yaris motor swap

[Typrus]

Ok, coming back from another haitus.

TDI motor. 1Z generation (96, 97 Passats, some Golfs and Jettas)
1.9L I-4 SOHC 8v configuration, intermeshing intake and exhaust manifolds on the rear of the engine in the installed format. Transmission on drivers side. Clockwise rotation.
This engine has similar physical dimensions to a 3AC.
I took all measurements, for ease, with all accessories and such taken into account. Widest to widest, etc. Bottom of pan to tallest point. Front of crank to back of engine, unless noted.
1Z motor- ~28" tall, ~29" wide, ~20" deep, ~34" deep including transmission
3AC motor- ~25~ tall, ~30" wide, ~ 24" deep.

So, either is bigger in one regard.

Now for factory power specs-
1Z- 90HP @ 4000RPM, 150ft/lb @ 1900RPM
3AC- 62HP@ 5200RPM, 75ft/lb@ 2800RPM


With double the torque, you run into the issue of- even if an adapter plate were used, the T4wd tranny would grenade itself. Unless only the utmost extreme of caution was used. Any driveline shock, at torque, would pop it.

Advantages?
1996 VW Passat Sedan, 5 Speed manual 1Z-TDI Roughly 2890lb curb weight- My personal experience is, based on driver, 40-47mpg and impressive torque. Now, we just had a Stage 3 Turbo kit installed, with an updated computer, bigger injector nozzles, chip, and bigger turbo. It still gets 40-47mpg and it GETS. I speculate 250 ft/lb of torque. We'll soon be getting a turbo-back new exhaust (upgrading .5" in diameter, higher flow cat and muffler) and expect better power and economy at that point. It has about 270,000 miles on it and still runs cherry. Door handles and window regulators suck though. Typical VW.
Did I mention it GETS?
On a trip to South Dakota, 4 people in the car and clothes for all 4 for a week, we averaged 43mpg going 85mph up through Wyoming. The way back we averaged 42. As it turned out, both back brakes were dragging the whole way. Never had to fight to keep 85mph.

1984 Toyota Tercel 4wd Wagon 6-speed 3AC 2490lb curb weight. I experienced between 16 and 45mpg. I could consistently get 45mpg doing 85mph between Colorado Springs and Fort Collins, both ways. Based on 6 trips and filling just before and after. My car was probably a freak. That, and I didn't leave stock well enough alone lol. Typical to-and-from town mileage (I live about 15 miles from town) averaged between 26 and 32mpg. With just me in the car, and maybe a duffel bag with clothes for 5 days, I could maintain 85mph all the way to and from Colorado Springs on I-25. Put even one person in the car and I'd struggle in spots, she'd fall back to 80 or so. 4 passengers and some luggage and 75 was it, milking it at 60mph on some hills.

So, we have a 400lb weight advantage on the Passat. Aerodynamics, not so much. Dock one for the flying shoebox.

So, consider the revs at speed.
If you could make the 6-speed work (look into Cryogenic heat tempering) then would the revs fall into a reasonable range to cruise on todays highways? (typically 85mph) I don't remember the Tercel's revs at 85 in my 84 (taller gears) but the Passat is somewhere above 3k if I remember right. Maybe even as high as 3.5k. You would want revs to fall roughly in this area, or even lower (but no lower than say 2750RPM, else the engine will be lugging hard to enough to offset the fuel savings by decreased revs)

If somehow possible, engineering a limited for the 6-speeds front diff would be best. Stressing the drivetrain to break traction on 2 tires is actually easier on it than shocking it to break one tire, then the massive shock of that tire grabbing traction.


Due to the 1Z containing its lift pump in the injection pump, an in-tank pump would not be necessary, however a low-pressure "booster" pump would be advantageous (Carter makes a sweet rotary pump, rated for gas but I know folks using it in their TDI's) Bonus.
Rotating the 1Z to be longitudinal places the intake and exhaust manifolds on the passenger side. Bonus.

Installed width limitations are also a consideration. Consider that the turbo is hardmounted to the exhaust manifold.



So why a 1Z? The simple wastegate turbo architecture makes for easier setup. Everything else is essentially the same as an ALH (the later model)

Advantages to an ALH? Variable-Vane Turbo technology (boost faster) stronger pistons and connecting rods and an extra 5lb of torque. And easier to source.
Good option? Get an ALH engine, and swap for the 1Z manifolds. I believe they will directly fit. Thus, more simple architecture with a stronger bottom end.

Custom mounting is always to be considered. Also consider that the TDI is installed at a slight slant from the factory. This may cause clearance issues in longitudinal format, or it may not. Hard to say.


You'd be trading bulletproof engine for bulletproof engine. Outcome? Better economy AND power.

[toastyjosh]

hey thanks for the reply that was very informative, the main reason I am interested in the tdi is mpg, but the large torque gain may be an issue. So yea Ithink adapting the motor to trans would be a trick trying to fab some adaptor or something. well thanks again for the awsome info.