Fuel injected twin turbo 79 project

Hey, what projects are you planning or preparing for? CBX, other motos, workshop, WHATEVAH!
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Bob Buehler
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Re: Fuel injected twin turbo 79 project

Post by Bob Buehler »

That is something I will have to check. Unfortunately the problem occurs at lower rpms between idle and 3k. Above 3 k it disappears. Initially the problem was very pronounced and decreased significantly when I added fuel from "Bank #4" injectors. Bank 4 is just a seventh larger injector on the intake manifold. It appears to be the only fuel add on that is used. They system does not appear to monitor a MAP sensor that we could tell and the fuel map only goes up to 107%. Apparently a system that monitors manifold pressure will have fuel map values that go up to something like 170%. We concluded that the only fuel add on is from this seventh injector and it was actually giving "30%" when the motor was at 0 load and increased to 50% at about 50% load. It was or is also controlled by RPM and comes on at 100% above something line 5000 rpms. We took off the 30% down low and that is how we got it lean enough to start but it stumbled terribly. I added it back on and it improved significantly. This lead me to my initial assumption that the fuel was causing the stumble. I have now changed the fuel levels in a enough ways to conclude that I cannot get rid of the problem entirely by adjusting the fuel flow. Now that I'm writing this it sounds like a fuel issue doesn't it. LOL. Well yesterday I was moving some wires around while it was idling and I thought is smoothed out some. I took it down the road and it ran perfectly for a few minutes. So that is what is going through my head today about it.

So the GL1500 of yours looks great. Can you seen any of the system with the bike going down the road. Have you ever put it on a dyno. I saw a kit for sale for the old four cylinder bikes many years ago. Is this one of them or did you pull this together all on your own. Do you have any photos of it all together. I have occasionally given thought to doing something to the Venture but then I think about what is going on under that plastic and I quickly dismiss the idea. The V4s like the V65 that Honda made are so tightly packed together and complicated that you really hope you never have to get in there to do anything. Thank god the Venture has never needed anything. I had a V65 and it was a real pain in the ass to work on. Getting the carbs on and off was impossible and almost everything else was way more work than anything on a CBX

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Gearheadgregg
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Re: Fuel injected twin turbo 79 project

Post by Gearheadgregg »

many many hrs of Dyno time on the SC GL1500, with a sniffer for AFR , it was a knight mare to get the flatspot out of midrange , it was real lean on the first pulls , i have had to ream the main Jet to 265 largest from Sudco was 245, Slow jet is larger, fuel discharge nozzle pump is enlarged. and richest needle on richest setting, also on step richer needle Jet took away my flatspot finally , i run a very Aggressive lead on my timing that is controlled and countered by a Hobbs manifold pressure switch that retards advance @ 1 lb of boost 4 degrees, or by Micro switch from Nitrous instantly, I have all my wires Soldered at end butts also, Yes i do all my own work , but your bike i would be needing help with the FI also, Owner of Magnacharger Bill Bushing is a friend and was on the phone with him many times with this unit he developed..but 13 years now and 30 thousand miles with Blower and has 100.000 mile warranty for Magnacharger ..been a dream to ride and piss off a lot of Busa's that are not serious when hammered. your bike is awesome ! enjoying you sharing your build ! keep us posted when you find the bug http://www.youtube.com/watch?v=gMe0U8iV_tM

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Bob Buehler
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Re: Fuel injected twin turbo 79 project

Post by Bob Buehler »

Gearheadgregg wrote:the only contact info i have is his E-mail (kozmic@fcol.com) Jeff Kozlowski
I tried to email this address but it got bounced back. I got the web page and it looks like the same email address. Are you sure of this address or do you have a phone number. At this point I have no problems with calling on someone with one of these computers.

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Gearheadgregg
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Re: Fuel injected twin turbo 79 project

Post by Gearheadgregg »

Bob Buehler wrote:
Gearheadgregg wrote:the only contact info i have is his E-mail (kozmic@fcol.com) Jeff Kozlowski
I tried to email this address but it got bounced back. I got the web page and it looks like the same email address. Are you sure of this address or do you have a phone number. At this point I have no problems with calling on someone with one of these computers.
well i use to chat with Jeff on the VRCC forum all the time 10 years ago, but lost touch after i left that forum several years ago, that is the only E-mail i have of him wish i could give you more info that's all i had

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Bob Buehler
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Video of test ride posted on youtube

Post by Bob Buehler »

https://www.youtube.com/watch?feature=p ... aZigMwRr0U
if this link works let me know. I just shot some video with my cell phone today and posted it on utube if anyone is interested. if the link does not work just type in twin turbo and it should come up.


steve murdoch icoa #5322
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Re: Fuel injected twin turbo 79 project

Post by steve murdoch icoa #5322 »

Thanks for putting that up, Bob.
A little wavy in spots and i have a sore neck from looking sideways for the last bit. haha.
Is the pop-off valve a boost limiter. What will you set it at once the motor is broken in?
Is lag lessened when using 2 smaller turbos?

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Re: Fuel injected twin turbo 79 project

Post by NobleHops »

Touched that post just to embed the video. Holy smokes, the bike sounds positively evil and you are making great strides.

Great work Bob!
Nils Menten
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Bob Buehler
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Re: Fuel injected twin turbo 79 project

Post by Bob Buehler »

steve murdoch icoa #5322 wrote:Thanks for putting that up, Bob.
A little wavy in spots and i have a sore neck from looking sideways for the last bit. haha.
Is the pop-off valve a boost limiter. What will you set it at once the motor is broken in?
Is lag lessened when using 2 smaller turbos?
I would have edited the video before posting but my computer is in for repairs. I spent all weekend trying to fix it and finally had to give up on it today. The pop off valve is controlled by an actual air line from the manifold. Old style but apparently still used. It has a valve on it so I guess I can set it based on the fuel. I'm running aviation fuel right now since it is available. Its 100 octane. I have only ridden one other turbo and it did not build boost like this. I really think there is something to having the turbos located so close to the exhaust ports. You cannot do that very easily with one large one. I have not seen anyone accept the other twin turbo with the turbo located up front. I would have to ask the other turbo owners for there experience with there rides. When you think about sizing turbos, you are really looking at a turbo running off about 560 cc. They are bridged but basically instead of one large turbo you have two small ones and the advantage really seems to be the ability to place them right up next to the exhaust ports. These turbos are the same ones used on the Suzuki 850? turbo. IHI is the manufacture. I spoke with a guy years ago at a business the sold turbo parts and was intimately familiar with all the factory turbo bikes. He said they all used proprietary turbos designed for their bike accept Suzuki. I think that is why RB Racing picked these for his kit. The turbos and the pop off valve are the only items from that kit that I am still using. Based on Suzuki bike these turbos probably are probably sized for an 850 cc motor so they should be over sized for my application but you would not know that from what I am seeing. This thing seems to be making boost when cruising at 4000 rpms. There is a valve on the intake manifold that might be letting the bike draw through it off boost according to one email I have from the guy that built the system. I thought is was a second blow off valve to drop intake pressure when it opens the exhaust valve. I really don't know. I am going to investigate what is going on a little closer since the AEM gauge is not reading the same as the cheep gauge plumbed directly to one of the turbos. The AEM gauge is tied into the line coming off the intake manifold. That line runs to the adjusting valve that feeds back to the main pop off valve and the CPU. I have not figured out what the CPU is doing with the data yet. As far as I can see it may not be doing anything to the fuel or ignition MAP.

All I can say is that this thing has one hell of a throttle response from 6O mph in 5th gear. I cannot wait to see what a dyno readout will look like. I really doubt it will be over 200 hp since that seems really high. My biggest problem right now besides the hard starting is the transmission. I really think I am going to have it under cut since it seems to be poping in and out of gear a lot. Oh well, live and learn.

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Bob Buehler
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Re: Fuel injected twin turbo 79 project

Post by Bob Buehler »

NobleHops wrote:Touched that post just to embed the video. Holy smokes, the bike sounds positively evil and you are making great strides.

Great work Bob!
thanks for the help I was wondering how to do that since posting photos was complicated enough LOL.

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Re: Fuel injected twin turbo 79 project

Post by Rick Pope »

Bob,

A good rule of thumb is 15# of boost will double your horsepower. So 200 hp might be within reach, but might also bend engine internals.
Rick Pope
Either garage is too small or we have too many bikes. Or Momma's car needs to go outside.

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Re: Fuel injected twin turbo 79 project

Post by Gearheadgregg »

Sounds good ! you hit about 15lbs at one point, put my headphones on to hear it real clear, My supercharged Flat 6 has a bypass valve so while cruising down the hwy @ 75 -90 mph it is in Vacuum mode of 10-15 inch, when throttle is wacked it will boost on demand but normally will have Vacuum @ any cruising speed, funny video had to hide the speedometer due to going a bit over the speed limit, 120-130, and 8-10 lbs of boost, none of this is with Nitrous and really was not hammered full throttle, sound good with headphones on http://www.youtube.com/watch?v=lDNkhbScWRI

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Re: Fuel injected twin turbo 79 project

Post by Syscrush »

This is glorious.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike...
Pics of Perry, my '79.

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