This is a record of the parts, trials and tribulations from my swap from a Weiand Stealth Intake / Carter Carburetor to a Single Plane fuel injection in my '80 El Camino.
06/05/2006: WOOHOO... a real live work log. I've finally moved from the parts-gathering phase to the parts-installation phase. I got the Holley intake, rails & injectors in 2002!
My game plan is to get the MS1 reading all inputs from the engine (and possibly upgrade to MS2) before I swap the Carburetor/Intake for the Fuel Injection parts. I also plan to have the fuel system plumbed beforehand such that the current fuel feed line will be changed to fuel return duty and the new steel 3/8 line will feed the Injection system. I plan to do he swap in this order so I can be sure each piece is working before the actual conversion - and I'd like to minimize downtime. The Elky isn't a daily driver, but it's too fun to drive to have it out of commission for any length of time. (Note this is the gearhead definition of "fun"... it's loud, smelly, doesn't have a radio or A/C... fun = banging gears winding out a 406 I built from a pile of parts!).
Over the Memorial Day weekend I printed the MegaManual which I read on the beach 
. The manual is somewhat tech-heavy but I'm skipping the parts about building the ECU itself (except when the manual refers back to those sections). Even if you plan to use MS2 from the start, it is best to read both MS1 and MS2 sections (starting with MS1) because the MS2 sections read as though you are already familiar with MS1. I also tested the MS1 with the stimulator: the sensors appear to be reading normally.
This past weekend I installed the relay board, relay board cable and wired them to power up the MS1. So far, so good. The map, baro and voltage look right. Now to wire the rest of the sensors.
06/11/2006: After a bit of study I determined the driver's side would be the best route for the new fuel feed line (more or less following the fuel vapor line). The 30" steel line already had a 90° bend on one end so I used it back at the rear frame crossmember (this piece runs east to west). Other than the 90° bend the bending was done by hand; it seemed to work better in making the wide curves I wanted. I used the body of the car to bend around in some spots. The first 51" section connects around the same area as the emergency brake connector and then curves into the frame rail. The next 51" follows the frame rail and then curves inward towards the engine, terminating at the proportioning valve (a 60" section might have been better here). (I'll probably get rid of all this description when I add photos.)
I've been struggling with the best way to connect the 3/8 inverted flare tube (5/8-18, 45 degree) to the Holley rails (-6 AN) on the engine, and the 16mmx1.5 o-ring filter at the tank. Aeroquip 4739-6B 5/8-18 to barb fittings (Napa/Weatherhead 10006B406) will NOT work due to the depth of the threads; the fitting has deeper threads than the tube nut. Hayden 240390 is a transmision cooler adapter kit that includes one male 5/8-18 to barb fitting and one female 5/18-18 to barb fitting. This will allow me to connect the Aeroquip FC332-06 socketless hose to the steel tube. The Holley rails include a -6 to barb adapter. At the filter I may use Dorman / HELP fuel line repair kits 800-153 (18") and/or 800-170 (4"). The fuel line repair kits seem to be the least restrictive solution.
01/14/2007: How did seven months fly by with no updates to this work log? As a father's day gift I was given time to work on the El Camino. Since I didn't have all the parts needed for the injection swap I turned my attention to the exhaust. I yanked the rusty full length headers that were on the car and put on shorty headers. How did this take so long? I toyed with the idea of adding the turbo I've been planning, but in the end I decided that the injection would be a project enough without adding the complexity of a turbo (in hindsight this was a wise decision).
Over the New Years holiday I wired in all the sensors. Most were wired with wiring scavenged from a TBI harness from an '86 Monte Carlo. With the Carter carb the narrow band O2 read way rich, as I suspected. The carb was a used part that was a temporary solution until the injection. I did the intake swap without too much trouble. I made sure the distributor was pointing to the #1 cylinder, however I could not orient the HEI distributor the same way with the Holley intake. A large cap HEI will barely fit! I had to point the vacuum cap towards the firewall... and the advance weights seem to be opening erratically. An MSD 85551 may be a more reliable distributor solution (the distributor is only a trigger, my ignition is an MSD 6AL equivalent).
I wired the injectors with 14 gauge TXL wire using the MSD injector plug kit. This was a major hassle because the TXL wire is so thick I had to shave it down to fit the connector. (Also I'm slowly improving in the soldering department... thankfully MSD included extra wire terminals).
Note: I took the prices off the "Parts Acquired" section. Eventually the current prices will be outdated. By watching for deals on parts (over 5 years!) I spent around $500 to get to this point (not counting the parts I didn't use, which will go to eBay). A wide band O2 will add $200 at a minimum (and a wide band is needed for high load tuning). I think $1500 is a good estimate for how much adding fuel injection to your small block will cost. (Makes you wonder if buying a used LT1 isn't a better idea... I do have more displacement...)
PHOTOS (mid swap):
04/13/2007: I've had periods of great progress. The good news is the 406 fires up and runs well. The ignition is still an issue: I believe the advance weights in the HEI are getting stuck in the out position, causing the idle to hang at 1000rpm. A blip of the throttle allows them to come back in and the idle comes down to the normal 700rpm. I've waited to convert to spark control with the Megasquirt, mainly to make sure the fuel was dialed in and also to figure out how I wanted to implement spark. I think I'm going to use a 7 or 8 pin HEI, with the coil out wire feeding the Holley ignition box.
Mistakes I made that you should avoid:
LC-1 Wiring Notes (PLEASE EMAIL ME IF THERE ARE ANY INACCURACIES!)
Ground the LC-1 and the MegaSquirt together. This is to prevent a voltage differential and will ensure accurate readings. Don't ground it to the battery. Direct engine ground is best, with the blue ground separate from the green & white. Also be sure to put the 5 amp fuse on the power for the LC-1. You can program the analog output you are not using to some constant voltage to check the LC-1.
| Part | Part # | Source |
|---|---|---|
| MegaSquirt I Assembled ECU | MS230-C | DIYAutotune |
| MegaSquirt Stimulator | MSStim-C | DIYAutotune |
| MegaSquirt Relay Board | MSRelay-C | DIYAutotune |
| MegaSquirt-II Relay Cable | MSRelayCable | DIYAutotune |
| MegaSquirt Tuning Cable (DB9 Straight Thru) | TuneCable6 | DIYAutotune |
| Coolant Temperature Sensor & Connector | CLTIATwConn | DIYAutotune |
| Inlet Air Temperature (IAT) Sensor & Connector | IATwConn | DIYAutotune |
| Holley MPFI Intake | 9901-101-1 | Parts Warehouse |
| Holley Fuel Rails | 9900-172 | Parts Warehouse |
| Holley 36lb. Fuel Injectors (NA) | 522-3608 | Parts Warehouse |
| Ford 42lb. Injectors (boost) | M-9593-F302 | Internet Sale |
| Holley 4 Barrel TBI (Includes TPS & IAC) | ? | eBay |
| Accel Blueprint Large Cap CCC Distributor (not used yet) | 9109 | eBay |
| Spectra Fuel Injection Fuel Tank* | GM517D | eBay |
| (2) 51" 3/8" Steel Brake Lines | ? | Pep Boys |
| (1) 30" Steel Brake Line | ? | Pep Boys |
| 3/8" Internal Flare Couplings | ? | Pep Boys |
| Fuel Injection hose clamps | ? | Pep Boys |
| Fram Fuel Filter | G3727 | Parts Warehouse |
| Earls Adapter: Male 16mm-1.5 to Male -6AN** | 991955 | Parts Warehouse |
| Fuel Pump Pad Blockoff Plate | ? | Parts Warehouse |
| Oxygen Sensor Bung | ? | Parts Warehouse |
| Aeroquip Socketless Hose | FC332-06 | eBay |
| Hayden Inverted Flare to AN Barb fittings | 240390 | Advance Auto |
| 255lph Walbro Fuel Injection Fuel Pump | F20000169 | Full Throttle |
| Fuel Pump installation kit | 400-1016 | Full Throttle |
| Fel-Pro Intake Manifold Gasket | 1205 | Parts Warehouse |
| Innovate Motorsports Lambda Cable Standalone Wideband O2 Controller With Sensor | LC-1 | eBay |
| Injector Pigtails | MSD 2400 | Parts Warehouse |
You'll note the MegaSquirt part numbers are assembled units. While I believe I would learn more about the system if I built it myself, I also think that the hours required could be put to better use (the assembled MS2 ECU is only $160 more... at 8 hours that works out to $20 an hour - but it would probably take me longer than 8 hours) I may build an ECU later on, but right now I'd like to know the parts were built by someone who knew what they were doing.
| Part | Part # | Source |
|---|---|---|
| MegaSquirt-II Daughterboard | MS2-DB | DIYAutotune |
| 1.5" Fuel Pressure Gauge | ? | ? |
| IAC Valve Connector (alternate Conduct Tite 85135) | ds-iac_Conn | DIYAutotune |
| TPS Connector (Conduct Tite, alternate Ecklers 30542) | 85115 | ? |
All MegaSquirt components are to be purchased from:
