Build Pics CBR 600RR Motorcycle Throttle Bodies in 69 Ghia

[BaconatorX]

I finished building most of my fuel injection system at the end of summer. I did the electronic ignition system earlier in the spring time. I did a lot of custom fab work and tried to do the fuel system as cheap as possible. I'm a 21 year old student studying mechanical engineering. I started college with a beetle and learned a lot from that car.

I don't have a cost total but I know the fuel line cost more than anything else in this build. For electronic ignition I spent somewhere near $400-500 for the Microsquirt, 4 Ignition coils, trigger wheel and sensors. I spent $40(so cheap) on the used throttle bodies, around $100 on air filters, and around $200 or so on fuel line components, probably $150 or so on the pump and regulator. All in all I am very pleased with the purchase prices and outcome of y project.

I'm just now getting around to posting the pics and build steps and all that. I hope you guys enjoy this!

Here's the car, my 1969 Karmann Ghia. I'll list the engine specs here since you might be curious. It's a scat 1915 longblock. used to have kadrons and a bosch 034 which ran the car decent, but I got tired of adjusting and changing out ignition parts and I like to do my own thing so fuel injection and electronic ignition was the next logical step. It's got an 1 1/2 ceramic merged exhaust to a 3 inch Stainless muffler of unknown make(came with the 1600cc when I bought the car) The heads are pretty mild, built of 043 casting, can't remember the valve sizes off hand. Scat c35 cam, 1.1 rockers on a HD shaft.






In the springtime of 2014 I did a hidden trigger wheel and 4 LS2 coils, using Mario's setup. The brain is a Microsquirt with MSextra code.


I figured out that coils would all fit behind the fan shroud and stay nice and hidden.




Pics of them on the doghouse cooler. And yes they fit in the engine bay, on a Karmann Ghia at least. I have the thin black tar-like sound barrier stuff so that's pretty thin compared to the particle board stuff. They barely rub the thin black firewall material stuff so it might not fit in other cars.


Here's the hidden trigger wheel and hidden coils in the car. The distributor is still in the car. It still spins. It throws the older vw guys through a loop when they ask me about it. I've had people ask me if i'm afraid the car will get stolen. They ask if that's why I took the cap off. They get even more confused when I tell them to watch me start it up. LOL.

I'm open to any ides for welding or attaching anything to the top of that distributor for a laugh. I couldn't get the damned drive gear out so I don't think I'll be taking the distributor out soon.


I ran electronic ignition for a few months and really loved not having to deal with a distributor. But I started seeing threads showing motorcycle ITB builds on the cheap and decided to start looking into doing that on my own.

So I found these on Craigslist. The guy had a motorcycle accident many years ago and was slowly parting it out. 2004 CBR 600rr Throttle Bodies.



I picked these up for $40 used with the injectors.


It took a lot of researching but I found a site listing these fuel injectors as 200cc/min which is really close to exactly what I'd need. I tested them with rubber tubing and compressed air and a battery charger to make sure they were all clean inside and still sprayed fuel. They worked well.

The throttle bodies split open really easily without any cutting or difficulty I began the process of getting the parts together to build the intake manifold.


For the intake manifold I used hand tapered tubing. I remember I got the idea from a Hot Rod Magazine page that came up when I was researching how to do it on your own. So maybe their guide is more thorough and clear compared to my few pics. http://www.hotrod.com/how-to/paint-body ... red-cones/

This piece of fence tubing was a perfect fit. there is a bit of a burr there from being freshly cut but I cleaned everything up. I really could not have asked for a better fitting piece of tubing, it's almost perfectly flush with the rubber seat. the Throttle valve on the CBR 600RR is advertised as 38mm with no venturii restriction inside(which i've read will flow similar to a 45-48mm carb), I cannot remember the inner diameter of the tubing but I could measure it for the curious when I am home at some point.


Since I'm on stock port sizes I needed to taper the tubing down to the stock intake size, 33 or 34 mm, I can't remember which. I worked out the math for tapered tubing on paper. It was basic circumference subtraction take the circumference from the existing tube and subtract the smaller 33mm radius's circumference. Pictured below is the length that need to be taken away from the tube circumference in order to make a diameter circle. You do this by cutting out a pie shape. Take an equilength/marked piece of string and scribe into the pipe. Place tape on the tubing with the string end points on the top of this pic, and have them meet at an equidistant mark down the tubing.





And then cut the thing. It took a couple attempts to get the exact science down so me and my dad were making the exact same cuts and same size tubes each time.

I didn't take many pics of this process unfortunately cause I was busy working away. Oh you want to make sure you leave extra length on both sides so you can leave room for error and imperfect or warped welds. Plus you'll want to flat both ends to be parallel to each other, it's nice to have extra headroom to work with. In other words make the taper smaller than it needs to be. Once the pie shape has been cut out of the tube then you're gonna wanna hammer the tube back into itself to form a tapered tube. you start at the closest point and work slowly to the larger cut. It's nice if you have a good anvil to work with.


Close to ready to weld. Don't forget to grind the enamel off your enameled galvanized tubing. also it's good to grind in a 45 degree chamfer on each edge of the edges of the pie shape so the weld has a nice place to fill in. sorry no pic of the chamfer here. I don't think this was a finalized tube in this picture. I think this was an early prototype, I did not do that bad of a job with my hammer on my finalized tubes.


unfortunately I don't have a lot of the pictures of my math and drawings. But here's the general dimensions we were working with. the throttle hole spacing above and the port spacing below. I don't think this picture was a finalized tube, i think this pic was an early test tube. the final tubes fit perfect. like I said above it takes some math, and a bit of an oval shape on both ends of the tube to make the angles work.


Here's a pair of manifolds after welding, and shaving the tops and bottoms to flat and parallel and correct spacing. They're about as darn close to perfect as you can make in a woodshop.


I worked at a machine shop over summer so my boss let me have some scrap aluminum that was laying around. Up to this point in the fuel injection project I have spent only $40 on the throttle body portion of the project. I ended up paying the shop welder when he did the welding on his own time. I don't remember what I paid him so don't forget to factor in welding costs on your project. The goal was to do everything on the cheap, hence making the manifolds and everything else.

Here's the slosh pot I made from scrap aluminum. again with the 45 degree chamfer so it welds nice. top plate and bottom plate i cut on the band saw(ever see a better looking circle cut on a band saw?). I think the tube was like a 3 inch tube, thin walled.


All welded up. I love the shop welder.


I made these fuel rails out of scrap aluminum at the shop. Did this on the manual mill.


I got the dimensions for the rail from the existing rail that came with the throttle bodies.


Initial fitment, nice and snug, and to the same sizing on the Honda fuel rail.

[BaconatorX]

Part 2:


Oh I also tapped it for 3/8 pipe thread to match the AN fuel fittings I was going to be using.


Next was the challenging task of making intake air filter adapters since the original throttle bodies air filter was attached to a box that surrounded the 2 throttle bodies. I found 1 and 3/4 inch?(I think that was the size maybe was 1.5 inch) exhaust tubing to be a close enough fit. the local muffler guy down the street gave me this tube for free. I had to turn down the outer edge that went into the throttle body, there was a very discrete taper over a few thousandths so I had to lathe it down at an angle to get it to have a very tight press fit. then I cut out the insides to match the top of the throttle body.


pretty darn good fit. oh yeah but the tool i used on the lathe wasn't long enough to reach my depth so theres a tiny bit of mismatch from turning the part around in the lathe. I'm okay with a little imperfection like that.


You can see the tapered bottoms here. I think it was like a 2.5 degree taper or some nonsense like that.


All nice and shiny


I made a slotted fuel rail bracket and taped some hex bolts into the side of the rail. The slots on the fuel rail side allowed me to give the rubber seals a very tight fit by giving it pressure and then tightening them into place.


They work! I pressure tested them with a pressure regulator and shop air and They didn't leak at all. They don't leak fuel either.


Press fit air filter adapters isn't good enough so time to grind a bit out of the top of the throttle body and get ready to weld in a bracket thing.


Welded and bolted into existing bolt holes on the throttle body.


Flat steel scrap getting ready for being the bottom plate.


Manifold bottom plate shaved down to fit and tacked into place. also manifolds had been de-enameled. Also pictured is the bracket I used to make sure the top of the throttle body does not pop off the manifold. two long bolts and a flat piece of steel over the top. not the prettiest but it does it's job really well.


Dad helped with thinking out the simple throttle body bracket setup, more pics later.


Awesome welder friend


Starting to look proper.


I apologize for not having any intermediate pics of the throttle body bracket or the linkage I made. but here is the rough setup in the car. with the slosh pot in the top right. I set the slosh pot up with aluminum weld ins. This is to handle any sloshing that may occur due to the completely far fetched idea of cornering hard or accelerating hard. It has an excess fuel return line to the gas tank at the top to handle any excess fuel pressure, a fuel input line from a small electric feeder pump, a excess fuel pressure return line from the pressure regulator. The big fuel pump is fed with a big 1 7/8 fuel feed tube at the bottom of the slosh pot to the big walbro gss340 fuel pump. This is an in gas tank fuel pump but it wasn't hard to adapt it to the back of the car. The thing is pretty loud when not in a gas tank though. the fuel pump is secured to a bracket made out of aluminum angle stock bolted to the bottom of the engine bay. The fuel goes from the pump through rubber fuel injection line through a fine micron fuel filter, from there it goes into the Mallory adjustable fuel pressure regulator. There's a closer up picture just below.



I used one of the existing pulleys that came on the throttle body. I used bicycle brake/shift cable and half of a scat universal linkage to build my throttle cable linkage. I had to build a bracket to fit the left side throttle body to replace the pulley since the exiting pulley would not work with any setup I could think of. the pulley on the right has it's existing adjustable stops, the left bracket is adjusted by the scat bar linkage. I keep both in equal adjustment by adjusting the scat bar linkage and cable tension. I use one of those snail air flow meters to make sure they idle right. It's not perfect and I know it could be a lot better but I was running out of time as the summer was coming to a close so I had to work with what time I had. for the moment it works well enough. in the future I'll probably make something better.


I matched the radius's of the original kadron valve and also matched the radius of the pulley on the right to the cable attachment point for the left side. It isn't perfect but it opens both at a very nearly 1:1 ratio.


I painted the intake adapters blue with some rustoleum anti rusting stuff after bead blasting them. K & N has some nice small air filters in their custom air filter section, I can't remember which model of filter I bought.


Next up in the pictures is the fuel return line. there's a nice slotted/grooved track that runs from the back of the pan to the front. I used EZ bend fuel line pushed through some spare air hose as an insulator/protector. It's not exposed to the ground at any point, it's set into the body. There are other raised portions of the car body that would scrape first. it's not exactly through the tunnel as I'd like but it works just as well. Maybe some day i'll have the time and resources to do this proper but this is what I had at the time.

Put a hole through two portions of the body, didn't enter the cabin.





I don't have a picture of the upper section but we added a T into the fuel blow off valve thing for the fuel return line inside the trunk.




Also not yet pictured is my o2 sensor in my exhaust, those pics will come soonish. I will probably be finishing my CLT sensor soon as well.