Maximum weight on kzj78 (1 Viewer)

[Cjryu92]

Hello everyone, first time posting so not sure if this is the correct section.

So I have a 1994 prado kzj78 and I'm building it up for an overlanding rig, my plan is to install a 2 in lift alongside with running 33 in tires. I was going to install rear drawers, rear steel bumper with swing door mounts and a front steel bumper with a winch. On top I was planning on mounting a flat rack with a roof top tent that'll weigh approximately 90ish kg with a 270 deg awning.

Is this all too much weight for the kzte motor? I don't want to strain it too bad to wear it out faster. I was also going to install a 3in exhaust with an intercooler and upgraded radiator to try and keep things cool.

I live in a remote area in central australia so reliability is a top priority.

Thanks!

 

[FJ40 that green thing]

I have the same rig and similar plans. You are talking about adding maybe 600-750 ish pounds, you are going to be fine. Go with the heaviest rated lift, don't overdo it on the tire size 32-33" max, if you build the drawer system, keep it light as possible and along with your additional cooling measures, you will notice it drives different but she will still pull as good as most 80 series at least.

 

[GTSSportCoupe]

Should be fine. Get rid of the EGR emissions system and butterfly in the throttle body also. These just choke the engine and exacerbate the turbo idi heat problems.

 

[Cjryu92]

Thank you so much! That's a pretty big relief, it gives me a lot more confidence to go ahead on the build. I'll definitely start with the motor and I'll start looking into that butterfly and EGR delete.

 

[FJ40 that green thing]

Just a follow up on this, I recently completed a 1,000 mile round trip for some mountain biking and offroading in Moab, UT in the 1996 KZJ78 with 1KZ-TE engine. The vehicle has a 2 1/2" Ironman lift, 33" General Mud Tires and a Dobinsons front bumper. I had myself and 3 kids. (450#) 4 bikes (120#) fridge, drawer system, food, gear, water, etc. (200#+) The KJZ78 did great on the road trip. Most comfortable cruising speed was between 70-75mph but I tested an approx 40 mile uphill stretch between echo reservoir and Evanston, WY and was able to maintain 80-85 mph the whole way (speed limit is 80mph). I know OP is in Australia so this location is meaningless for you. The 2800 RPM spot feels like its peak powerband and I was pleasantly surprised it still pulled so good up all those hills with the additional weight. All but the steepest grades going through big mountain passes from Price, Provo, Heber, Park City, Utah up to my home in Wyoming the vehicle was able to keep up with the flow of traffic. Obviously nothing like newer vehicles but nevertheless, very impressed with this wagon.

 

[AirheadNut]

That’s a far cry from my first LJ78! I took a trip with three other people, the whole back full of camping gear and 10 gallons of extra fuel in the roof rack. Cruising speed was between 55-65mph, and crossing the Continental Divide required running at less than 35mph with flashers on.

The new, re-powered LJ78 does much better; on the same pass with a RTT and a couple hundred pounds of cargo it could maintain an easy 55mph and get 5mpg better.

 

[Cjryu92]

Just a follow up on this, I recently completed a 1,000 mile round trip for some mountain biking and offroading in Moab, UT in the 1996 KZJ78 with 1KZ-TE engine. The vehicle has a 2 1/2" Ironman lift, 33" General Mud Tires and a Dobinsons front bumper. I had myself and 3 kids. (450#) 4 bikes (120#) fridge, drawer system, food, gear, water, etc. (200#+) The KJZ78 did great on the road trip. Most comfortable cruising speed was between 70-75mph but I tested an approx 40 mile uphill stretch between echo reservoir and Evanston, WY and was able to maintain 80-85 mph the whole way (speed limit is 80mph). I know OP is in Australia so this location is meaningless for you. The 2800 RPM spot feels like its peak powerband and I was pleasantly surprised it still pulled so good up all those hills with the additional weight. All but the steepest grades going through big mountain passes from Price, Provo, Heber, Park City, Utah up to my home in Wyoming the vehicle was able to keep up with the flow of traffic. Obviously nothing like newer vehicles but nevertheless, very impressed with this wagon.

View attachment 2981181

Thank you for this awesome data point. Sounds like you had a great time. This information is great and really gives me a lot of context. I am an American that will bring back the KZJ78 inevitably, the cruising speed around 80mph is surprising, I didn't realize it was that fast to be honest. You have given me a lot of confidence in terms of the capabilities of the KZ motor. I am planning a large winter (July) trip through the Simpson Desert here in Northern Territory/South Australia and it sounds like it'll do it with ease.

side note: Have you done the sound deadening mod to the interior? How did you fare in terms of road noise?

 

[FJ40 that green thing]

I haven't done any sound deadening mods mostly because I haven't found it necessary. The mud tires make some noise but its bearable.

 

[epaul]

It's just really important to install temp gauges (particularly EGT) and drive by them. I have a much lighter KZJ71 and don't carry much weight, and even with a 3" exhaust turbo back and a front mount intercooler, if I maintain 80mph up a steep enough grade, my EGTs and coolant can climb to dangerous territory. The 1KZ-TE has plenty of power and it can be hard to tell how hard you're working it without gauges. The factory temp gauge will not move from halfway until over 105C (220F), at which point you're already in trouble.

 

[wpwilder]

any insight on the 1HZ in the same scenario? 15 hr drive each way, RTT, camping gear in the back, and 3 adults?

 

[Gun Runner 5]

any insight on the 1HZ in the same scenario? 15 hr drive each way, RTT, camping gear in the back, and 3 adults?

Even with the 1HZ, I’d highly recommend a reliable EGT and water temp gauge. You would be shocked to see the EGT’s which of course directly effect water temps.

 

[wpwilder]

Even with the 1HZ, I’d highly recommend a reliable EGT and water temp gauge. You would be shocked to see the EGT’s which of course directly effect water temps.

i will definitely heed that advice. unfortunately, the trip starts tonight after work. anything i should keep an eye on without those gauges installed? i plan on taking it easy but there will be a lot of highway driving in the slow lane. PA to ME and back.

 

[AirheadNut]

Keep an eye on the factory water temp gauge; they don’t tend to move much unless the coolant gets quite hot but it will alert you to any large problems. Otherwise cruise where the engine feels comfortable, probably 100-110km/h, and keep an eye on the exhaust when pulling hills. If it starts to puff black smoke back off the throttle and downshift if possible. Higher rpm = more air = cooler EGT.

 

[Gun Runner 5]

i will definitely heed that advice. unfortunately, the trip starts tonight after work. anything i should keep an eye on without those gauges installed? i plan on taking it easy but there will be a lot of highway driving in the slow lane. PA to ME and back.

I responded to your p.m.

 

[SquirrelKZJ78]

Just a follow up on this, I recently completed a 1,000 mile round trip for some mountain biking and offroading in Moab, UT in the 1996 KZJ78 with 1KZ-TE engine. The vehicle has a 2 1/2" Ironman lift, 33" General Mud Tires and a Dobinsons front bumper. I had myself and 3 kids. (450#) 4 bikes (120#) fridge, drawer system, food, gear, water, etc. (200#+) The KJZ78 did great on the road trip. Most comfortable cruising speed was between 70-75mph but I tested an approx 40 mile uphill stretch between echo reservoir and Evanston, WY and was able to maintain 80-85 mph the whole way (speed limit is 80mph). I know OP is in Australia so this location is meaningless for you. The 2800 RPM spot feels like its peak powerband and I was pleasantly surprised it still pulled so good up all those hills with the additional weight. All but the steepest grades going through big mountain passes from Price, Provo, Heber, Park City, Utah up to my home in Wyoming the vehicle was able to keep up with the flow of traffic. Obviously nothing like newer vehicles but nevertheless, very impressed with this wagon.

View attachment 2981181

This post makes me want to drive my KZJ78 from VA to Yellowstone!

 

[AirheadNut]

This post makes me want to drive my KZJ78 from VA to Yellowstone!

If you do make sure to give me a shout! I live about 1.5hrs from the West Entrance.

 

[FJ40 that green thing]

This post makes me want to drive my KZJ78 from VA to Yellowstone!

do it..

 

[epaul]

drove my KZJ71 from nyc to Yellowstone last summer. Such a good time.

 

[FJ40 that green thing]

any insight on the 1HZ in the same scenario? 15 hr drive each way, RTT, camping gear in the back, and 3 adults?

I've never owned anything with the 1HZ but if it isn't turbo'd its gonna be slow. Certainly can handle the weight.