving conditions.

 

Remember that many other factors have to b taken into consideration when u alter one item as it usually affects other related parts, so if not done correctly, u may end up with a car which is slower than b4 the change.

 

Above is a very basic idea of what extractors do.

 

Maybe some of the other bros have more to add to this.

[Sky8807]

Many header maker have claimed improvement in hp and torque for the engine. And with a full exhaust system the improvement are more substantial. So I have to give then the benefit of a doubt.

 

"What the extractor does is to balance the power frm all cylinders so as all cyl r working smoothly, u get a better flow of the power."

 

Another way of putting it is exractor help improve exhaust scavenging, thus reducing the amount of exhaust contamination in the incoming air/fuel charge. With proper tuning of the piping and collectors the exhaust gas flow smoothly and thus power is not lost but rather engine is more responsive.

 

The design of the extractors is important and one should not just get any extractor in the market without finding out whether it is suitable for their engine or driving habits.

 

There are many imitation out there, the length of the primary pipes, pipe dia and thickness, collector size are all calculated and experimented before the best and correct extractor is made for a bolt-on for your car in the market. So for those who want to improve their engine response, don't just buy any extractor available, need to find out first that the extractor really works for your car. Because it is a bolt-on type, important consideration for bolt-on unit is when bolted onto you exhaust they should be leak free.

 

Using the wrong type of combination may make your car go slower. Eg like installing a 4 into 1 extractor setup and driving at mostly mid to low rpm may be wasteful because this setup works in the high rpm range.

 

My opinion.

Edited February 7, 2002 by Sky8807

[Pisces69]

Ah, yours in more detail. Much better.

 

For the part about more power, I guess it can b said extractors increase the power to a certain extent, but their main function is to balance the power from all the cylinders but this term dosent sell as well as ''more power''.

 

Generally to get more power u either get a bigger engine or turbocharge it.

 

Normally engine manufactures play with the power band to give an impression of more power but the max hp is still the same, just the torque curve has been altered.

[Sky8807]

Power increase is only marginal, for a big cc car, say above 2000cc, the difference is more obvious. as compared to a 1.6 and below.

 

When u fit extractor, next thing is the intakes need improvement, then comes K&N filters or the likes to maximise the performance.

 

So look likes one thing leads to another and $$ involved again.

Edited February 7, 2002 by Sky8807

[Torquelover]

I have heard many disc revolving ard the theory that if the exhaust system is too free-flowing, low-end torque will be affected? Any comments?

 

But if the exhaust is very free-flowing, shouldn't the exhaust exit from the combustion chambers more easily? Thus improving revvability (dont think there is such a word, but guess you guys know what I mean)

[Sky8807]

You got the point there. For those who want fast pick-up, and the boy racer or dragster type, a little loss in low end torque is a small price to pay. what we wants from extractor is free revving and shorter acceleration timing from the car.

 

Most probably you will be revving in the mid to high rpm range most of the time, except for cruising and relax driving where the slight drop in torque is insignificant.

The theory of the exhaust gases escaping fast also mean the intake charge are able to go in the combustion chamber fast as compared to standard. That mean fast pick-up and engine willing to rev easily.

 

For me, i have tried fitting extractor b4, and find it enjoyable revving the engine and experiencing the engine rpm increase and the car zoom. Good extractor give a smooth transition of the rpm all the way to hign rev and give you a feeling of satisfaction of a willing engine. That was the car era about 10 years back where carb was the main fuel control machanism.

 

Today, most of the car are well tuned and extractor give little benefit as compared to re-chips and ECu upgrade. Electronic era leh.

 

Fitting extractor plus full free flowing exhaust, its illegal, may give you an advantage over the others if you are serious about fast pickup..

[Hitman]

Personally I'm a big fan of extractor mods and replacement from the original.

 

Back in 1999, I switched my Toyota Celica to a full race mod in different stages as I needed the car. So under original specs, the extractor and exhaust system went first. With this change only, the revs were smoother and pick-up improved tremendously.

 

The only setback, the sound of the engine roared and caught unwanted attention. But yes, the car was better in all respects till all mods were done.

[Turbobrick]

Did U loose considerable low end torque with the extractor? What's was the extractor setup? 4-1 or 4-2-1?

[Mondeo]

Just want to know, does anyone car using 4-1 ?

[Sky8807]

With full race mod, the noise level when rev definately can tell.

With extractor and intake filter change the noise is only slightly higher when rev and if you put in the full exhaust system, noise is louder and if muffler is not catered for road use will be louder still.

 

Another notion is when u do mods, u tends to revs more than b4 so that u can check the improvement. Sometime, when we drive aggressively on standard engine configuration, the car can also responds quite satisfying as though moded. Of course with $$ put in to improve performance, we tend to agree with our mods as long as there is a slight improvement.

 

With only extractor, power is only increase slightly and not significant. But I believe as the rev pick-up, it tends to moves freely past the half (of max rev) point. So there may be some shiokness in revving in the higher rpm sector.

[Hitman]

Extractor was 4-2-1 . Basic adjustments was done by TRD and extractor was a TRD developed system - culminating to the exhaust system.

[Turbobrick]

Well with a 4-2-1 you'd still have the essential low end torque for SG driving conditions compared to a 4-1

[Guyver]

From what i know, 4-1 extractor is quite hurtful for the car.....but it's good for fast pick up. 4-2-1 extractor is better.... more balance... so u decide. = )

[Magfocus]

4-1 should be for high rev applications like civics. For normal cars, 4-2-1 is better without losing too much back pressure

[Dagger]

it's true that 4-2-1 extractors are meant for improving your low end...... while 4-1 is for high end....

 

for my car, power normally kicks in after the 2.5K rev mark...

 

 

.........but definitely a car to have a soft noise level, and shoots like a bullet....

Edited March 27, 2002 by Dagger

[Sky8807]

Both 4-2-1 and 4-1 are suitable for our Sg road usage. As for which is better, it's all depend on your car engine design or configuration.

 

But the ultimate is 4-1. Comparing both standard engine and try out for accel and pick-up and top end, 4-1 should win.

 

Low end torque comes naturally for big cc engine, for small and medium car, low end torque is only adequate and not in abundance. What you need is the car accelerate smooth and fast, that is the rpm climb and climb and the car zooom.

 

Extractor serve to give free flowing of the inlet and exhaust gases rather than giving torque. With the improvement in the intake and exhaust you engine rev faster and at the same time able to squeeze more of the 'charge' and thus have more horses, torque and power.

 

When the rpm speed up the flow of the mixture into the engine cyclinder become restrictive and less are able to squeeze into it because within that split second the the charge must get in. That where the extractor and exhaust system comes in.

[Dagger]

yeah..... thanks for the info...... all the while, i thought that 4-2-1 was better for low end....... but now i know that i'm wrong.....

 

but finding it weird why everyone's telling me that changing to 4-2-1 is better for low end.....

 

right now, i've changed my stock extractor (1.6 inch) to 2 inch 4-2-1, with my 1.6 inch pipe, and a remus S-shape muffler box, and twin exhaust.

 

Any recommendations to help gain low end torque??? like changing the piping to 2 inch too?? or change extractor to 4-2-1 (1.6 inch)????

 

Really would appreciate all help... thanks in advance....