whozizzit

Anybody hear anything about when there will be headers available? I figure it wont be for a little while but if anybody knows anything lemme know. Looked on Comptech's website and everywhere else but I came up with nothing. Looks like it gonna be a looooong time before anything drastic can be done with the TL.

Thorin78

If I remember correctly, the headers are welded on so you cannot change them. Do a search for it and you should get some info.

JDM5lugHatch

Well the factory "headers" are part of the block (being that they are casted into the block). However, there are 3 catalytic converters 2 coming off the block and one under the car. If a company would essentially manufacturer 2 pipes that connect to each side of the block eliminating 2 of the 3 cats you could probably see some pretty decent HP increases. I thought about taking the car to a custom shop to see if they would be willing to make a setup for it. The only problem is that most shops won't do anything where it removes cataylitic converters because it's against the law and their business could be shut down.

datplayaz

My buddy works at a shop and I'm trying to get him to invest some time into my car... I'm trying to do a lot of things with my car... But this has to be one my top priordity list

MichaelBenz

iTrader: (2)

Yep....he's right!.....

Schulminator

iTrader: (2)

does the TL have a pre-cat o2 sensor and post-cat o2?

Burgman

Yep, and the check engine light would stay on if you tried to run the car without the cats

speedracerIII

To avoid the CE light you could customize exhaust and weld bungs for the O2 sensors...

JDM5lugHatch

Pre-cat O2 sensors.

JDM5lugHatch

No because they are Pre-cat not post. With post cat O2 sensors you will need CEL fixes(resistors) to trick the ecu. I had a WRX with no cats and had to use CEL fixes because the O2 sensors were after the cats.

Burgman

Remember all OBDII cars (any car built after '96) have Pre and Post-cat O2 sensors to let the computer know the condition of the cats. Look close, our cars also have post-cat sensors.

subinf

Its just not worth it. I thought about building "headers" for my TL but the amount of time necessary to set up everything doesnt seem worth it. I dont want the CEL to stay on and I cant justify messing around with the integrity of the car before the cats. I'm all for modifying stuff, but this just seems like the amount gained is not worth the time spent.

Meek32v6

iTrader: (7)

..unless your a shop with some extra cash to purchase a TL, customize and get into a mag for publicity. It would be unique but so many other cars that would respond better when trying to mod. ( this is starting to sound familiar. Alot of people told me this when i wanted to turbo my D17 when they first came out, but I did it...might have to change mind in the future.)

encrypted03

Wait wait, you're kidding, right? They aren't bolt-on headers that you can swap anymore????

Pure Adrenaline

iTrader: (2)

I think you guys are taking the headers a bit too seriously.

They are just metal pipes. The point of aftermarket headers is to increase the exhaust gas flow, which is usually done with increased pipe diameter. Then you weld on a bung where the sensors originally were on the factory exhaust manifold.

So have a shop take off the exhaust manifold, bend some pipes and weld them onto some flanges, and weld a bung on each cylinder bank for the O2 sensors.

It's just a lot of work, but it's not that hard. Besides, why would you EVER want to get rid of the primary sensors? That's the sole source of air-fuel ratio data, which is vital in engine performance and maintenance. Without them, you will be running on a base map constantly which is not good, and that's if the engine doesn't go into protection mode.

You can get rid of the secondary O2 sensor which is in the catalytic converter (technically not "post-cat" because it is in the catalytic converter), but you cannot get rid of the primary sensors.

:2cent:

2_FastTLs

Does anyone here know what they are talking about? Headers are built to tune exhaust pulses, and to scavenge the exhaust ports. Increasing diameter is not the major factor in building headers, and in many cases going with larger tubes can hurt exhaust flow.

Pure Adrenaline

iTrader: (2)

For starters, length of the pipes affects torque, and the pipe diameter affects where your peak power will be. Through proper tuning and experimenting with different pipe bend designs. length and diameters, you can achieve maximum efficiency. However, that's not the case with all headers. A lot of them are not tested to the maximum limit/efficiency, and as long as they provide a good amount of gains, they are deemed acceptable; or to put it bluntly, "good enough" as long as it provides acceptable gains.

In a perfect world, all headers would be tested and designed to decrease resonance, resist cracking, and tuned to a perfect harmony while providing great gains. But we don't live in a perfect world. Like I said, it's not that hard to bend some pipes and experiment. And from what I've seen, especially on engines like ours with restrictive exhaust manifold design, going to a larger diameter seems to be the main factor in increasing gains. For instance, the small diameter of the stock exhaust manifold is restrictive, and the short and tight bend design dictates that it's not built for a high-RPM power peak. By going to larger diameter pipes and slightly longer length found on most aftermarket headers found for the J32A2 (very similar in architecture to the J32A3), the same should hold for the 3G engine. Do you think OBX tests exhaust pulses, the ideal pipe bend angles, length and diameter? I doubt it. Yet along with an intake and pulleys, OBX headers helped increase the peak power by 40+ fwhp on my car. They resonate, and they crack; their bias for high-RPM power sacrifices low end torque and power.... but like I said, "good enough". Our engines (J32A2 and J32A3 alike) come alive in the higher RPM range, and by doing some simple experiments (mainly pipe diameter to increase flow), we should see acceptable gains, albeit not at maximum efficiency. I know people who bend pipes to make their own parts, and although they don't have the equipment to measure flow rate and exhaust pulses like you mentioned, they still get some good numbers out of them.

I don't have a master's degree in pipe bending, though... so I don't know.

Thorin78

Someone could just buy that engine on ebay for $2k and experiment with it on their free time. But I agree with Pure Adrenaline, at this point, it's not worth it for a company to make a mod for this. Someone would have to cut out the pipes and re-weld it back onto the engine.

But then again, there are those HP gain chips that you can buy for $20 as well

Burgman

Headers are not possible on our engines. Most engines have exhaust ports at each cylinder thus allowing individual header pipes to go to each port. The new TLs only have one exhaust port per head; all the exhaust is already combined in the head. Basicaly the exhaust manifold is a molded part of the heads so it can not be replaced.

JDM5lugHatch

I believe I said that above.

Pro Stock John

Running without cats is always worth some power, cats are a restriction.

2_FastTLs

Experimenting!? I know of a few places who engineer a tuned header at 1st crack by using computer program along with cam profiles, bore X stroke, compression, port sizes, etc, etc. They tune the header design to match the desired effect before header is even built. Headers are a give/take part, but these guys don't need to experiment.

2_FastTLs

I don't think so. The TL head has ports just like every other head ever made. On TL the exhaust manifold is casted right onto the head. If you were to bandsaw off the manifold you would see 3 exhaust ports, then one could weld or bolt on a header plate.

Pure Adrenaline

iTrader: (2)

If it was that easy to design and make headers, then every car out there would have headers available.

So you know places who can use computer programs to design headers, cool... like I said, I know people who bend their own pipes based on know-how and experience, and their stuff turn out great. Perhaps not to the accuracy and efficiency of headers designed by computer programs and equipment, but those can be pricey, especially for mere car enthusiasts who work on their cars in their garage. We can't all be rich and go to a place to use a computer program and have a perfectly tuned header... good for you, though.

But you know, once again, I don't have a master's degree in a pipe-bending computer program, so I don't know.

Burgman

Sounds easy but normal engines the exhaust ports run strait from the cylinders to the side of the head. In the new TL the outer exhaust ports run at an angle from the cylinders to the center exhaust outlet so if you cut that part of the head off you would end up with a big oval opening.

True, just bringing up the point again since it looks like some people are not getting the fact that the exhaust manifold is part of the head.

subinf

I had the opportunity to remove all the cats and just build straight pipes from the head but still decided against it...just doesnt seem worth it.

2_FastTLs

I never said anything about fabrication, only the design. Each would need to be welded in sections using TIG. Each build is a slow process so they fit right, etc.

Burns Stainless in CA can engineer a header for cheap, then you use those specs to fabricate. http://www.burnsstainless.com/

2_FastTLs

There still is casting webbing between ports.

encrypted03

Yep, it does seem a bit far-fetched that they can do something, here's a pic I found of our heads:

SouthernBoy

As with most cars, our engines do not come from the factory with headers. And as has been stated, the exhaust manifolds are cast as a part of the heads, so headers are not possible with our engines.

One poster mentioned that the heads could be modified to the extent that headers could be installed, but this would be quite costly and something that you do not want to attempt unless your intent is to run your car in competition only.

To repeat, very few cars are shipped from the factory with headers, but there are more like this in the present day than in past years.

2_FastTLs

Cut that she-it right off with a bandsaw. Then let the fabrication begin, it's that simple!

MugenR

what if you just port and polished it and deleted the 2 cats from the head. and put straight piping to the third cat?

encrypted03

Exactly what I was thinking. I just purchased a set of heads, so I'll attempt that. Hopefully with the s/c it may help out

chill_dog

Noob question...port and polish?

MugenR

I found a good write up on Port and Polishing on Super Honda.

Here are some basics about port and polishing and cylinder heads.


Airflow basics- Getting good airflow through your cylinder head is a must if you want to create big horsepower. How increasing airflow gets you big numbers? First remember that your engine is basically a big air pump. To get the most amount of horsepower out your head, you need the max amount of fresh airflow into the engine and the most amount of burnt exhaust out of the engine, with the least mechanical effort. Extra intake and exhaust port restriction will create more work for the motor, the extra created by restrictive ports is called pumping loss. Look at is this way; if you suck a smoothie through a coffee stir straw it will be very hard to get any of that smoothie through that straw. If you switch to a larger straw you get a lot more smoothie with less work—life is better with big straw right? The extra work with the smaller straw, is the same as pumping loss. The more work that the motor has to do to get the needed gases in and out of the motor, means less hp for your wheels.

Volumetric Efficiency- Another huge factor is volumetric efficiency. Volumetric efficiency is the percentage of an engine’s displacement that is filled on each intake stroke. Look at it this way: If you have a motor that displaces 1000cc. If the engine can take in 800cc or air on the intake stroke, you motor has 80% volumetric efficiency. Your standard Honda motor has about this amount of volumetric efficiency. How you get this number is based on a motors port size and configuration to optimize volume and geometry. This is good for a stock motor, but when you want modify your motor for more power, your flow demands for that motor change as well. Your basic bolt-on mods (header, intake, exhaust and cams, some people don’t consider this a bolt-on but in my eyes they are) promote higher rpm operation also demand more airflow. Although not a must to get head work when your basic botl-ons are on your motor, they do like it more and will perform better with head work. That goes with just a stock motor, but you get the idea. More flow usually requires bigger ports and more cross-sectional area. The main effect of porting a head is to reduce pumping losses and increasing volumetric efficiency by reducing the restriction.

Porting- In the porting process the intake and exhaust ports are carefully reshaped (or should be if the porter really know what he/she is doing) by hand. This reshaping consists of enlarging, straightening, and streamlining to get rid of as much pumping-loss inducing restriction, turbulence to increase the flow velocity of the cylinder head as much as possible while make as much HP as possible. Most of the time ports are straightened by a die grinder and a carbide bit to a line of straight configuration. This straightening process gets rid of any bends that may cause turbulence in the head. This doe grinder that they use also is used to get rid of too cutting marks, sand casting pits, and usual bumps and lumps that are made by the mass production of our cylinder heads. Another process to gain more volumetric efficiency out of the head is called, extrude honing. This is where thick putty like goo full of abrasive is pushed through the cylinder head, enlarging the ports, just like the natural flow of your motor would like them to be. There are limits to porting though. You can make ports to big. Symptoms of a head that has been ported to much are a soggy bottom end, not making power. The other is a lumpy idle. The type of porting for your car will depend on the type of set up you want to run. Turbo cars like smaller port, high velocity ports without a lot of overall port volume. Nitrous and supercharged cars like the bigger ports with more overall port volume. The N/A street motors like the smaller, high velocity ports, like the turbo cars. Drag N/A motors will tend to like the bigger ports, this gets rid of the bottom end, but they want top end so it really does not matter.

Valve jobs- this is another major factor in getting the most out of your head. Truly, a 50% of head flow gains can be found in the valve job. Stock valve jobs are usually either one-angle valve job or two-angle valve jobs. One-angle valve jobs, is just done on the seats surface, two-angle valve jobs are a seat cut and a smooth throat cut. The high performance valve jobs have three-angled cuts, one on each side of the valve seat.
1st- there is a throat cut typically around 60-70 degrees. This will help the ease of the air’s transition to the 45-degree valve seat cut.
2nd- there is a 45-degree valve seat cut, which is literally where the valve actually seats.
3rd- this is called the top cut. This cut is immediately after the seat cut and is typically 30-20 degrees. This cut also helps to reduce valve shrouding of the airflow past the valve (or before if we are talking about the exhaust valve) as the valve starts to lift of the seat. There are five-angled valve jobs, but I think for the most part they are not needed, that is why I am not going to get into the five-angle valve job process.

Combustion chambers- another thing that should be looked into if getting headwork done is the quench zones of the head’s combustin chamber. The quench zone is the flat area of the combustion chamber where the piston comes in close proximity at TDC (top dead center). These quench zones promote more complete burning and the chances of detonation.

Milling- milling takes of a thin layer of metal from the bottom of your head. This creates a flat surface, which promotes a better seal to the block. This also increases compression. Most head porter will slightly mill the head, usually .050”-.060”. This increased the chances of piston to valve contact. Remember though depending on how much you mill a head will retard you timing anywhere from 4-6 degrees. To counter act this you should get a set of adjustable cam gears. Which most have, who are getting head work done. Since headwork is more saved to do when building a motor up. Piston to valve contact can be catastrophic to a motor. This can be done mathematically, but I highly suggest claying the motor. I did a write up on this you can find in the advanced tech and theory forum inside the N/A forum. Or go here to check it out http://www./forum/show...readid=126827..
It is important to maintain at least .045” on the intake valves and .055” on the exhaust valves. You want .030” clearance between any part of the piston and the cylinder head.

chill_dog

Wow, thanks for the info MugenR...technical, engineering type parts are over my head as I'd have to focus and think to understand them and I generally try to avoid doing that, but I get the picture. Where does one go for such things, and what does such an undertaking run (ballpark)?

JDM5lugHatch

You can go to any decent machine shop to get a basic port and polish done. You can also buy a port and polish kit if it's something you think you would like to tackel yourself. There is also the Extrude Hone route which is a good but expensive way to go as well.

MugenR

u know... i think we can do this pretty easily. port polish the head, have a shop make a custom pipe coming off the head into the 3rd cat... 2 - 1 piping. and since the o2 sensors are precat, just weld a nub to attach the o2 sensors on the new piping... and since most of us will not not have emissions tests for some time, this will be worth it i think. if you need an emissions test, just swap... not very hard, just some basic tools and a jack.

Burgman

You still have post cat O2 sensors.

skyy406

Exhaust work can be a huge PITA. Acura owners are pretty lucky being that its a highline car and the fact that they are new cars means that there are no rusted bolts and things of that sort. I do know however, looking at a "Engine Service Soon" light does NOT last long in my mind.