EFI conversion on a Gen-1

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View attachment 77651

From XB-51 The Best American Plane to Never Fight
Powered by two GE J-47 turbojets under the wings, next-to the wing roots of the 35 degree swept-wing design of 1945, and a third in the rear of the 85 ft fuselage, pretty-extreme for the time. The USA's first three engine light bomber.


A bolt-on swap-in EFI will make a lot of people excited, but their enthusiasm will likely be damped by the cost of entry. Heck, I'm interested in the progress, but when the cost of admission is probably more-than the cost of many individual members of my fleet, it's sticker-shock.

We'll see. Mod monkey crack! Gotta have it!
 
It sure sounds like he's got the knowledge to make it bug-free and functional, the advantage to being able to easily tune for mods is I think an exciting prospect. Let's hope that the research and experimentation results in a reliable, 'do-able' product at a reasonable price-point.
 
Well, to make it a kit, someone needs to take it from here and standardize it. Some bits are easy enough like fuel lines and regulators, some other bits take some more time. The Speeduino itself is no off-the-shelf solution so you might be better off using a MicroSquirt for that. The VFR1200 manifolds need to, like mentioned, be turned around and require all new brackets. This is the most labor intensive part of the build.

And then there`s the return line for the fuel that needs to be added to the tank and the O2 sensor that needs welding into the exhaust.

So for now, it`s no way near a kit but I`d be happy to support anyone that wants to attempt it :).

But back on-topic: I spent a lot of time getting the Speeduino to trigger on the pick-ups to learn in the end that at cranking speed, it doesn't pick up the signal. So I had to use the ignition lead after all.

Got it to run stationary and after a bit of tuning, went for a ride. That in itself was a challenge because at some speeds it bogged down and others it went way rich. But since there is no source for the EFI map, you just have to make it up as you go. The TunerStudio AutoTune comes in there and after driving 10 KM I got something resembling a tune.
Even though the AFR is still all over the place for now, it feels very similar to the carburetors. No backfiring and even got it into the Vboost range and felt the kick!

But enough words just see it go by :)



The Vmax 1200i is born! Happiest person in the world here :D
 
Man this is HUGE! A bung in the header, piece a cake, got one.
Now the manifolds and those pesky linkages, bring it!
High pressure fuel pump and return, can do!
Im sure there's a TPS and other sensors needed.
What Im saying is to have to fabricate some parts to have a type of working F.I. I would give part of a left nut LOL.

The MicroSquirt programming is where the Roadster Cycle engineer/ pilot/
genius Jack Fleming ended the conversation during my attempt at gen1 F.I., so if you would be at all willing to assist a guy along that road it would/could make this a dream come true for me anyway.

Like everyone else here on the forum I applaud and commend you for your knowledge and perseverance in this project.

And yea the bike sounded great in the short clips you've posted.

Thanks
Gent
 
Hi!

Thanks all for the great remarks, much appreciated!

One thing I did over the last week is go from this:
10-jpg.77643


Post0.JPG

So it looks _much_ nicer now. Like almost all the things in this project, I build something and then redo it in a nicer way, trial and error. Must have built around 3 EFI systems by now :).

Besides the quick testdrive I did the day I uploaded the video, I`ve done some additional drives where I collected the logging on my phone. That I ran through megalogviewer (program on the PC) that can parse the logs from the Speeduino and correct the fuel map. The first run looked like this:
AFRRun1.JPG

So the Air-fuel-rate is all over the place. After some optimizing, it looks like this:
AFRRun2.JPG

So that`s already a lot better!

Today, I took the bike out for a 70 KM drive, and it ran almost perfect! Under cruising RPM`s it ran just like the bike with the carbs on. The high-RPM range still needed some tuning but I have the logs now so next run, that will likely also be fine!

Final picture is a nice Dutch one with the bike and some cows :). Pretty much the only thing giving away the conversion is the fuel regulator and the (still shabby) plates around the throttle bodies.

Post1.jpg

I will continue to provide updates but it`s already a very driveable bike. Took it up to 125MPH no worries. Who said EFI couldn't be done? :)
 
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OK, congratulations!

I know many are wanting to have a F.I. system because they don't like messing-around with the downdraft CV carburetors. Even-if it only 'runs as-good as a carbureted system,' that will appeal to many people because they hope that the long-term operation will be for less-maintenance than the OEM system. One of the clues to long operability of the OEM induction, is a clean gas system. That is, a clean, un-rusted gas tank, a clean fuel filter, a good quality of gas, preferably without ethanol, if you can find it, and 'exercise.' Run the bike, don't leave it sit for two months and then expect you're not gonna have issues. Run the bowls dry, and you're probably going to have less issues next-time you ride the bike, assuming you are leaving it sit idle for months.

We all are awaiting your final product, so it can be duplicated by eager VMax owners.
 
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Who said EFI couldn't be done? :)
Not me, as a work colleague use to say, "Anything can be done given enough time and money"

I'm slightly jealous, very well done.

Will you be making a bespoke inlet manifold and vboost delete?
 
Thanks!

For now, I`ll just be driving/tuning/optimizing it however at some stage (maybe this winter) I might play around with bigger manifolds. But that`s another topic :)
 
I am extremely amazed with what you've done. It interests me to see people work out of the BOX. I just read this thread and I'm telling you I don't know how to do half of what you did, BUT I know what you did. My applaud is not as meaningful as what's coming from these guys. But still 'The Ole Cajun from South Texas says 'Un travail bien fait!'......👏👏👏
 
Hi!

Thanks all for the great remarks, much appreciated!

One thing I did over the last week is go from this:
10-jpg.77643


View attachment 78214

So it looks _much_ nicer now. Like almost all the things in this project, I build something and then redo it in a nicer way, trial and error. Must have built around 3 EFI systems by now :).

Besides the quick testdrive I did the day I uploaded the video, I`ve done some additional drives where I collected the logging on my phone. That I ran through megalogviewer (program on the PC) that can parse the logs from the Speeduino and correct the fuel map. The first run looked like this:
View attachment 78216

So the Air-fuel-rate is all over the place. After some optimizing, it looks like this:
View attachment 78215

So that`s already a lot better!

Today, I took the bike out for a 70 KM drive, and it ran almost perfect! Under cruising RPM`s it ran just like the bike with the carbs on. The high-RPM range still needed some tuning but I have the logs now so next run, that will likely also be fine!

Final picture is a nice Dutch one with the bike and some cows :). Pretty much the only thing giving away the conversion is the fuel regulator and the (still shabby) plates around the throttle bodies.

View attachment 78218

I will continue to provide updates but it`s already a very driveable bike. Took it up to 125MPH no worries. Who said EFI couldn't be done? :)
Where did you get the upside down forks stator cover?
 
We all are awaiting your final product, so it can be duplicated by eager VMax owners.

Hi Fire-medic,

Would love to help. Could you elaborate on what you think is required for people to duplicate? Parts list, detailed writeup of all the steps? Something else?

Thanks!
 
Hi Fire-medic,

Would love to help. Could you elaborate on what you think is required for people to duplicate? Parts list, detailed writeup of all the steps? Something else?

Thanks!
Yes, all of that, and the 3D printed parts, or CAD/CAM parts. Anything that you have fabricated, would either have to be in a digital file where someone could use it to get it manufactured, or do it themselves, if they had the appropriate equipment. Some of the items are re-purposed from other bikes, and there probably are sources to obtain used pieces or where to buy them new. Your software if it's available for a reasonable price along with the individual items, and directions/files on what needs to be fabricated, if it all could end-up at a 'bolt-on' installation, plug & play for-instance, would be attractive if the price-point to accomplish the transition was reasonable. To begin, and to get the concept moving, I think a price point below $1,000 would justify enough interest to make it financially feasible. Being able to be easily tuned via a laptop for whatever mods someone puts into the engine would also make it attractive. Common bolt-ons like full exhausts, NOS kits, and more rarely, superchargers and turbochargers, and larger displacement engines, being able to have the induction side easily modified for these, would enhance marketing possibilities. I suspect the largest market is for relatively stock bikes with aftermarket full exhausts. A primary goal would be power and drivability equal to OEM carbureted bikes. That's a big thing to achieve, as the factory has dozens of engineers working in many areas to get that, and this is a '1-man band,' to your credit.
 
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The last I looked a stock carb (new) is over $1,000, so anything above and beyond that one would assume would be priced appropriately higher.
 

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