K20 project off to a good start, volume 2

Discussion in 'Workshop Forum' started by Rodger, Jul 11, 2017.

  1. Rodger

    Rodger True Classic

    Olympia, WA
    Well, I was pretty bummed when the Photobucket debacle happened as my entire K20 build thread is now pretty useless with no photos. It would take me forever to reload them all, but that is a project for another life. Anyway, I figured I would continue with my progress in a new thread.

    Once I got the AC lines completed, I decided I needed to the get the shift linkage in place first, before working on the plumbing. There is so much going on with the plumbing and electrical connections to the engine in such a tight space that I find I have think about it, play with different ideas and then build it layer by layer. The shift linkage is the first layer.

    I had modified the Honda shift cable connection points on the transmission to accept the 10-32 Heim joints that come on the shift cables with the MWB K20 swap kit. There are also extensions that needed to be added to the shift cable bracket on the transmission. These were welded on before I had them powdercoated. Shift linkage 07.JPG

    I then attached the other ends to the shifter mechanism that comes with the kit. It took a little bit of playing with the adjustment nuts to get the right length, but not a lot of time. Matt had this dialed in pretty nicely.
    Shift linkage 03.JPG

    I did find that the end of the passenger side tab was hitting where I had the AC line routed, so I moved it to the center of the tunnel and attached it to the throttle cable tube. This kept it as low as possible so it didn't interfere with the shifter motions.
    AC hose re-routed.JPG

    Here is what is going on in the tunnel under the parking brake handle.
    Shift linkage 06.JPG

    Here is the shifter bolted into position. All of the gears engage smoothly and with very short throws. Can't wait to drive it someday.
    Shift linkage 05.JPG
    darwoodious likes this.
  2. kmead

    kmead Over half way.

    "Can't wait to drive it someday"

    That may well be the understatement of the year.

    Great progress. Can't wait to see more updates.

    Sorry about the PB issue it is distressing for us all.
  3. Rodger

    Rodger True Classic

    Olympia, WA
    With the shift linkage in place, the next layer I worked on was the fuel system. First was figuring out the best location for the fuel pump. Here is the stock location of the fuel pump on a fuel injected X1/9. I’d forgotten how filthy this car was when I was taking it apart.

    Here’s a picture of the mounting holes after the car was painted.
    Fuel pump mounting.jpg

    Anyway, there are two M6 threaded holes for attaching the mounting bracket for the fuel pump in this location that are not there on the earlier carb’ed cars, but I thought that would be the best place to try.

    Unfortunately, the stock bracket holds the pump out too far from the bulkhead and it interferes with the Honda transmission. So, I just got a piece of steel plate, drilled a couple of holes to match up with the holes on the car, and tapped a couple of other holes to line up with the brackets that hold the pump and threaded in some new rubber mounts so that I could still use the parts of the bracket that hold the pump body.
    Fuel system 01.JPG

    I cut off the excess threaded rod that protruded through the plate as the plate will be mounted flush to the car. Bolted the plate in place, then attached the pump with the brackets and the rubber cushion strip to the mounts, then connected the fuel lines to the tank. I used a low pressure fuel filter from MWB to catch any large debris before it gets to the pump since my gas tank had been acid cleaned and sealed, so the internal filter was no longer there.
    Fuel system 03.JPG
    Fuel system 04.JPG
    Fuel system 05.JPG

    I mounted the adjustable fuel pressure regulator that I got from Hybrid Racing to the inner fender just below where the ground post is. I went with this one as you can set it up to have a single feed line to a center port on the fuel rail. The return line to the gas tank comes off the bottom of the FPR. I also got their fuel filter and everything is connected with -6 AN connectors.
    Fuel system 06.JPG
    Fuel system 07.JPG
    Fuel system 08.JPG
    As I was laying out the lines, I had to keep making sure that nothing would interfere with the movement of the large counterweight that is on the shift lever. It pivots from left to right quite a bit as well as goes up and down.
  4. Rodger

    Rodger True Classic

    Olympia, WA
    The fuel pressure gauge can be attached to either the FPR or the fuel rail. I decided on the fuel rail, since if I mounted it on the FPR, it will eventually be hidden by the air filter once I get the throttle body mounted. When I was looking at fuel rails on the internet, I found a lot of photos of “tucked” motors that used the center feed line. That’s where I also got the idea to run the wires to the fuel injectors from below as I think it looks a lot cleaner.
    Fuel system 11.JPG

    I had a few extra feet of the braided hose so I used it to dress up the evaporative emission lines from the gas tank.
    Fuel system 10.JPG

    Here’s how it all looks from above.
    Fuel system 12.JPG

    The next installment will be on the cooling system plumbing.
  5. Ulix

    Ulix True Classic

    Stuttgart, Germany
    Hey Rodger,
    you are succeeding in something that I find quite hard.
    You are making major technical changes to your car, reengineering major components AND applying extreme attention to detail, paying attention to every little nut and bolt.
    I can usually only forcus on one of these two.

    Keep the pics coming!
    motoTrooper and kmead like this.
  6. Rodger

    Rodger True Classic

    Olympia, WA
    Thanks for the encouragement. Not sure I am really re-engineering things, just trying to marry a combination of things to come up with a solution that will hopefully work well together. I am a bit fussy about how it looks and I am really trying to avoid having it look like a patchwork of stuff just thrown together. Of course, I would have never attempted something like this with out the excellent swap kit from MWB and all of the ideas that I have gathered from the great contributors on this forum that take the time to share their knowledge with the group.
  7. kmead

    kmead Over half way.

    Out of curiosity, what braided hose are you using? The stuff you have has a shiny look to it which suggests it will hold dirt less. Or are my eyes deceiving me?

    Really nice work as always. I am with Ulix, you are doing a great job of knitting together a clean and considered set of solutions that unifies into a car that looks like the factory put it together. Bravo!
  8. Rodger

    Rodger True Classic

    Olympia, WA
    I used Russell ProClassic II -6 AN hose from Summit Racing. https://www.summitracing.com/parts/rus-632075. There are several brands available that look similar. It is a black nylon braided hose with internal braided stainless bonded into the liner. They say it can be used for fuel, oil, or antifreeze. The nylon does have a shiny, clean appearance that I really like. You can definitely see the difference if you compare it to the standard braided hose shown on the picture I posted of the underside connections to the fuel tank. I already had some of that larger standard braided hose on hand that I had bought from MWB a few years ago when I did my carb to FI conversion on my '79, so I just used that for the supply line from the tank to the fuel filter to the fuel pump, as it is not a pressurized line.

    When I bought the fuel rail from Hybrid Racing, I had also bought their tucked fuel line kit, that came with three pre-made -6 AN black braided hoses. Of course, it was intended for a swap into a Civic, or something like that, so the lengths weren't quite right for what I needed. The Russell hose looked to be a match for what they used, so I bought another 10 feet from Summit Racing along with a couple of fittings that I needed. I took apart the hoses I got from Hybrid Racing and used the fittings to make my own custom hose set. I used the pieces from the Hybrid set to make a lot of the evaporative system hoses. If you look at the above photo of the fuel pressure regulator before I connected the fuel lines to it, you can see the original rubber hoses that I had used to make the evaporative system. Once I had the fuel lines in and how nice they looked, I had to change the evaporative lines to match. Fortunately, I had just enough hose to make it. Total, I probably used about 16 feet of hose, with the 10 feet I bought and what came in the Hybrid kit.
    kmead likes this.
  9. kmead

    kmead Over half way.

    Thank you. It was the contrast of the older fabric covered hose under the car versus your evaporative hoses that caused me to ask. Really nice material that looks great and should perform well beyond exactly what is needed.

    Thank you for taking the time.
  10. Rodger

    Rodger True Classic

    Olympia, WA
    Cooling system, Part 1.

    The cooling system plumbing routing for the K20 swap is probably one of the more variable aspects of this build, probably because the swap kit from MWB does not come with any parts related to the cooling system. So, it is pretty much up to the individual building it as to how they do it. I have looked at pictures of different swaps to see how each one was done and I had a chance to study in person, Roobus’s swap that was done by MWB. There is a lot of plumbing that all comes together in a very small space under the intake manifold, since the water pump intake and the underbody cooling tubes and heater supply tube are all next to each other right below it. I will do my best to describe my thinking about the parts I used for mine. I apologize if it rambles a bit, but I figured that at least it will give others out there some insights into at least one way to do it.

    All of the swaps that I have seen delete the stock thermostat housing as it takes up a lot of space and doesn’t really point in the right direction to meet up with the under-body cooling tubes very well.
    IMG_0969.JPG The MWB swaps I’ve seen use a custom made plate with an inlet to replace the thermostat housing on the water pump. They used an external thermostat from a Lancia that allows for recirculation of the coolant until the engine warms up. It seems like there are a few different styles of external thermostats which influences the way the plumbing would go depending on the direction of the connections. MWB also did some extensive welding fabrication to modify the stock upper coolant housing from the cylinder head to redirect the flow to go under the intake manifold to the external thermostat and then to the cooling tubes. These pictures are from Roobus's swap.
    photos for Pete 065.jpg

    K-Tuned is an outfit that built their business around K20A2 swaps (mostly into other Hondas) and makes quite an assortment of very nice machined parts. They make an upper coolant housing with many different configuration options. They also have a swivel neck thermostat housing to replace the stock one which gets it much closer to the water pump as well as allowing for an infinite variety of directions for the inlet. This housing also has an inlet for the recirculation circuit that gets deleted with removal of the stock thermostat housing. I decided to try and use the K-Tuned parts instead of trying to have someone weld up something custom for me. Since I was using an external thermostat, I just left the thermostat out of the housing since it is only a single action thermostat as opposed to the double action of the external Lancia one.

    As I was designing my approach, there are several circuits that have to be considered. There is the recirculation circuit from the cylinder head to the thermostat and then to the water pump until the engine warms up enough for the thermostat to open and allow the coolant from the radiator to flow to the water pump. There is the main flow from the cylinder head to the radiator than back to the thermostat and on to the water pump. There is the heater supply from the cylinder head to the heater core, then back to the water pump. There is the supply and return from the coolant reservoir tank. There was good discussion about this in this thread. https://xwebforums.com/forum/index.php?threads/just-started-my-k20-project.26527/ I used the same basic cooling system routing as on Roobus’s X as diagramed by Pete Whitstone, which is pretty much how the stock X1/9 cooling system works. Here is my version of Pete’s diagram.
    One thing that is unique to my build is the aftermarket air conditioning system that has a mixing valve to control the temperature of the heater core. Unlike the stock system that has a simple valve that just increases or decreases the flow to the core, the valve for the Hurricane system that I used has four connections to it, two from the engine and two to the heater core, so I assume that there is coolant flowing through the valve continuously.
    As you move the temperature rheostat slide towards hot, it diverts it to the heater core so there is probably an instant response since you don’t have to wait for the hot coolant to come all the way from the engine as with the stock set-up.
    Anyway, the way it worked out to fit the valve in the tight space behind the evaporator unit, the flow through the body pipes ended up being backwards from stock. The pipe that runs through the shifter tunnel needs to be connected to the water pump inlet, whereas the stock set-up has that pipe carrying the hot water from the cylinder head. My connection from the cylinder head goes to the underbody pipe that comes up through the floor pan into the tunnel under the heater core. Also, the hose that normally runs from cylinder head through the firewall, then through the spare tire well and then into the tunnel is deleted since I have the access box and subwoofer in the spare tire well. I just ran the hose from the pipe in the shift tunnel straight out the hole in the cover plate that has the parking brake pulleys, along with the shift cables. This hole was used for the shift rod to the transmission in the stock application.

    The stock K20A2 recirculation circuit comes off the cylinder head outlet on the intake side of the engine. This same housing is also the large outlet to the radiator. The recirculation circuit is the angled hose heading under the intake manifold then to the thermostat housing.

    The outlet for the heater core comes off the cylinder head on the exhaust side of the engine. This circuit then goes through the firewall to the heater core, then back out to connect to a ¾” pipe which runs along the back of the engine then bends around to go under the intake manifold and connects to the thermostat housing. There are a couple of small water take offs on this pipe that feed some of the temperature related items that are not needed for the swap. Although the main/recirculation outlet and the heater outlet are on opposite sides of the cylinder head, they are both connected to the large common cooling space in that end of the cylinder head.

    I decided to use the heater outlet pipe for the recirculation circuit since it is closer in size to the 1" inlet of the thermostat. I connected a 180-degree bend hose to go from the outlet right back to the ¾” pipe.
    I cut off part of the heater outlet pipe to make the bend shorter. I cut off the small take off under the cam position sensors and closed it with a piece of hose clamped over the hole. Not very elegant, I will admit. I cut the pipe before it made the final bend to the thermostat so that it ends under the intake manifold. I didn't get any good pictures of just the pipe before more things got laid on top of it.
    Continued in the next post as Xweb will only allow 10 photos per post.
    lookforjoe and darwoodious like this.
  11. Rodger

    Rodger True Classic

    Olympia, WA
    Cooling system, Part 2.
    Here is a photo of the recirculation pipe heading under the intake manifold.
    Here is a picture of the pipe where it ends under the intake manifold as well as the K-Tuned swivel neck thermostat housing in place.

    My original plan was to use the other small take off to go to the top of the expansion tank and but that was before I had the engine in the car and saw the height of the expansion tank compared to the main outlet and realized that there was a potential to trap a lot of air in the cylinder head when filling the coolant. I thought I would use a K-Tuned filler neck option on their coolant housing, but it took up a lot of room that I would need to run the intake tube from the throttle body to the intake manifold. So, I capped off that small take off tube and ran the upper hose to the expansion tank from the small port that was already tapped on the top of the K-Tuned outlet. This shows that port as well as how I added the Fiat temperature sensor for the temperature gauge.
    I debated tapping a hole into the cylinder head, but that idea scared me too much in case I screwed it up, so I elected to put in in the upper coolant housing. It may not read the temperature exactly right until the coolant starts to flow to the radiator.

    There are a lot of tight bends in the coolant circuit so once I figured out the basic shape and path, I would bend a coat hanger to approximate what I needed, then went down to my local O’Reilly’s auto parts store to look at what they had hanging on their wall. The folks at O’Reilly’s were always fine with me buying some hoses that looked right and they never complained when I brought back the ones I didn’t use. They were just as accommodating when I was trying to figure out the correct length for my serpentine belt. I found a couple of pre-formed hoses with right angles that I connected to make the upper expansion tank circuit.

    The expansion tank that MWB recommends is a VW style. I mounted mine in the stock location but with a custom bracket that was welded to the left shock tower when all the other engine bay mods were being done at the body shop. I connected the bottom 5/8” outlet with a length of heater hose run along side what is now my recirculation pipe and the fuel supply line under the intake manifold to what K-Tuned calls the recirculation fitting on their swivel thermostat housing. So that finishes off the expansion tank circuit.

    For the large coolant runs, I used various shapes and sizes of black silicone hose from Pegasus Racing. They have an amazing assortment of all types of bends and sizes as well as nice aluminum hose connectors. To connect the thermostat, I got a 45-degree bend tubing with 1-3/8” legs. That is the size of the underbody cooling tubes and the large connections on the thermostat. One leg is connected to the left side cooling tube and the other leg to the large thermostat intake. The large outlet from the thermostat was connected with a 45-degree bend tube with one 1-3/8” leg and one 1-1/4” leg. 1-1/4” is the size of the K-Tuned coolant connections.

    To finish off the recirculation circuit, I got a 90-degree bend silicone hose that is ¾” on one leg (for the pipe that ends under the intake manifold) and 1” on the other leg as 1”is the size of the small inlet on the thermostat. This photo shows that elbow connected.

    This shows the lower hose from the expansion tank connected to the swivel housing.

    The large coolant run from the upper coolant housing is connected to the right side underbody coolant pipe by a 180-degree 1-1/4” hose that was shown in one of the above photos, connected to a straight section, connected to a 90-degree hose, connected to a 45-degree hose that is 1-1/4” on one leg and 1-3/8” on the leg connecting to the underbody pipe. Definitely a lot of trial fitting to get the lengths of each section cut to appropriate size.

    I connected the elbow from the recirculation circuit to the thermostat with a second 90-degree hose that is 1” on both legs.
  12. Rodger

    Rodger True Classic

    Olympia, WA
    Cooling system, Part 3.

    Last was the heater core circuit. To make the connection to the water pump, I needed a hose to connect to the pipe in the tunnel, exit out the parking brake pulley cover, then make a 90-degree bend to avoid the engine subframe and head toward the water pump. I went looking at my local O’Reilly’s for various pre-formed heater hoses. For the hose from the pipe in the tunnel, I used Gates #18077 which is a long straight section with a 90-degree bend at one end.

    To connect to the water pump, I needed another inlet on the K-Tuned swivel thermostat housing. There is another tapped hole, but it is for the Honda radiator fan thermoswitch and the threads are not the same as the recirculation fitting. Plus, it is pointing in the wrong direction anyway. This is how the swivel neck comes from K-Tuned.
    I will plug that hole with the supplied plug from K-Tuned, but then I drilled and tapped another inlet pointing straight forward and added another K-Tuned fitting.

    Another trip to O’Reilly’s yielded Gates #18821 to connect that fitting down past the framerail and Gates #19056 to make two 90-degree bends that are at 90-degrees to each other to connect to the tube coming out of the tunnel. Here is what it all looks like. Just need to get a few more hose clamps to finish it off.

    The final connection is for the supply to the heater core. The K-Tuned upper coolant housing has a tapped opening intended for replacing the stock recirculation connections, but I used that with a straight fitting to connect a length of heater hose that goes down past the fuel pump, between the engine and the subframe then over to the underbody heater pipe.

    I had to cut this pipe off a bit as it angles away from the direction I was coming from, plus it is too close to the engine mount on the subframe to even connect to it.
    The only thing left is to add the hose clamps as I ran out of the size for the heater hoses.

    Well, if that was exhausting reading about it, it was even more exhausting working on it and then writing this up. Hope someone enjoys it. Have to put the K20 swap on hold for now as my ’79 needs some TLC for a bit.
    kmead, lookforjoe and darwoodious like this.
  13. Rodger

    Rodger True Classic

    Olympia, WA
    Here's one final picture of the engine bay with the cooling system in place.
    Yves, kmead, motoTrooper and 3 others like this.
  14. lookforjoe

    lookforjoe True Classic

    Really nice work - very cleanly laid out! I can appreciate the time & effort that went into making this all come together. I would have have to make multiple drawings of all the hose routings to figure that one out - no way I could do it in my head.

    The only thing I'm not clear on is the part where you said you cut a pipe & capped it with a piece of hose?? That sounds a touch dodgy, but perhaps I misunderstood?
  15. motoTrooper

    motoTrooper True Classic

    Another great piece of documentation with high standard work. I wonder about the capped hose also...
  16. Rodger

    Rodger True Classic

    Olympia, WA
    Yes, I agree that the cut pipe with the hose "patch" is my least favorite part. I found a couple of other pics of the pipe as I was taking the engine apart. The small branch pipe that I cut off is circled.
    I cut it off flush, then took a piece of 3/4" heater hose, wrapped around that opening, then put two hose clamps around it side by side to seal it. I should have had it welded off, but the pipe is not that thick, so didn't know if that would work.

    Here's a better pic of the pipe and the stock recirculation circuit. The circled area is the other take-off that I was going to use to go the expansion tank, but ended up just capping it off. The line is where I cut the pipe.

    After I finished my post, I got to thinking about the whole 180 degree hose and the pipe. I have another idea that will get rid of the pipe so it is still a work in progress. Thanks for the feedback.
    Yves likes this.
  17. Pete Whitstone

    Pete Whitstone True Classic

    McKinney, TX
    Great work Rodger. I am amazed at how much the pics from Roobus's car look like mine. As delivered from MWB, my car had a single action thermostat in the K-tuned housing. Cooling was not optimal below ~3k rpm. As in, constant overheating. So I designed my own system, with input from Roobus and Jonathan Pack, which also incorporates the Lancia dual action stat. No problems since.

  18. lookforjoe

    lookforjoe True Classic

    At a minimum, you could silver solder or braise a cap over the removed branch. I don't think the sleeved hose is a solution that will hold up over time.
    kmead likes this.
  19. kmead

    kmead Over half way.

    Indeed, a cap might have been a better solution says the man looking in the rear view mirror.

    Amazing work putting that puzzle together in such constrained spaces.
  20. Rodger

    Rodger True Classic

    Olympia, WA
    Thanks for pushing me to make it better. I pulled the pipe and took it over to Resurrection Auto Body, the shop that did the original body work. I asked if they could weld the two take offs closed. Shawn said that he has a guy that does nice TIG welding and he will do it tomorrow.
    lookforjoe and kmead like this.

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