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Comedian last won the day on March 15

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About Comedian

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    RC-F Metal
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  1. I'm just going to leave this here: I was asking about ethanol but they went into Octane just for fun I guess.
  2. Cracked Manifold

    If I'd worn that I might have been warmer!! Sent from my STV100-4 using Tapatalk
  3. Cracked Manifold

    Age can be a huge factor. As time goes by you may start to see a spate of similar failures in due to the properties of the material and welding etc. 10 years operation in the environment of an exhaust header is hard work. Sent from my STV100-4 using Tapatalk
  4. Awesome Sent from my STV100-4 using Tapatalk
  5. Thanks colin Sent from my STV100-4 using Tapatalk
  6. No, I'm saying 13:1 is if the valve was closed (the physical dimensions). The fact it is open probably gives you 10:1 or 9:1 in actual compression. I don't know these numbers are factual - it's an assumption based on the fact your manual says "Use 95"
  7. Imagine the volume of a cylinder. If you compress a 100% of the volume into 10% of the volume you have a compression ratio of 10:1 - that's how the figure is arrived at. However if we have a valve at the top that lets air out for 50% of the piston travel we only compress the second half giving us 5:1 in reality. So the piston does less work and that's how the engine is made more efficient. Less pumping losses. Runs cooler so more thermally efficient. Doing that process just on air in a tube raises the temperature hugely - it's that heat that diesels spray fuel into for ignition. Petrol has an octane rating so it doesn't burn in that heat and it is there while compression is happening. You also don't want it igniting on hot surfaces. So if you have a hot high compression engine you use a higher octane, 13:1 would suggest you need super but the manual says 95 even though the compression figure is higher than an RCF which has to run super. So with higher octane being more resistant it also burns more slowly so your max cylinder pressure comes at a different time. That's where ignition advance comes in. You could potentially actually lose power using 98 over 95. I don't know the valve duration of the Atkinson cycle so can't give exact figures. But if the manual says to use 95 then 98 is potentially a waste of money.
  8. Deposit

    That's the reason my wife gave for wanting an SUV - she just couldn't find one she wanted to pay for until the smaller ones become a year or two older. She's not 70 though so it applies to anyone really. My inlaws also want something more like this but it's out their price range.
  9. This is JUST the attendance poll - and so people can arrange to meet and convoy etc - please see Ratty's topic for all the juicy details and updates:
  10. 2018 RC F

    I sent Davi an interesting CVT with launch gear video and he said it was boring!!!!! I watched it twice for fun. I think we will have to stick to aeroplanes.
  11. 2018 RC F

    I suspect you are correct. Most if not all usually have some smoothing. This is fine as long as both are smoothed in the same way. I though it was odd one was smoothed and one not. But if we use a GSF then the new engine has lost everywhere as I suspected. The dip at 5 looks bad. Be interesting to see if noticeable to the driver.
  12. 2018 RC F

    Colin, could you pm me the numbers please? Sent from my STV100-4 using Tapatalk
  13. 2018 RC F

    Odd. Doesn't make a great deal of sense. Power curve looks reasonable and better than I expected, good midrange, loses over 6000. But as power is a function of torque x rpm / number for nm or lbft , then a wild T curve versus a smooth P curve is hard to comprehend. It's like one is smoothed and one isn't. As dynamometer measure torque and calculates power then if this is official then the power curve has maybe been artificially smoothed (by the look of it). Interesting. Thanks for sharing. Sent from my STV100-4 using Tapatalk
  14. Deposit

    The amount of potholes we have it feels like off road sometimes. I agree with you BTW Sent from my STV100-4 using Tapatalk
  15. F friends

    Daily temptation. That's tough when you think about it! Sent from my STV100-4 using Tapatalk