The following article appeared in OverRev mag a few months ago..
Written by Alex Keleman (k20a.org user name : 2fastxeg )
The K-Series Evolution
Naturally being a Biology major, the first thing that came to mind for the title of this story is “Evolution.” For all of us that did go to school at one point in time you’ll probably vaguely remember about the survival of the fittest- a natural process resulting the evolution of organisms best adapted to the environment. We live in a very competitive environment, to stay fast means to keep up with the latest and greatest engines that are available.
We at OverRev like to keep up with latest things that are happening and be the ones that try stuff so that you, the reader can be more educated about new technology that is being introduced in the Sport Compact market. We are doing a k20a2 engine swap which is from the Acura RSX Type S and we are putting it into a 1992 Civic hatchback. Although not many people have done this swap, we can forecast that this will be the next “hot” engine swap to get. In this story, we will go in detail of the problems that we hit and the good things that we saw doing this new swap.
We will cover every aspect as best as we can with this swap and hopefully by the end you’ll be able to use this article as a reference as you do your own k20a swap into your civic.
Ever since the B-series engine boom, there has been much research and development to produce many types of aftermarket performance parts that make good power. Right now, the B-Series has reached its plateau and with the new K-Series engine being more readily available, tuners are finally able to see what this IVTEC mechanism can do.
There has been so much technological advancements ever since the new RSX’s have been produced. Lets take a little glance at the k20 motor: it has a 86mm bore x 86mm stroke, the intake valves are 35.15mm and the exhaust side is 30.15mm with a compression ratio of 11:1 with a total displacement of 1998cc. Compared to the b-series motors, the k20 comes with a whole 1mm larger valves, the block is square, and did I mention it puts out 200hp @7,000 rpms with a whopping 142ft/lbs of torque.
You’ll also notice that the K-motors sit in the engine bay backwards compared to the B-series and the engine will spin the traditional clockwise motion. Theres a few K-series engines available, the K20a which is found in the JDM RSX –R and the K20a2 found in USDM RSX-S are the motors to get since they have the complete 3 lobe IVTEC, these are the motors that you will want for your swap. The economy K-motor would be the K20a3 which is found in the base model RSX’s and in the newer Civic SI’s have the run down 2 lobe IVTEC, which isn’t the true IVTEC that you will want, it doesn’t have a huge VTEC lobe that is found in the K20a and the K20a2’s.
When you do plan on picking up a K-motor, make sure that all engine parts and sensors are included and are not broken. One thing to look for is the Primary Oxygen Sensor in the K20’s, they are different from the B-series engine being that they are an Air/Fuel Wideband Oxygen Sensor, one way to ID them is that they are made by Denso and has 4 wires with one being blue. We personally didn’t notice this when we bought our motor and when we started up the motor, it wouldn’t run right since we were given a B-series Oxygen Sensor.
The Fuel Stuff
Lets talk a little about engine management before we get into the nitty gritty of the fuel components. We opted to go through Hondata to use their K-Pro Engine Management system; this ecu is basically your stock ecu, but after getting the Hondata treatment on it, you get a newly chipped ecu that has a USB port that you can change basically anything you want. This is a windows based program tha tis extremely easy to use, Hondata has actually loaded up many tuned maps that you can load up for your car.
You don’t even have to run to the dyno to get your new K-motor tuned if you have the basic bolt ons, Hondata has it in the program all ready. If you don’t have a budget to go the K-Pro route, Hondata offers reflash programs that take away some of the OBD2 stuff and make your car run excellent, also it takes away the key immobilizer found in the USDM ECU’s.
One of the custom things that will need to be done will definitely be the fuel system set up. With our experiences, we have decided to set up our fuel lines to circulate in cycle that would go through the fuel filter, fuel rail and then into the fuel pressure regulator which the excess fuel will go down the return line which recirculate into the gas tank.
We went over to Baker Precision in Signal Hill to help us out on our fuel set up, they know what they are doing since they are the main supplier of fittings and the sorts for Team Bergenholtz, Stephan Papadakis, Leslie Durst and JoJo Callos. All of the fuel lines can be found there and it was just one phone call away. We decided to mount the fuel pressure regulator by the driver side engine mount since this area had lots of room to stick in a wrench and adjust fuel pressure.
We also decided to go with the Golden Eagle Manufacturing fuel rail that can be picked up from www.camp1320.com, we simply chose this fuel rail because it was a quality made fuel rail that was really simple to set up and best of all it is very affordable compared to some of the other fuel rails that are offered now for this motor which was of the same quality or lower. Next thing on the list of fuel stuff is an adjustable fuel pressure regulator, this is something that is mandatory to get, there are no ways to get around this. We chose to use the Edlebrock fuel pressure regulator, the name speaks for itself, its just a quality piece that has been proven to work well and last long.
Theres two way you can go about the fuel lines, if you are on a tighter budget, you can use rubber fuel hoses with fittings or if you have a wider budget, you can go with the braided stainless steel lines, if your in baler status and can afford it, black nomex lines are another way to go. Before we go run over to go buy the fuel lines, we had to first drop in the motor and then roughly measure out where the lines go so pulled out some string to measure it out.
If you are using the Hasport mounts (which should be the only way to go) then you can just use the same measurements that we have and use the same setup. After getting the motor running and driving it around for a bit, we noticed that when we were at high end, the motor would cut off at around 100 mph and luckily since we had the Hondata K-Pro, we were able to data log our run on the free way and noticed that we started to run out of fuel at the top end. As far as the fuel system went, we had almost everything except a fuel pump, so we went to go pick up an Edelbrock in-tank fuel pump. Once we had installed that and readjusted our fuel pressure back to 51 PSI, we took the car out again and tested it and the motor ran smoothly all the way through.
Just like any other new engine swap, its going to take some time and figuring out but surprisingly this swap was very straight forward and took only one full day to do. I got to give it up to the guys over at Hasport for engineering a mount kit that was very easy to install and good instructions that are easy to interperet. The key thing to make things go smoothly is to plan ahead of all the things that you will need for this swap, I personally made a checklist of the things that I needed and with this list, everything worked our really good, just check out the sidebar for more info.
Being in California, there are many knowledgable shops that know how to do all sorts of stuff, but one shop that really sticks out in my mind for doing some of the craziest swaps is Access Motors. These guys have done just over 20 of these swaps all ready so obviously picking these guys to do our swap was the thing to do. Usually we like to do things ourselves here at OverRev magazine but this is one of those things that we are gonna need a lot more man power to finish up in one day (this is my daily driver).
Before starting we made sure that we got all the hardware that we needed for the mounts, everything is supplied all ready but just to double check we just put the mounts on the motor where it is supposed to go and checked off that we have all the nuts and bolts that we need. We aren’t going to go into pulling out the old motor since most of you guys have all ready done it or read about it, so we are going to start from where the motor is all ready out. Do the easy stuff first which is pull out the old clutch line, just go around and unbolt all the bolts and disconnect the line from the Clutch Master Cylinder behind the driver side shock tower.
Next your wire harness that goes through the firewall must be run through inside the cabin now so that the Hasport wire harness will be able to connect there. Remove the rear mount by the wall, it will be 3 bolts that are 17mm, remember to save the bolts, you are going to reused those bolts to slap on your new mount there. Next task will be to remove the stock bracket on the passenger side, it will require a spot weld drill bit, that’s the easiest way to do it. Once you get the mount off, make sure you grind down any points on the chassis where there is metal sticking out, make it as smooth as possible, once you get that done, the next task will be to mount the new bracket onto the chassis.
As you will notice, there are three holes on the side bracket, those are used as a guide for you to drill two holes, those holes previously was used to hold up your clutch line, bolt those babies up and then on top of the mount, you will see two holes that lead to your chassis. Those holes will need to be drilled through, you don’t have to drill all the way across to the other side of the chassis, but just enough to get through the sheet metal because you are going to use a long bolt to screw it down.
What’s so cool about the Hasport mount kit is that they use existing bolts holes and you’ll see what I am talking about in the pictures. With the two holes drilled, you will take the two long studs and stick it through where the existing vibration mount holes used to be at and the studs will screw right into the existing threads. We found out the easiest way to install the motor was to put the motor on a rolling cart and then dropping the whole car over the motor. Another key thing is to loosely bolt up all the brackets that go onto the engine and the bolts that go the mounts, that way you have some flexibility to move the engine around until it seats in perfectly into the chassis brackets.
There will be a total of three mounts to boltup for this kit and if you happen to tighten up one side first and not the rest, the mounts will not line up correctly. Once the motor is in, everything else is really easy. Since we took out our AC and heater core, we used the existing firewall hole to run our shifter cable through. It’s time to cut off the lip off of the existing shifter hole on the chassis once you get that out of the way, you can now go on the under the car and cut out a sheet metal plate and rivet it on to cover up the hole. We’ve learned that if you don’t cover up that hole, you can easily overdose on your exhaust gasses that gets trapped in the cabin. Hook up the shifter cables to the shifter and then lay the shifter where you feel is comfortable to you. Once you found the spot, drill 4 holes and use bolts and nuts to mount up the shifter.
When you have reached this point, give yourself a pat on the back, your only half way done. For headers, we decided to go with a DC Sports TSX header. Before we picked up the headers, we actually tried to see if there was any way we can use the stock headers, let me tell you that there is no way in hell you can get it to work without some major cutting and welding. If you are wondering why the RSX headers won’t work is that it will hit your steering rack.
The DC Sports TSX headers isn’t made specifically for this swap, but it’s a great header that will fit most of everybody’s budget and installs with no problems at all. The headers do sit kind of low, but nothing that will make them get dented up or anything. Your other alternative is to buy a custom header that is made for this swap, DTR Fabrications, Hasport, Prototype Racing, and Hytech exhaust make these custom headers for this specific swap, the only catch is they cost a bit more than the DC headers, but in return, you’ll get some more extra ponies if you get the custom ones made. Your pre-existing piping will have to receive a new flange to connect to the DC TSX headers.
Last thing to do now is to drill out the spot welds on the existing radiator brackets. In the pictures, you will see where they are located at, you will need to remove the brackets and then move them over to the left side of it. First thing you need to do is hook up the hosing to the radiator so that you get an idea of where to mount up the radiator brackets. You can use your stock radiator that you have, but if you have the budget for it, I would highly recommend a thick aftermarket race radiator.
Have a buddy hold up the radiator to where you will have it sit and then have the radiator brackets welded back on. If you don’t have a welder, you can just use a few self tapping screws, that should do the trick for now, but I highly suggest you go get it welded soon. You can use a Integra GSR lower radiator hose for the lower radiator connection. For the upper hose, you can use the stock one that you had before, but you still need one more identical hose to get to hook up if you are going to use the Hasport Billet Fan Switch/ Water Temp holder. We used the stock radiator still that we had on our single over head cam motor, the thing with this is that it will do that job of keeping the motor cool, but what we noticed was that if the car is say stuck in traffic or something like that, the water temperature definitely goes up quite a bit.
My Final Impressions
Taking this car out for its first spin with the new motor was by far the most stressful moment. All this anticipation of hearing how great this motor was and how theoritcally it would be faster than any stock motor out there finally came down to the moment where I was sitting in the car with my keys in hand. I turned the ignition on and it fired right up with a deep throaty sound, I let it warm up for about 15 minutes and took it down a empty street. I went through the first three gears and I was just in awe. There isn’t any words that can really describe how fast the motor was. I felt like a B-series engine with like 5 lbs. of boost with no turbo lag, that’s the best way I can describe it, the car just doesn’t want to stop pulling. All in all, this swap was definitely worth it. This is definitely the future for the next generation of Honda tuners, the motor is just built perfectly. I can’t wait till we can get some dyno time on this baby and tune it with the Hondata K-Pro System.
Baker Precision K-Series Fuel, Brake, and Clutch Line Kit
From Fuel Filter to Fuel Rail Inlet = -6AN Line @ 1ft.11in.
From Fuel Rail Outlet to Fuel Pressure regulator Inlet = -6AN Line @ 1ft. 8in.
From Fuel Pressure Regulator to Chassis Fuel Return Tubing = -6AN Line @ 1ft.9in.
From Clutch Master Cylinder to Clutch Slave Cylinder = 3ft.11in.
Brake Booster Line = 3ft.11in.
K20 Swap Check List
1.Complete K20 engine with ECU and ALL sensors
2. Shifter and Shifter Cables or Revotech Short Shifter
3. Custom Axles ( The Drive Shaft Shop or Hasport)
4. Engine Harness and Custom Made Cabin Harness (Hasport or Access Motors)
5. DC Sports TSX Headers
6. Idler Pulley from an EP3 Civic Si (Honda Part #’s – Pulley- 31190-PRA-000, Bracket- 31175-PRA-000, Washer- 31185-PCX-003, Bolt- 90031-PRA-000, Belt from Kragen Part # - 5070505
7. Hondata Reflash or Hondata K-Pro ECU
8. Edelbrock Fuel Pressure Regulator (P#1728) and Fuel Pump (P#17937)
9. Golden Eagle Mfg. K20 Fuel Rail
10.Baker Precision Fuel Lines, Clutch Lines, and Fittings
11.Hasport Mount Kit and Billet Sensor Housing
12.Denso Iridium Spark Plugs and Denso Wide Band 02 sensor
13.Thin Radiator Fan
14. GSR lower radiator hose