Wednesday, July 23, 2008
Injectors and electrical connectors
The fuel injector harnesses were built using fuel injector pigtails, and in parallel, and will use the 2 banks that Megasquirt can controll and alternate them. I also tested all the connectors as I do not want any surprises when I try to start it. I have also started the connectors for the clt, the iat, and the negative post of the coil. I will also wire the O2 sensor cable, and wrap it up for future installation after I have installed the shorty mustang headers (future project).
Tomorrow I expect to finish the basic cabling, and will start wrapping it up so that it looks nice and neat. The fuel Injectors are in the car, and I am waiting on the 14mm drill bits to make the final cuts in the fuel rails. Once that is done, I can assemble all the fuel injector components, including the FPR, and tie down the fuel injector harness and the sensor cables so that they are not all over the engine compartment.
Saturday, July 19, 2008
Bad Wedding, Fuel Rail and Air slide valve hole cover
This weekend though was taken up going to a wedding, but I will start with the new cabling on Sunday. It should not take too long, as I have all the parts of where the cables go scoped out, and just need to run the cable, install the relay board in a place that will not get too wet under the hood, and then start the long process of figuring out what goes where. I am also going to run new power cables to the front lights so that I can relay them, and avoid overloading the 30 year old cabling, and switches.
My main concern right now is getting the exact length in between injectors so that they seal perfectly, and do not have fuel leaks, as that generally is a bad thing. I have also backordered 2 m14X1.5 female to AN6 male adaptors that will replace the lines coming in from the fuel pump right behind the booster, so no need to cut the original hoses and clamp them. It think that it is a far neater, and safer solution overall, and safety needs to be first.
The fuel system itself is designed with 300PSI hoses, connectors, and gaskets, even though the fuel pump will only get to 125 max, and is used to running at 75 for the CIS system.
As what creates the pressure on the system is the fuel pressure regulator, and the mustang 19LB injectors run at 37PSI, the fuel pressure regulator will be set at 37 PSI. When designing an FI system, always remember to put the fuel pressure regulator after all the injectors, in the return line, as this way, you will get the correct pressure before it. The way you get pressure in a hydraulic system is through blockage, and that is what a FPR does... It blocks the flow of gasoline UP to the pressure you set it. You really do not care about the pressure after the FPR, and putting multiple FPR's is just a recipe for a very hard to tune car as you have built up the pressure before the injectors. Some racing applications, and nitrous might use 2 or even 3 pressure regulators depending on the different needs, but that is way past what I intend to do with this car... I just want a nice car for a pleasant sunday drive, and if I get passed by a vespa, so be it.
Tuesday, July 15, 2008
Fuel rails, and old Air Slide Valve cover
I bought a piece of 6060 aluminum stock, approx 1/2" thick, 3" long, and 1.5" wide, and proceeded to cut it to shape. I could have just left the square piece, but wanted it to resemble something that was not just drilled, so out comes the hacksaw.... If you have ever worked with 6060, this was a long tedious process. It is hard for aluminum, and after about 2 hours, I had a rough diamond shape piece.
I then proceeded to round up the edges, drill the proper holes, and recess them a bit, and now it should make an adequate cover for the hole. For the next car, I will do the same, and use this piece to put in the CLT, as no other mods need to be made on the Intake manifold (I previously had a 3/8NPT thread tapped out in the old thermo time switch position).
I also began the cutting of the aluminum stock for the fuel rails. By this time I was rather tired, so I have just cut one side. I plan on tapping the end of them for 3/8NPT, and using adaptors to AN6 all over.
Will post pictures once I am done.
Sunday, July 13, 2008
Weekend Work.

This picture shows the Air temp sensor on the CIS housing, as well, as the coolant level temperature sensor on the fron right of the intake manifold. The 2 bolts that seal what used to be the vacuum switches at the front left of the intake manifold are m10-1.0 metric bolts. I have a nice piece of aluminum stock that I will shape to fit in the hole left by the air valve at the front of the intake. I also chose to keep the air distributor, and will be using some hoses to connect them to the new Air valve that you can see in the bracket that used to hold the warm up governor. I still have some more work to do in the car after all is said and done, specially with the hydraulic pump, and the brake booster. Those will also be taken out, cleaned, and painted.

This picture is taken from the passenger's side. Here you can see the IAC on the side of the housing, how it does not interfere with the throttle linkage, and yet it will fit under the air cleaner housing. I will take out the now superfluos vacuum switches in the firewall to make room for the fuel pressure regulator. Notice the old safety cutoff cable that used to go to the top of the CIS housing. I am going to take that out, and clean up the cabling a bit. I never liked the solution to the cutoff, as if the car flipped, the linkage would stay open, and the cutoff never kicked in.
Tuesday, July 8, 2008
Heating Hoses
The hose against the firewall was routed inside the firewall itself. After taking off the little access cover to the vent system, inside the engine, I found that it was not going to be that easy... It ends up being that I had to remove the vent cover on the passenger side, and what is more, I had to drill out the fastener holding the hose in place, as it was rather rusted. I was going to replace them anyway with new hardware, but it took a bit of time.
After replacing the back hose, I moved over to the front hose. This was fairly easy, as it is only a 4" hose, with two clamps.
In preparation for the intake manifold installation tomorrow, I also cleaned the mating surfaces, and cleaned out the bolt holes. Now all that is left is to assemble the intake tomorrow, with all of its ancillary components.
This would be the first step towards the ultimate goal of replacing the CIS system. The following step is the fabrication of the fuel rails, and all the connections. I have already bought all the parts from Jegs and will start with that part of the project next week. I will post more pics of the Intake Manifold in the car, and all the linkages connected.
Friday, July 4, 2008
Pictures






Thursday, July 3, 2008
Mercedes Benz C107 Megasquirt conversion
I am currently in the process of installing a megasquirt conversion on my 1976 SLC. I have been reading Oughtsix’s conversion, and I have decided to follow his advice almost to the t, except for building my own MS computer. I do not feel confident that I will be able to do a good job welding, as I have tried it in the past, and it has never quite worked for me.
So far this is what I have done:
Removed Intake manifold. I had a severe issue with vacuum loss (traced to a nice hole in the pipe coming from the exhaust for the EGR, and the fact that the Air control valve was stuck in open), and needed to isolate the problem, so I decided to remove the intake to replace those pesky rubber spacers in between the upper and lower manifold. This also helped me to clean, and seal the intake in a much better fashion. I also used Eastwood’s Co. Alumablast to refinish the top of the intake, and it looks so much better.
Had the thermo-time switch rebored for the 3/8NPT pipe thread needed for the CLT. I also took off any of the CIS components (Warm Up Regulator, Idle Control Valve, and the Air Distributor).
Purchased 8 19 LB mustang injectors. Tested the injectors and they do not need to be machined down, and the fit is nice and tight.
I took the old CIS Air intake, and sealed the CIS portions, and took out any moving parts… Including the Fuel Distributor…. Painted it with Eastwood Detail Gray, and drilled and tapped out a nice hole for the IAT... Figured that it would look really nice on the outside of that monster.
Removed all the accelerator linkages, stripped them, cleaned them, painted them with Eastwood black, and reassembled them. Now they have nice and smooth movements, and are not binding.
Bought the idle control box, and a 1992 Jeep IAC valve and tapped out two m6 bolts on the side, and I am using the bracket that used to belong to the WUG for it. Now need to get the right combination of hoses to connect it to the air distributor, and the (now inert) CIS intake. This should work as I am taking nice clean filtered air from the CIS, and through the air regulator am going to the intake manifold after the throttle body. BTW, the reason that I kept the original huge CIS intake was to keep the even bigger Air cleaner on top of it. I will eventually add a cold air intake, but more like the 560’s version that still has the large air cleaner… The reason for this is to have a large filter that allows more air in and gets dirtier less. (And still keep some semblance of originality).
Bought new bolts. As I had cap head hex bolts, I chose to replace them, as they tend to stretch and lose some of their strength after repeated torqueing.
Bought the Relay panel, the CLT, and the IAT from DIY autotune.
Cleaned the V of the engine block, and painted with temp. resistant black.
The idea is that anything that gets touched/removed is cleaned, and if needed stripped, painted, and reconditioned if possible, or replaced.
The plan as of today is to get some parts in (replacing the heater hoses that run UNDERNEATH the intake manifold) before dropping in the reconditioned manifold.
After the intake manifold is in, the injectors with new seals will be put in the car, and the electrical will start. I have decided to use the negative post of the coil for tach input, and wire the fuel pump from the relay board for safety reasons (the 76 had the safety switch on top of the CIS housing, and that got deleted as it would not be used, or useful.).
I will post some pictures of the work so far, and would appreciate any comments, and recommendations. I have found oughtsix’s site extremely helpful, but any other ideas would be greatly appreciated…. And no, there is not talking to me about keeping the CIS, as these systems are not well supported, or understood… They might have been state of the art in 1976, but…. Now, they are just a pain.
I do have a couple of questions though. I still need to find a nice power lead that is on both at run and at crank. I was thinking of using the lead coming from the old fuel pump relay, but are there any other ones closer to the engine compartment? If not, it is not a huge issue, as I need to run cables to the engine anyway.