e-throttle opinions - worth it?

[Matt LJ]

Hey All

I'm building a turbo gen IV LS motor, the base engine runs a 4-bolt 3.5" e-throttle and I have the engine ECU, harness and pedal (don't think I have the 'TAC' module I'd otherwise need to get the GM computer to run it however). 

Anyway, LS is replacing a gen II Chevy V8 (LT1) with a Link G4 (in a Hilux). This setup was running a cable operated throttle body, so cable and pedal are all there to make a mechanical TB work. This seems like the simplest solution other than the $$$ I would need to buy a new cable throttle body and TPS etc. 

So question is, for those who have done/driven both in a performance application, would it be worth trying to get the e throttle working with the G4 or is the extra wiring (and operation of the final product) not worth the ~$350+ to otherwise just buy a new mechanical TB? Id also have to install the pedal which will be a bit of fab work, but prolly similar scale job to making an intake mounted bracket for the cable since there is no provision on the LS. 

Also I'm assuming the G4 is up to the job? It's the silver body version. Thanks in advance 

 

[Davidv]

E-throttle is just awesomely awesomely awesome. 

Firstly - Cruise control 

Secondly - Much easier to set a non linear opening rate to give you more control over the engine

thirdly - Context sensitive pedal control. Make the pedal less sensitive when it's raining, or give the engine less total throttle opening at low rpm, or whatever you need to do to make the car the most drivable in those conditions. 

Heard a really good example about a guy who raced in a series with a breakout laptime. He would tune the max throttle opening down, so that he would drive full throttle each lap and stay just over that time. 

But then if he was in traffic he could switch it off, zing past someone then resume the previous throttle mode. 

In my opinion (for combined road/track car that I use) even just having the cruise control makes it worth while.

EDIT: Using a G4+ though so I'm not sure which of the above things are available on G4.

[neil brown]

G4 ecu can’t do electronic throttle 

[Adamw]

1 hour ago, neil brown said:

G4 ecu can’t do electronic throttle 

The Silver xtreme does in fact have E-throttle built-in. 

Cruise control is not available in the G4, so we can scratch that one off the list.  Another function E-throttle is really nice for is anti-lag but that is not relevant in this case.

So that leaves two main benefits;

1. The multiple target tables like David mentions.  Wet/dry or husband/wife setting etc.
2. The other one David touched on but may not be clear to those who dont know;  Many engines will perform better with a smaller max throttle openings at some RPM's.  For instance you may find at 3000RPM your engine makes more power with 85% throttle than it does with 100%.  With E-throttle you can command a different "WOT" value for different RPM's.

On the flip side, compared to a cable throttle, E-throttle uses up 3 more analog inputs, wiring is a little more complicated, and requires a bit more tuning time.  

[neil brown]

I know Vi-PEC v88 has e throttle and thought was exclusive to Vi-PEC as bigger brother ecu at the time 

[Adamw]

The Silver one was from before Vipec days.  It basically the same hardware as the V88 (E-throttle, P&H inj, internal knock), although it had some software differences also.

[Matt LJ]

Thanks for all the replies guys, thought I had read the silver Extreme could do it. So is the hardware functionally equivalent to the newer implementations (ie will yield as smooth/predictable throttle characteristics compared to the G4+ or oem?). Not so worried about not having cruise control. 

There seems to be plenty of e throttle haters out there based on sluggish response etc, is that merely a product of how the throttle is configured/tuned by the oems or are there genuine compromises that need to be made? At the moment e throttle is sounding pretty good, would be nice to spend the money spent on a cable TB on something else... 

[Davidv]

Yeah mine is really snappy. If you look at the logs of requested throttle angle vs actual, it's very fast. Not instantaneous obviously but its not half a second delay or whatever that OEMs feel like.

In my opinion the OEM mushy pedal is likely for sake of reducing the amount of harsh transient conditions where fuel is least best controlled. For emission / economy reasons. 

[Adamw]

4 hours ago, Matt LJ said:

There seems to be plenty of e throttle haters out there based on sluggish response etc, is that merely a product of how the throttle is configured/tuned by the oems or are there genuine compromises that need to be made?

OEM's need to run as close to lambda 1 as possible under all conditions, so they slow down the transient throttle to make that goal more achievable.  Some of them are terrible, my wife had a company car a few years ago that you could stab the pedal to the floor and back quickly without the RPM even flinching...

Here's a video of an LS7 E-throttle being controlled with a G4 Xtreme, If you watch his pedal you will see it is reasonably responsive. 

https://www.youtube.com/watch?v=uzsRtaXn4L8&t=146s

 

[Matt LJ]

7 minutes ago, Adamw said:

my wife had a company car a few years ago that you could stab the pedal to the floor and back quickly without the RPM even flinching...

 

Haha! You got me laughing with that comment!

 

Will watch that vid a bit later, thanks for that. So is the G4 functionally equivalent to the G4+ for e throttle (other than cruise control aspect)? Also I assume I dont need anything other than the pedal, TB, and loom/connectors (and Link of course)? Cheers

[Adamw]

6 hours ago, Matt LJ said:

So is the G4 functionally equivalent to the G4+ for e throttle (other than cruise control aspect)?

Pretty much, the G4 wasnt quite as flexible with the range of parameters that you could put on the target table axes but all the common options are there.

 

6 hours ago, Matt LJ said:

Also I assume I dont need anything other than the pedal, TB, and loom/connectors (and Link of course)?

Thats about all, A relay will need to be added for the aux 9/10 power.