oblio98

What would the "new look" forum be without another "headers" post. Here goes:

1) Will (Comptech) headers cause the engine to age prematurely?

2) Why don't the auto manufacturers make the stock exhaust manifolds more like headers? Are they that expensive to make?

3) Since the headers cause the exhaust gas to "free flow", does this make the engine more efficient (increase gas mileage) [Not counting the fact that the driver will stay in the VTEC more often! ]

4) Does the engine run hotter with headers?

Thanks in advance. I'm sure most of these were asked in the past at some point....

:-jon

Mr Hyde

Hey Jon if I answer these ?'s will you give me a ride in your car on Sunday to get a feel of the springs affect on the ride quality??? Unfortunately my headers wont be here in time for me to offer you the same courtesy. Hopefully the sways will be though. I ordered em both this past weekend.

1. No it shouldnt unless you suddenly get a heavier foot now to get a better feel of those gains the header will give you. Actually they should do the opposite. The headers dont give you more power by really doing anything they are just uninhibiting the engine less than the OEM ones, so the engine is now expelling less energy to get rid of the exhaust gases.

2. Cast iron manifiolds are much much much cheaper to make than the stainless steel Comptech ones with those smooth bends. For the general public that doesnt know what a header even is, the manufacturers wont bother with the increased cost which would get pased on to the consumer.

3. Yup MPG's should go up, dont expect drastic gains, but there will be minimal gains none the less, maybe a couple mpg's more.

4. Underhood temps may increase a little at idle since you will be getting rid of the heat shield, but when the car is its a mute point

dj5

I just purchased my black/parchment TL-S on June 30 and have been interested in the possiblity of replacing the stock headers with Compech headers if they gave a significant (20 +) increase in hp. Based information that I have gather so far don't know if they are worth the investment of $1200.

Check out this web site on dyno results from adding headers to a 99 TL.

http://www.comptechusa.com/images/dyno/1999TLplot.pdf


Would appreciate any other comments or insight on wether to replace or not.

Road Rage

1) MPG's will be mimimally affected, certainly not several MPG. A fraction at best. The headers do not affect normal crusing speeds in terms of torque, which is the prime issue in accelerating to speed, and thus the determinant of gas mileage.

2) Underhood temps are not an issue. Stainless steel retains heat better than cast iron so my guess is this is a tradeoff at idle, and no issue when the car is moving.

3) It is not just the smooth bends that provide horsepower - it is the scavenging affect of the collector, and the equal lengths of the tubes. It is expensive to build these headers - the cutting and fitting are labor intensive.

rockinTLS

The link below is to the dyno for a 2001 CL-S which is the same engine as our TL-S. Results are max 32 HP at the wheels, which translates to approximately 40 HP at the flywheel. I have also attached a link to the CL-S forum in which one of the members had their own car dyno'd with headers.

http://www.comptechusa.com/images/dyno/2000CLSplot.pdf

http://www.acura-cl.com/cgi-bin/ulti...c&f=1&t=003166

I am seriously considering going to headers myself. Just have to save up the $$$. Even though the results are all at the higher end of the powerband, they seem pretty significant.

dj5

Any other comments on if Comptech headers are worth the $1200-$1300 investments.

Mr.T

Worth my money. But Mr.Hyde I heard that without the heat shield the fan will burn out. Of course our cars are different from others like for example the honda crx or civic which there fans did burn out. So should I be safe and custom a heat shield or leave it alone to scare off the rice rockets

Mr.T

EricL

They give you a nice kick-in-the-pants from 5K to 7K. The boost down lower is not that significant.

Mike (they guy whos dyno is shows with stock, headers, headers and cai) got a better 1/4 mile time with SSR Comp wheels.

I'm not telling you to NOT get them, just what to expect -- they work great with a cold air intake and extend the torque curve upward.

The stock manifold is a piece of junk with gas doing right 90 or 180 degree turns -- not the stuff of good exhaust design.

AS Road Rage correctly stated, you at least get good pulse extraction from the comptech headers. They are also stainless steel. I had a bunch of mild-steel headers break on my Bimmer (they were NOT ceramic coated).

I have the light wheels, headers, and AEM and the car flys...

(You get what you pay for!!!)

bricot

I had the headers installed, I don't regret doing it. They do give you a little quicker pick up when you hit the VTEC range. It also seems to accelerate much smoother.

edgalang

I would assume that the headers for the TLS got upgraded slightly from the ones in the TLP since it got 35 more horses. If they both have the same exhaust manifold, where did the extra 35 horses come from?

EricL

The MAX gain is actualy just 24 HP. I define MAX (and so do every non-shady dyno operator, car magazine, and pro) as the highest level reached. The stock CLS reaches 208 (see the pdf) file and the after header install shows 232. 232-208 = 24HP gain at the front wheels or 30 HP gain at the crank (assuming a 20% loss). (This is why you will see people use handles like -- 290HP, etc.

The proper way to find the MAX gain is:

MAX(data_set2) - MAX(data_set1) = MAX gain.

The other BS about peak gains is just a way to confuse people, the headers with the better flow extend the torque curve and the stock torque just falls off before the header torque curve does (have a look).

EricL

Same headers for:

Accord
CL-P
CL-S
TL
TL-S

The headers are the same for all of the above listed cars!

The increase in power gain is related to the increased volume of air that the higher output -S engine is producing. The -S versions also have less restrictive mufflers that would only enhance the operation of the header.

When an engine is flowing a ton of air and it is more biased toward top-end power making (the S has different cams too), any increase in volumetric efficiency will be rewarded in a big way.

(There are lots of other issues, but it is the same header...)

edgalang

thanks. so i guess it would be safe to asume that the comptech headers are the "best bang for you buck" mod when it comes time to mod the TLS? I wasnt sure if it was since I wasnt aware that it had the very same headers as an accord.

EricL

Yep, it is the same as the Accord, TL, etc. I enjoy the power I get from 5K to 7K and the AEM helps too! I did get more across the board help from the 50lb lighter wheels (at least that is my opinion) and one of the CLS guys who was not running that great in the 1/4 mile (with headers and AEM) got down to a 14.3 with the lighter wheels (in addition to the headers and AEM).

I got the stuff from Tim (Snook), and really enjoy the mods.

dj5

I'm still on the fence about adding headers to my new TL-S.

From everything that I have read, seems like most of the benefit (20-30 added hp) comes at 5000-7000 RPM. Unless I plan to do a lot of street racing there would be little to no benefit in normal day to day driving.

For $1200-$1400, not sure it's worth the investment. Would like to hear more on the Pros and Cons of adding them.

Thanks --- also this web site is addictive.

FlyingPig

You don't VTEC in your everyday driving?
What a waste of a beautiful family car with a nice engine!

Road Rage

How many of you "Vtec 100% of the timers" actually own your cars as opposed to leasing?

Just curious.

moomaster_99

I own mine.

dro_15

I DO!!!!!! i love v-tec......

MikePA

Congrats on starting up a thread that's over 5 years old.

Phrosttz0

haha