Initial Development And Prototyping Of A 102 mm GM LS Throttle Body On A Supercharged Tundra

I asked about my pressure loss he responded he was out. (Paraphrasing)

 

Well that’s unfortunate

 

Agreed, he is an amazing person.

 

What a crazy 180. Hope all is well on his end.

 

This is the Perfect Lamba owner's email, he said it's OK for me to share it:
amalanssari1@gmail.com
I don't know if they still make the adapter and harness though.

 

Sweet, I'll reach out to them, thank you sir!

 

Keep us posted if you get a response.

 

Yes! let me know, I'll hold to order the rcf then.

 

Thanks Viktor!

 

Final hurdle would be an adapter plate.

 

Easy hurdle. Send me the dimensions.

 

Perfect Lambda showed an adapter plate on their IG post for the wiring adapter. If not, we've got our own local machinist

 

Will do, if this harness comes to fruition then its game on lol Whipple inlet is 102mm vik's vid shows 103mm TB so would work great lol

 

I got an email response:

Hello Bryan,
I have a few of them in stock, but I have some issues with coding the board.
I will try to fix the issues and get back to you next week
Thanks,

 

Yes!!!! How much? I’m pumped if this happens.

 

Not sure, that was the entire email...hopefully will find out more and get an order placed next week.

 

I sent a follow-up email on Wednesday, no response yet...

 

Damnit. @snivilous Figure this out so we can run LS throttle bodies lol

 

I'm not an electrical engineer

Send me a tundra and LS one and I'll combine them somehow though

 

Instead of clogging the supercharger thread, I'm going to start posting my ramblings here and see if we can work through a solution.

Found this on a Titan (Nissan) board:
Tundra:





pins color closed voltage open voltage (thanks texasranger96)

6 red/y .9and .7 all the way closed 4.4 and ramps up all the way no plateaue
5 y 4.9 4.9
4 y/blk 2.6 and 2.2 all the way closed 4.9 and starts to plateau at about 75*, 90* being all the way open
3 blue grnd grnd
2 red 12 11
1 grn 11 12

Titan:

Blue w/Black - TB motor - 0-5V
Blue w/White - TB motor - 5-0V
Yellow - Sensor Power - 5V
Red - Ground
White - TPS - 5-0V
Black - TPS - 0-5V



LS2/LS7:

PIN ID LS2/LS7 90mm
A.) ACT2
B.) ACT1
C.) +5v TPS Reference – Common to both TPS’s
D.) TP1 Signal 0-5v
E.) Common Ground
F.) TP2 Signal 5-0v

This matches with what Victor had mentioned with GM using a rising and falling TPS signal. Most should be 0-5V as it's pretty standard.

Toyota has 2 signals, both raising, but it appears VTA is standard 0-5V (0.5V-4.5V actual) but VTA2 has a ~2.5V offset, so it's 2.5-5V. That rules out using VTA(1) for both signals.

Throttle stepper motor:
From Victor's first video it appears the stepper motor to actual move the TB blade works correctly, but then the TPS signal causes an error and likely CEL.

TPS:
If this was a simple 0-5V to 5V-0 invert, an Op-amp could be designed to cover it (I wish I would have payed more attention to these in college) I still think an Op-amp with a 2.5V additive offset might work, but the curve could cause an issue. An Arduino may also be able to process this, but I'd rather not have one inline on my TB.


So now, anyone interested, let's poke holes in the above info. I could really use a couple voltage readings of VTA and VTA2 at idle and WOT to compare to. My truck is 1,200 miles away and won't be here for another couple weeks. I also have a message into a MegaSquirt guru in my VW club to pick his brain on this.

OR our tuner buddies in the UAE can come thru and all of this is for naught.

 

I think I found a possible solution:
http://www.torquerush.com/d2a

Common Uses
In D to A mode the D2A can be used to decode a GM LT digital SENT protocol throttle position
sensor signal and convert it to the corresponding dual 0-5V analog signals. The signals can be rescaled and/or inverted as needed.

 

Looks promising!

 

That's badass! Nice find and research!

 

Looks promising, I ordered one last night and sent them an email...got a response this morning:

My Email:
Do you know if this could be used to convert GM throttle body signals
for use with a Toyota ECU? Specifically the 3UR-FE engine ECU? Thank
you for your time.

Response:
It has been used on Toyota trucks before. We do have one Toyota TB preset setup in the app. I believe that Toyota TB has one TPS signal plateauing before the other reaches its maximum value. If your stock TB differs from this one, you can first connect it to the D2A and record its output ranges using the app. (Send us that recording) Then use those values when programming the D2A.

I see that you ordered the GM truck harness. You will need to wire the end that usually connects the the GM stock throttle connector directly to your factory wiring, or find a connector that mates to your factory throttle connector, if one exists. Or we can supply a connector kit(housing/crimp terminals/seals) to replace your factory connector that will mate with the GM truck harness.

 

OH SNAP!

 

Did you also get a Nick Willams 102?

 

I haven't purchased a TB yet...I'll probably get a cheap unit to make sure it works as expected, before I get the Harrop snout with the integrated 110MM TB.

 

Harrop confirmed the 110mm will physically fit and belt routing will work...only hurdles would be controlling the TB and a new intake solution:

Thank you for reaching out and I’d be happy to help in any way I can. The 110mm TB front cover will work with the 3ur supercharger and belt routing. As you mentioned it will require a custom intake tube to be fabricated. It is designed to integrate with an LS and the control of it will likely be the biggest hurdle. The most common upgrade for the 3ur is the RCF throttle body which can be sourced fairly easy, while the 110mm is typically for drag applications. Please feel free to reach out anytime and I’ll help answer any questions you may have.

 

Excellent, sounds like they can log the TPS signals of the OEM TPS to confirm if it's truely 0-5V for TPS1 and 2.5-5V for TPS2.

I KNEW someone out there had to have solved this issue already. Sounds like it's time to track down a bulk order of Toyota OEM TB plugs and pins to make these integrate nicely.

 

The signal converter and GM engine harness arrived today, and after some quick research I came up with the wiring diagram necessary to convert to a Tundra. Tomorrow I'll get the harness converted and shortened so I can hook it up and test functionality. Because threads are worthless without pics...here's the package including the converter, GM harness, GM engine-side connector and terminals/seals to make a Tundra harness, USB cable for programming, and instructions. Second picture is the inside of the converter where you hook up the USB, last picture is my wiring notes.

**(Throttle body not included, I added to make it easier to understand what goes where)