Single throttle body

[Cncbusa]

Anyone running this on big hp turbo bikes here? A friend of mine is and the bike is a monster. Lots of talk about it among drag guys that i know and im helping design a intake for one. Curious who else is doing/done it. Dont really need that "crisp throttle response" on a 6-700hp wideopen throttle drag bike.

 

[Cncbusa]

Ill try to get some pics soon.

 

[KZScott]

ive seen a couple funny bikes like that but they were gs based turbo efi, not a busa.

 

[mjl3truck]

Scott Horner was working on one years ago. At teh time he said it was a PITA to get to run cleanly off boost.

 

[Mr Brown]

Most cars only have single throttle body, wonder why it would be hard to adapt one to a bike?

 

[fallenarch]

My BMW K1600 has a single throttle body. The goal here was torque and a precise consistent fuel mixture going to the 6 cylinders (according to BMW of course).

 

[Mr Brown]

My BMW K1600 has a single throttle body. The goal here was torque and a precise consistent fuel mixture going to the 6 cylinders (according to BMW of course)

That's how most cars do it, from small to large.

 

[fallenarch]

That's how most cars do it, from small to large.

Yeah, but those long intake runners aren't exactly going to get you screaming HP.

 

[Mr Brown]

Yeah, but those long intake runners aren't exactly going to get you screaming HP.

No, but they help out under the curve, where most engines spend most of their time. Big (relatively speaking) motors like the Busa or your K aren't gonna rev to the moon, and you don't need to wrong their neck to get em to move. There are tons of n/a and turbo motors (stock and modified) using single throttle bodies, I don't know what the issue would be for a bike. Either adapt an existing one, or reverse engineer your own.

 

[WuzzaCBXRider]

My BMW K1600 has a single throttle body. The goal here was torque and a precise consistent fuel mixture going to the 6 cylinders (according to BMW of course).View attachment 1610549

Guys I know that put a turbo on their CBXs used a big single carb, some, from a Harley. Easier to adjust than six of them.

 

[Mr Brown]

Guys I know that put a turbo on their CBXs used a big single carb, some, from a Harley. Easier to adjust than six of them.

My supercharged Gixxer had a two barrel mikuni.

 

[Boosted Cycle Perf]

I don’t know how I missed this thread. This is something I wanted to try on Lucy.

I figured the same equivalent surface area of the ITBs translated to like a 93mm throttle body. So that’s where I’d start. With a stock ecu the biggest hurdle I’d see is the acceleration enrichment from a larger initial gulp of air in throttle changes. Would be very easy with a standalone.

I think it might be a mute gain. I’d imagine the biggest gains would be from having the ability to change the runner lengths. Although keeping the injectors in the stock location wouldn’t allow for much change.

It be a fun experiment.

 

[202mphbusa]

I don’t know how I missed this thread. This is something I wanted to try on Lucy.

I figured the same equivalent surface area of the ITBs translated to like a 93mm throttle body. So that’s where I’d start. With a stock ecu the biggest hurdle I’d see is the acceleration enrichment from a larger initial gulp of air in throttle changes. Would be very easy with a standalone.

I think it might be a mute gain. I’d imagine the biggest gains would be from having the ability to change the runner lengths. Although keeping the injectors in the stock location wouldn’t allow for much change.

It be a fun experiment.

Have you any experience with Megasquirt? If you decide to try a single throttle bodie I would be willing to send mine for you to experiment with.

 

[Boosted Cycle Perf]

Have you any experience with Megasquirt? If you decide to try a single throttle bodie I would be willing to send mine for you to experiment with.

Yes I do.

I think a stock ecu will be up to the task for testing purposes. It would be cool to use a gm tps. And the pipe dream would be to get the factory ecu to play nice with a gm IAC.

 

[Cncbusa]

Heres a really niccce example

 

[Cncbusa]

Not as nice but effective

 

[airborneuph]

Eric at DAS had a single throttle body on his turbocharged GSX R 11 a long time ago. When I asked him about it he mentioned that the throttle response wasn't very good. If I can remember correctly he used a single TB off a mid sized GM 6 cylinder car. I don't remember how he got one injector to provide the amount of fuel required though. And yes, it didn't idle very well..

 

[rubbersidedown]

I have dummed it down in my mind to the fact that one supply of fuel/air mixture can't deliver the exact supply needed the further it gets from 1 big supply. In an inline 4 config for instance would the 2 middle cylinders not receive a greater amount of f/a mixture than the outer 2 cylinders. Even with a huge amount of boost is it not near impossible to equalize all cylinders?
It this part of the issue?
Flames welcome.
Rubb.

 

[202mphbusa]

I think Das has gone back to a single throttle bodie on the supercharged bike
or he tried it using IAS circuit to control entry air volume to try and limit to a lower boost level

 

[Cncbusa]

1 injector shower per cylinder. Im comfused as to the fuel supply concerns?