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I ended up ordering the stage 3 turbo from BNR as they no longer machine the exhaust housing to make a stage 4. I paid the $100 core charge to save on shipping down there. I'd rather give it to him than FedEx. So this means I get to keep my old turbo so maybe in the future I'll see what I can do about sourcing the parts to do my own upgrade. Pretty soon I'll have enough spare parts to build another airplane. As they say "ignorance is bliss", and I was content to think I was not asking much of my turbo and so I didn't have to worry about it, but again this list has proven its value as random info not even directed at me has made me aware that at any given time my poor little turbo could give up the ghost and leave me looking for a place to put down where there are none. I asked him to put a 7psi spring in the actuator, as the TurboSmart controller will allow me to achieve more at the touch of a button. But I may just replace it with my own actuator anyways. I'll decide when I receive it. Now I'm going to rethink my intercooler installation. I had recently removed it as I didn't feel it was a very effective installation due to space constraints and didn't think it was really doing much for me. I now think it was doing more than I thought, but I now have an opportunity with some space freed up to do a better install. Last year I bought a little bitty tiny lithium battery to replace the big old lead acid battery. As it has some smarts on it, the first thing it told me was that it didn't like being over on the hot side of the engine, behind the turbo. So since it is so small and light, it was an easy thing to move over to the other side of the engine, right beside my primary alternator. So I removed the Vans battery mount and now have quite a bit of free space in which to mount the intercooler, however it will probably require some modification. This is all yet to be determined....
Hi Dave; Another question for you about your wastegate. Are you using the wastegate that he provided? And what pressure is the spring? I told him I would rather use my own wastegate, but he didn't seem to know what I was talking about when I told him it was a piston type rather than a diaphragm and kept insisting that I'd want to use his with a 14psi spring. I also want the lowest possible spring pressure as I have a TurboSmart electronic boost controller which can give higher pre-programed pressures at the touch of a button, by venting the boost pressure signal to the actuator. But it can't give any pressure lower than what the spring pressure is. One of my considerations for lower max boost pressure is that my engine was not originally turbocharged so I have the high compression 9.4:1 rotors. Fot that reason I've always been conservative and tried to limit my boost to 6psi, which is my current spring pressure. When my original diaphragm actuator burst, I saw about 16 psi without detonation, and it was fun, but not something I want to subject the engine to regularly.
Thanks, Todd
Hi Dave; I talked with BNR today and I'm not sure he really got what I was looking for as he started by saying that a "stage 3" is what I should have then said probably a "stage 1" would be good for me. But other than that I did like what he has to offer. However I'm thinking that even though I don't feel that I have the demands that you do, if I'm going to go this far, I'm going all the way and might as well go for the "stage 4". The "stage 4" involves machining the exhaust housing to make room for a larger turbine wheel while the others don't. So I wonder if I could source those other items and do this myself. But as I don't even know enough about my starting point it's not very realistic to find the finish line without a significant investment in time. So for the low price of $1amu, I can have more than what I need. I'm also convinced that paying the $0.1amu core charge is good value when you have to deal with international shipping. So I guess I just need someone to give me a little shove to push me over the edge and call him back with my visa#. If he had an "add to cart" button on his website I think we'd be past this point after a few beers watching playoff hockey.
Todd (The only thing stranger than watching hockey in August, is that there is less fans than my beer league games)
Todd, Thanks for that as was exactly what I was thinking. Have tried many workshops in OZ and either ignorant or don’t want the job. Freight listed to the US and back can be $300 each way. Makes the $100 cheap. Will contact them, and see what eventuates as way down the path of fitting the stock turbo, really do not want to start again. Done that too many times before. Thanks, Neil. Hi Neil; I talked to BNR today on the phone about my needs and wants. He said it was about a 3 week turnaround time on the turbo, so I said maybe later this fall. So he suggested that for a $100 dollar core charge, he could just get one there and modify it for me and I can keep this one. That's kinda a no-brainer, because it would cost me that much to ship mine down to him. Then I'm only paying shipping one way. So for you that would make even more sense.
Dave and all, Finally great advice that I cannot get anywhere else as mention “Aircraft” and the phone line goes dead. The oil cut off is great as well for I have personal experience with a turbo failure in a truck – you would not believe the amount of oil that can fit into an exhaust! That took more time to clean than replacing the turbo-- all 5 gallons of it. Will see what I can source here in OZ as to a turbo , as the freight both ways to the US is murderous. Happy with the mod cost which will be $1300 Oz dollars. Still a cheap turbo. Freight I am guessing will be another $300 at least. Neil. Hi Dave; What did you use for a shut-off valve for your oil? Kelly, you are right. I even mentioned the TO4-E50 in my post above. Mark, its not about the horsepower so much as keeping the turbo in its proper operating environment for the conditions you are going to be giving. You mentioned "300-400hp" in your post, but it seem that perhaps you dont have a specific target in mind. Thats fine, but you are not going to land much above 180hp unless you have a specific target and a plan to achieve it. The stock hitachi you mention is a T3 turbine. It and the 2nd gen 13b it ran with were only rated at 200hp in the car - and only for short bursts. I did what you are thinking about doing. I ran the stock turbo to see what I would get. I was making a little over 200hp and the turbo lasted for about 70 flight hours. Looking at its turbo map, the impeller was running over 100k RPM. It's very surprising it lasted 70 hours. It probably only lasted that long because most of the time I was not running full power. The turbo imploded on my first long cross country. I was almost home and decided to let it loose a little. I was running about 30" MAP at 17.5k altitude. It lasted about 30 min doing that. My advice, if you want to experiment with turbos, is to install a shut-off valve on the oil feed line to the turbo. I now have one in my installation. When the turbo goes it will be hemorrhaging oil into the exhaust. Without a shut-off valve, you will run out of oil before you can get very far. With the valve, you can continue to fly n/a as long as you need. Play around with that spreadsheet I sent you. Make up numbers that are realistic for how much boost at what altitude you realistically want to fly, then find a turbo to fit those parameters. You can cut and paste various turbo maps onto the spreadsheet. They are available on the internet but most of the relevant ones are there on the spreadsheet. Try to keep the turbo in its center island of efficiency while staying away from the 'surge' line. Also, keep the RPM under 60k if possible. You will find that Kellys suggestion of the TO4-E50 is a good choice and readily available. You will also see that the stock T3 does not belong in an aircraft. Group, I have no running experience yet but when I purchased my turbo I settled on a "Turbonetics" TO4-E50 with a 1.15 a/r turbine housing so as to not get into any overspeed problems..........FWIW Dave, Just how much extra Hp do you think you got withy the upgraded Turbo? I will be happy with 250 to 300 HP from the stock Hitachi. Am I off with the fairys having this expectation? Neil. James, I had my stock housing upgraded to TO4 by BNR Supercars. They also have options for the Renisis. http://bnrsupercars.com/ Cost is $950 for the level 4 upgrade. Makes a nice tight fit. I had a big discussion about Turbo maps that you can find in the archives. I settled on a TO4-H or TO4-E50 to top out around 350hp at sea level. Attached is a turbo excel spreadsheet that you can use to evaluate various parameters in selecting a turbo. James, 2 flying that I know of – Todd Bartrim and Dave leonnard. Think they have the standard RX7 Hitachi turbo. Just been around the world trying to get an affordable turbo for my renesis which does not exist if you talk to drag racers etc., Quotes between $4500 and $6500. Bought 2 hitachi turbos for $125 and one looks set to go while the other will need bearings. There was an offer of one in south Africa for freight only. Would be a bargain. Just hooking mine up now, but as usual much to go that I have not factored as usual. Finally found an intercooler that may fit. Best, Neil. Does anyone out there have any recommendations for a turbo (brand and size) for a 13b in an aircraft? 300-400 hp range. Reasons or experience is appreciated! Auto racers have their needs but are different from aircraft... or so I've heard. My 13b's are nearing the decision stage for turbos. Thanks, James Whitehurst
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