Fuel Injection Conversion

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=80 BGCOLOR="#000000" TEXT="#F7F7FF" bgproperties="fixed" background="06000500dvldtc.png"> <div> <FONT SIZE="5" COLOR="#FFCC66" FACE="Arial" ><B>  </B></FONT><B>     |     </B><A HREF="index.htm" TARGET="_top" TITLE=" "><U><B>home</B></U></A></div> <div> back to                                                     </div> <bR> <div> <B>By the way, see that list of cars on the left ? They are just there to look at , but not available for sale. I just leave them there as art.   Some cool stuff there !</B></div> <bR> <div> </div> </td> </tr><tr> <td valign="top" width=210 BGCOLOR="#000000" TEXT="#F7F7FF" background="061d2c00dvldtc.png"> <div>                                                   </div> <bR> <bR> <bR> <bR> <bR> <bR> <bR> <bR> <div> <IMG SRC="a6dfabc0.jpg" border=0 width="250" height="188" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> <IMG SRC="a6ffabc0.jpg" border=0 width="250" height="188" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> <IMG SRC="a71fabc0.jpg" border=0 width="250" height="188" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </td> <td valign="top" height=400 BGCOLOR="#000000" TEXT="#F7F7FF"> <div> Fuel Injection Conversion !</div> <bR> <div> <IMG SRC="a359bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Well this is a long story. Fuel Injection. Sure. Let's do a conversion !</div> <bR> <div> Years ago I wanted a Ferrari 308 GT4 & couldn't afford one. I tricked out an X1/9 as my cost effective substitute. At one junction I converted it to Bosch L-Jetronic injection from a later model car. Had to swap the gas tank & wiring harness, cut holes, curse, learn new things & swore I'd never do it again.</div> <bR> <div> Later on I finally got a GT4 & learned that for the tight hilly roads I live on, the X1/9 was a better car, Huh. By then I had sold the X  to an unappreciative owner to raise some cash & he beat it into the ground, A sad story. I spent three years tuning that GT4 to try to make it sing as well as that modified X1/9. I learned how to bore out the Weber carb body air correction  circuits on a Bridgeport milling machine to get rid of the transistion hesitations, ( it would have been too easy if they made that part a changeable jet... ) & figured out that if you made a huge rear sway bar it would finally start to turn in, ( Carefull in the rain ! )  Alas, It threw 2 connecting rods through the side of the block when I was driving in a hill climb in Nevada...........   Oh dear.  That was a bother.  The tow bill home was more money than I had alloted for the weekend, & to pull a 308 motor the transaxle comes out with it. I think the factory book time is 14.5 hours for removal, & that is when they were new with no rust & a couple guys with factory tools. That project took forever. I fell out of my chair when I got the parts quotes. I think a factory gasket set was $1250 & aftermarket was around $800. Ow.  It got worse from there. Ran great when I was done, but the tariff was devilish........</div> <bR> <div> Back to the fuel injection plot:</div> <bR> <div> A year or two ago I converted a<A HREF="id116.htm" TARGET="_top" TITLE="Variety"><U> Citroen I bought in France</U></A> to a throttle body fuel injection setup. It was mainly to prove that all things really have a common denominator. I tried to take parts from as many different countries as possible. A Peugeot fuel pump, German temperature senders, A Suzuki throttle body, Italian relays, a computer from a 3 cylinder GEO Metro, ( Just to prove you can run a 4 cylnder car on a three cylynder black box, )  & hacked into the computer with a soldering iron & an attitude.  I figured out how to generally fine tune the mixture, & used a tone pot from a Gibson les Paul with a big fat weighted knob from an old Tube Macintosh stereo amp to dial it in.  Put that knob in the dash where the choke used to be, & what a difference ! The hill I drive home used to require  2nd gear, & it now climbs up in third.  The power used to die off by 4000 rpm, & now it wakes up at 3850 & pulls off the tach. It also gets better mileage. Wow !</div> <bR> <div> Of course I was so wrapped up in building it between customer projects I never fully documented it.</div> <bR> <div> Darn it.</div> <bR> <bR> <div> For the next conversion I'll try to keep some photos.</div> <bR> <div> How about multi port injection this time ?</div> <bR> <div> For a pancake motor like this Citroen GS it will probably have improved cold running & throttle response as the injectors will be right on top of each inlet valve instead of having one central injector on top of long runners.</div> <bR> <div> OK, </div> <bR> <div> Here goes................</div> <bR> <bR> <div> Hey, Look at that nice late model inlet manifold. Let's use it as a donor.........</div> <bR> <div> <IMG SRC="a389bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> OK, Time to whip up some injector holders.</div> <bR> <div> <IMG SRC="a3a9bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> The lathe saves the day</div> <bR> <div> <IMG SRC="a3c9bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Coming along, but we need to bevel the holders to match the inlet tubes. Now the mill comes in handy,.......</div> <bR> <bR> <div> <IMG SRC="a449bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Look at that: Closer to glory</div> <bR> <div> <IMG SRC="a3e9bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Check out the cool bevel I got on the injector holders:</div> <bR> <bR> <div> <IMG SRC="a429bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> OK, a few holes in the inlet manifold</div> <bR> <bR> <div> <IMG SRC="a469bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <bR> <div> Solder, braze, weld or TIG ?</div> <bR> <div>  I decided to braze, & pre tinned ( buttered ?) both sides first with flux & brass. Heat the metal before you apply the flux for better results.)</div> <bR> <div> <IMG SRC="a489bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Taking a break to bang on an old les Paul like the one I stole that tone pot out of for the mixture controll knob.</div> <bR> <div> <IMG SRC="a5ae0680.jpg" border=0 width="480" height="360" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Hey, look at that ! The manifold is coming along.</div> <bR> <div> <IMG SRC="a4a9bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Uh oh. need some inlet tubes for the fuel supply.</div> <bR> <div> <IMG SRC="a4c9bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> I bent & flared brake line, & then silver soldered the junctions. I pressure tested with compressed air through a regulator & it all looks pretty good.</div> <bR> <div> <IMG SRC="a4e9bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <bR> <div> <IMG SRC="a509bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Will it ever end ? How about an O2 sensor in the exhaust manifold.........</div> <bR> <div> Had to drill a big hole, find a threaded bung, & braze that thing in with some brass & flux.</div> <bR> <div> Once again I am trying to use parts from as many different sources as possible to prove that al of this stuff is compatible as it is simply physics.</div> <bR> <div> All of these pieces can communicate together as electron flow & computer pulses share the common language of logic.</div> <bR> <div> This Oxygen sensor came out of a Husqvarna from Sweden. Chain Saw or Motorcycle ?   ( I  don't know, I just found it on Ebay........)</div> <bR> <div> The fuel pump ? Jaguar ! Some Porsche sensors, an American computer, Japanese injectors...........</div> <bR> <div> <IMG SRC="a529bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Need to get a hunk of aluminum to adapt the throttle body. That 52mm hole was difficult to make. ( 4 jaw chuck in a lathe.)</div> <bR> <div> <IMG SRC="a549bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Swiss cheese that thing. Here's the measuring process to adapt a computer controlled Idle air valve stepper motor. ( Got the stepper motor from a Jeep. Support American industry...)</div> <bR> <div> How cool will it be if it fires up & idles at 1250 cold without ever touching th gas pedal ?</div> <bR> <div> <IMG SRC="a569bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Coming together</div> <bR> <div> <IMG SRC="a589bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> OK, reflect on this chart for a minute.</div> <bR> <div> <IMG SRC="a5946850.jpg" border=0 width="582" height="389" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <bR> <bR> <div> The interior comes out to install a wiring harness for the computer.</div> <bR> <bR> <div> <IMG SRC="a5c9bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Here's the overview in the driveway</div> <bR> <div> <IMG SRC="a5e9bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Learning how to run a computer controlled ignition I needed a spark generator on the test bench. This is an old bevel drive Ducati coil with time period correct</div> <div> braided ignition wire I found at the Padova swap meet. If you ever get a chance, the meet is late October or early November every year & it will melt your neurons</div> <div> if you like Italian cars.  Biggest swap meet of the year in Italy. I recommend a Google search to get you fired up. </div> <bR> <div> <IMG SRC="a6007f40.jpg" border=0 width="519" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Computer testing & programming</div> <bR> <div> <IMG SRC="a679bf40.jpg" border=0 width="667" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Gibson the cat reflecting on it all in the back of a Flaminia.</div> <bR> <div> <IMG SRC="a758ae80.jpg" border=0 width="650" height="488" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <div>  <A NAME="gibson"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="1" ALIGN="bottom" WIDTH="1" HSPACE="0" VSPACE="0" ></A></div> <bR> <div> So here's an interesting thought:</div> <bR> <div> If you have contemplated an injection conversion, it becomes obvious that a high pressure fuel system ( maybe 40  psi injected, vs 4 psi carburetted ) usually</div> <div> has a return to the fuel tank. If an early carburettor system has no tank return , plumbing one in can be an event, ( I never liked welding on gas tanks reeking of petrol fumes with a torch anyway....)</div> <div> Several options:  Remove the fuel gauge sending unit & silver solder in a u bend & return line, solder or braze a return line into a metal fuel filler line ( Sounds dangerous to me, I wouldn't do it without removing & flushing everything first, ) or try this idea I came up with:</div> <bR> <div> <IMG SRC="a69bca60.jpg" border=0 width="700" height="422" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <bR> <bR> <div> Keep the original mechanical fuel pump. Starting with the line out introduce high pressure fuel line. Regular 5/16 carburettor fuel line is cheaper, but will blow out 2 years down the road & burn your car to the ground. You must get fuel line for injection purposes !</div> <bR> <div> Run this line into a 3 way T junction & feed an injection fuel pump.  Feed all the injectors, & end up in a regulator ( I used a Subaru one. All this stuff is pretty much interchangeable. There's warning labels & cautions everywhere as we are a fear based society, but from a point of physics & mathematics, close works pretty well most every time. ) run the regulator overflow back to the T junction & feed the EFI pump.</div> <bR> <div> In a previous experiment in the driveway I know that if you block off an injection pump with a pressure gauge it will peg the gauge at 80 psi, blow the line off & spray gasoline everywhere.</div> <bR> <div> Cautiously for this installation I used compressed air ( necked down with the regulator from a leak down gauge to 10 psi ) to check for leaks & functionality.  A squirt bottle of soapy water showed no leaks, but as I wound up the regulator to 60 PSI the pressure was the same in all circuits. A bother to rig up all those gauges, but better than catching a car on fire later. </div> <bR> <div> Huh. So much for my great idea. I know my regulator blows off at 38 psi, but with an air loop there is no regulation.</div> <bR> <div> Let's try it with pumps hooked up & gasoline. Will the loop run at 100 psi ?  Will it blow off the hoses and cover everything in gasoline ? Get a fire extinguisher just in case, & let's find out.</div> <bR> <div> Nah. It works great. The injector lines hold a steady 38 psi, & the injector loop circulates at 0 psi. Cool ! When you stop the electrical pump, the residual 38 psi stays on the injectors, & the pressure in he T junction climbs to the 5 psi the mechanical pump would normally hold.</div> <bR> <div> How about that !</div> <bR> <div> What a time saver.</div> <bR> <div> If you lived in a hot area & had vapor lock concerns this may not be an optimum solution, but it sure beats pulling out & welding a gas tank.</div> <bR> <div> Remember ( as my lawyers tell me ) this is all just information, not advice. I don't recommend that you try any of these ideas, & if you do, carry 2 fire extinguishers & don't blame me for any surprises.</div> <bR> <div> As Jon Norman once said, you always have fun, sometimes it just not the type of fun you thought you would have............</div> <bR> <div> But how cool is it that the loop will cycle at basically 0 psi with the pump running full time. I feel safer already.</div> <bR> <bR> <bR> <bR> <div> OK: Starting to assemble pieces on the car instead of on the test mule motor.</div> <bR> <bR> <bR> <div> <IMG SRC="a7752f40.jpg" border=0 width="594" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <bR> <div> Looks like I'm going to need some fuses. Time to make some way to organize them</div> <bR> <bR> <div> <IMG SRC="a7962f40.jpg" border=0 width="610" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <bR> <div> Alright. That worked out OK</div> <bR> <bR> <div> <IMG SRC="a7bf1f40.jpg" border=0 width="497" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Hey: the car is outside. That must mean it runs, as I can't get it off the lift if the hydraulic suspension has deflated.</div> <div> It fired up instantly & settled into a perfect idle.</div> <bR> <div> <IMG SRC="a7f8ae80.jpg" border=0 width="650" height="488" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <div> Yeah !</div> <bR> <div> Open the throttle & it  bogs though.</div> <bR> <div> Huh.</div> <bR> <div> A bit of sleuthing & I discovered that inside the throttle position sensor ( TPS)  there are only two switches instead of a rheostat.</div> <bR> <div> Bosch L-jetronic systems, licensed around the world use that system. Later model injection systems almost universally use a rheostat.</div> <div> It never occured to me that my late model Subaru Turbo TPS was the early type.</div> <bR> <div> Of course I never checked into that before I spent all those hours machining brackets, adapters,  & linkage bits..............</div> <bR> <div> Oh well. Time to find one that will fit. Off to visit the local car shops & a wrecking yard.</div> <bR> <div> Of course none of them fit. All the rheostat style TPS modules have a different drive mechanism.</div> <bR> <div> Darn it. I'll have to fabricate a converter. I'm ready to drive this car, not keep making stuff for it. Not to mention the customers want their cars worked on.</div> <bR> <div> Somehow it's already Thursday morning & I thought I'd be done with this project by  last Sunday night.....</div> <bR> <div> OK. Get to it. First finish that Lancia Flavia PF coupe that's on the lift.</div> <bR> <bR> <bR> <div> Back again.</div> <bR> <div> I now discover all the modules that fit my needs turn counter clock wise & the setup I have turns clockwise.</div> <bR> <div> If I mount a new one it will have to go on the other side of the butterfly, and that means it will run into the oil filter & the spare tire mount.</div> <bR> <div> All that working machining the manifold & the car actually runs ( at idle) but I have hit another brick wall.</div> <bR> <div> This is not a problem, it's an opportunity.</div> <bR> <div> I wonder how I'll solve it..........</div> <bR> <div> <IMG SRC="a818ae80.jpg" border=0 width="650" height="488" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Next day:</div> <bR> <div> OK: I figured it out.</div> <bR> <div> Remachining a new pedestal for another throttle body, & building a new linkage seems like too much work. All of the variable resistor TPS I find turn the wrong way. If I mount them on the other side of the shaft so they turn properly, at the very least my spare tire won't fit anymore. There must be a simple solution.</div> <bR> <div> Heck, the darn thing is just a variable resistor carrying a 5 volt signal with no amperage of consequence to a computer.</div> <bR> <div> I'll just make something that will fit on the correct side of the shaft. How hard could it be ?</div> <bR> <div> What about that Gibsone Firebird in the studio? I changed out the volume potentiometer on that guitar to get a different tone.</div> <bR> <div> I just rustled around the electronics workbench at home, found the old volume pot, whipped up a bracket, made a little connector shaft on the lathe & bolted it on.</div> <bR> <bR> <div> <IMG SRC="a8cf5f40.jpg" border=0 width="501" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Works pefectly.</div> <bR> <div> Wow !</div> <bR> <div> I've now got fuel injection !</div> <bR> <div> What could possibly go wrong next ?</div> <bR> <bR> <bR> <div> Mmmmmmmm..................</div> <bR> <bR> <bR> <div> Uh oh.  What's this? :</div> <bR> <div> <IMG SRC="a834ef40.jpg" border=0 width="590" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <div> Hmmm.. It seems that my idea for the fuel return loop wasn't so hot. </div> <bR> <div> Actually it was too hot.</div> <bR> <div> The fuel pump was warm to the touch, & then it went to 120 degrees while running. Then the car stalled due to vapor lock.</div> <bR> <div> Darn it !</div> <bR> <div> Now I have to rig up a return line to the gas tank.</div> <bR> <div> Above is a picture of the fuel gauge sending unit I found lurking in the trunk.</div> <bR> <div> Maybe I could somehow put a return line in there so I won't have to remove the gas tank.</div> <bR> <div> Not much room for another pipe though.</div> <bR> <div> It's also held in with an unobtanium clip that looks like a one use only job.</div> <bR> <div> What happens if I break it ?</div> <bR> <div> Huh.</div> <bR> <div> Will it come out ?</div> <bR> <div> Let's take a break.</div> <bR> <bR> <bR> <div> I'm starting a new business to sell things  I design & manufacture called Scuderia Zombie. There's going to be lots of cool stuff coming out ( when I find the spare time.....)</div> <bR> <div> Flavia wheel bearing wrenches perhaps ? I've prototyped a delicious 5 channel datalogger for vibration analysis that uses modern technology from several different fields, hopefully smoothly integrated.............. Another good one on the bench is the Zombie Love Box, a Cool guitar amplifier gizmo that has some good looking architecture & great tone.</div> <bR> <div> Anyway, got to build the brand & all that. I came up with this design for a rear window water transfer decal.</div> <bR> <div> The undead thing is about bringing old mechanical things back to life.</div> <bR> <div> I'm building a website for the project with lots of cool photos of old things in fields & dark garages too.</div> <bR> <div> More on that soon.</div> <bR> <bR> <div> <IMG SRC="a8861ef0.jpg" border=0 width="609" height="239" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Back to the task at hand.</div> <bR> <div> I got the fuel sender out with no destruction.</div> <bR> <div> Here it is with a return line made from 1/4 inch brake line that I bent & was getting ready silver soldered on.</div> <bR> <div> The solder wouldn't stick, that nice amber brown fuel sender caught fire & burned like movie film. </div> <bR> <div> Aw shucks.</div> <bR> <div> After I took it apart ,remanufactured  it, & calibrated the gauge, the piece was now too big to fit back in the gas tank.</div> <bR> <div> Oh come on. I just want to drive it.</div> <bR> <div> Back to the drawing board, I took it all apart again & re-engineered it.</div> <bR> <div> Works fine, no leaks, no more time in the day.</div> <bR> <div> Off to dinner.</div> <bR> <div> <IMG SRC="a85e2f40.jpg" border=0 width="482" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Here's the return pipe running underneath the chassis. ( It's the shiny new one.</div> <bR> <div> It actually turned out to be a fairly clean solution.)</div> <bR> <div> <IMG SRC="a87eef40.jpg" border=0 width="494" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Saturday:</div> <bR> <div> So how's it run ?</div> <bR> <div> Darn great actually. Just took it out on the freeway tonight while I tried to dial in a fuel map.</div> <bR> <div> Pulls hard, idles really well, starts instantly when you reach in the window & twist the key without having to touch the gas pedal. </div> <bR> <div> I programmed that little stepper motor to open up a bit for 6 seconds & then ramp down to a nice smooth idle. </div> <bR> <div> That's exciting.</div> <bR> <div> Just like a real car.</div> <bR> <div> <IMG SRC="a8e79f40.jpg" border=0 width="633" height="500" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> Overall I'm thrilled with the improvement.</div> <bR> <div> Time to put away the tools, make some notes, fine tune it a bit & then..............</div> <bR> <bR> <div> Work on a Flaminia Zagato that's coming in this week. Light green metalic mist.</div> <bR> <div> I always like it when the cars arrive in interesting colors.</div> <bR> <div> Cool !</div> <bR> <div> See ya.</div> <bR> <bR> <div>  <object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/zIhnxPdLsVA?hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/zIhnxPdLsVA?hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>  </div> <bR> <bR> <bR> <bR> <bR> </td> </tr></table></body>