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I was chatting with my friend about converting the drive by wire system to traditional throttle cable. He mentioned something along the lines of one made for a mustang. My question is what, if you guys know would be involved with still allowing the ECU read the pulses given by the angle or distance of the GO pedal, and/or whether or not the conversion has been attempted.
 

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  • individual tb for each cylinder head. Linking them together cheaper.
  • individual tb for each cylinder
  • some people prefer the cable. :dunno:
  • some EMS only work with cable
  • cable is better than satellite
 

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Its possible, but a standalone is most likely needed. It will also send the factory computer into limp mode unless you relocate the TPS signals (may not matter if you use a standalone).

One way to set it up is to install two tps sensors for the factory ECU. One 0-5V the other 5-0V and maintain the Pedal Position Sensor. Then another sensor for the standalone. Again this may not be needed because of the standalone, but its one way to do it while maintaining the facotry ECU. The biggest issue is going to be keeping the PPS and TPS aligned properly in regards to votage offsets.
 

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  • individual tb for each cylinder head. Linking them together cheaper.
  • individual tb for each cylinder
  • some people prefer the cable. :dunno:
  • some EMS only work with cable
  • cable is better than satellite
HAHAHA :rolf2: cable is better than satellite....thats a good one illz!
 

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a cable gives instant throttle response....no lag, no wating for a computer (even though it may be fast, its not direct control by the pedal). It is also thought that stupid new computers limit WOT and will not actually create a WOT situation from a direct stop.
 

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I haven't heard of anyone trying to change it either.

Why would you want to get rid of the drive by wire?
This might be why.

QUOTE(PeterLawson)
I can tell you all that there is a specific reason why your Zeds feel like they run out of steam in the top end. In the program Nissan closes the butterfly in the high rev range, limiting power. We're not exactly sure why they would do this, but logic suggest it is to encourage drivers to change gear earlier and prolong engine life -- meaning less problems in warranty.
With a cable operated throttle, that's not going to happen. And, as others have said, a direct mechanical connection will have a more direct response and granularity of control than a digital interface. Its like driving a car designd to have no power steering, and no power assisted brakes. The response and feel you get is so much finer.

The same can be said with cars with carbies. When they are set up properly for the environment the throttle response is better than an equivalent EFI engine.
 

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Lag is still a biggy though. Pay attention to the tachometer midshift and you'll notice the needle jump up a bit even though your foot is off the accelerator. A mechanical setup would go a long way if you need precise throttle control.
 

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Yeah, I've noticed that the car flares the revs when you dip the clutch.

I also noticed that, after installing my lightweight flywheel, it does it a lot less.
 

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To convert from drive-by-wire to a cable-and-pulley actuated throttle will require the use of an aftermarket ECU. The stock ECU/ECM does not have the capacity to read data from a standard TPS (throttle position sensor).

There are several benefits to the drive-by-wire system that have been overlooked by many in the community. Drive-by-wire can produce a very linear throttle response. Also drive-by-wire has the capacity to produce response times that are far quicker than what is possible with direct cable actuation (though admittedly this is not always the case). Many die hard 1/4 miles racers convert from cable style linkages to rod-style linkages to reduce the lag associated with cable linkages. Though rod style linkages come with their own assortment of headaches.

It is often noted that many drive-by-wire systems do not open the throttle body to 100% at WOT. This is done for good reason. On the typical butterfly-type valve maximum flow rate is usually achieved somewhere around 95% open, not 100%. So there is actually no reason to open the TB all of the way. Typically the stops on a mechanical linkage are set to a similar setting.

For a mildly street-tuned Z, there is no valid reason to make the conversion. However if the power curve has been modified significantly from the OEM configuration, then the mod may produce worthwhile results.

Regards,
Ronin Z
 

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Taking off your throttle by wire will also make it impossible to run TCS / VDC, since our cars close the butterfly to kill torque from the powertrain, not a fuel / spark cut.

For those of us that like driving with it on (weirdos) this may also stop you.


I find that the Z's throttle response is great, to be honest. I don't have an issue with it at all. The only thing I don't like is when the ECU decides to close the throttle butterfly too much in high RPMs, strangling the engine's power output.
 

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Some of the JDM tuners are converting to the throttle cable setups. They claim they have done this becuase they know how to tune better using that style of system, not that it is a better way. They typically use the HKS FCON VPro in conjunction with the drive by cable system.
 

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I haven't heard of anyone trying to change it either.

Why would you want to get rid of the drive by wire?
I was just reading Road and Track Magazine online and came across this in their long-term test section in reference to the Civic Si and 350z's drive-by-wire throttle system:

"Editors all agree that the Si is fun to drive but requires patience, as it takes time for the VTEC to kick in. We've also noticed that revs are slow to drop when lifting off the gas, so much so it hinders the ability to shift up smoothly. This is likely ECU programming of the electronic throttle to help with emissions; our long-term Nissan 350Z had the same tendency. Also, the steeply raked A-pillars block the driver's field of vision more than conventional upright pillars would. We complain about this on exotic cars too. The electronically assisted steering is quick and light-maybe too light."

I have the exact same problem with shifting in my 350z. I shift very quickly and the revs just do not drop fast enough. I know a ligther flywheel will help with this, but I would rather just have the throttle respond immediately. I also read that electronic throttles can react within 50ms, which is so fast that you would not be able to differentiate between a cable vs. electronic system. It's just that the ECU gets a final say in throttle position. (I'm trying to dig up the article I read this from)

Here is the R&T article:
http://www.roadandtrack.com/article.asp?se...article_id=4195
 

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Even on a throttle-by-cable setup, a lighter flywheel will improve the response. So its not exactly a replacement for the other.

I'm running a JUN flywheel, and I love the response it gets. The revs flare less when I hit the clutch, and the engine revs up a lot more quickly (which is something that a cable conversion won't do for you).

But yes, I wouldn't mind having my ECU changed to take out that "slack" from the ECU. Its great for emissions and driving the car smoothly when using low throttle openings and long shift change times, but I didn't buy my sports car to do that.
 

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We are working on the concept of converting to a throttle cable for the VQ install into our S14 chassis. The only issue that we can think of at this time is that the VQ uses the throttle as the IAC and that would be removed causing the idle to be set fairly high. We are tearing the motor down for a build and will worry about it at a later date when it comes time to choose an intake manifolds setup.

The biggest advantage would be to be able to use an over sized throttle body for the higher HP applications. We haven't decided which TB to use since our goal will be more for throttle response.
 
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