Taken from Honda-Tech.com. Enjoy. And dont be a f**king queer and start talking s**t on my post. Ill kick you in the face. Fair warning, and enjoy!
DISCLAIMER: Some of these modifications are not cheap. For all of you who have to b***h about the cost of some of these items, I have this to say. Fast, Cheap, Reliable…pick two.
I want to provide some information as to why I am backing the Single Overhead Cam (SOHC). Almost every Civic out there has or had one to begin with, and for the price of a swap you can put a turbo on there that will easily out perform a DOHC (Dual Overhead Cam) for the same price. Another thing for you weight junkies, the D series engines weight in at about 75lbs less than a B series.
Intake: First things first. Allow the engine to breath; after all, engines are nothing but big air pumps. To start off, we look at the filter and piping. Cold Air Intakes (CAI) are nice, and can be found for under 50 dollars. The great thing about the CAI is that they don’t suck in hot air from the engine bay because they are mounted in the fender well. K20’s (RSX-S for this example) have been dynometer (dyno for short) proven at +20 whp (wheel horsepower) with a CAI as apposed to the 5-8 whp with a “short ram” design. There have been dyno sheets that show a 3" piping makes great power (more air flow), the Integra Type R (ITR) CAI will fit on Civics and is unlike the EX/SI CAI, which is 2.5”.
Following the air flow we come to the throttle body. This is more of a throttle response upgrade than a horsepower upgrade. UNLESS the stock throttle body is too small to allow all the air the piston chambers can pull in at wide open throttle (WOT). Basically, adding a larger throttle body allows you to be a “full throttle” faster because of the larger volume of air. Any throttle body for a H series B series or D series are interchangeable, with one catch, you need to pay attention to where your IACV (idle air control valve) is. For example, the D16Y8 (96-00 EX) has different mounting points. On the automatic, the IACV is mounted on the throttle body and the manual has the IACV mounted on the back of the intake manifold.
The VTEC B series and B20 (CRV) throttle bodies are all 60mm in size. Except for the ITR, which is 62mm. The H22 is also a 60mm throttle body, while the Civic gets a puny 56mm. Make sure when you add the larger throttle body that you port match (make the holes the same size) the opening of the intake manifold.
Next in line is the intake manifold. You want the D16Y8, often referred to as the Type R manifold for the D series. It has short, fat runners and a large chamber to allow the air to distribute to each cylinder properly.
Also, for the NON-VTEC guys out there, you can go from this:
to this
it has the common horizontal throttle body, which will allow you to use the larger CAI's. Here is a link with a complete how-to:
http://www.makuragi.s5.com/civic_99/Y8maniswap/
NOTE: This will not work for the D17's. Honda had the bright idea to make it a return-less fuel system.
Lastly, don’t forget that heat here is a performance killer. You can invest in a Hondata intake manifold gasket. It is designed (and proven) to protect the intake manifold heat soak. I have removed and replaced my throttle body coolant lines, they don’t make enough of a difference.
Exhaust:
Lets start off with the exhaust manifold (header). There is no OEM exhaust manifold out there that doesn't need work. But, for those of you who want to stay naturally aspirated (or don't have the money for a turbo) a used aftermarket manifold for the EX is where you want to go. There are a lot of people out there who by the time they can swap have already put a header on there D series and now need to sell it. You will have to relocate your catalytic converter under the car to use this header configuration (which happens to be illegal in some states). There are two different designs for a header. The 4-2-1 (or Tri-Y) and the 4-1. It is said that the 4-1 costs you low-end torque to give you more power up top. However, if you follow this link http://www.automotiveperformanceengineering.com/header.html you will see that some 4-1's have better low and mid then the 4-2-1's. Header designs are so good that this is more a preference thing IMO. One advantage of the 4-2-1's is that you can remove the lower half when you need to pull the oil pan, instead of pulling the entire header. The HF (all Civics other than the EX and SI) exhaust manifold can be modified to add a turbo. Then you don’t need to spend the extra money on a turbo manifold. See homemadeturbo for more information.
Following the exhaust stream out, we come to the Catalytic converter. Unless yours is old, don't worry about it. For those of you who can afford to upgrade the cat, tests have shown that a 3" free flowing cat has almost flown as much air as a 3" test pipe. In fact some people were shocked at how well a free flowing cat works (and it's legal). Or go with the $10.00 test pipe from Home Depot (NOTE: Test pipes are not smog legal and you face a $3,000 fine). That's right, people have even made there own test pipes with minimal effort.
After the catalytic converter, it’s the “Cat-back”. Most people recommend using a 2.25" sized exhaust for the little 1.6L. And a lot of the aftermarket exhausts are 60mm
or 2.3 inches. I agree that they should be at least 60mm. But, you also want to make sure you get mandrel bent piping and straight through designs on both the resonator (if you have one) and the muffler. If you don't get the straight through designs, you will loose power, it's that simple. However, with straight through designs also comes noise. A good compromise has is an exhaust that comes with a silencer. You can remove them for “track days” and leave them in for daily driving.
DISCLAIMER: Some of these modifications are not cheap. For all of you who have to b***h about the cost of some of these items, I have this to say. Fast, Cheap, Reliable…pick two.
I want to provide some information as to why I am backing the Single Overhead Cam (SOHC). Almost every Civic out there has or had one to begin with, and for the price of a swap you can put a turbo on there that will easily out perform a DOHC (Dual Overhead Cam) for the same price. Another thing for you weight junkies, the D series engines weight in at about 75lbs less than a B series.
Intake: First things first. Allow the engine to breath; after all, engines are nothing but big air pumps. To start off, we look at the filter and piping. Cold Air Intakes (CAI) are nice, and can be found for under 50 dollars. The great thing about the CAI is that they don’t suck in hot air from the engine bay because they are mounted in the fender well. K20’s (RSX-S for this example) have been dynometer (dyno for short) proven at +20 whp (wheel horsepower) with a CAI as apposed to the 5-8 whp with a “short ram” design. There have been dyno sheets that show a 3" piping makes great power (more air flow), the Integra Type R (ITR) CAI will fit on Civics and is unlike the EX/SI CAI, which is 2.5”.
Following the air flow we come to the throttle body. This is more of a throttle response upgrade than a horsepower upgrade. UNLESS the stock throttle body is too small to allow all the air the piston chambers can pull in at wide open throttle (WOT). Basically, adding a larger throttle body allows you to be a “full throttle” faster because of the larger volume of air. Any throttle body for a H series B series or D series are interchangeable, with one catch, you need to pay attention to where your IACV (idle air control valve) is. For example, the D16Y8 (96-00 EX) has different mounting points. On the automatic, the IACV is mounted on the throttle body and the manual has the IACV mounted on the back of the intake manifold.
The VTEC B series and B20 (CRV) throttle bodies are all 60mm in size. Except for the ITR, which is 62mm. The H22 is also a 60mm throttle body, while the Civic gets a puny 56mm. Make sure when you add the larger throttle body that you port match (make the holes the same size) the opening of the intake manifold.
Next in line is the intake manifold. You want the D16Y8, often referred to as the Type R manifold for the D series. It has short, fat runners and a large chamber to allow the air to distribute to each cylinder properly.
Also, for the NON-VTEC guys out there, you can go from this:
to this
it has the common horizontal throttle body, which will allow you to use the larger CAI's. Here is a link with a complete how-to:
http://www.makuragi.s5.com/civic_99/Y8maniswap/
NOTE: This will not work for the D17's. Honda had the bright idea to make it a return-less fuel system.
Lastly, don’t forget that heat here is a performance killer. You can invest in a Hondata intake manifold gasket. It is designed (and proven) to protect the intake manifold heat soak. I have removed and replaced my throttle body coolant lines, they don’t make enough of a difference.
Exhaust:
Lets start off with the exhaust manifold (header). There is no OEM exhaust manifold out there that doesn't need work. But, for those of you who want to stay naturally aspirated (or don't have the money for a turbo) a used aftermarket manifold for the EX is where you want to go. There are a lot of people out there who by the time they can swap have already put a header on there D series and now need to sell it. You will have to relocate your catalytic converter under the car to use this header configuration (which happens to be illegal in some states). There are two different designs for a header. The 4-2-1 (or Tri-Y) and the 4-1. It is said that the 4-1 costs you low-end torque to give you more power up top. However, if you follow this link http://www.automotiveperformanceengineering.com/header.html you will see that some 4-1's have better low and mid then the 4-2-1's. Header designs are so good that this is more a preference thing IMO. One advantage of the 4-2-1's is that you can remove the lower half when you need to pull the oil pan, instead of pulling the entire header. The HF (all Civics other than the EX and SI) exhaust manifold can be modified to add a turbo. Then you don’t need to spend the extra money on a turbo manifold. See homemadeturbo for more information.
Following the exhaust stream out, we come to the Catalytic converter. Unless yours is old, don't worry about it. For those of you who can afford to upgrade the cat, tests have shown that a 3" free flowing cat has almost flown as much air as a 3" test pipe. In fact some people were shocked at how well a free flowing cat works (and it's legal). Or go with the $10.00 test pipe from Home Depot (NOTE: Test pipes are not smog legal and you face a $3,000 fine). That's right, people have even made there own test pipes with minimal effort.
After the catalytic converter, it’s the “Cat-back”. Most people recommend using a 2.25" sized exhaust for the little 1.6L. And a lot of the aftermarket exhausts are 60mm
or 2.3 inches. I agree that they should be at least 60mm. But, you also want to make sure you get mandrel bent piping and straight through designs on both the resonator (if you have one) and the muffler. If you don't get the straight through designs, you will loose power, it's that simple. However, with straight through designs also comes noise. A good compromise has is an exhaust that comes with a silencer. You can remove them for “track days” and leave them in for daily driving.
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If your looking for a 4-1 and don't mind looking extremely different look at the bisimoto header. Bisimoto if you haven't heard of him built the fastest SOHC civic. The header (looking something coming out of "aliens" ) uses equal length primaries to increase H/P. Very cool tech.
Then again I hadn't messed around with the transmission before I crashed, so I was bouncing off of the rev limiter. Fun stuff when you're running 4-1's, a CAI, and a test pipe -- nice and loud and it sure as hell doesn't sound like a bumble bee zooming around.
awesome write up man. I'm deffintily gonna print that out for later use.