[JOE D'ESKIMO]

Hi has anyone done a 16a motor and 5 spd gearbox from a vitara into a sierra, Just wondering if this type of conversion is a stright forward conversion or is there still a problem or modifications needed. i have a complete running vitara as a donner car.

[fordem]

I believe it's a fairly common swap and the norm is to swap the motor and keep the original Sierra gearbox through the use of an adapter plate, specifically to avoid complications with the rest of the driveline.

The Vitara has the transfer case attached to the back of the gearbox and uses a rear axle with the pumpkin in the center, the Sierra uses a divorced transfer case and the rear axle has the pumpkin offset.

It's fairly straight forward when done using the Sierra driveline, provided the G16a is carbureted - kits are available - if the G16a is fuel injected, it's a more complex swap.

[rexhunta]

Also from memory you need to bash out the transmission tunnel as the vitara boxes are slightly wider then the sierra case.

[Gwagensteve]

I don't your mechanical skills so I can't determine if you'd find this a straightforward conversion, but it has been done.

The G16a conversion was common before it was superseded by the G16B as the most common/desirable conversion. Whilst the G16A has more torque the the G13, it is a longer stroke motor so it doesn't rev as freely and lack throttle response compared to the G13. G16A's are now difficult to find as they were last produced in 1995 and they are prone to cracking the block above the starter motor. make sure the engine you have is in good condition or you could struggle to find another one.

The engine will bolt in with the driver's side engine mount moved rearwards 20mm. You might be able to retain the Vitara sump, otherwise you'll need to swap in the Sierra sump and oil pickup which will need to be welded as it's a different diameter and isn't a straight swap.

If you retain the Vitara carby, the Sierra carb hat doesn't swap over as the carb it a different throat diameter. Bonnet clearance as also at a premium due to the G16 being taller.

Other than that, it's basically wiring etc. You'll want to swap to a bypass heater tap as Vitaras don't run a heater valve at all and coolant flow is important.

Using the vitara gearbox is uncommon, generally, an adapter plate is used to bolt on the Sierra 5 speed. using the vitara transmission will require you to widen the tunnel near the front seat bolts, remove the vitara transfer case, fit a shortened jackshaft, and fabricate a new gearbox crossmember. The advantage is a relatively common and stronger gearbox that allows the use of the larger vitara clutch and flywheel. The disadvantage is the added work, there's more "custom" things under the car to go wrong, and the underside of the car ends up looking like a dog's breakfast - the vitara manual wasn't designed to have the transfer removed and that results in a gaping hole on the back of the gearbox with the output shaft inside it. It's sealed, but it's messy and screams "conversion"

It's not feasible or desirable to use the Vitara transfer case.

[Dec]

I completed a 16a conversion back in my old SJ80 keeping the Sierra gearbox by using the BenT Adapter kit. I also used the original carby off the g13. My memory of replacing the engine is pretty blurry now but you can see few pics in my old build thread if you'd like.
viewtopic.php?f=4&t=33311&hilit=Dec&start=30

[JOE D'ESKIMO]

Hi all thanks for the input and advise. its a g16a carbie motor. as i would need to buy a sierra 5 spd and then a conversion/adaptor kit as well as a 1.3 fly wheel and cluth to make it all work, i'm thiking to convert the vitara diff to leaf springs and that way i could leave the vitara gearbox & transfer case intact. may need to shorten the rear tailshaft?