850 Sport Coupe series 2 track car.

Discussion in 'Rear-Engine Fiats' started by ramona300, Oct 1, 2015.

  1. motoTrooper

    motoTrooper True Classic

  2. ramona300

    ramona300 True Classic

    Thanks for the reply. The AMR500 is a Roots type blower so the boost starts very low. Changing the pulley size is the only real way to do this.
     
  3. ramona300

    ramona300 True Classic

    Changed the pulley size on the supercharger, now has a ratio of 1.46:1. Engine runs nice, just doing some no load tuning of the maps. From the Data logs it seems the boost is about 8psi but will know for sure after a visit to the dyno again next week. The inlet air temperature is now 80c which is a much better temperature than 150c.
     
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  4. motoTrooper

    motoTrooper True Classic

    Nice work, I love your car and what you're doing with it. Keep posting videos of it, curious how the dyno session works out.
     
  5. ramona300

    ramona300 True Classic

    Some whine with that sir?
    Follow up dyno day yesterday with the boost now at 8psi instead of 19psi. Dropped a lot of torque but whp is up slightly at 7760rpm. Due mostly I'm sure to the lower air intake temperature, now a max of 88c versus 150c with 19psi. Water/meth injection later in the year will help.
    Off to Winton in Victoria for the Fiat super sprints {Nationals] end of next week.
     
    NM850 likes this.
  6. ramona300

    ramona300 True Classic

    Short video from the first run at Winton. My first time at Winton and the cars first run on a full sized circuit. I never got to grips with some of the corners, especially those just after the sweeper! Many laps are required at this circuit to get it sorted. Took it fairly easy and never used more than 6500 rpm and about 70% throttle. Second run after a couple of laps I left the track at corner 10 over the ripple strip. This strip has a sharp deep drop off on the inner edge and I hit the floor pan very hard. Lap or so later I had the occasional backfire from the exhaust and a series of brief engine failures. Car started immediately after each stop and I'm certain it was ignition. Third run I had more engine failures and I decided to put her back on the trailer.
    When I got home I plugged in the laptop and run the engine and data logged but found no faults. I did notice the WUE light took awhile to go off and when I checked the settings found the warm up enrichment was still on at 86 degrees C. I reduced that to about 70. When I watched my videos of the day I was surprised to see the radiator temperatures on the Davis Craig controller were 75c, the temperature is set to 85c and the controller maintains the temperature normally by cycling the pump or turning on the fan. No idea what temperature the Microsquirt was seeing but it's possible the WUE was coming on and adding fuel. I will be installing an inline thermostat. Mini Cooper S radiator is too efficient.
    Also snapped off a welded lug on the left rear suspension where I have a Dyneema strop to stop the suspension tucking under. The left driveshaft boot has also let out a heap of transmission fluid. There is gear box oil everywhere on the left hand side of the engine bay and a fair bit on the 36:1 timing wheel and Ford pick up. There is about a 1 mm air gap there normally but I'm starting to think some of the oil may have upset the signal and caused the intermittent failures.
    Car has done 145 miles now on the rebuilt engine and about 20 miles since the replacement pistons and new rings.
     
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  7. motoTrooper

    motoTrooper True Classic

    Thanks for sharing this, very smooth driving. Despite you holding back I could get a sense for the myriad of things you must be focused on. Traction, line, braking zones, and the omniscient awareness of mechanical performance.
     
  8. ramona300

    ramona300 True Classic

    Had plenty of power to spare. Greatest concern was the handling. Using Avon formula ford racing rubber and they were particularly squirmy on the first lap [not in the video]. Seemed to have too much understeer. Front suspension is wishbones and coil overs, rear is Abarth 1000 coils and stock anti sway bar. Yesterday I removed the plastic coil seat from the rear springs and the rear sits about 30mm lower now. Probably about 2 degrees negative camber on the rear. I'm planning on fitting the same size tyres on the front as the rears as well.
     
  9. ramona300

    ramona300 True Classic

    Yesterday I ran the engine till it was nice and warm then dribbled some oil over the induction pick up to simulate the gearbox oil leak problem. Blipping the engine resulted in several backfires and the engine ran rough but did not stop. Under load the engine probably would have stopped though I reckon. I'm fairly confident this was the problem at the sprints. The induction pick up slopes down to the 36-1 wheel and the oil runs down to the tip perfectly! An electrical tie about 5mm from the tip with the joiner down would probably cause the oil drops to fall clear. I will probably devise some sort of shield to keep oil clear though just the same.
    Also had the rear suspension apart and removed the plastic seats for the coil springs so now the coils are making a metal to metal contact. Coils are from Germany and are what's used in Abarth 1000 coupes. Car sits about 40mm lower in the rear now and is obviously what I should have done when I first installed the coils.
     

    Attached Files:

    motoTrooper likes this.
  10. kmead

    kmead Old enough to know better

    Location:
    Michigan
    You likely want a pulley more in the 120mm range (perhaps even larger but there is likely inefficiency so its likely not linear) for a reduction in boost. The temp is going to require an inter cooler to disappate some of the heat of compressing the air. How you will fit that in there is beyond me :)
     
  11. ramona300

    ramona300 True Classic

    Boost is down to 8psi now Karl. Air intake is about 88 degrees and is acceptable. Intercoolers only lower the temperatures a small amount. Water/Meth injection will be installed in the next few months. That will make a massive difference.
     
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  12. ramona300

    ramona300 True Classic

    Formula Ford Avons. Tyre on the right is the front and the tyre on the left is a rear tyre now going on the front. Lot more rubber! Had to roll the fender quite a bit. The side view shows the new stance. Weight is on the front though the wheels are off the trailer. Measured the camber at the rear at 2 degrees negative.
     

    Attached Files:

  13. ramona300

    ramona300 True Classic

    Hillclimb yesterday. Made some modifications to the nose cone!

     
    mkmini, Chaostoy and motoTrooper like this.
  14. JimD

    JimD Waiting for Godot... Moderator

    Location:
    Missouri, USA
    Ouch. Good to see that you were OK. :)
     
  15. That thing looks and sounds fun, but I'm sure I'd have a hard time keeping it pointed the way I intended to go as well! (Even after learning how to shift with my left arm)
     
  16. kmead

    kmead Old enough to know better

    Location:
    Michigan
    Bummer. Looked like a good time though.
     
  17. ramona300

    ramona300 True Classic

    Second run of the day and half a second better to the esses. This is from the first run
     

    Attached Files:

  18. ramona300

    ramona300 True Classic

    This is my first run of the day on the 22nd of July, siting run before I bent the car! 36.32 seconds. A 127 with a heavily modified 1050 engines best time was 36.54.
     
    NM850 and Chaostoy like this.
  19. ramona300

    ramona300 True Classic

    Had a bit of a win a few days ago. Finally got my tacho to work with the Ford coil pack. The stock tacho operates from the negative off the single coil. The Ford coil pack is 4 coils in pairs. I could get the tacho to run half speed by using one side of the coil pack. When using the circuit diagram that ties both sides together I would get nothing! By adding a 10k resistor to the line going to the tacho to ground it works perfectly. The Jaeger tacho is notoriously difficult to work off multiple coils but a 40 cent resistor saves the day.
     

    Attached Files:

    kmead likes this.
  20. ramona300

    ramona300 True Classic

    This is a video from a couple of weeks ago I posted on Facebook but it might be of interest to some here. The front fuel pump for the front mounted tank failed and the car stopped when the swirl tank ran dry! Plenty of crook gear changes and that sweeping left hander was never handled correctly.
     
    kmead likes this.

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