KE25 running gear

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4A-GZTE 20v 1600cc
- Air filter - GT3076 - air/air intercooler - SC14 - water/air cooler - bypass valve - quad throttles -

build parts list...
 
The Plan : 20v 4age twincharger Y= Got/done. N= Not got

Y *20v block
N *Custom engine mounts
N *Knock sensor drilled/tapped into rear position to clear SC
Y *8.9:1 ae101 4agze pistons,
N *Flycut 5th valve pocket to make non interference engine between 20v head and gze piston
N *2nd gen 4age/4agze rods with ARP bolts, upgrade to forged when decent power made
Y *7afe oil pump housing with VR crank sensor
N *Custom 18 tooth cambelt drive pulley with 12 tooth ignition trigger wheel (4a/7a hybrid)
Y *7afe alloy sump with rear rib sectioned to clear steering rack
N *Custom cast gearbox bellhousing 4A-W, fwd bolt pattern suit mickey mouse backing plate + 7afe sump/or 20v brace
N *Winged/baffled 7afe steel pan, possibly w/ external wet pump low on exhaust side
N *Or- option2 - dry sump oil system
N *Thermostatic bypass oil filter adapter, oil cooler, mount remote filter if restricted for space
Y *20v blacktop head and quad 45mm throttles
Y *540cc side feed injectors, ex 3sgte ST205 GT-4
N *2nd fuel feed, rail/injector setup into top of plenum spraying down trumpets.
Y *Cam angle sensor - to be mounted off exhaust cam with single tooth trigger pin
Y *Coil on plug (shortened) 1mz-fe 2-wire coils
Y *3 layer 0.8mm TRD metal head gasket (or 7afe 0.3mm gasket to raise compression), oem 20v gaskets fitted elsewhere
N *ARP head stud kit
N *Exhaust ports enlarged, all ports deburred, valves deshrouded
N *Performance valve springs
N *Custom inlet plenum on silicon joiners
N *Custom water manifold off back of head (for firewall clearance)
N *Custom water outlet at front of head
Y *AE92 remote thermostat mounted under intake plenum behind S/C
N *Custom stainless water pump inlet pipe from thermostat
N *Turbo - sized between a Garrett GT3076 to a GT3582 (ford falcon typhoon GT3040)
N *External wastegate 44mm?
N *Steam pipe turbo exhaust manifold (6boost or )
N *3-3.5" exhaust system
N *Front mount air/air intercooler w/ 2.5" piping
N *Top mount water/air intercooler after SC?
Y *SC14 roots supercharger (2tz-fze Estima w/ 110mm 7rib pulley)
N *Custom SC mounts and tensioner, custom SC inlet manifold
N *Custom crank and accessory pulleys to suit toothed accessory belt
Y *55mm butterfly bypass valve sourced from 3c-te estima (diaphragm operated to suit throttle after SC system)
Y *2tz-fze S/C recirculation valve - stepper motor type for idle/cruise and/or S/C boost bleed
N *Alternator mid/low mounted exhaust side with custom mounts/tensioner to suit
Y *AE92 reduction starter - from smallport 4age (exhaust side).
N *ECU - considering a Link G4+. laptop tuned with lots of features. sequential ignition/injection etc
Y *wide band oxy for tuning purposes
N *CDI ignition?
N *water/methanol injection system?
Y/N *jza80 W58 gearbox w/ hilux front shifter position tail housing. Aftermarket gearset if won't hold together.
N *9" custom chromoly flywheel and h/d clutch (if it holds) otherwise bazda's tilton twinplate + custom fly
N *more saving moneys + sell kidney

How the system works:- (Compound charged).
At idle, the SC is disengaged via a relay to the electromagnetic clutch. Intake vacuum post throttle opens the ABV (Air Bypass Valve). Any inlet vacuum above approx 8" mercury will engage the SC. If SC is engaged and throttle is closed, the air bypass valve (ABV) will be open to recirculate air from the pressure side back to the inlet side via an intercooler (to aid cooling the SC when recirculating). The ABV closes as the throttle opens in a smooth manner which brings on boost progressively. Once the ABV is closed, the engine should see the full 0.5bar (8psi) from the SC. At any stage from here the turbo will start generating boost and feed it into the SC via the air/air intercooler, the SC further compounds the incoming pressurised air forcing it into the engine via the water/air intercooler. When the throttle is released, the BOV will expel total system pressure until the pressure before the SC is depleted. This works in conjunction with the ABV which will then keep air in recirculation dependant on throttle position (inlet vacuum). The SC clutch relay has a delay timer before switching off so SC stays running between gear changes and momentary decelleration.
Note: I'd like to try out both compound and sequential systems for comparison. The following setup should allow me to test both. In theory, the compound system will ultimately make more power (with a better SC), due to having two chargers running in their best efficiency ranges whilst also promoting cylinder scavenging with it's related knock reduction benefits via near equalised pressures in intake and exhaust manifolds. I believe the sc14 will better suit a sequential system. I'd also like to try out a 'semi-sequential' system where the SC spins faster and produces more initial pressure to spool the turbo quicker, but once pressures are compounding, the ABV bypasses a controlled amount of air (not all of it) to reduce the S/C pressure ratio for optimal efficiency on boost.

Pro's
* low end torque
* top end power
*instant boost
*more power than either charger can produce alone (compound boost)
*turn s/c off for fuel economy cruise
*its unique

Con's
*complexity
*cost
*extra weight
*cramped engine bay
*heat
*increased failure rate
*build/tune time

twincharger setup
Engine : 20V 4A-GZ(T)E
 Since this car no longer needs to be daily driven, lets why not boost the crap out of it!
The idea here is to use all the best parts the generations of 4age have to offer, and build them into a beast. The plan is to use the 20v silvertop bottom which has the larger 42mm crank journals, bigger gudgeons and oil squirters (compared to bluetop bigport 16v 4age). A silvertop 20v bottom end is apparently much the same as ae101 4agze with exception of the pistons, but much cheaper to purchase.. and have picked one up for $75. I've now sourced a black-top 20v engine that had run a big-end bearing from which the head and 45mm quad throttles will be used. Turbo will sit on a custom turbo manifold, feeding a front mounted intercooler, custom intake plenum made for the quad throttles with associated intercooler piping and controlled by an aftermarket Link G4 or similar ecu which also gives me the option of installing sequential coil-on-plug ignition so the distributor can be ditched rather than cutting the firewall. A custom water manifold off the back of the head needs to be sorted amongst other things. Some ideas for that here. The water system i plan to run is this.

Gearbox : W58 close ratio 5speed
Need to sort out a suitable bellhousing, either by fabricating a 4a engine flange to the front of a km36 5k/G52 bellhousing, or buy a Niteparts A-W bell, or make my own A-W casting which i'd prefer to use the fwd bolt pattern, then can mate the 4age to a stronger supra W57/W58 gearbox to keep things reliable. A custom driveshaft (lengthened st185 shaft) and gearbox crossmember made up to suit. This then will fit a std 4a-gze sized 9" flywheel/clutch without contact or a twinplate tilton etc. Also on the search for the US spec truck shifter position which is further forwards than even the ta63/ma61 shifter, which apparently is not quite forward enough to come through the factory ke25 shifter hole. Conversion Components shifter is another option. May require an aftermarket gearset if racing/drag racing with slicks.

Fuel delivery:  Plan to use an in-tank lift pump to feed fuel to an anti-surge tank. Sucking from the surge tank is two (sequentially staged) parallel mounted fuel pumps pumping through a new fuel feed line to the high pressure fuel filter in the engine bay, through the fuel rail (possibly a 2nd rail and set of injectors firing down the ports) and pressure regulator then back to the surge tank via a new return line. An overflow pipe at the top of surge tank runs back to the main tank. The tank breather uses the original ke2 vent pipe to the engine bay where a small charcoal canister and vsv burns off fuel vapours on decel and idle.

Electronics: Wire in programmable ecu. Alarm installed with super trick anti-theft, tracking and paralysis inducing devices. Battery relocated to the rear to make room for turbo and cold air intake system.

Exhaust:   Going for a stainless 3" mandrel bent and lobster tail exhaust, possibly a high flow cat if new smog laws come into effect.. one or two resonators and a straight through muffler hanging off the rear. Car should be low enough to plumb exhaust under the diff and will need to section the gearbox crossmember so exhaust runs under it. I like a quiet exhaust and having a turbo also reduces noise somewhat compared to n/a so here's hoping a straight through exhaust will do the trick.

Cooling:  More custom bits.. alloy crossflow radiator + electric fans.   Air/air verticle flow intercooler sits in front of radiator where the original radiator was. Engine oil cooler off to one side of intercooler all tucked behind an unmodified front bumper (hopefully).. super sleeper styles. Front valence will likely need some mods for clearance. Will likely have a front lip to disguise things.

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