Thanks for the kind words everybody, much appreciated from such an
extinguished distinguished bunch!
So now with the welding finally complete I can move onto part 4 - fuel injection!
Sometime before the need to weld became apparent I had fitted Megajolt, which later got swapped for a Megasquirt.The Megasquirt had been running ignition only using Ford EDIS coilpacks. I also fitted a "Spartan2" wideband sensor from 14point7.com to keep an eye on the mixtures.
So with the main brain of the thing fitted, it was time to get the fuel side up and running. As the car was (and still is) my daily, i worked through a list of things to fit/solve before I took the final step of swapping inlet manifold:
- Sort out the mounting of the air filter
- Work out the throttle “see-saw” mechanism to convert from the standard P6 pedal to cable throttle.
- Run extra wiring from boot to engine bay
- Mount MS properly (I had previously just cable-tied it to some stick on pads affixed to the fuel tank)
- Fit a better auxiliary fuse box
- Refurb some later rocker covers
I had an air filter can from an SD1 which I had previously cleaned up with electrolysis:
After cleaning it had a couple of small holes:
I sealed those with epoxy and gave it a few coats of black, before fitting it up in the engine bay. As always I used existing holes and made a bracket that came off of these to bolt the filter can to:
Then, moving onto the throttle. The RV8 P6's use a throttle rod/linkage mechanism all the way to the carbs, whilst the later 4 cylinder cars used a "seesaw" mechanism which converts this rod and linkage to cable halfway along. I decided to fashion my own version of this using what I had to hand, and anyone of a sensitive nature should look away now!
This bolts in place of the old bracket that the final bit of throttle linkage used, again avoiding the need to make new holes in the car.
I pimped up some later style rocker covers:
Because the MS had been in and running the ignition for some time I knew that I had a solid install with no resets or other issues. For the fuel injection I had to run a few more wires from the boot to the engine bay:
Injector 12 volt feed
Injector Bank 1 ground (Switch to ground by MS)
Injector Bank 2 ground (Switch to ground by MS)
Throttle Position Sensor (TPS) VREF
Throttle Position Sensor Signal
Coolant Sensor (CLT) +12v
Inlet Air Temp Sensor (IAT) +12v
Idle Air Control Valve (IACV) 1
Idle Air Control Valve 2
Idle Air Control Valve 3
Idle Air Control Valve 4
Shared Sensor Ground, TPS, IAT, CLT (Back to Megasquirt)
The drivers side seats and carpets were removed to give access to everything for routing the cables. I ended up laying out the individual wires across the front garden, tying one end off to an axle stand before beginning the laborious task of spiral wrapping everything. The wrap keep things neat, and protects the cables from chafing. It also gives you one larger cable to run, rather than having to run each one individually. I followed the main battery lead to the front of the car, before diving across behind the dash. Everything was coiled up and left in the passenger glovebox ready for when it would be needed:
In the garage I had been getting on with sorting out the engine end of the loom:
I also ended up figuring out a way to mount the MS unit more securely in the boot. Again to avoid drilling holes I made up an aluminium framework that was riveted together and then clamped to the tank straps, and the auxiliary fuse box and fuel pump relay were fitted to this too:
With all of that having been completed over a period of weeks it was time to see if the sensors were all going to give sensible readings, so the engine end of things was lashed together on the passenger seat:
Everything looked sensible and I managed to also figure out the settings for the idle air stepper too.
The only things left to do now were to fix the fuel gauge - it had never worked since I got the car, and I suspected that my economy *might* drop off for a bit whilst I was tuning the thing. Better for all concerned if I knew how much fuel I had onboard then!
This meant taking the tank out:
And then the sender out of the tank:
Oh yes, thats a float fuel of fuel then, not much of a float really!
Luckily the float from a series Landrover is a direct replacement, and we have a few Landrovers in the family! The sender was tested by waggling the arm about, but it was still giving intermittent readings, so I opened it up and gave it a clean. I then bent the contact slightly so that it was applying a little more pressure. On reassembly it worked perfectly
So then this happened:
Leaving this:
which became this:
Then it started going back together again:
Until this, tada! (and no, it's not a 4.6, and it's not a Land-Rover either, even if the plenum does say otherwise
)
Initially I just gravity fed the EFI pump, before the fuel was sent through a filter and along new nylon hardline to the front of the car.
With all this in place it was time for the first start, and sure enough it started on the first go! However it oscillated wildly between 500 and 2600rpm, up down, up down, up down… a few minutes later working through the MS menus on my phone and I had turned off wideband feedback, upped the fuel and then turned off overrun fuel cut. Success! I now had a stable idle, of 2600rpm…
Some 20 minutes and multiple restarts later and I had got the idle air control valve setup properly and the idle at a more respectable (and neighbour friendly) 750rpm. I could now begin tuning…
This however proved to be problematic, first of all the car was jerking a lot on applying the throttle. I soon diagnosed this as a faulty throttle position sensor, giving erratic readings. To get round this I switched the acceleration enrichment to fully MAP based and therefore ignored the TPS. Next issue was that my initial fuel pump setup was obviously not up to scratch. The pump could be heard cavitating and became incredibly noisy after a mere 20 miles or so!
This led me to add a swirl pot to the system, and replace the EFI pump. I purchased a 1 litre unit from obp solutions but try as I might I could not find anywhere to get it to fit under the car without being too close to things that were hot/rotating/moving. It therefore ended up in the boot, fed by my original facet silvertop pump under the car. This led me to having to drill a few holes, argh :
This seemed better and the car ran fine for a couple of weeks before this happened:
The fuel pump got incredibly noisy and died on my way into work. I got the big yellow taxi home and realised that I had plumbed the swirl pot in wrong! I knew what I wanted to do, but must have got a couple of the pipes mixed up during installation. The order should be:
Top > Return to tank (fuel out)
2nd down > Return from fuel rail (fuel in)
3rd down > Feed from main tank (fuel in)
Bottom > Outfeed to EFI pump (fuel out)
I had mixed up the feed from main tank and the return to tank, so I probably had a swirl pot half fuel of air!
The low pressure pump was also running really fast all the time, so I decided to restrict the return from the swirl pot to the tank, this had the desired effect and the pump could be heard to run fast and then slow down as it used to with the carbs fitted.
After a little while I realised that the plenum was rubbing on the underbonnet insulation quite badly, so I ended up swapping the pimping looking 4.6 one for a 3.9 one which is lower at the front. I preferred the look and more compact idle air valve setup of the later plenum, but needs must and it got rehomed on my Defender anyway
:
So with that I am almost up to date!
. The previous "repair" consisted of a repair panel that had been welded over the existing structure, without removing any of the rust. The welds were sketchy and I was surprised that the top links hadn't sheared off under my sometimes enthusiastic approach to roundabouts.
)
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