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I checked the Link/Panic ecu. I don’t think it’s automatic compatible.
It will not control the automatic.

Controlling this automatic without the OEM ECU comes up often here. The common response is the MaxxECU can be made to control the Toyota automatic.

I don't see why a Microsquirt couldn't be used as a standalone controller for the Toyota automatic. Megasquirt has firmware to use the Microsquirt as an automatic trans controller, however they don't offer base calibrations for Toyota. I'm not an automatic expert by any means, but I'm pretty sure they all depend on speed signals, line pressures and PWM control of solenoid valves - so I believe Microsquirt would provide you with the knobs/adjustments required to make it work, so it'd come down to hammering out a viable calibration. I'm 2/3 tempted to buy myself an automatic IS300 to try this out.

Additionally, the Microsquirt will operate on a CANBUS, so if it could be made to work, it could be bussed into the Haltech/Link/etc to share data.
 

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Discussion Starter · #23 ·
An align-hone is when the main bearing bores are honed to ensure all 7 form a straight and round tunnel.



The stock GTE pistons are not forged. That said, if your intent is to have a machine shop do a real hone on your cylinders - they're going to end up too big for even standard size forged pistons. You'll need to go oversize if you want a real hone, because they'll remove at least several 0.001's of an inch - and that's on top of the several 0.001s of bore wear you already have.



A 255 lph Walbro "high pressure" pump will do mid-400whp no problem on pump gas, but not on E85. I have a thread where I show how to fit one of the big "Hellcat" Walbros into the stock hanger assembly. I recommend Injector Dynamics for injectors. Pricey, but good.
Thanks for your feedback and clarification that the stock GTE pistons are not forged. Will keep the align-hone thing in mind as well regarding the main bearings when we open up the motor and take a good look at it.

I think I'm going with Wiseco or Clevite forged pistons once we determine how the cylinder shape is and determining what bore they need to be. As for the connecting rods I am leaning toward the stock GTE rods as they should be forged and able to hold up 500+ hp I can get a set for about $700 brand new @ Driftmotion, plus I already bought the ARP rod bolts. When it comes to the stock GTE rods + ARP rod bolt combo, is there anything to keep in mind here so that everything aligns perfectly and does not cause issues down the road?

As for the fuel system, going with the 255lph Walbro fuel pump + injectors will seem to do the trick. Would you mind sharing the thread you mentioned for fitment and installation?

Also another question will the stock intake manifold hold up the 420 hp without issues?
 

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When it comes to the stock GTE rods + ARP rod bolt combo, is there anything to keep in mind here so that everything aligns perfectly and does not cause issues down the road?
It's kind of bad juju to fit aftermarket rod bolts without rehoning/resizing the big ends of the rods. The issue is stronger/better bolts will induce stress into the rod differently than weaker bolts - and thus pull the shape out of round. I would not spend $700 on stock rods, then more money for ARP bolts, and then more money for re-honing. Instead, I'd just buy a good set of aftermarket rods complete with ARP2000 bolts already.

Would you mind sharing the thread you mentioned for fitment and installation?

Also another question will the stock intake manifold hold up the 420 hp without issues?
Here is my thread detailing installation of a big Walbro into the stock hanger: Walbro 450 or 480 or 525 or Hellcat fuel pump in IS300...

Stock intake manifold is more than sufficient for 420hp.
 

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The issue is stronger/better bolts will induce stress into the rod differently than weaker bolts - and thus pull the shape out of round. I would not spend $700 on stock rods, then more money for ARP bolts, and then more money for re-honing.
Definitely agree with this. It’s been tested quite a few times. It’s been shown that the stronger bolts deformed the caps slightly. Even if a vendor say it won’t happen, testing still shows that it does. Not exactly 2jz, but just google Katech bolts and LS1 to get more information. You’ll have to rehone with arp bolts.
 

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Discussion Starter · #26 ·
It's kind of bad juju to fit aftermarket rod bolts without rehoning/resizing the big ends of the rods. The issue is stronger/better bolts will induce stress into the rod differently than weaker bolts - and thus pull the shape out of round. I would not spend $700 on stock rods, then more money for ARP bolts, and then more money for re-honing. Instead, I'd just buy a good set of aftermarket rods complete with ARP2000 bolts already.



Here is my thread detailing installation of a big Walbro into the stock hanger: Walbro 450 or 480 or 525 or Hellcat fuel pump in IS300...

Stock intake manifold is more than sufficient for 420hp.
Awesome thanks for the heads up. I am going with the Eagle Rods with the ARP2000 3/8 bolts which is a great value right now at $599 and I've read people run much higher HP (700+) reliably.

I've looked into the AEM infinity 506 ECU and I think I am leaning towards that one as it does DBW (Which means I can run stock throttle body and setup right?) and has a PNP harness for either auto/manual trans and will also work alongside my stock ECU to control the auto trans. Any thoughts on this ECU and planned setup?

Thanks for sharing your thread detailing the install I'll follow it and get mine going using it when boost time comes in the very near future. Do you have an idea how much the stock intake manifold can handle?

Kind Regards,
kaiz3n
 

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looked into the AEM infinity 506 ECU and I think I am leaning towards that one as it does DBW (Which means I can run stock throttle body and setup right?)
Yep, that’s the exact setup I am running. You will have to do the legwork to see if the PNP harness is set up to control the stock throttle body. Most of the PNP harnesses I have seen are pretty generic and share the sensor data with the stock ecu, and only divorce Spark and fuel control from it. Meaning DBW is still on stock ecu. It would be easy to look at a pinout of whichever brand harness you want, and see what all it’s wired to do.
 

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Do you have an idea how much the stock intake manifold can handle?
Not exactly sure what you mean by limit... A maximum amount of power that can be made with it? Maximum amount of boost it would take before breaking?

I think, at a certain point, extra power can be made by switching to a different manifold - but there are always tradeoffs. I recall seeing a notable 2JZ tuner doing an A-B-A test of a stock GTE manifold vs a short-runner Plazma man manifold. I think the GTE manifold made ~850whp or so, and the Plazma made 875 or 880...so about 30whp better. However, the Plazma was down on power everywhere below 7000rpm.

And what would've happened if he had dialed up an extra 2psi boost on the GTE manifold? It likely would have matched or exceeded the Plazma.

The point is, don't worry about the stock manifold unless you are searching for every last bit of available power - or - you want the look of a forward facing manifold.
 

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Also, some notes on controlling DBW via a non-stock ECU:

Pay careful attention to how safeties are implemented! I'm not intimately familiar with how AEM 506 is arranged, so I have no opinion on it specifically, but having multiple levels of safety incorporated into a DBW throttle is essential.

Back in early days of DBW, the Germans created a consortium named EGAS for engineers and calibrators to get together and discuss the dangers of DBW, and how to implement it safely. EGAS published a set of standards for the automakers to follow. Toyota chose not to follow EGAS protocols, and instead came up with their own approach. Later, Toyota had the "unintended acceleration" disaster, lost lawsuits, and was forced to comply with EGAS standards.

Just be sure the DBW approach of your chosen ECU has a well thought-out safety protocol.
 

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I've looked into the AEM infinity 506 ECU and I think I am leaning towards that one as it does DBW (Which means I can run stock throttle body and setup right?) and has a PNP harness for either auto/manual trans and will also work alongside my stock ECU to control the auto trans. Any thoughts on this ECU and planned setup?

Thanks for sharing your thread detailing the install I'll follow it and get mine going using it when boost time comes in the very near future. Do you have an idea how much the stock intake manifold can handle?

Kind Regards,
kaiz3n
Correct me if I’m wrong but I think the automatic needs the stock ecu to control the DBW for it to work. Not a problem with the manual.

The stock TB and intake manifold setup is good for quite a bit of hp. I made around ~550hp on the stock intake system. I removed the ACIS (butterfly valve in intake manifold) for easier tuning purposes. Boost leaked out the shaft for the ACIS in my case and I had to seal it. Besides that nothing else is needed to make good hp on the stock IM setup. I doubt you have to worry until ~800hp.
 
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