EFI conversion on a Gen-1

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Impressive work, well done.

Unless I've missed it I would be interested to know what difference it has made to torque, power and fuel consumption.

Without any major rework of the intake and exhaust, the power will be similar to carbs. Fuel consumption whilst cruising with some stop and go traffic is about 44MPG. 49MPG is doable on 64 mph. I do run Sean`s overdrive venture transmission kit so that also helps.
 
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As mentioned, it might be worth investigating using EFI with the stock carbs. To do that, I designed the first iteration of the new manifolds. Since the wall thickness has to be much thicker for 3d printed pieces compared to the original aluminium ones, I cannot use the originial boots/rubbers, the outer diameter is just too big. So it`s going to be slip-on as you see here. The final manifolds will be printed with carbon/nylon again which has some elasticity. Hopfefully can tighten them up some more with the original clamps even though it`s already a nice tight fit. Below is the first print, which needs about 5mm extra height as you can see:

IMG_9268.jpg

The injector is located on the inside. I don't think it`s ideal to have it on the side but due to lack of space it`s the only option right now. If anyone has some smart ideas about that let me know :)
IMG_9266.jpg

As always, to be continued.
 
As mentioned, it might be worth investigating using EFI with the stock carbs. To do that, I designed the first iteration of the new manifolds. Since the wall thickness has to be much thicker for 3d printed pieces compared to the original aluminium ones, I cannot use the originial boots/rubbers, the outer diameter is just too big. So it`s going to be slip-on as you see here. The final manifolds will be printed with carbon/nylon again which has some elasticity. Hopfefully can tighten them up some more with the original clamps even though it`s already a nice tight fit. Below is the first print, which needs about 5mm extra height as you can see:

View attachment 95988

The injector is located on the inside. I don't think it`s ideal to have it on the side but due to lack of space it`s the only option right now. If anyone has some smart ideas about that let me know :)
View attachment 95989

As always, to be continued.
you could try putting a recess on the inside, so you could put a thin Oring for a better seal.
 
I have to say this is one of, if not, the most impressive modification threads I seen anywhere. So very well done.

I have most of the skills to do this but have no enthusiasm to even start.

Anyways, been meaning to post this a while back, a friend of mine mentioned that there are companies that do 3D metal printing. The way I remember it is that metal is mixed with a filler so once printed, the piece is heated so the filler melts and the metal fuses together. (obviously the printed part is made slightly larger than the final piece bigger due material loss)

I would expect an inlet made that way would end up with thinner walls and be more heat resistant, possibly stronger too.

He said the cost was not prohibitive so it may be something for you to investigate.

Re. Injectors, there may be smaller ones than the ones you are using that would allow better placement.... I sure you've looked already.
 
I have to say this is one of, if not, the most impressive modification threads I seen anywhere. So very well done.

I have most of the skills to do this but have no enthusiasm to even start.

Anyways, been meaning to post this a while back, a friend of mine mentioned that there are companies that do 3D metal printing. The way I remember it is that metal is mixed with a filler so once printed, the piece is heated so the filler melts and the metal fuses together. (obviously the printed part is made slightly larger than the final piece bigger due material loss)

I would expect an inlet made that way would end up with thinner walls and be more heat resistant, possibly stronger too.

He said the cost was not prohibitive so it may be something for you to investigate.

Re. Injectors, there may be smaller ones than the ones you are using that would allow better placement.... I sure you've looked already.
Thanks for the compliment! Much appreciated!

Yes, this is just for prototyping, if in the end it will be a commercial product it has to be metal (printed or CNC). If 3D metal printing provies a strong result with the right cost, that will be the way to go.

For now, heat is not an issue. I`ve used my soldering iron on the carbon/nylon ones and nothing happens till about 200 degrees celcius. Since it`s inlet side and the head is watercooled, the inlet never goes above 100 degrees.

Indeed it`s hard to find smaller injectors that still has have enough flow. There might be moped ones that are smaller but they are not usable. So far, no options there. Some more investigating required but I doubt it would really make difference if they are injecting from the side.
 
As I need to reinstall the Vboost (connected to the Ignitech), does anyone know where to get the Vboost connector that is normally part of the Vboost controller? It seems to be a very specific part and I`d prefer to reuse the original than having to put a new connector on the Vboost servo. Thanks!
 
Thank you, but with shipment to the Netherlands and import duties that`s 120 dollars for that connector:D. I`d hope to find just the connector but indeed it`s no longer findable.

I’ll bet Sean has a bucket full of them.
I just ordered four new intake rubbers from him for the airbox since I cut up my others to make the throttle bodies fit. If I`d known I was missing this one I would have asked then.

Perhaps I`ll just buy make connectors like these and 3d print the connector housing:
https://www.ebay.com/itm/255127557233

Keeps me busy :)
 
Time for an update pic:

1735847152754.png

It took me a bit to print the manifolds so the carbs slip on perfectly. Also making the fuel rails was a bit of back-and-forth. Above is the system as it is now whilst I`m doing a 24-hour leak test. The fuel regulator keeps the lines pressurized so if it`s good after 24 hours, I call that a success.

Never mind the fuel lines, they will be redone later. They will both go directly to the left, so they are routed underneath the carbs. That way the carbs can be removed without having to fiddle with the fuel lines.

Next step is the carbs which will be turned into throttle bodies. I`ll remove the floats and float needles as they will bounce and break without any fuel. I`m not sure yet what to do with the sliders. Do they also have a dampening effect when you quickly open the throttle? If so, I`ll keep them. If not, I`ll print some dummy sliders that don't move. Let me know what would be the best option. Thanks!
 
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Depending on how and where you plan to inject the fuel at low RPM and partial load I wouldn't think you need the sliders. Their purpose is to maintain high vacuum in those large bore carbs at low RPM for fuel delivery to the airflow at idle and atomization at varying load, RPM and throttle conditions. Your pressurized fuel and fuel mapping should address the low RPM, vacuum and varying conditions, right ?

VERY impressive work there, that's quite a project you've taken on ! Mapping that system with V boost should be interesting.
 
Depending on how and where you plan to inject the fuel at low RPM and partial load I wouldn't think you need the sliders. Their purpose is to maintain high vacuum in those large bore carbs at low RPM for fuel delivery to the airflow at idle and atomization at varying load, RPM and throttle conditions. Your pressurized fuel and fuel mapping should address the low RPM, vacuum and varying conditions, right ?

VERY impressive work there, that's quite a project you've taken on ! Mapping that system with V boost should be interesting.
The OE throat diameter of the carbs is insufficient to supply sufficient charge at higher r.p.m.'s and this demand is satisfied via the second carb.
If OE carbs are used for the throttle bodies (without V Boost?) will they be able to meet the demand at higher engine speeds?
Alternatively, if they are bored out how will this affect low speed running?
 
Depending on how and where you plan to inject the fuel at low RPM and partial load I wouldn't think you need the sliders. Their purpose is to maintain high vacuum in those large bore carbs at low RPM for fuel delivery to the airflow at idle and atomization at varying load, RPM and throttle conditions. Your pressurized fuel and fuel mapping should address the low RPM, vacuum and varying conditions, right ?

VERY impressive work there, that's quite a project you've taken on ! Mapping that system with V boost should be interesting.
The EFI system indeed manages RPM (crank angle), MAP, TPS, coolant temp and intake air temp to get the correct fuel load. So it will work just fine. It`s what you say regarding maintaining high vacuum that is important. If that could add some 'smoothness' when opening the throttle it might be a good plan to keep them. So I`m not entirely sure what to do there.

And thanks for the compliment!
 
The OE throat diameter of the carbs is insufficient to supply sufficient charge at higher r.p.m.'s and this demand is satisfied via the second carb.
If OE carbs are used for the throttle bodies (without V Boost?) will they be able to meet the demand at higher engine speeds?
Alternatively, if they are bored out how will this affect low speed running?
I will keep the Vboost, if not it would have the same power as a stock Vmax without Vboost.

It`s all about intake speed. Smaller intakes make for more torque, which is always nice on a V4-1200cc motorcycle :). But as you say the smaller bore cannot let enough air (and fuel) through to get the max horsepower. Vboost is the best of both worlds by adding the additional fuel via the second manifold. Let`s see how it behaves with EFI.
 
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