Sniv Speed Shop - Custom Parts and Design

That Povoke ftw

 

I don't have one yet But Christmas is coming. Might be that time after funds are recouped from buying the kiddos Christmas gifts.

 

I have a 2016 SR5 Tundra.
I have the Genisis Offroad Dual Battery system.
I purchased the G Screen System.
I had the cable run through the firewall then had a mount made for the G Screen.
I got the G Screen Custom mount from Snivs Speed Shop.
I did the install this past weekend.

 

I had to post some of the cool stuff I've made headway on the past week or so. Getting the stock TPS to read without too much effort gave me a lot of hope, and finally having a good 3D printer to rapidly iterate parts is a game changer. I've now printed dozens of setups to test tons of things, and am honing in on a magnet configuration that will do what I want. I'm also a couple iterations deep now on a drive gear and shaft configuration that just might work and uses some mechanical trickery to hopefully fool the ECU with its backdrive requirements while also allowing for a conventional throttle screw.

This was another iteration of the TPS mockup assembly for testing along with an early gear setup.




This is my first shaft setup, this is using a RevA shaft to a coupler to at least work with the RevB throttle body. The final version would be a "one piece" shaft going through the bearings and then still go to a plastic gear that bolts onto the end. This version fit and was presumably functional but the TPS readings went from 20deg to 55deg from full open to full closed so I've been working on sorting that out.



The above setup installed in the 95mm housing. OEM motor, OEM idler, OEM torsion spring, OEM sensor suite.



Last night and today testing voltage and angles so I can make a test bench on my desk so I don't have to turn the truck on and use an OBD reader to see angles every time I iterate.



I also designed a TPS plug today which works great.



I then printed my 3rd TPS test rig which uses 1.5" pucks so I can quickly rotate exactly 90deg and see the TPS voltage output. Using a power supply plugged into the TPS and a multimeter connected to the VTA output and power supply ground, I can quickly pop in different pucks with different magnet geometry and instantly see what the "full closed" and "full open" measurements are and then narrow them in based on my testing from the truck.



And just now, which prompted this post, I got my first magnet configuration that is reading 5V full open and 0V full closed. Stock is a narrower range than that so I'm printing some more test blocks to try and get closer to the stock sensor range (stock is ~0.9V -> ~4.5V), but worst case this new setup I THINK will do the job. Once I have the magnet geometry where I want, I will move that to the updated drive gear design---then HOPEFULLY actually install that on the truck and see how functional it is.

Designing the drive gear setup is pretty straightforward, reverse engineering the hall effect sensor has been quite the task, especially since I have no formal electrical training so all of this has been trial and error and taking notes. Magnetic field orientation, amount of magnets, depth from sensor, radial distance from sensor, clocking, size of magnets, steel inserts, all being tested differently and together takes a lot of time. I'm excited I'm making solid progress and learning a lot, it gives me confidence that this project has potential and maybe this is the key to getting the doors open I've struggled with. I'll post more once I've made more progress, but wanted to do an update before I got too many photos.

 

That's great to see and hear. Do you need the TB I have for anything or retro fit?

 

This is probably a dumb question but hey one mans dumb question is alot of people humor for the day. Once you get the bugs worked out it probably will not benefit a N/A truck will it?

 

Impressive work! You've made some strides on this endeavor this season!

 

Eventually yes, I should be able to make it work. I'll send you a shipping label at some point, and if I get both working I'll send you one of them with the new setup before I order the machined parts for the next revision.

Doubtful, to be honest I don't think it'll be a benefit to hardly anyone. With that said, I won't stop anyone who wants to get it for whatever reason, plenty of people buy equally or more expensive upgrades that probably have less of a performance impact. Somewhat ironically the "market driver" are the people who it won't make any difference for.

 

Like the movie says..... "if you build it they will buy it"............ or is it if you build it they will come? .

 

Awesome!
Hey, it's getting close to the due date. Bet the Mrs is ready. All the best and health for the little arrival of that bundle of joy.

 

Can't love this enough!

LFG Mrs Sniv!! And you, too, Dad. Notice: when they encourage you to grab a leg, you say NO!

 

Hahaha thanks, any time now, the wife is more than ready for it to pop!

 

Big progress today, got the 95mm installed in the truck with a fully functional custom drive gear, and miraculously it worked right out the driveway! Hopefully I don't regret showing pictures down the line, but seems like the only difference that would make is $500 from someone buying one and just copying what I'm doing.



I did a lot more testing the past few days and ended up with a spreadsheet showing magnet layout variations and what voltages and angles they gave. The stock setup uses two really small magnets with a metal tube connecting them. I didn't want to deal with the tube part so early on avoided that, instead I end up with 6x decent sized magnets in this pattern which is giving me the voltage read outs and range of motion I want. A couple iterations to line that up where I wanted in the throttle body and we end up here.



And if anything is learned from this setup, it's that this works with the TPS seemingly great so far. That alone is a massive hurdle cleared and opens up a lot of capability and design choices. At this point the only thing constraining the driveshaft is that I'm using the stock torsion spring, otherwise I have complete freedom and can deviate from the stock layout which is huge.

Now for some of the mechanical trickery. As previous explained, I've been between a rock and a hard place where the throttle angle at idle needs to be very low due to the target idle rpm and because the blade is so large that it flows a lot of air at low angles, but the flip side is that the ECU wants to close the throttle blade and seemingly the amount of remaining angle to close the blade is too small and the truck wants to close it more (like the stock blade) so it ends up throwing a CEL. To get around this, what I did was decouple the throttle blade from the TPS (that ring of magnets) at idle. This is done by the drive gear connecting to the shaft via a spring loaded coupler:





The shaft slides into the drive gear, the two compression springs get squished and that is your nominal position, the two are directly connected when opening the blade. But once the blade is fully closed, the springs can be fully compressed and the drive gear can spin an additional 5deg relative to the shaft and blade, allowing the TPS to appear to back drive even after the blade is fully closed. In the below photo the top/bottom edges are fully seated in the preloaded configuration, and you can see where the springs are there is a gap between the two parts where they are allowed to decouple and compress the springs to trick the ECU.



Additionally, I added a throttle blade idle screw. The throttle blade fully closed position (ie true idle) can be set since the blade can fully close and the ECU won't think something is stuck since the TPS will be free to move. The TPS/drive gear retains the adjustment screw that rests against the torsion spring also, which is required otherwise the torsion spring will fully compress the compression springs once the throttle blade fully closes, which requires the TPS screw and the idle screw to be matched to each other. Essentially since the driveshaft assembly is two decoupled sections, each one needs to stop at the same spot so they act coupled together until the motor attempts to backdrive the drive gear.


Now for my testing: it worked great! It never threw a stuck open CEL which is probably the first fresh assembly that hasn't done that. The blade idle screw also worked. There's some weird nuances I'm still figuring out though. At the end I had some very successful tests, first I was able to get the IAC code to trigger which involves going ~10mph and coming to a complete stop, and repeat that 5+ times, so I was able to start testing for that quickly and was able to throw that code. I then lowered the idle and that code did not pop, perhaps the first real test where no codes at all have been triggered. To do this tough, I had to totally back out the blade idle screw. That seemed to make no difference, I think if the blade was a tighter fit or the body geometry was different it would matter, but where the truck wanted to command the throttle to for idle, I had to back the screw all the way out.

...but then if the truck cooled down, it wouldn't start since it didn't have enough airflow. So the blade idle screw maybe was doing something? After some fiddling with things, I came to some degree of conclusion that the TPS idle screw is what mattered (the only screw a stock TB has). But once the truck is running, that screw does nothing whatsoever. It almost seems like the truck looks at the TPS position at startup and calibrates it to something? Moving the screw and restarting the truck would adjust the idle, so it seemed to do something. It almost seems like the position of the screw is for cold idle, and then the ECU will take over and lower the idle if the engine is already hot. If that's the case, I can eliminate the blade idle screw altogether, and the order of operations is to set the TPS screw, start the truck, check idle, and if it's off then adjust the screw and restart the truck and repeat. This is what I did when I had my last successful test and didn't blow the IAC code, and the truck still started when cold.

Of course it's not all good news. The truck was running pretty lean at idle at the end, so I flashed a previous tune for the 95mm since the idle MAF values were 20%+ out of wack. Whatever that did though seemed to fuck it up, since now it just does the idle 1000-2000rpm pulsing, and I even unplugged the battery! Which is really weird to me. When I first started today I unplugged the battery while installing the 95mm and there was no issue at all, maybe a first when swapping from the stock to the 95. So why did flashing the ECU and unplugging the battery not have the same effect? I'll leave the battery unplugged overnight and see if it starts fine tomorrow, hopefully the battery just wasn't unplugged long enough to reset whatever weird ECU related values were saved (though why flashing the truck changed those values is also confusing).


All in all, a very successful day with hardware back on the truck. With that said, I don't know if this decoupled shaft idea is the way I want to go. It's a lot of complicated moving parts, and you can certainly feel the decouple zone in the throttle. 5deg may be excessive for what's needed to spoof the TPS, hell maybe it only needs half a degree. Multiple times I thought the truck had entered limp mode and really it was just that the drive gear hadn't moved far enough forward to re-engage the blade. There's probably a multitude of ways to tighten it up, but it is a noticeable and combined with the complexity I'm not a fan of it, though if nothing else it'll be used as a stepping stone moving forward.

I think there is an easier way to solve the backdrive problem, I think if the throttle body has a (mostly) sphere cut out of it where the blade goes, then the throttle blade could be sealed up like it's fully closed for multiple degrees of motion:



That could make it so the blade nominally "stops" at 10deg, but it can backdrive another 10deg and the airflow doesn't change. Or you could have one side match the profile of the blade to hug it, while the other side (top vs bottom) could slowly open up, effectively making half of the throttle blade actually open at low throttle to try and help control the idle issues. The one caveat is you couldn't have the blade itself fully seal, and as we've seen even a .005" gap is too much airflow, so having something that doesn't have a true bottomed out "fully seated" spot might be difficult. But I wonder if the blade had like a wiper seal running around it that was squishy, even an O-ring running around the blade, that might work well. I think some throttle bodies kind of do this where they have weird geometry to help keep the low throttle airflow not so twitchy, but they aren't trying to fully seal the blade over a range of motion since they still have hard stops so this is inherently different still.

I'm gonna try to print an insert for the throttle body and then run a smaller blade and see if I can make this idea work, but first will be trying to get the decoupled shaft concept working again on the truck and confirm if everything is working right or what's needed to make the ECU accept it.

 

Badass! Some awesome progress can’t wait to get this dialed and big unit for the Whipple

 

That's great to hear!
One thing I was able to go with a 20% increase in airload with the cells that are within the torque range for the GM 95mm. Combined with a 4% increase in optimum engine torque. There is a little bit of blending to get the inverse pretty close so not to mess with ignition efficiency and not loose timing. I did have a few cells that hit -4.2 retard but I'm getting ready to do some WOT runs. Although we got some torrential rain heading our way!
Nice job working it out. And I'll give it a go when ready.

 

This is intense.

 

Got some frame reinforcements designed for @reywcms truck and they fit awesome. Made some small design tweaks and hoping to get a set sent out to be test fit before putting them up for sale (though as they are now I would think they would be 99% adequate, but the fitment in a few spots could be a bit nicer for welding). These are cut from 1/8" cold rolled steel and box from the front where the OEM box ends to the crossmember in front of the bed.








There's also a rear plate that I don't have a picture of in test fit form for some reason.










There should be a full or partial rear frame section reinforcement kit in the near future too.

https://www.snivspeedshop.com/product/07-21-tundra-mid-frame-plating-kit

 

Incredible job! That scanner has paid for itself so many times! Bravo to your "getting it done!"

 

Nice! Will be on the list for sure!!

 

Let’s goo!

 

@BiggHertz - is this JSON spec?

 

midtravel guys don’t need this… lol

 

Ha...I've heard boxing the frame from cab back helps with the bed bounce. Reduces frame twist etc.

 

All of the above and more. No surprise why other frames are fully boxed etc

 

Yes, if you build it, they will come. I thought the exact same thing.

 

Now my wheels are turnin for a wheelbase shortening project... which will likely never happen lol.

 

I want these and the bed portion if/when they come out, but had a few questions...

How much does the set weigh?

Would adding dimple die holes defeat the purpose?

What are you doing about brake/fuel line placement/serviceability?

 

@snivilous show off that rear section..

 

Solidworks says the mid section plates are 11 lbm per side. I would suspect a full rear set would be about the same, call it maybe 50 lbm total. Dimple dies or just lightening holes I wouldn't say would defeat the purpose, but you're trading some degree of stiffness for making it lighter obviously. In the vertical bending direction it wouldn't make a huge difference since the hole would be at the neutral axis which isn't doing much, lateral bending would take a pretty large hit since then the material is at the most extreme fiber, but there was nothing there to begin with so still would be significantly stiffer than stock (and not like the frame is loaded much in that direction). TL;DR---if you wanted that I think go for it, just having any material boxing it in is a huge improvement.

Haven't thought about brake lines really. I like using nutcerts since they're easy and then could use stock mounting hardware to some degree. I have welded bolts/studs to the chassis and used P-clips which is nice but the threads can get fucked up. Honestly I think the easiest and most elegant is to weld on some zip tie tabs so then the brake line is easily and quickly serviceable. What we will do on Rey's truck I don't know. The brake lines will most certainly be mounted on the inboard face of the frame though, no trying to get fancy running it through the frame. And we might do stainless braided brake lines, hard lines are nice and perhaps have better feel, but there is a huge advantage in my opinion of the ease of routing a soft line and being able to carry a single 12ft spare line in your tool box to swap as a replacement anywhere in the vehicle, and in my experience the brake feel degradation is pretty minimal. All of that to say, I have no idea but have tried a couple brake line/routing setups and personally just having a couple dozen zip tie tabs and welding them everywhere is very simple, robust, and extremely serviceable.