What The What is THIS?

[RockJustRock]

I've never driven "by wire". Are they THAT bad?

http://www.pedalcommander.com/?v=7516fd43adaa

[AndyB]

Some are. When they're done right, they're fine. They aren't always done right.

[68scott385]

Having learned to drive in a carbureted vehicle with a mechanical link between my right foot and the carb, I find that drive-by-wire to be a serious threat to my safety. That wasn't a please accelerate now, that was a get-tf-moving demand. More than once have I found myself praying for mercy because the computer I was driving wasn't sure if it could move when I said to. It IS a donor waiting to happen and it will have a mechanical throttle linkage.

[irsa76]

Alot of the times the issues with DBW is more to do with emissions regulations, ie suddenly opening the throttle with a mechanical linkage usually results in overfuelling until the airflow catches up which throws the emissions out the window. This is especially noticable on diesels, my car literally noses over if you snap the throttle open where as if you roll into the throttle it's fine.

[Monster]

I've never driven "by wire". Are they THAT bad?

Me no likey ...

[DanStokes]

My Dodge/Cummins is more or less drive by wire but the only hesitation I get is waiting a couple of seconds for the heat to build so the turbo can get busy. But mine IS an early version (no aftertreatment) so maybe it gets worse in the newer ones.

EDIT: The HHR is full-on drive by wire and is fine. It is, of course, a grocery getter but fills that slot perfectly, one of the best all-around general transportation vehicles (as opposed to a performance car) I've ever been around.

Dan

[RockJustRock]

So how does this box look?

[AndyB]

A fair number of motorcycles are fully drive-by-wire these days. It's used in that application for smoothing power delivery, and works pretty well; it also allows for low-power modes (i.e., for racing in the rain). In some cases it's being used to skip the complexity of having secondary throttleblades, which are mostly there to ape the older constant-velocity carbs. Works great in that application.

In a budget econobox, it's going to be made by the lowest bidder, and tuned conservatively, so that the makers can advertise better MPG figures. Hell, my GTI has no connection between pedal and intake, and it works fine. Like I said, just depends on the quality of the system and what it got tuned for... it's a little like when you see cars advertised with ABS or traction control--some systems are really stellar and work incredibly well (F1, Ferrari, etc), and some systems are clearly the cheapest crap they could get to meet whatever regulation required it (see also ABS on mid-90's Beretta's--which was openly dangerous, imo).

That box, if it works like the others I've seen, simply makes the throttle output more closely match the input. If you plant your foot rapidly, the output goes up at the same pace, instead of spread out over a half-second like the factory intended.

[RockJustRock]

Of course I'm just stirring the pot here. I'd never have a vacuum secondary carb as a kid. When stuck with an air door one first thing I'd be tweaking the accelerator pump full squirt then loosening up the air door. Loved my double pumpers and the 50cc kits. Destroyed a LOT of mufflers, just too much gas. Wish I could get back to this. Dr. Frankenstein a few EFIs and build a few motors with the Double Dumpers. Was SO much fun letting others drive my junk and FEEL the power.

Makes me wonder if this box messes with tip in enrichment of drive by wire? How far can you go reprogramming stock EFI? Aftermarket EFI? Can you emulate the old "Stick car ONLY three barrel, never pop the clutch below four or five grand"? Note the quad accelerator pump nozzles and the 1:1 ratio..... BuhWhaaaaa!

[RockJustRock]

That carb there is why Holley HAD to make the Dominator series.

[AndyB]

I'm used to engines with a rather broader RPM range than a typical V8.... If you have flatsides on a bike and snap the throttle WOT under a certain RPM, you'll just kill it dead. Not enough air velocity through the carbs means no vacuum in the venturi, means no fuel flow. THONK, dead. Most EFI systems that I've played with have an accelerator pump type setting, with DBW or a proper cable connecting the driver to the butterflies. It mostly depends on if you've got a proper tuning suite for the ECU that lets you change ALL the settings and screw everything up, or if you've got something that gives like two settings and nothing you want. Kinda a get what you pay for sorta thing. There's always the megasquirt option, if you want ALL of the control, ALL the time!

*My last proper car had a vacuum secondary on it, and I actually set it up to open slower, not faster. Wheelspin is great, but being in front of the other guy is greater.

[RockJustRock]

Before EFI I wanted to build an Accel. pump carb for Harleys. Also an intake with a large plenum. The carb tech and powerband tuning the bike manufacturers, particularly Honda it seems to me is SO far ahead of the car people. A small bike motor that can pull hard from 2,500 to waaay over 10K seems incredible in light of the power OUTPUT at peak. SMH.

I once tried to be a bike guy, just not a Liter Bike guy.

In cars a small bog FEELS faster than no bog, until you REALLY feel no bog.

I wasn't a stall speed guy either. Idle and slap.