Dual throttle bodies
After consulting with designers at a couple of OEMs, it seems like it will be overly difficult to connect them electronically. I will be tapping into the original shaft and connecting through linkages. I will post some pics when done.
why not piggy back off the electronic 90mm throttle body, drill and tap the shaft on it. machine a new shaft for a regular non electronic 90mm throttle body that has threads and a stop (or a locknut for final adjustment) on the one end of it so that it threads into the shaft on the electronic tb?
Could you simply use one DBW and one cable style. Make the shaft on the DBW unit attach to the cable unit. That would be much easier than attempting to connect two DBW units. Either way you go about this tuning is going to be addressed right away be someone who knows what they are doing.
Just put a single plane on it and throw an Accufab 4150 4 BBL throttle body on it.
If you do add another TB the tuning for DBW is going to be daunting. "The throttle just opened 10% but we are getting a ton more air------dump fuel!!!"
I think if you can convert it to cable it would be light years better. And if you can convert it to cable, read my first sentence.
If you do add another TB the tuning for DBW is going to be daunting. "The throttle just opened 10% but we are getting a ton more air------dump fuel!!!"
I think if you can convert it to cable it would be light years better. And if you can convert it to cable, read my first sentence.
^ If it is going in a vette good luck fitting a 4150 on top of a single plane. I agree the tuning issues will be very daunting, but there are ways around it. All it will take is some time, enginuity, and lot so patience.
Do you need twin Throttles? How about an oval.
Harrop made this one off for Sams performance on a HTV2300 with electronic throttle.
http://www.youtube.com/watch?v=suAEuPEzjZ8
Harrop made this one off for Sams performance on a HTV2300 with electronic throttle.
http://www.youtube.com/watch?v=suAEuPEzjZ8
This is something similar to what I plan to do. Although the shafts arent aligned so the second TB will go through some linkages. I removed the 90mm DBT shaft cap and drilling and tapping a M6 thread to add an extension.
Unfortunately it wont work. The electronic signal uses feedback from the throttle position sensors to determine where the butterfly is. e.g. a 4V input to one drive-by-wire (DBW) motor may yield 80% open, and on another DBW motor it could be 75%. This is due to manufacturing tolerances.
Also, splitting the signal will result in twice the current draw through the computer and it doesnt like this...
The only way I see that it can be done (electronically) is to make an integrated circuit with programming to develop a signal to a second DBW motor based on inputs from the 1st DBW throttle position sensors. Then have error checking between the two throttle position sensors and set a max deviation (e.g. 5%).
Also, splitting the signal will result in twice the current draw through the computer and it doesnt like this...
The only way I see that it can be done (electronically) is to make an integrated circuit with programming to develop a signal to a second DBW motor based on inputs from the 1st DBW throttle position sensors. Then have error checking between the two throttle position sensors and set a max deviation (e.g. 5%).
I would remove the motor from the DBW and control it like normal. Have the motor actuate a cable which in turn runs two mechanical TB's.
You would have to fabricate a gear or something that bolts to the motor to attach the cable.
Or has this already been suggested?
You would have to fabricate a gear or something that bolts to the motor to attach the cable.
Or has this already been suggested?
why not use a single shaft with the motor in between?
Why not run one mechanical TB with a mechanical pedal, and then use the sensor from a DBW pedal as the TPS on that TB, and use all GM electronics to drive the second electronic throttle? Then the only tuning you'd have to do is make sure the opening area on the "tps sensor" from the first TB equates to the same commanded opening on the second TB...now all your normal error checking still works like it's intended to and the computer shouldn't even know.
The only other thing then...if you're going to have 2 independant plenums your idle control and map sensor will be new issues...so I'd make a common plenum, or a means of connecting 2 almost seperate plenums...then you can just use the DBW idle control and the mechanical TB won't be associated with it.
...you'd also want to make sure the sensor from the DBW pedal is ok under the hood rather than inside the passenger compartment...OR just leave the sensor on the DBW pedal, and adapt a small linkage to the same pedal, to pull the cable for the manual TB...and have no sensors on the manual TB...a TPS on the pedal or on the cable driven TB is really doing the same job anyways, as long as the cable doesn't get stuck, break, or fall off
...and if you wanted to use cruise control, you'd then do a manual cruise cable style box actuating the PEDAL rather than actuating the TB...kinda like how on an F-Body with traction control, the cruise actuates the traction control via cable, and that actuates the tb via another cable.
The only other thing then...if you're going to have 2 independant plenums your idle control and map sensor will be new issues...so I'd make a common plenum, or a means of connecting 2 almost seperate plenums...then you can just use the DBW idle control and the mechanical TB won't be associated with it.
...you'd also want to make sure the sensor from the DBW pedal is ok under the hood rather than inside the passenger compartment...OR just leave the sensor on the DBW pedal, and adapt a small linkage to the same pedal, to pull the cable for the manual TB...and have no sensors on the manual TB...a TPS on the pedal or on the cable driven TB is really doing the same job anyways, as long as the cable doesn't get stuck, break, or fall off
...and if you wanted to use cruise control, you'd then do a manual cruise cable style box actuating the PEDAL rather than actuating the TB...kinda like how on an F-Body with traction control, the cruise actuates the traction control via cable, and that actuates the tb via another cable.
Last edited by Mike454SS; Apr 21, 2010 at 03:36 PM.
If its the twin plenum concept you are really aiming for why not fit a larger or custom large throttle body and design a y-piece tube to fit the TB to the plenums.....just a thought?
Beings as you seem to be aiming for N/A results i think this would work and improve the torque and power dramatically....
Just thoughts of course:yup:
Cheers,
Andy.
PS. you know if you need a test mule im around still mate....Loved the carbon fibre and we have never been able to get remotely close to the power my ute was looking at putting out with that prototype you were working on
Beings as you seem to be aiming for N/A results i think this would work and improve the torque and power dramatically....
Just thoughts of course:yup:
Cheers,
Andy.
PS. you know if you need a test mule im around still mate....Loved the carbon fibre and we have never been able to get remotely close to the power my ute was looking at putting out with that prototype you were working on
Have talked to him and his system looks promising. However, he is a while off having something that is plug-and-play. In the meantime, I will play with some linkages to run a slave TB from the DBW TB.




