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Everything posted by Arttu

  1. Ok, let's take a closer look on that. "Boost is only measure of restriction" Well, sort of true. Boost pressure is result of air flow produced by the turbo and restriction of caused by engine. But while it's true it isn't actually telling anything, just stating the obvious. Also it's true that the air mass flow is what dictates the power that the engine can produce. But the catch is that you can't increase the air flow indefinitely without adding pressure. The engine shifts roughly its displacement of air volume at every cycle. Sure you can improve that by tuning cams, ports and so on, but even at the best case you will hit the limit somewhere around 110% of displacement. So if you want more air mass flow through the engine you have to increase the pressure. And the engine doesn't care how the pressure at intake has been generated. It just gasps in that volume of air at given pressure. So it doesn't really matter if the turbo producing the air pressure is capable of flowing 300cfm or 600cfm or whatever. As long as the engine demand doesn't exceed capacity of the turbo. Ok, in reality size of the turbo has some effect on the air flow. A bigger turbo MAY have better efficiency at required pressure / flow point which then results lower intake air temp exhaust back pressure. And those help to get more air flow through the engine at the same boost pressure. But even that can get you only so far. Eventually you just have to increase the pressure to get more flow and power.
  2. Here goes a pair of very common opposite statements or beliefs: Boost equals power - more boost always means more power. Boost is only measure of restriction - air flow is what makes the power and these have no connection to boost pressure. While both have good amount of thruth in them they are usually used as overly simplified statements which makes them quite misleading.
  3. That's some bad luck with that plug! Did you get any power readings before it let go? What kind springs you have in the clutch? You may still need quite stiff springs to make the clutch hold at lower rpms where the boost starts to come in. I guess you know it will be quite challenging to get consistent launches with that kind lock-up clutch?
  4. I think this depends heavily on your turbo setup. If you have an efficient setup that has low exhaust back pressure, 1:1 with boost or lower, then the cams probably work pretty much like on NA engine. But if the exhaust pressure is high then short duration / overlap cams might give better results. As far as I know blowing fresh mixture through during overlap isn't usually a problem. When you are at operating rpm range for the cams there isn't enough time for that. But pushing the exhaust gases back to inlet can be a real problem if the exhaust pressure is significantly higher than boost.
  5. Like @johnrsaid there are some differences but overall they are very similar and required mods should be fairly small. For that swap you probably need to open up the crankcase mouths for cylinder sleeves and use a 1100 output shaft bearing. That's all what I can recall from top of my head.
  6. As far as I know biggest risk for the clutch are "energy conserving" additives used in modern car oils. Bike oils shouldn't have these. So if you just stay away from synthetic car oils you should be on quite safe ground.
  7. Personally I haven't noticed any problems with fully synthetic bike oils. Regarding the temps. I think for oil 80-100°C is pretty much ideal operating range and below 120°C is still ok. If you are constantly getting over that I would start getting worried. For short periods even higher temps shouldn't be a big problem. I haven't checked much the engine surface temperatures but the cylinder block seems to follow oil temp quite closely. I assume that exhaust side of the head will get significantly hotter. But in any case the engine at normal running temp is too hot to touch.
  8. Well, a turbo is probably one of most cost effective ways to tune these Yes, it costs quite a lot money to fit one but $$$/hp will be hard to beat. For low cost tuning options I guess the first one is fitting some good exhaust, maybe more free flowing air filter and tuning the carbs to suit. No idea how big improvements these will give on an EFE but I guess it should be something noticeable. Beyond that it starts to get expensive. Bigger pistons with big block, head porting with bigger valves, hotter cams, bigger carbs and so on. At some point the bottom end start to need attention too if you want it to be reliable. Clutch basket needs reinforcement pretty soon although this is more like a maintenance job since it will get loose at some point even with stock engine. Crank rebuild is highly recommended if you want to rev it higher or get big power otherwise. That's fairly expensive specialist job and the specialists are rare these days.
  9. Yep, wastegate routing can be tricky with big and efficient turbos. And having well flowing exhaust manifold makes it even harder. But I think it's also very important in your case. Most likely you need to be able to control boost accurately down to 7 psi range to get good consistent launches. One good option is place the wastegate exit on the turbine housing. That seems to work very well usually.
  10. So making 20 psi on 10 psi spring without boost controller adding more? Then there is something to fix for you if you want it going down the track in controlled manner
  11. Brakes are black magic, you never know if they get better or worse when you touch them. Ok, that was just joking but actually my experiences are somewhat like that. So I would just bolt on the calipers that you have and see if they work properly. If not, then it's time to start thinking alternative options.
  12. It should go straight in, no differences in mounting points between 1100e and 1150efe.
  13. Good progress! But what this actually means? Dyno was reading 108 but wheel speed should have been 151? Was the wheel speed measured by a sensor or calculated from engine rpm? If from rpm it can be either clutch or tire slipping, if measured from wheel then it must be tire slip.
  14. It should work just fine. At least I know plenty of people using air shifter or foot shifting with quick shifter on carb turbo bikes. If it is working correctly it shouldn't cause any backfiring on intake side. One key thing is to avoid too long kill time. Typically 50-70ms should work fine with air shifter.
  15. Looks quite ok, I think. Just few notes: If you want to start safe I would take out a couple of degrees from 140kPa and above. I would ramp up timing with rpm a bit slower. 2000rpm column around 20° and 1500rpm around 15°. Although I haven't done much experimenting with this area, this is just how it seems to be on stock timing curves. As extra trick you can try to stabilize idle with timing: Move the lowest column just below the idle rpm, like 900rpm. Set the next column at your target idle rpm. Add few degrees on the lowest column. This way the timing advances if the rpm drops below your idle target and that tends to drive rpm back up.
  16. Oil cooled engines that I have tuned have usually liked about 28-30° timing at 1 bar boost. And if the stock N/A timing is around 34-36° then that would be close to degree per 20kPa that you mentioned. 1 degree per psi sounds excessive in any case.
  17. That's quite subjective question and the same goes with any modification that we do on these old bikes. So only you can answer if it's worth of it for you.
  18. There isn't anything especially expensive but plenty of stuff that adds up. Some examples for a low end system from top of my head: ECU - 300-600€ Throttle body set with injectors - 100-200€ Fuel pump - 100€ Pressure regulator 50-100€ Sensors - 50-100€ Wideband lambda sensor - 200€ Bunch of small items that you can't even think about before startting - 100-200€ Like said it's possible to get many of these for cheaper too if you have some luck or patience for searching. On the other hand it can get much more expensive if you have any special requirements.
  19. It can naturally vary a lot depending on what kind system you want, what parts you use and where you source them. But as a ball park figure I would say 1000-2000€. Lower end of the range is pretty tight, means some very low cost ECU and using plenty of used parts, but should be doable. You can make it even cheaper if that's your main goal but that will mean compromises here and there and it will be more difficult.
  20. Forced Induction Performance Tuning by A. Graham Bell.
  21. Seems that I don't have notes about my current pistons. But previous 77mm Wisecos were 216g + 75g for the pin. Any ways, I think 10.000 should be ok for you too. Yep, always better to be cautious than throw a rod out of the cases... But like said, I think 10.000 should be pretty safe if you have properly made crank.
  22. If I recall correctly a stock GSX1100 doesn't have a limiter, but I might be wrong. However, I have been using 10.000 as a limit on my turbo GSX, currently 1327cc. And I think that should be pretty safe choice. To get some perspective I think pro stock GSX engines run up to 13.000 and they are around 1700cc, longer stroke and BIG pistons. But lifetime of the crank isn't very long on those.
  23. You might want to check @Blower1project threads. He has an EFE with a M62 blower. Different bike but you might still get some ideas. I was thinking a bit about your routing plan for the chargers. But looks like feeding the blower by the turbos is pretty much only option with those parts. The M62 can't shift enough air for 400hp from ambient pressure so you have to feed it by pressurized air. Also you probably will need around 2 bar boost to reach over 400hp which is quite much for the K04 turbos if you want to keep them at good efficiency range. So sequential charging makes sense, sort of Just remember to fit an intercooler somewhere too...
  24. Yep, there are some practical reasons why most of the drag bikes look the same nowadays...
  25. Looking good! Although I think it would have been even more cool with some RF style fairings
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