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Why don't these exist yet? I searched quite a few years ago and gave up and looked at Fast Manifolds but am trying again to my surprise to find nothing still. I've searched high and low but all I can find is two setups of custom examples. Has everybody running a carb style manifold had to convert over to cable throttle? I just find it really strange.
For anyone confused, this but with an electric on the motor on the side...
I don't think there is any demand for this because DBW sucks.
In all seriousness, I don't personally know anyone who prefers DBW, other than the few who have a setup with tight engine bay packaging or some other situation that makes a cable very difficult to fit. Most who use this type of manifold wouldn't have any fitment problems running the cable, so there is little reason not to.
Granted, with proper tuning DBW can be *almost* as responsive as the cable, but never superior IMO. So I think the demand just isn't there.
DBW works great with aftermarket EFI systems... I know with Holley EFI you can make a DBW throttle move faster than your foot is capable of controlling.
Whilst not the prettiest...I've seen people cut up a DBW body and adapt it to push/pull on a linkage to operate multiple bodies or a different manual body.
And if you are using a factory computer, you're going to need to use the respective DBW unit that ecu is expecting.
They don't exist because there is no demand. There is no demand because there are plenty of options out there already that work great. You can get an elbow adapter to run a dbw throttle body on a carb intake. You can run dbw throttle bodies on stock and after market intakes. You can run a carb on a carb intake.
There wouldn't be in money in making a 4 barrel dbw because there isn't a need for them in the market. So nobody gonna make them.
If anything I think the demand is higher for DBC. In my opinion the feel of DBW sucks compared to DBC. I want to be in full control of it.
I know with Holley EFI you can make a DBW throttle move faster than your foot is capable of controlling.
In a practical application though, it's still a two step process. Your foot gives input, then a signal must be sent. No matter how fast that signal is, I don't see how adding a second process (the signal, aka "a middle man") could be faster than a one step process that happens instantaneously with the movement of your foot.
Originally Posted by 00pooterSS
If anything I think the demand is higher for DBC. In my opinion the feel of DBW sucks compared to DBC. I want to be in full control of it.
In a practical application though, it's still a two step process. Your foot gives input, then a signal must be sent. No matter how fast that signal is, I don't see how adding a second process (the signal, aka "a middle man") could be faster than a one step process that happens instantaneously with the movement of your foot.
I agree.
In reality, the foot/cable/linkage etc can be fairly slow, even if you think it is fast though. And DBW gives you the opportunity to move the blade differently relative to your foot, but of course that depends on what the ecu allows you to do.
When people say it can move faster than your foot...that is absolutely true...and if the ecu for example seen the pedal starting to open fast...you could tell the blade to open faster to achieve WOT, predicting what the user intends to do. But again....it depends on the complexity of the control system
It seems a lot just have the blade mirror the pedal, which almost makes it pointless as you arent using the system to make use of the flexibility it can offer.
But when setup correctly, there is no way a driver should be able to tell any difference whatsoever between DBW and DBC in terms of response, because the systems are much much faster than any human will ever notice. But not all control systems are equal.
If people think it's slow etc....you'll certainly never see a cable etc on a F1 car, and few engines will be as responsive as those, although that would be at the very upper end.
I'm sure in time though, someone will make a DBW 4 barrel setup, because it will become more popular. Although how compact etc it might be is another matter of people want to retain a more classic visual on things.
When people say it can move faster than your foot...that is absolutely true...and if the ecu for example seen the pedal starting to open fast...you could tell the blade to open faster to achieve WOT, predicting what the user intends to do. But again....it depends on the complexity of the control system
This still leaves a disconnect between the foot and the blade, moving the blade in "predicted" ways rather than actual foot input (which is the only way that it could truly react faster than a direct connection). At that point, results might not be 100% consistent or as desired, depending on the complexity and/or tuneability of the system I suppose.
Most of the OE setups I've driven leave me less than impressed. Some of them get much better with tuning, but still not as good as a cable IMO. I can't say that I've ever driven one that was an entirely aftermarket system though, perhaps they are better.
This still leaves a disconnect between the foot and the blade, moving the blade in "predicted" ways rather than actual foot input (which is the only way that it could truly react faster than a direct connection). At that point, results might not be 100% consistent or as desired, depending on the complexity and/or tuneability of the system I suppose.
Most of the OE setups I've driven leave me less than impressed. Some of them get much better with tuning, but still not as good as a cable IMO. I can't say that I've ever driven one that was an entirely aftermarket system though, perhaps they are better.
The issue most have with OEM setups...is OEM do it differently than you might expect.
Often there is a torque demand table which relates to pedal movements...which then translates to another table for blade movements. Simply because WOT doesnt always produce the most power/torque at every rpm. In some case a smaller opening might produce more, so you go WOT and the ecu should target blade position that does actually give best power/torque. Of course that may not always feel like the driver expects, and likewise with say low-medium pedal openings, they might decide to dampen blade movements or reduce them to soften how the engine responds.
So it's no a case of DBW being less capable, it's just how they have set it up probably not doing what you might want it to....but how many of those setups you've driven have been proper performance ones ? vs a crappy daily driver type affair ?
And why performance cars, say like M3, M5, Ferrari etc would offer the driver various settings, from comfort, normal, sport modes etc which will change not only gearbox shift strategies, but also how the engine/throttle responds to the driver input.
But again....the blade can move faster than your foot in most cases, so any perceived delays in most cases...are probably in your head or simply down to it being programmed to behave that way. Although yes I'm sure there are some crap blade motors out there too, but most will be very strong, and one thing is for sure...I'd never want to stick my finger in to test how powerful they are ! lol
IMO, DBW is a good thing as it can open up a lot of easy options.
Sort of back on topic as to how to create say a 4 barrell....a little googling shows what BMW did with their M5 and ITB's which for most part are mechanical, but with a remote DBW motor unit.
This thread has some good photos
Obviously you'd need an aftermarket ecu to give you the flexibility to use any DBW motor though
Or here is where someone has taken a DBW unit, cut it in half and removed the blade, but then attached a linkage to the shaft so he can then actuate a pair of mechanical blades. A viable approach if stuck with the factory ecu, so as still to use parts it would expect fitted. Although you'd still need to be able to adjust any control strategies to suit the new setup.
Traction control and skid control that really do their jobs, need DBW..
In theory you could have a launch box (Intercepting the pedal) you'd hold the pedal to the floor, the launch box would watch for the transbrake/Brake release and open to max traction under traction control,, (Launch control anybody?? LOL) Kinda already out there.. But an aftermarket version would b cool..
Traction control and skid control that really do their jobs, need DBW..
In theory you could have a launch box (Intercepting the pedal) you'd hold the pedal to the floor, the launch box would watch for the transbrake/Brake release and open to max traction under traction control,, (Launch control anybody?? LOL) Kinda already out there.. But an aftermarket version would b cool..
Launch control, traction control ( throttle is very slow there though ), flat shift, anti-lag, idle control, cruise control....all manner of things become easier and more flexible with DBW.
But traction control does not need DBW, although it is one control option.
But yes for launch control you can easily have foot on the floor and blade at a lower setting for either a time delay, speed delay, distance and ramp it up thereafter...really, just depends on what your control system offers you.
it's not new, it's out there on decent standalone ecu's
Not sure I'd entrust such things to some sort of interceptor box hooked onto a stock ecu though as it would be easy to create risky conflicts.
So it's no a case of DBW being less capable, it's just how they have set it up probably not doing what you might want it to....but how many of those setups you've driven have been proper performance ones ? vs a crappy daily driver type affair ?
Various Corvettes would be the highest level I can recall driving. I did drive a well-tuned C5 a couple years ago that made me nearly forget it was DBW, but it's still not quite the same IMO.
Originally Posted by stevieturbo
But again....the blade can move faster than your foot in most cases,
The blade perhaps, but the actual reception of signal at the TB can't be quicker with an indirect connection. Now, that's not to say that a fast moving DBW motor wouldn't be capable of opening the blade faster than one can possibly move their foot, it certainly could, but signal reception will always be slower with a two step process (i.e. the signal can't be sent any sooner than your foot moves the pedal, unless we're talking about those anticipated/predicted/scaled movements - which is still only going to be as good as the setup and, unlike a traditional cable, might not provide results which are always desired in every type of driving situation/condition).
DBW on an aftermarket efi system like my Holley efi allows you change the opening rate on a sloping scale. That could be helpful if you need to pedal the car you could program a stepped curve so when the pedal is 100% the throttle is 100% but you could set it so when the pedal is 95% throttle is 80% (or what ever you program)allowing you to react faster. It would work on the other end of the scale also, If you have a large throttle body and need less throttle opening early you can dial it in.
Think of it as a infinitely adjustable linkage. If set correctly could make you more consistent.
Various Corvettes would be the highest level I can recall driving. I did drive a well-tuned C5 a couple years ago that made me nearly forget it was DBW, but it's still not quite the same IMO.
The blade perhaps, but the actual reception of signal at the TB can't be quicker with an indirect connection. Now, that's not to say that a fast moving DBW motor wouldn't be capable of opening the blade faster than one can possibly move their foot, it certainly could, but signal reception will always be slower with a two step process (i.e. the signal can't be sent any sooner than your foot moves the pedal, unless we're talking about those anticipated/predicted/scaled movements - which is still only going to be as good as the setup and, unlike a traditional cable, might not provide results which are always desired in every type of driving situation/condition).
True, but when those signals are thousands per second.....it really is a moot point and beyond human perception. It'd be a bit like saying you can feel every single combustion event. Or...you can see the flickering of a TV screen that interlaces at around only 50 times a second.
The reality is we cannot.
Now there may be "feel" issues with regards to pedal and a normal linkage/cable/spring etc, but then again all cars are different there anyway. Some will have light pedals, heavy, some with variable linkages etc all to try and do what DBW can easily do.
Even the actual LS2/3 DBW units inlet tract is shaped to reduce airflow over the lower openings so even with a fully controllable blade they've felt the need to create a mechanical restrictor for airflow if you like. No doubt to make low rpm/load driving more smooth, more easily etc All of which can allow alrger units to support more power up top, without any negatives down low.
I only changed to DBW last year myself, and I can see or feel no negatives whatsoever. But there are a lot of flexibility options with control. So only positives for me.
Although I'm not using a factory ecu
Either way, we have choices....that is always good.
Hate the DBW system on my C6. Much prefer a cable TB. A lot of the issue is technically the tune and not just because it is DBW so I will of course go that route first, but I can see why there is not a market for DBW 4bl TB's.
Most of the people going to that setup care more about pure performance than the ease of use/any drivability benefits of DBW (auto blip, anti lag, etc).
In reality though, surely the only reason one would want a 4 barrel setup on the motor is for appearances ? as it to retain a more classic look.
There wouldnt be any performance advantage for such a setup vs a more modern setup either with a single blade or multiple blades, ie ITB's ?
I can think of other reasons that could "possibly" make them perform better and or be more user friendly over a single blade style throttle body.
Height... Some of these are only as tall as needed for throttle blade clearance, So with 4 small blades rather than one large you have a much shorter throttle body.
Allows standard type air filter or low profile blow through hat that can be positioned any direction needed like off of the side or at an angle in relation to the engine.
Progressive linkage.... Flow the same air or more with more precise metering.
Strength... It's harder to bend 4-small throttle blades under heavy boost than one large one.
Air distribution? Probably not much of an issue with a dry intake but you end up with the same flow over a larger area.
Flow in general, You can run a dual 4-barrel throttle bodies that would flow a ton and have all the linkages/filters and so that are already available for dual carb application.
Again I don't know if there would be an advantage in air distribution in a dry intake but having 8 small throttle blades over the a wider area sounds better in my mind lol.
I know there are some intakes that are made specifically for dual quad setups that are low/standard profile all the way up to tunnel ram style that would be better suited to them.
It seems that those of us who dislike this system are basing our opinion on OE applications (even higher end ones, such as Corvette). Tuning certainly helps, but there still seems to be a delay/general disconnect that is in fact noticeable (and undesirable) to some of us. I don't know if this can ever be totally perfected within the limitations of aftermarket tuning on an OEM PCM.
Again, admittedly, I've never experienced an entirely aftermarket DBW system/controller. It makes sense that these would be much more user friendly with greater tuning flexibility/capability. But, as I'm happy with the cable setup on my 4bbl, I don't see any reason to consider the costs and complexities of such a change.
07-13-2017, 01:09 AM
Drive By Wire 4 Barrel Bodies 
