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t70

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  1. Well Mike, You are partially correct. However, what you are referring to is the issues of the "skin effect" and surface tension of fuel against the port walls. This effect is present when you actually polish the intake. I use 60 grit sanding discs, which are universally accepted as the correct maximum polish level. The reason you don't want it to be polished is that there needs to be a small amount of turbulence at the surface in order for the fuel not to collect against the walls of the port. Now, that all being said.. did I need to port them.. no. However, the turbulence created within the highly inefficient intake plenum itself, will likely result in enough turbulence in the air to keep fuel properly atomized. The port work will likely only just increase the velocity near the valve so that low end response is slightly increased. Now.. the real issue is in porting the exhaust.. that should be thoroughly polished. However, once again we have a problem. The log-type manifold is highly inefficient and the exhaust porting and polishing won't likely result in any real noticeable increase in flow. Port Matching the exhaust will likely help a bit and will reduce hot spots on the exhaust side. Hi Alex. The Billet Pistons and Carillo rods were about to $6000 my cost. The crank shells will be upgraded with the same shells I used in the last build (the racing shells that Mike Sekinger used to sell). As for the blue and red hose connections.. They have been running on the previous car for 3 years and have never had even a hint of a problem. Including a 3 days straight on the dyno.. However, I will definitely keep my eye on them. This entire system, as some of you may remember, has been tried, tested, tortured and tuned on the dyno before. As some of you may recall, I hit over 450 Wheel torque on the dyno (which maxed it out.. and we had to wait for the system to cool down to restart) on full stock internals (minus bearings) and stock turbos. We dialed it back to 430 wheel torque and 430 wheel horsepower to ensure the longevity of the engine. I should add that those numbers were acquired with an ambient temperature of 37 degrees Celsius and the Intake Air Temperature on the dyno.. fully heat soaked, never exceeded 52 degrees Celsius. The system is extremely effective. The original project on Aerobats car was a 4 year event that resulted in one of the nuttiest cars I have ever driven. I have actually re-done a lot of the standalone mapping so that it will be substantially more daily driveable. Previously.. it was soo bloody torque that it was actually hard to accelerate without spinning up both rears (295 wide tires and a quaiffe LSD) in first and second (anything over 1/3 throttle was tire smoke) and 3rd would spin up as well at any temperature under 20 degrees Celsius. What I've actually done to the mapping is relate the boost level targets to throttle position. So, Unless you actually put it to the floor, you won't get full high boost. And.. as a little extra added protection, I have related the boost pressure to wheel slip %.. This will result in a basic form of traction control and make it so that I can pleasurably drive the car without constantly trying to regulate horsepower with my right foot. Here's a quick video of the first build on Aerobat's car:
  2. I may have my Pistons available soon.. They are forged, with only about 2000 miles on them. How soon are you in need of said pistons?
  3. Well.. Christmas has come and gone.. However, I didn't remain totally stagnant. Here's a few things I did in the last while.. I did some mild port work to the intake runners and intake ports.. here's a pic. I also installed the entire water section of the intercooler plumbing: Also, I cleaned some exhaust pipes.. before and after I also decided to do a clean installation of my wide-band control modules. It's kind of hard to see what's going on in this picture, but this is behind the right hand seat.. I have cut-away the insulation in order to fit the two wideband controllers to a nearly flush mounted appearance. Here's the first shot, showing what is behind the carpet: and this mildly blurry picture is the carpet pulled back over everything.
  4. The idle air control motor has been an issue I have contended with multiple times. The idle control motor opens when you are under full boost to give the engine as much air as possible. Then, it can stick wide open. The problem went away for me after cleaning the motor and letting the car run from cold to 3 hot fan cycles without touching the throttle.. then I let it cool to about 70 degrees and fired it up again, it stumbled for a bit, then did a idle up to 1800rpm and back down to 850 and the problem was solved. As for the Secondary injectors.. They are not operated the way they are stated in the manual at all. They come on at about 3500rpm under load. At this point, the primary injectors actually reduce their duty cycle to compensate for the secondary injectors injecting large amounts of extra fuel. If you disconnect your secondary injectors, you will lean out under load and likely melt your pistons. I learned this when I put the standalone into Aerobat's car. I had the secondaries still running throught the factory ecu and I was controlling primaries through the standalone. The duty cycle of the injectors at 3500rpm and higher was DRASTICALLY reduced. Once I disconnected the secondaries and re-mapped my fuelling at 3500rpm+, the amount I increased the fuelling was about 15%, which on 750cc injectors is A LOT OF FUEL..
  5. The secondary fuel pump relay also controls your after-cooling system. It operates the electric coolant pump and the fans. So, if it is failing, you need to make sure it's replaced or you will likely have head gasket problems in the near future. Now, I should ask, is the car actually stumbling, or is it hunting for idle? If it's hunting, then I would look to cleaning the idle air control motor as they gum up over time. However, if you have drastic trim differences between banks, you will definitely want to check your cam timing. The lotus V8 is VERY sensitive to cam timing and the car will compensate for it with the o2 sensors up to a point. After a certain amount of the cams being out of timing, the computer will set a lean or rich condition on either bank. The most common cam to slip is the right hand side (UK drivers side) intake cam.. which, awkwardly enough is the cam the engine references for TDC. As for the fuel pump system: I usually replace the factory primary pump with a Walbro pump from a mustang. The primary pump, however, is not usually the problem. It's actually the fuel lines themselves. The fuel lines vulcanize horribly and if you are having the famous "warm start" issue that is almost always blamed on injectors.. it isn't usually the injectors.. its the fuel lines in the tank. Pull your fuel pump "hat" out and replace the rubber lines and the clamps. The factory clamps are junk, you need to replace them with stainless steel screw clamps. The reason the warm start and idle usually have issues is that when the lines leak, the pressure does not remain in the fuel system. So, it takes longer for the fuel system to prime without normal fuel pressure. Let me know how it goes...
  6. If this is true, my engine is fully disassembled at the moment and if it's an upgrade.. I would like to have it before I re-assemble.
  7. Well.. I'm still waiting for the block to be finished.. I think I would have designed and cast a new one faster... Lol.. Anyhow, I have also begun a bit of head work.. I stripped them down today and ported the intake runners. Maybe I will get my block back before Christmas?? Lol
  8. I don't even know what to say.. this is such an awful story. I do have a side note to add though.. you do not need a super expensive clavis gauge. I have been using a guitar tuning app for my iphone for a long time.. and I have compared it to the results of the Clavis Gauge and its within 1-2 hz. There are a couple of things that can go wrong when doing the belts and the engine build though. With the central timing gears (the bottom ones) you MUST MAKE SURE THEY ARE COMPLETELY DRY when you install them and you don't use any type of locktite on the bolt that holds them in place. You also must ensure that the intermediate plate between the two gears is also completely dry and free of grease. If you don't.. you will experience slippage and you will have a total engine failure. Next.. another common mistake is not fully cleaning the Loctite 572 out of the actual camshaft bolt threads. Run a thread chaser through the cams and clean repeatedly with brake cleaner and compressed air and thread chase again. Any oil in the journal is not a good plan. The other precautionary measure is to run the engine up to temperature and then re-check the tension and check the cam gear position with the tolerance pins again. I always triple check the tension and the cam positions.. And.. I have had to re-adjust tensions afterwards. Now.. I have also seen significant slippage on the intake cam on the right (UK drivers side). I don't know why this cam is the most common to slip.. but I have seen up to 1/2 tooth of slippage over time.
  9. Well... I know you all are hoping for a good update.. but at the moment.. there isn't much to say. I am going to use the factory crankshaft (as the cost was way too prohibitive to make a stroker kit). I have, however, gotten custom JE Billet (not forged) pistons and Carillo rods. I also went .012" over on the bore (due to the bore and taper being out of round and true) which will increase displacement from 3.506 litres to 3.531 litres. So, the project will likely start back up this winter, once the engine is finished at the machine shop. Now.. I expect to keep my torque under 500 ft-lbs and just tune up the horsepower a bit at the top end. I don't expect to exceed 630hp with this build as I just don't think it's going to be necessary. The car was already crazy with 430whp and 430whtq.
  10. Gunter.. I will be involved with the engineering process of the stroker idea, however, in terms of how we complete the process... I will be drawing on the experience of my engine builder. I have te utmost faith in his abilities. We will see what we learn as time goes by. As for the solid liner concept.. I like that one a lot. However, I would be moderately concerned with the expansion characteristics of he solid 1 piece liner vs. the aluminum block..
  11. I agree about the rod offset. There would be some serious design/engineering issues to overcome with a slightly bigger stroke. However, once again, quoting mike -- he believed it was possible to do a 4.0 liter stroked and bored n/a engine. I don't believe that a bigger bore is safe though. Having looked at how close the liners are and the gap between each bore inner lining, I just don't think that one would want more than a 10-20 thou increase in bore. Even that, I would want aftermarket liners.
  12. Alright, i will update that post after this post. The basic idea for this season will be just to upgrade to billet pistons. The reason for this decision is that I have to buy all 4 "stroker kits" up front and I simply don't have the funding available at this moment to do that. However, should there be sufficient interest, I will peruse it next season. The hp I am speaking of is more a matter of what might be achievable given proper tuning. When discussing the capabilities of the engine with mike Sekinger, he said that he thought the engine could handle about 700hp on the stock block. This kind of hp number is not likely possible on the factory ECM, unless I am able to hack the software over the next year. My current plan is to achieve 500 ft-lbs of torque and between 600 and 650hp with the stroker kit. Sekinger also believed that the factory crank could only handle about 550hp... Which is the main reason for the stroker kit. If Aerobats esprit (which is up for offers at the moment) had forged or billet pistons and upgraded turbos, we would have put down closer to 550hp on the dyno. However, since he is still running the factory cast pistons, I didn't think it was wise to lean the mixture out just for a "dyno number". I will say, however, that while I was doing some road tuning, I did go about 0.2 afr points leaner than target in one section of the map and it kicked like a donkey. (I did tune it back immediately after though.) So, I know the power is available with billet pistons in place. Aerobats car at the moment, however, feels about as quick... No.. Quicker than a straight-piped Lamborghini diablo 6.0. As for the bearing size, I haven't determined enough of the design yet to say if they will remain the same. It would appear that I am unable to edit my post... Hmm.. Could be an iPhone issue?
  13. Gunter- I will not be using forged pistons in the kit. The expansion behaviors of forged pistons are too drastic for my liking. Billet pistons are stronger than forged pistons and have similar expansion qualities to cast pistons. This means that the pistons won't rock as much in the liner when the engine is cold. So, the kit, should I acquire a large enough number of interested parties, would include a longer stroke forged crank, similar length forged rods and shorter wrist pin to deck height billet pistons. This should result in an engine that can handle upwards of 600-700hp. It would also make the turbos come "on line" a little lower in the rev range and should spoil slightly quicker as well.
  14. Here is a video that briefly details the construction process.. http://youtu.be/k2GGXtN4q1U
  15. Ok, so in order to do the stroker kit, I will need 4 buyers. The price is not quite nailed down yet. I have decided to just to billet pistons this year. However, I think i will be Persuing the idea of the stroker kit next season. That is, unless I can line up 4 buyers this year.. I do expect the price to be about $7000CAD each. The kit would include billet pistons, forged rods and forged pistons. If anybody is truly interested, pm me please.
  16. Well, apparently, all the tuning shops shut down for Xmas, but I should be able to find something to do while I wait for my v8.. Maybe I should do some work to my old 88?? My goodness, would my wife love me if I did that..
  17. @steve: I have begun the process of test fitting a transmission, it will require some very interesting modifications, but I really expect that it can be made into a bolt up kit that would only take about 4 hours to install. My r and d time will likely be 50-70 hours to make it work though. As for the rest of the project.. I will be discussing some more interesting options with the engine builder on Monday/Tuesday. But.. My thinking is a 3.7 liter stroker forged crank.. It does depend on the cost of the crank. I am also considering doing billet pistons instead of forged pistons. The cost will increase, but I am planning to sell everything that I don't need. Hopefully this bottom end doesn't cost more than $5000..
  18. @steve: I have begun the process of test fitting a transmission, it will require some very interesting modifications, but I really expect that it can be made into a bolt up kit that would only take about 4 hours to install. My r and d time will likely be 50-70 hours to make it work though. As for the rest of the project.. I will be discussing some more interesting options with the engine builder on Monday/Tuesday. But.. My thinking is a 3.7 liter stroker forged crank.. It does depend on the cost of the crank. I am also considering doing billet pistons instead of forged pistons. The cost will increase, but I am planning to sell everything that I don't need. Hopefully this bottom end doesn't cost more than $5000..
  19. @ Steve, Yes, it is the car from Manitoba that you are thinking of. How's the Maserati? @ Gunter, let me know how you progress with the information from JE. As for the rest of the build, it's going to be just the motor this year, but next year --- mmmmmm, I can't wait!
  20. I cannot believe that I didn't even think to look in the manual.. WOW.. Thanks Gunter!
  21. Ok.. so Mike Sekinger said it was forged.. it weighs like a forged crank, it looks like a cast crank... Has anybody gotten an actual solid answer on this?
  22. well.. The Harrier isn't from "oil money" in this case. The owner owns a jet engine repair company as i recall. As for the garage thing.. It really sucks, but, I have since taken a raise and a management position at work (which the garage had previously prevented me from being able to do.) The end result is being able to afford the v8. Thanks Patrick!
  23. WOW!!! DO I LOVE THIS IDEA!!! I was floored when I was assembling Aerobat's engine and I realized how the system worked. I couldn't grasp how this could be done this way without any kind of keyway. I will be doing this on my engine for sure.
  24. Thanks Gunter, These pistons are 8.5:1 compression as opposed to the factory 8:1. I will be having something different built as well, so I can probably offer those for sale in the future too. as for the IAC valve.. I could tear it apart... should be fun.. but it is pressed together with pinch points to hold it as such. As for the part number on the IAC -- 0 280 140 516 is the part number..
  25. Alright.. the piston part number is: E0306-918HP.. hope that helps!
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