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Discussion Starter #41
if you read the install doc up on top, reasons are posted to use the IS tranny.

it is generally know that i CAN hold around 400rwp depending on tq and what you have to support it as well as the condition it was in before you boosted.
 

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how much power does the stock auto tranny can hold?

I believe its gonna break eventually since it wasnt designed for this high HP

isnt it better to use the aristo tranny in this case?
i think its a 4 spd automatic.
 

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Discussion Starter #44
again all this is stated in the install doc up on top :approve:

During the process of my Aristo swap here is what i found.

1. The tranny (or bellhousing rather) WILL bolt up to the stock block.
2. The tranny is actually LONGER than the stock tranny so your drive shaft is PWNED!
3. The flange on the end of the tranny is COMPLETELY different than the stock auto so your PWNED there too.
4. The Aristo tranny is 4sp and stock is 5sp (please don't PWN yourself on that one )
5. IS ECU don't know JACK about the Aristo auto PWNED Yet again.

Keep the stock auto and build it or at least VB uprade.

Hope this helps
 

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Just curious - did you Aristo swappers opt to change out the oem jdm side feed injectors and fuel rail for the usdm GTE top feeds? It seems parts are more plentiful on the usdm side and better choices as far as larger injectors, etc.. Also, are there any limitations to using the oem Aristo FPR?

Thanks!

*If this takes the thread off topic feel free to delete. I'm just curious around the fueling aspects people took with this swap.*
 

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All GTE injectors are side feed. You can swap to the USDM injectors if you like. Nothing wrong with the Aristo FPR. It just works with OEM reliability. How much hp are you shooting for?
 

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Without this crap physically in front of me I'm just shooting off what I've 'read' from different sources. Regardless, I'll be going with a 700ish cc injector and whatever rail is best suiting. An Aeromotive FPR for $150 probably isnt a bad investment either. As it stands, the stock twins will be replaced for ease of fitment (and knowing full well that going single will only be a matter of time for me). :)

Keep up the good work!
 

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You can convert to a top feed rail and have access to cheaper top feed injectors.
 

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Teck,

If I keep the aristo fuel rail and injectors, is there a plug for a fuel return line? or do I have to tap the rail?

If I go usdm fuel rail and injectors, is there also a plug for a fuel return? or like the other do I have to tap it?

Cause I was thinking about gettin a custom rail made by another member on here.
 

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You've said your hp goal is 400 in another thread...y all the effort to swap out something that works?

The Aristo already is setup to use a return system.
 

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You've said your hp goal is 400 in another thread...y all the effort to swap out something that works?

The Aristo already is setup to use a return system.
Thats me being retarded about it. I didnt know that it was already set up and that all I had to do was run the line. I have not had a chance to look at my motor for too long.
 

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how much better can a fuel return system be? what would the benefits be with an aftermarket system? It's just sending fuel back...right.
Teck, correct me if I'm wrong, but how much of a difference did you have to tune around going from a 40psi constant fuel pressure to a variable fuel pressure dependent on vacuum?

Hypothetically speaking I would think the injector pulse width time for one tune on the same engine but with 40psi constant fuel pressure would be slightly different than an ECU for the same engine that uses an FPR that uses a vacuum reference. IMO it would be simpler to tune from scratch (injector pulse width wise) with a car that has the vacuum FPR setup than a constant fuel pressure setup (were you would have to tune around 40psi at the injector squirting out more or less fuel dependent on what pressure is in the cylinder). So IMO the FPR does some of the tuning for you, but if using an OE ECU already tuned for 40psi constant, there must have been some tuning all around the spectrum to work with the variable of now introducing an FPR to the system. (and this would be why the TE S1 kits would need a one way valve so that their FPR could not see vacuum, but only boost).

If all this is true, I would have thought tuning with a piggy around the OE ECUs maps would have been tricky at the least with an FPR system. Was this a task you had to do or was it hardly a problem, did you install a one way valve or do I have it all wrong completely?
 

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how much better can a fuel return system be? what would the benefits be with an aftermarket system? It's just sending fuel back...right.
You will run out of injector without a FP riser in the loop.
 

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Teck, correct me if I'm wrong, but how much of a difference did you have to tune around going from a 40psi constant fuel pressure to a variable fuel pressure dependent on vacuum?

Hypothetically speaking I would think the injector pulse width time for one tune on the same engine but with 40psi constant fuel pressure would be slightly different than an ECU for the same engine that uses an FPR that uses a vacuum reference. IMO it would be simpler to tune from scratch (injector pulse width wise) with a car that has the vacuum FPR setup than a constant fuel pressure setup (were you would have to tune around 40psi at the injector squirting out more or less fuel dependent on what pressure is in the cylinder). So IMO the FPR does some of the tuning for you, but if using an OE ECU already tuned for 40psi constant, there must have been some tuning all around the spectrum to work with the variable of now introducing an FPR to the system. (and this would be why the TE S1 kits would need a one way valve so that their FPR could not see vacuum, but only boost).

If all this is true, I would have thought tuning with a piggy around the OE ECUs maps would have been tricky at the least with an FPR system. Was this a task you had to do or was it hardly a problem, did you install a one way valve or do I have it all wrong completely?
Excellent observation and this is one of the tuning nuances that most people don't even get into, let alone understand.

I will leave it at this - absolutely true and yes, this makes things tricky.
 

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Just goes back to the question someone asked - why use the stock FPR which has constraints or limitations... RR FPR FTW ;)
 

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So tell me...what are those supposed "constraints or limitations?"
 

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So tell me...what are those supposed "constraints or limitations?"
^TBD, I dont know. Key word is supposed-What exactly are the flow rates or properties around the Toyota FPR? Where does it crap out with larger injectors pushing an excess of fuel off to be sent back to the tank? A 40psi constant flow rate vs variable vacuum controlled or rising rate is significantly different when it comes to tuning. All I'm saying is for $150 I probably care not to even know...I'll be opting for a rising rate fpr that I know I can tune satisfactory with an E6x.
 

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Not sure if u'r talking about the IS static regulator or the Aristo rising rate regulator.

The Aristo, like all GTE's, already has a vacuum/boost reference rising rate fuel pressure regulator. No point spending money on something that is already there and plenty capable.
 
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