Okay so I'm going to tackle this and just use this thread to chronicle the job, as I'll be taking care of the injectors and also while things are apart, pulling both complete intake and exhaust manifolds off to thoroughly clean them (mainly the intake) and then reinstall with all new gaskets and harware.
Rather than fool around with aftermarket "upgrade" or retrofit injectors, I'll be having my spare set of OEM injectors refurbished. I haven't settled on by whom yet, but I've sent out a few emails to reputable shops. So far I'm looking at CS Performance, RC Fuel Injection, Witchhunter Performance here in Washington, and Mr Injector (very nearby, in Coeur D'Alene). I'm also considering (of course the dreaded "while I have things apart" line of thought) sending out my spare throttle body to be bored 3mm over. I keep waffling on that one though so I haven't made up my mind. I want to, but I don't really want to plunk down an extra ~$200 for something that's not a necessity at this point. OTOH I've already got an upgraded exhaust, so it's very tempting to just get it done and see what improvement there would be on highway trips with long grades.
At this point, I'm in the process of collecting the parts and hardware I'll need to do this job. I've been on Partsouq looking up all the hardware and gaskets. Obviously some are a bit concerning as they show unavailable or just can't be found in their system, so I'm working with
@ToyotaMatt and
@cruiseroutfit to source all the correct hardware and gaskets. I'll be using OEM spec gaskets save for a Remflex I'm using for the cylinder head to manifold gasket. I say "OEM spec" because OEM isn't available anymore for the throttle body and intake manifold gaskets, but I'll still be using fiber/paper gaskets like what the OEM parts were. I will NOT be using any RTV or FIPG in lieu of a gasket.
So far, here's the list of gasket and hardware part numbers verified and cross-referenced between Partsouq and ToyoDIY. I had initially sorted this list by what parts they were for, but decided it might be best to sort it by hardware type instead.
GASKETS
Cylinder head to manifold gasket: using Remflex 7015 gasket in lieu of OEM
Throttle body gasket: 22271-61010 (NLA from both Toyota and Fel-Pro) -
@cruisermatt may be able to cut new gaskets at his shop
Surge tank to lower intake manifold gasket: 17176-61020 (NLA from both Toyota and Fel-Pro) -
sourced from @cruiseroutfit
Cold start Injector gasket: 23293-74010 (NLA from both Toyota and Fel-Pro) -
another that @cruisermatt might be able to provide
Manifold to downpipe ring gasket: 90917-06004 (x2) -
I used Remflex 7016, but be sure to not torque flange nuts more than 22 ft-lbs with these
SEALS -
I've often reused copper ring seals if they don't have visible corrosion and NEVER had a leak; but opted to have extras handy just in case needed
Cold Start Injector upper copper ring seal: 90430-08009 (substitution: 90430-08014)
Cold Start Injector lower copper ring seal: 90430-08011
Fuel pulsation damper upper copper ring seal: 90430-12005
Fuel pulsation damper lower copper ring seal: 23232-28010
STUDS
Head to manifold stud: 90116-10150 (x4) -
I ordered six and used the extra two with the corresponding washers and nuts in lieu of the two 90119-12069 bolts; an alternative hexalobular bolt is 90116-10117 (thanks @OGBeno )
Lower intake manifold upper stud (for fuel rail): 90116-08108 (x3)
Lower intake manifold bottom stud (for surge tank): 92132-40825 (x2)
Manifold to downpipe stud: 90116-10087 (x4)
WASHERS
Head to manifold washer (for studs): 90201-12004 (x4) -
Get six
NUTS
Head to manifold nut: 90170-12211 (x4) - Again, g
et six
Manifold to downpipe flange nut: 90179-10070 (x4)
BOLTS
Head to manifold bolt: 90119-10038 (x8) -
These are an M10 bolt whereas the studs and other two bolts are M12, so the same studs are not a viable alternative. I reused these, only because it takes considerably less torque to seal against the Remflex gasket. I strongly advise against reusing if you use an OEM gasket
Lower intake manifold to surge tank bolt: 91621-40830 (x7) -
These can break on reinstallation if reused, so best to make sure you replace them
Banjo bolt (cold start injector & fuel pressure regulator): 90401-08004 (x2)
MISCELLANEOUS PARTS
Fuel pulsation damper: 23207-46010
Fuel rail bottom mounting spacer: 90561-08023 (x3) -
These are likely just fine to reuse after a good cleaning with a toothbrush and some dish soap, as long as they're not physically damaged; same applies to the top mounting spacers
Fuel rail top mounting spacer: 90560-08024 (x3)
Harness side fuel injector connectors (x6, have not yet found part number); T
hese can be sourced through @ToyotaMatt
INJECTOR PARTS -
Pintle caps and upper O-rings are typically provided by the injector shop if you're using refurbished injectors
Injector upper grommet: 90480-13005 (x6)
Injector vibration insulator (NOTE this is NOT the pintle cap): 23291-73010 (x6)
Injector lower O ring (for spacer): 90301-19006 (x6, likely provided by injector shop)
Injector spacer: 90561-10004 (x6)
It's funny that the upper intake manifold (plenum) is referred to in Toyota nomenclature as the "surge tank" and only the lower section is referred to as the actual intake manifold.