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Cherisher
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^ good lord man! I've been keeping quiet on this thread because I've been waiting for this... you, sir, are about to change our world!
unfortunately, I won't need this but I'm still stoked to see such ingenuity and effort put towards our car. I hope everyone will appreciate what a benefit this will be!!! most IS owners need this but might not know it yet :lol:
 

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Keep up the good work, that quality and finish looks fantastic!
 

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Cant wait to see finished product
 

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Discussion Starter #45 (Edited)
thanks guys.

I can't wait when its going to be done as well!

I think this idea has been cooking for more then a year! (Probably longer since my interest in throttle body mods can be traced by the replies in some of the threads a few years back)

Samsung s3 AutoGuide app
 

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any update? anxious to see what's next haha
 

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Discussion Starter #47 (Edited)
BAD and GOOD news

So here is the mock setup that I have that should work if I was to go stock intake path with say bigger TB.
The bad news is that to go any other way besides FFIM you would have to change the stock throttle cable, and along with needing a slave TB cable. Of course it would also be required to extended all the wires, was already expected from the start.

The good news is that if I was to go FFIM then I would not have to mess with the OEM throttle cable nor the wires.

I thought about a possibility to grind the OEM round nipple to be a barrel type and use it as slave TB cable, otherwise will need 2 throttle cables.

The issue is that the only reasonable placement of the unit that is not FFIM requires a throttle cable that does a U bend and that requires for it to be much longer. Stock is around 19-20in? I am guessing would need an extra foot or so, probably 35in throttle cable would work. This set up would require some stand off base to hold the unit as seen by my quick dirty cardboard mock up.

As far as brackets go, the OEM side of the CAM I am sticking with the OEM cable bracket, just need an adapter bracket? and then for the slave CAM I will make specific cable bracket.






The OEM bracket will be a little lower, but the hood did close just fine from what I could tell.




Of course if I was going to go FFIM then this unit would simply stay were the OEM TB is and require no rewiring and stock OEM throttle cable will work.
But for now I plan to get the cable brackets and support mounts all designed and machined, once everything fits for a final test fit, I will then go and disconnect the current OEM TB and use it as a test TB slave in DBC, pretty much taking off the sensors and servo motor, and placing a matched throttle CAM


===update===
actually now when I searched ebay, I forgot that a throttle cable with a 90 degree metal bend would work for this and it would probably have to be only 25in long
 

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I haven't read this whole thread but have a few questions. The stock system, as I recall (it has been several years since I last dug into it), reads your mechanical input with a TPS and then the ECU tells the stepping motor to open or close and uses another TPS to monitor when the real TB is open to the correct position which then tells the stepping motor to stop. If I recall, the fuel delivery is linked to this second TPS. Does your system some how fake out the TPS signal somehow so that the ECU doesn't lag the fuel delivery?

I need to go back through that really old thread that I was contributing to, to remember how the stock system actually works.

I am super excited about this project. This laggy DBW makes driving the car on the limit of traction very hard as you can't move the load between the front and rear tires at the instant you need to.

Thanks for your efforts on this Drutort!
 

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If I recall, the fuel delivery is linked to this second TPS. Does your system some how fake out the TPS signal somehow so that the ECU doesn't lag the fuel delivery?

I need to go back through that really old thread that I was contributing to, to remember how the stock system actually works.
This part interests me about the fuelling side, i have had a bit of a search around to find out more and read a little bit on it but didn't read anything definite about which is controlling. If you can please find the one you are thinking of i would be keen to read more on it :bigSmile:
 

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I haven't read this whole thread but have a few questions. The stock system, as I recall (it has been several years since I last dug into it), reads your mechanical input with a TPS and then the ECU tells the stepping motor to open or close and uses another TPS to monitor when the real TB is open to the correct position which then tells the stepping motor to stop. If I recall, the fuel delivery is linked to this second TPS.
That's a pretty accurate statement. To add, the accelerator pedal position sensor and the throttle position sensor have redundant signal monitor signals to watch everything and so ANYTIME the cable is pulled/throttle wheel/APPS is turned, there are 4 signals in different resistance sent to the ecu, 2 from each sensor. The ecu interpretes all signals but mainly VPA and VTA from the TPS and APPS to command the clutch to engage the throttle control motor to clock the butterfly a certain degree based on the critical inputs(engine speed, calc load, ECTS, etc.). The throttle control motor is always running when igniton is on and it's enagaged, it's clutch is engaged/disengaged by the ecu and is what allows the butterfly to move. Running idle the TCM turns the butterfly at 8-20% open. WOT is 64-96% and limp mode or failsafe locks the butterfly at 21% max. I believe our cars was one of the first cars Toyota or Lexus wanted to make it a full hybrid electronic throttle driven but still allowed the cable to open the throttle, which is why the last 30% or so actually engages the gears inside the TB mechanically.

Good luck Drutort and good work!
 

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Discussion Starter #51 (Edited)
The top cable in the pic is the OEM, the last one is an aftermarket one that I used. The cable over all is thin, and doesn't seem like they had the nylon lining inside, which sucks, because with that bend you feel a bit of a jagged if not like grinding/rubbing, if I put it straight or a small bend it works ok and smooth. I put a bit of oil and grease and it helped, I guess a long quality cable is good? or this one works fine with small bend, seems the nicer cables with nylon lining can with hold a bend and function perfectly smooth.










 

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Discussion Starter #52 (Edited)
I did a few test drives, I got it dialed in better so far, I guess I forgot that cause of SRT intake and the R-ECU it was always pretty low on RPM's

Its also pretty neat to see the ECU move the Slave throttle CAM...


Here is a video of it in action
http://youtu.be/1ZUgzc055O0
 

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Discussion Starter #54
So far I have a little over 100 miles on it :) everything is running good, tired cruise control all perfect

Sent from AutoGuide.com Free App
 

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good stuff, does seem pretty responsive.
in for while driving videos
 

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Discussion Starter #57
good stuff, does seem pretty responsive.
in for while driving videos
Why do you need driving video? the car drives for 95% exactly as it did before :)

I can put up a video but all your going to see and hear is an IS that is close to stock, an IS with SRT intake, aftermarket ypipe and muffler.:suspiciou
 

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Discussion Starter #58
yesterday, I discovered a vac leak, it was a hose that through the zip tie tension (you can see the zip tie in the video and can guess which hose it was heh) and heat from the engine slipped off, but there was a minor leak as well, a hose that I changed due to the OEM one cracking while I was taking more then I needed to of off the intake lol. All is fixed the OEM clamp was not tightening enough, so I replaced it and now I should have no leak, and my idle is back to normal :cool:
 

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Discussion Starter #59

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Good work! Great to actually see someone follow thru with an idea like this.
 
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