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Discussion Starter #1 (Edited)
Here is my diy project, i bought it as a stock car, went gte pistons and and forged rods NA-T, gtx4202, th400, 6k converter, e85, i eventually overpowered the stock ring lands, then replaced them with some CP pistons then cracked my main caps, as i needed a new block and crank i decided to buy an awd toyota crown from japan and get to work making my IS300 awd. The awd is still a work in progress but not too far off.
 

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Discussion Starter #4
Heres a few more, i keep things very understated, interior has ratchet shifter under manual trans boot and no gauges. Ecu takes care of vvti, fuel, ign, boost, flex fuel, and failsafes etc.
 

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Curious on why you didn't go with the AWD Altezza Gita swap, I would image that would have more parts that would correspond with the chassis rather than the Crown. I could be mistaken though. Really excited to see the outcome of this build.
 

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Very cool swap, just curious to see how it’ll hold up. None of the automatic 2JZ transmissions are particularly good and handling power and I can’t imagine that front diff is all that strong either. But still, really cool swap!
 

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Discussion Starter #12
Crown and Altezza use the same subframes so crown or gita is no differen except theres a million crowns worth fuck all and gita are very rare.
My front diff is a 7.2 inch and rear is an 8 inch, this is larger than gtr diffs (R160 and R200 FR) so i doubt i’ll have an issue. I am not using a toyota gearbox or transfer case, im using a full manual transbraked turbo 400 GM box i have adapted to take a new process np125 transfer case that usually resides behind an awd 4.0l turbo inline 6 barra engine in a 2.5 tonne suv.
 

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Discussion Starter #13 (Edited)
The chassis has none of the awd mounting points or bulges/recesses to accommodate the awd system, i have cut them out of my crown half cut and grafted them into my is300, this is not a bolt in job, it has a significant amount of fabrication required to make it work.
 

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Discussion Starter #14
Tunnel mod for front prop shaft, transfer case bulge will be fabricated from scratch rather than cut and shut from the half cut.
 

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Discussion Starter #15
My th400 is built for 1200hp, my torque converter is rated to 1200hp (6000rpm stall on the transbrake) and the transfer case is a 32/68 FR torque split chain drive unit, my rear diff is a plate type 200mm with a spring and shim upgrade the same as jzx etc use, i have had to stick with the 4.3:1 gearing of the crown due to the limited availability of different ratios for the front diff. This gearing should see it go close to 150mph over the quarter on 26 inch tyres with 8500rpm rev limit.
 

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Discussion Starter #17
I believe so, there are altezza gita wagons which are the same platform but 1st lexus IS300 sedan.
 

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Discussion Starter #18
Engine build- first round was gte oil pump, 625 head studs, brian crower valve springs, Spool pro drag i beam rods with 7/16 bolts, gte pistons, underdrive harmonic balancer, billet timing tensioner, 1400cc injectors, non return fuel system consisting of modded stock hanger and 320lph pump at 0psi into surge tank, dual 380lph staged pumps, hard lined to pressure reg with pressure transducer, single -8 teflon supply, splitting into dual -6 lines, one going through flex sensor into new fitting on stock fuel rail, other -6 line running into stock fuel rail supply, incl pulsation damper.
32psi from my 76mm turbo cracked the ring lands on the gte pistons so i bought a set of drop in CP pistons, this setup was pretty wild, that much power with a 6000rpm converter and limited tyre size resulted in significant wheelspin at 160kmh and above, i set up ign retard and cylinder cut traction control in my ecu but unfortunately the harmonics created by cutting intermittent cylinders at full power and rpm seems to have caused my to crack 5 of 7 of my main caps. These traction issues and the requirement of a new block and crank pretty much sealed the deal on the awd setup. Enter the crown halfcut.
This round of changes includes- all wheel drive as described in earlier posts, the awd 2jz is not interchangeable with a normal 2jz as the oil pump pickup comes out of the bottom of the pump rather than from the block halfway down. I gave the inlet and exhaust ports and bowls a light clean up and reshape, cc’d and polished the chambers, shimmed and fitted a set of brian crower 276/276 high lift cams, im reusing my piston/rod/fasteners combo from before in the crown block with new rings and bearings, i also use the NA gasket to maintain the tightest quench i can and pull it down tight with CA625+ head studs. I’ll be taking control of vvti now i have high lift cams, upping my fuel pressure to get a bit more headroom out of my injectors and seeing how much hp i can put down through all 4.
 

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Discussion Starter #19
Transmission and transfer case
transmission is a turbo hydromatic 3 speed automatic from a late 70s gm vehicle, all the usual th400 mods, 300m input shaft, extra clutches, full manual transbrake valve body, high rpm oil pump mod etc etc, the bellhousing has been cut off and a cnc adaptor bolted to the oil pump and an a340 J3 bellhousing bolted to that, i use a stock 1jz gte flex plate with arp flywheel bolts, i have a custom TCE 8 inch torque converter. It is th400 oil pump drive to toyota flex plate bolt spacing, its all the usual stuff, anti balloon, furnace brazed, mechanical diode, etc transbraked stall speed of 6000rpm and built to handle 1200hp, i had the th400 output shaft resplined to suit my transfer case, i made up a 10mm adaptor plate that is countersunk to the th400 and dowelled to the transfer case to stop and fretting from torque twisting things. The transfer case is a ~30/70 split, open planetary center diff, i will be using the lexus stability and traction control to brake the required wheel should wheelspin occur and redistribute torque to the wheels with traction the same as the more simple torque vectoring systems do. The front diff is a 7.2 inch reverse cut 4.3:1 open diff with an intermediate shaft going through the sump to a carrier on the opposite side and uses equal length acles left and right, my rear diff is a plate type lsd with a weir performance spring and shim kit installed in 4.3:1 ratio. Front and rear prop shafts have been remade with thick wall chrome moly steel tubing using the stock yokes, CV joints and center bearing. I also have BC coiloversin the rear and im looking at options for lower mounts to suit the front awd setup. I have a rear camber kit and hard race toe arms.
 

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Discussion Starter #20
Today i cut and shut my floor to make the front prop shaft tunnel section from the half cut fit. I cut it out of the halfcut along the seams that toyota spot welded by drilling out the spot welds, i used it as a template and marked my floor, then cut my floor with a 20mm overlap, i held it in place with tek screws, plug welded the holes, stitched the sheet metal inside and out, ground it back to clean it up and applied seam sealer and some matt black paint. Next week i will start on the transfer case bulge which will need to be made from scratch.
 

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