Newer Hiace V8 Conversions

[JZH]

Hi, I'm the owner of a 2013 Hiace H200 van (3.0 turbo diesel, pic below) and I'm trying to determine if a V8 engine swap is feasible. Why? Because I like my (almost unique, in Europe) van, but I don't like diesels and I don't like slow vehicles of any kind. (There's also the issue of the London Ultra-Low Emission Zone expanding to where I live in 2021, and diesels are bad, Bad, BAD...)



Many years ago I put a Chevy V8 into my Porsche 914, so it's not like I'm a total newbie at this, but that was also a very long time ago and I don't really want to spend several years working on this one.

I've been searching for some time, but all I've found so far is information about earlier versions of the Hiace van (pre-2005). My engine bay looks fairly similar to the earlier models, but I'm not really interested in trying something that everyone else has already declared to be "impossible". It is strange, though, that this chassis has been around for almost 15 years now, and there are so few V8 conversions? I've seen a short video of the one DKM Fabrication in NZ did some years ago (1UZ-FE), but I'm sure I don't quite have their level of fabrication skills.

Any information on H200 Hiace V8 engine conversions/swaps would be much appreciated!

Cheers,

JZH
London, UK

 

[JZH]

Okay, not much interest; fair enough, it is a van...

I was wondering if I'd have to fit a modern engine in order to be exempt from the London ULEZ, but I've tentatively determined that the age of the engine won't make any difference, as TfL will simply look at the DVLA V5C and assume that a 2013 vehicle would have met 2013 emissions standards (there are no emissions data on the V5C, probably because this was an import). So long as I have previously notified the DVLA that the engine capacity and fuel type have changed, they should make those changes to the V5C and I'll be home-free.

So, I'm pretty sure that I can fit a 1UZ-FE engine, which should be easier to source and install anyway.

I also need to work out which transmission I will need, as I've got an old-school live rear axle at the back.

Any thoughts on the best 1UZ engine to use?

Cheers,

JZH
London, UK

 

[gloverman]

Id be using a 1uz vvti or a 3uz. Easiest way is aftermarket ecu so you can stick with dbw pedal. Intake out the front helps with pipework to air filter. Rear sump required so 3uz is a good choice. My headers even fit them even though its tight. Manual box use r350 from same model. I have bellhousings in stock so thats easy for me. If running auto then stock Lexus box but its back to stock management. If auto I would most like go for a lhd 1uz then run the loom into the compartment behind the drivers seat. Or i make a whole new loom.

 

[JZH]

Thanks, mate. I can see that I have a lot to learn about Lexus V8s...

I have found a short video of an H200 Hiace with a non-vvti 1UZ-FE engine (

):



That's the same body style and engine compartment as I have, so at least I know it fits!

You mentioned going for a 3UZ, however, which has a front intake and a rear sump. I don't plan on hot-rodding the engine, so a bit more power in stock form would be fine with me. The baseline engine has 106kW and 300Nm, so any Lexus V8 would be a substantial improvement.

I do want to use an automatic transmission, however, partly because the van is used on the highway/motorway most of the time, but also because I thought it would be simpler to do, but that may just be wishful thinking!

I understand that I will need an auto trans with a standard yoke, given the Hiace's live rear axle/differential, and that most Lexus V8 models have independent rear suspensions, so won't work. I see that Toyota 4x2 trucks seem to have the right transmissions, but they were only mated to 2UZ engines. And Crown Majestys, but those are quite rare. The tranmission issue could be a real obstacle to doing this conversion "right".

Can transmission tail shafts and housings be swapped? I.e., can I buy a knackered Tundra V8 trans from the 'States and swap the necessary parts onto a matched (rear-sump) 3UZ engine/trans purchased in the UK as a complete kit? That would solve a lot of problems...

Cheers,

JZH
London, UK

 

[gloverman]

Who told you you can't use the Lexus Box? Ive used heaps with the correct driveshaft setup. That way the wiring works.

 

[Zuffen]

The engine in the photo is from an SC400/Soarer.

That engine has a rear sump and slip yoke transmission so double good news.

I would use the engine, transmission and ECU from the Soarer/SC400 as it would make it a pretty easy swap.

This way you're not buying custom parts to mate to a manual. The parts would be flywheel, clutch, bellhousing. A few pound in that list that disappears with the stock auto.

The downside of that engine is the hydraulic cooling fan but easy to get around with a mechanical fan bracket off an LS400.

 

[gloverman]

Rod soarer dont have slip joint trans. The slip joint units are only on the 131 crown.

 

[JZH]

Who told you you can't use the Lexus Box? Ive used heaps with the correct driveshaft setup. That way the wiring works.

Sorry, I may have got the wrong end of the stick, but I was reading the 1UZFE Q&A I found on this Website:

"There are two basic auto trans fitted to the 1UZFE. One type is fitted to LS40/SC400s and the other is fitted to Crowns. The Crown type has a standard yoke; the others have a rubber donut. The bad news is the tail portion of the trans is significantly different between the two output methods. If you are going to use a live rear end you must use a Crown transmission, as it is the only one that has a yoke that slides in and out to cater for varying driveshaft length. The donuts are good only for independent set ups."

I'd be happy to use a Lexus transmission, but there seem to be very few of them with the slip joint tail shaft available in the UK. That's why I was asking about swapping just the tail shaft and housing from a 4x2 Tundra, which, based on US eBay trawling, appear to have the same type of rear diff as the Crown and my Hiace. Buying the parts from Toyota/Lexus would also be an option, but not one I'd really want to pursue!

Found a s/h tail housing (no shaft), but it appears to be off a (non-vvti) 2002 2UZ 4.7l Tundra:



Rod, I don't know if the existing Hiace radiator and fans would cope with the V8. But I should check if the radiator/fan set-up is hydraulic already.

Cheers,

JZH
London, UK

 

[gloverman]

You dont need a slip joint trans. I adapt flange ones all the time using a 4x4 style slip joint in the driveshaft.

 

[Zuffen]

Kelvin,

I forgot about the Soarer having a donut. I parted one out about 15 years ago.

Use and different radiator.

Measure up and see what you can find. I run a Range Rover Classic radiator and it didn't break a sweat when I had the supercharged engine hooked up to it. For if you current fans fit whatever radiator you use use them. Air is air and as long as they cover enough of the radiator they should be fine.

 

[JZH]

You dont need a slip joint trans. I adapt flange ones all the time using a 4x4 style slip joint in the driveshaft.

Well, that changes the calculation quite a bit! Do you have a picture of this? It doesn't sound like it would be terribly expensive...

If I don't have to worry about the tranmission tail shaft I can simply concentrate on finding a complete, rear-sump engine/trans in good nick and go from there. Awesome!

Cheers,

JZH
London, UK

 

[JZH]

Here are some undercar shots of the current diesel/auto setup:





I don't know how thick the crossmember is, but I think I will defeinitely need a rear-sump engine...

 

[gloverman]

my files are too big to put photos here but I put some up on my facebook page

https://www.facebook.com/TheCartune...gt5uAkFoeZUngQjfchs7FJnavbDUXTP52eElOpvnR3VKN

 

[JZH]

Thanks, mate. I saw the pictures of the H200 Hiace with 3UZ engine. I can see that the front intake should work a lot better than the side intake on the earlier engines.

Any issues with the immobiliser on the 3UZ? I think I can find someone here who can mod the ECU if necessary.

I'm looking for any non-LS 3UZ (for the rear-ish sump), I guess?

Cheers,

JZH

 

[gloverman]

 

[gloverman]

I do both 1uz VVti and 3uz immo off.

 

[George_R]

I can help with immobilizer and 3uz ecu reprogramming (emissions off, remap, speed limit off, conversion to m/t if requred)

As well as signal converter for instr. panel and a/c system

 

[JZH]

Hi George.

I've been quiet for a little while as I deal with other "life" matters, but I am still thinking about how to best accomplish this conversion. Thank you for your offer!

You seem to be one of the experts on Lexus ECUs, so maybe you can help me understand which version/year of 3UZ engine I should be looking for?

I do want to use an automatic trans, and either the 5-speed or the 6-speed would seem to be usable. I think I would prefer the 6-speed, as it appears that the shifter mechanism might fit into the Hiace's dash-mount shifter housing better than the (longer) 5-speed shifter. Of course, neither might fit at all, but I'm hoping to retain a strict OEM look if I can.



1. If I understand how the immobiliser works, if I wanted to use the immobiliser function I would need to have the ECU, the wiring harness, the key(s) and the receiver (and maybe the lock cylinder itself), all of which is unlikely to be available unless I bought the entire car (or maybe got a front cut). Hence, the practical necessity of having someone like you remove the immobiliser function from the ECU...

2. How does cruise control work on these cars? Is it something I can enable via the ECU? The van currently does not have any form of cruise control, so I would need to add a control stalk in any case.

3. As it is a van, I don't think I really need to remove the speed limiter, but it's nice to know it is possible to do so. The current speedo reads up to 180kph or so, which is not especially high, but there is room for a bit of additional needle sweep.

4. I would definitely like to keep the OEM instrument panel, but there are some differences I wonder how to deal with: the existing (diesel) tachometer only goes up to 6,000 rpm and redlines at 4,200rpm, whereas the V8 will rev higher than that. The gear selection lights show P-R-N-D-3-2-L (it is a 4-speed auto box).

5. I also need to keep the existing A/C system. It has a pretty simple manual control, however, with no digital climate control aspects:



Given the above requirements, is there any other reason to choose a 5-speed trans? From what I've seen the change from 5-speed to 6-speed happened in different years for the different models, so the LS430 changing in 2004, he SC430 in 2006 and the GS430 in 2005 (the timing may have depeneded on the market in which the car was sold). Newer would probably be better, unless there is a reason why the newer ECUs cannot easily be used. Thanks for your help.

Cheers,

JZH

 

[George_R]

Hi!
If you're not overloading it, 6 spd is the way to go. Wideband knock sensors, newer ecu, 2x overdrive gears
I'd recommend to remove immobilizer, without too many details for now
Cruise control: just needs additional analogue speed signal, and control stalk which is basically a bunch of switches and resistors in one enclosure. No big deal. System status is transmitted to instr.panel digitally.
Climate control: idle up + a/c mag.clutch request signal is digital

 

[JZH]

Excellent, thanks. It sounds like the 6-speed is the way to go. I will start looking for a complete engine/transmission, and also the 6-speed's shifter and (I think I will also need) an ECT switch for the dash.

I've determined that the Hiace is only a little heavier (~125 lbs) than the LS430, so its performance with the V8 and 6-speed transmission should be similar (0-60mph in a little over 6 seconds).

Once I get the engine, I presume I can send the ECU to you for the mods?

Cheers,

JZH