KE25 drivetrain plans


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  4agzte 20v in the build...  
The Plan : 20v 4age twincharger    

*20v silvertop block, std ae101 rods and pistons decompressed (forgies and rods to come later)
*20v blacktop head and quad throttles, check port matching
*custom water manifold off back of head (for firewall clearance)
*remote thermostat mounted under intake plenum behind S/C
*Metal head gasket or even O-ringing?
*Turbo, big compressor - small turbine, T3/TO4e or Garrett GT2870R GT3071 etc
*external 38mm wastegate maybe two of em?
*Steam pipe turbo exhaust manifold
*Front mount intercooler
*SC12 supercharger ex ae101 4agze, std bottom mount + custom top mount and tensioner, custom inlet/outlet manifolds
*alternator low mounted under turbo with custom tensioner to suit
*Control valve fitted dependant to type of system used
*ECU = considering Megasquirt or Link G3 (4D mapping suit quad throttles, ISC control etc)
*Crank angle sensor and twin coil DLI ignition using waste spark
*W57 gearbox w/ front shifter position (ta63/ra63/ma61)
*9" gze flywheel and 5puck ceramic h/d clutch (if it holds) otherwise twinplate + custom fly
*more saving moneys/ sell kidney

Note: The least cluttered way I can see to setup the twincharger is to have the sc12 non intercooled. (see twincharger page in tech section). the downside is obviously heated air at lower rpm.
There's many other ways of doing it, and the following looks to be the least intrusive. All piping is low in the engine bay which will keep engine bay clean looking.

Pro's
*unique and exotic
*best of both worlds...
* low end torque
* top end power
*no boost lag
*no parasitic drag at higher rpm
*can turn s/c off for fuel economy

Con's
*complicated
*extra expensive
*more things to go wrong
*more parts to wear out & maintain
*extra weight
*time/money to tune
*cramped engine bay
*later b/b turbos have minimal lag anyway

twincharger setup

Engine : 20V 4AGT(Z)E
Gearbox :
 W57 close ratio 5speed
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 one ripper engine. The plan is to use the 20v silvertop bottom which has the larger crank journals and bigger gudgeons (compared to bluetop bigport 16v 4age). A silvertop 20v bottom end is apparently pretty much the same as ae101 4agze but much cheaper to purchase.. so have scored one 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. Depending on funds.. new forged pistons will need to be bought to suit 5valve head, but in the mean time the std 20v pistons decompressed and run on 10psi or so to get things operational. 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 either an aftermarket Link/ Link+ ecu or Megasquirt which also gives me the option of installing dli 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.

Gearbox.. For Supra W box, either need to modify std bell housings, ie cut/weld the A series bolt pattern on the front of a km36 5k/G52 bellhousing, could make an adapter plate on the back of a t50 bellhousing or splash out on a custom bellhousing (Niteparts) to mount a W series alloy supra gearbox to keep things strong & reliable with another custom driveshaft and gearbox crossmember made up to suit. This then easily fits a 4agze/9" flywheel/clutch without contact.
2nd option is the std ae86/aa63/at141 22spline T50 which may hold up with a light tune/low boost. but with the idea of a 20v twin-charger which means there wont be any lag running a T3/T04E or similar, who knows what will eventually make it's way into this thing! whichever way it'll be strung, but FUN!

Fuel delivery:  Must add a surge tank to counter the fuel surge problem at anything less than a 1/4 tank.  Either make a baffled fuel pickup inside the tank or use an external lift pump feeding an anti-surge tank positioned beside the main tank.  From there a boot mounted high pressure pump feeds fuel to the high pressure fuel filter in the engine bay... which then feeds through the fuel rail, adjustable rising rate fpr and back into the surge tank.  The surge tank has an overflow line at the top to drain fuel back into the main tank.  A larger fuel delivery line and a fuel tank vent is also required.   The std fuel line is pretty good size for 4age n/a.  There are two types of factory fuel tank venting, one running from top of tank to front chassis rail which I have in the SR, the other from the fuel filler pipe to the rear chassis rail.  combining the two, i can run the tank vent as fuel return and filler vent as the tank vent woot.

Electronics: Wire in ecu. Alarm installed with super trick anti-theft devices. battery relocated to boot to make room for turbo and cold air intake system.

Exhaust:   Going for a stainless 2.1/2" or 3" mandrel bent exhaust, possibly a high flow cat if new smog laws come into affect, and a dumpy muffler hanging off the rear.  I like a quiet exhaust but having a turbo also reduces noise somewhat compared to n/a so here's hoping a straight through exhaust with resonators and cannon muffler will do the trick

Cooling:  3-core custom alloy radiator or something similar + electric fans.   Intercooler sits in front of radiator and oil cooler off to one side all tucked behind an unmodified bumper.. super sleeper styles. valence will need some mods for clearance unfortunately.

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