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Discussion Starter · #1 · (Edited)
EDIT: This thread began with me asking what throttle body options are out there for a FFIM conversion using the GTE upper manifold but it morphed into me covering the particulars of the GTE FFIM conversion.

Original post:
Does anyone know if there are some common "go-to" DBW throttles that 2JZ guys typically use?

I'm finally getting around to fitting a GTE upper manifold to my GE lower using the supra vworld adaptor.

The GTE upper I have is from a VVTi engine, but didn't come with a throttle body - so I'm on the hook for finding something suitable.

I'll be using an ECU that is well capable of running a DBW style throttle, and in fact I think I'd like to use DBW so that I can calibrate cruise control, idle control, traction control, throttle blips for downshift, etc...

The easiest option seems like buying an OEM Aristo throttle body, but seems those are rare and expensive. I've seen some used ones on eBay for ~$500 which seems crazy to me when you can buy a perfectly good used GM throttle for $25-50. I'm fine with making an adaptor to mate the throttle to my upper manifold, and fine with using a different connector and pinout.

But... Was hoping I wouldn't have to reinvent the wheel if there is already a common approach that works.
 

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Do a search on here for the Tundra throttle body. Some guys have used them when doing a 1UZ/2UZ throttle body/intake which is larger than the stock 2JZGE size.
 

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Discussion Starter · #3 ·
Thanks for reply. It seems about any 70-75mm DBW throttle will work fine; I'll likely just go with one for a GM 4.3L V6... No reason for one of the giant 90mm+ ones.

The bigger issue, however, is I'll also need to eliminate my OEM throttle pedal - as any replacement throttle will not have the provision to receive my throttle cable. Instead I'll have to install an accelerator pedal with position sensor built in. Kind of a bummer because I don't want to lose the IS300 pedal with the brushed aluminum face. I guess I'll have to figure out a way to graft the IS300 pedal face onto a GM (or similar) style accel pedal.

Again, any links to info on this already being covered would be very welcome. Hate reinventing the wheel.
 

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Garagewhifbitz sells a kit to do just what you’re wanting. Not suggesting you buy or don’t buy, but an enterprising guy like yourself could look at the contents and diy the same thing on the cheap.

DBW kit

You’ve pretty well nailed it on the gas pedal, too. Our stock hybrid mechanical/dbw throttle setup forces a swap to a new pedal, like you said. Turning to the Supra crowd again, they use an SC430 pedal. Not cheap though, and I’ve heard Toyota wants a sc430 vin before selling the part. Discourages folks like us.
 

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Discussion Starter · #5 ·
Thanks so much for that link. Looks like a solid setup and almost exactly what I need. Seems like the direct bolt-in accelerator pedal is meant for Mark 4 and not IS300, but maybe they're the same?

Also, I wonder if this is available elsewhere directly from the USA? A lot of the stuff they sell is USA stuff but their prices are basically same as what you'd expect to pay in USA, except they're in pounds sterling instead of USD - making it far more expensive to buy from them. I'd give $650-700 for a turnkey setup like that instead of needing to fabricate and do it myself, but $1k is getting pretty steep.
 

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Thanks so much for that link.
No problem man. I’ve not tried it, but I’ve read the SC430 dbw accelerator pedal will bolt right in to the IS300. If you could locally junkyard source the SC430 pedal and Bosch TB, then maybe Garagewhifbitz would sell just the TB adapter? The rest is just wiring/tuning.

Edit: Here’s an adapter that’s a bit cheaper

and This is the garage Whif Bitz piece. Guess it boils down to how much adapting you want to do, to the existing intercooler piping. I imagine the gwb would be cheaper/less headache if you’ve already got the ic plumbing sorted.
 

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Discussion Starter · #7 · (Edited)
You rock. That EFI Solutions adaptor looks nice, and the 68mm throttle will fit the opening in the GTE upper plenum nicely. I suspect that's why they chose to design their adaptor around that throttle.

[Edit: The EFI solutions throttle body adaptor is a well made piece, but unusable because it places the throttle WAY too high and forward to fit under stock IS300 hood. To get it to fit, you'd need to chop a hole in the hood to clear the charge pipe and most of the throttle. I'm moving onto building an adaptor elbow that bolts onto the manifold and provides a ~45º bend to move the throttle down and slightly outboard - pointed directly at the (tight and only) space the charge pipe must come up through.]

I did a bunch of sleuthing yesterday for various Toyota accelerator pedals with position sensor (APPS) built in, and then cross referenced the images against the one shown in Garage Whif Bitz kit. It is almost certainly from 2001-2005 Lexus SC430. I found a new one on Ebay for $235 so I ordered. Hope it is a direct fit into the IS300. I don't mind slight modification to fit the brushed aluminum pedal face of the IS300 onto it, but if I'm in for fabricating a bracket and custom fitment - I'll sell/return the SC430 pedal and just get a generic GM Racing one for $95.

Looking at the area where my charge pipe will need to come up from below, to attach to the throttle - there's stuff that's gonna have to move. I've done some searching/reading around about this and understand the need for a remote power steering reservoir and of course the special fitting for the suction side of the PS pump. I've ordered one of those already, but it looks to me like the high pressure line and pressure switch will be in the way of the charge pipe too. Also looks like the PS cooler lines will be in the way of the charge pipe. Am I mistaken? I haven't seen where people have written about this... Any intel or links would be appreciated.

This FFIM upfit is a pretty serious re-arrangement!
 

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high pressure line and pressure switch will be in the way of the charge pipe too. Also looks like the PS cooler lines will be in the way of the charge pipe.
Yep all that mess is in the way. I bought a gte back when it was like 1700$ to my door, so it had a remote PS pretty much setup already. Didn’t have to bootstrap much. I deleted the PS cooler (been fine 4 years but I do not track race it) so I didn’t have to mess with that either. GTE didn’t have that “idle up” pressure sensor, so I didn’t contend with it. I can take a pic or two so you can see that charge pipe/power steering pump area, if you’d like. I put my maf sensor there, so it won’t look exactly like yours but may give you an idea of what you have to work with.
 

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Discussion Starter · #9 ·
Update on this:

I tried multiple sources to acquire the SC430 accel pedal and came up empty handed. This included genuine Toyota parts houses and various online salvage shops. I tried ordering a couple times from suppliers on ebay - only to receive an email a few days later they don't actually have one to sell. Some further sleuthing revealed Toyota has these on lockdown and allegedly only releases them to dealers that demonstrate they have an actual SC430 in their shop with all diagnostics and troubleshooting indicating a new pedal is needed...

So I ordered a generic GM accel pedal. Summit sells it as the GM Racing one, but it's basically the same unit GM uses in everything. I ordered mine thru Rock Auto for a 2006+ Corvette. I'll need to fabricate an aluminum bracket that picks up the two bolt holes in the IS300 for its pedal, and then provides new holes for the GM pedal.

I intend to cut off most of the GM lever and weld the IS300 lever on, so that I retain that OEM IS300 look.

Overall the size/shape of the GM pedal looks reasonable for this application.
 

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Update on this:

I tried multiple sources to acquire the SC430 accel pedal and came up empty handed. This included genuine Toyota parts houses and various online salvage shops. I tried ordering a couple times from suppliers on ebay - only to receive an email a few days later they don't actually have one to sell. Some further sleuthing revealed Toyota has these on lockdown and allegedly only releases them to dealers that demonstrate they have an actual SC430 in their shop with all diagnostics and troubleshooting indicating a new pedal is needed...

So I ordered a generic GM accel pedal. Summit sells it as the GM Racing one, but it's basically the same unit GM uses in everything. I ordered mine thru Rock Auto for a 2006+ Corvette. I'll need to fabricate an aluminum bracket that picks up the two bolt holes in the IS300 for its pedal, and then provides new holes for the GM pedal.

I intend to cut off most of the GM lever and weld the IS300 lever on, so that I retain that OEM IS300 look.

Overall the size/shape of the GM pedal looks reasonable for this application.
Thats odd that Toyota cares so much about that lol.
 

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Discussion Starter · #11 ·
Thats odd that Toyota cares so much about that lol.
Not really. Toyota only built about 70,000 of these vehicles and it has a unique accel pedal part number not used on any other package. I'm sure they made extra pedals as service parts, and are not interested in making a new batch of them. When the inventory control system starts showing a depleted supply, they have to ration out the remaining parts to ensure they are only being used as necessary.

Basically, Toyota cares about supporting actual customers in actual need - rather than catering to hotrodders.
 

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Discussion Starter · #13 · (Edited)
I'm gonna try to update this thread with progress on my DBW throttle arrangement for the FFIM conversion I'm working on. I have another thread where I was discussing the required flanges and how I'm going to use a generic Bosch 68mm DBW throttle on the GTE upper manifold.

That thread is here: GTE manifold throttle weld flange

But all future updates will be done right here... Mods, if you can sorta merge the threads, that would be cool.

Anyway, I bought a Generic GM accel pedal, which requires fabrication of a mount, as well as modification so that it uses the IS300 accel pedal facing, and puts it in the right spot in the footbox.

So I mounted the accel pedal in the vise, pinching the lever itself with some sockets, just above where I wanted the bend to begin. I wrapped a wet towel over the APS and hinge mechanism so they wouldn't get cooked by the rosebud torch I used to heat it:



Kinda eyeballed it about how it needed to be and this this is what I came up with:



Starting with a 1/4" thick plate of aluminum, I traced and cut out the footprint of the GM accel pedal so that it has something to mount to:



You can also see I've cut off most of the extra pedal lever from the GM pedal, and cut/bent the IS300 pedal so I can weld the two together. The mounting plate will be bolted to the firewall using the original IS300 pedal bolt holes. However the GM pedal base totally covers the IS300 mounting holes, so I'm going to use some M6x1 50mm flat head cap screws, countersunk into the plate. Then two ~1.25" long aluminum standoffs between the firewall and the plate. Still need to do that part, though.

Anyway, here's another shot of the GM/300 accel pedal marriage, ready for weld:



Once it's all fit, I'll do some finish work and paint so that it looks respectable.

Also, I've always hated the position of the IS300 throttle pedal - too hard to heel/toe - even with size 13s. The pedal face is too deep in the footbox in comparison to the clutch and brake, and it is too far inboard. So the new pedal arrangement is moving the pedal outboard ~1", lower in the car ~1/2" and ~1.5" rearward in the car. Hopefully that'll be ergonomically correct. But hey, adjustment only takes a little bending and/or welding. Trying not to overthink this too much - which is a bad habit of mine.
 

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Discussion Starter · #15 ·
Update:

I've got my DBW accel pedal arrangement finished and installed. Still waiting on flanges from laser cut so that I can fabricate the adaptor elbow for my throttle body.

Here is the accel pedal, bracket and hardware ready to install:





Bracket installed on firewall:



Accel pedal mounted onto bracket:



And accel pedal position in the footbox:




It's not quite as close to the brake pedal as I was planning, but it's def not as deep in the footbox as OEM. I think it's workable as-is. Not gonna modify it until I've driven it a bit.
 
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