TB42S (Carb) aftermarket EFI options

[jakeslouw]

@jakeslouw
I have thought about the RD28, the experiences I hear from people is very 50/50 when it comes to reliability. The argument is often said, if you are thinking of going RD28, why not just go TD42. I think there is generally more support both aftermarket and oem for the TD engines, as well as a knowledge base and community support. Nothing against the RD, just doesn't seem right to for me.
What's the support locally for the RD? (not say the TD's or TB's is good, I just can't imagine the RD being great).

The RD28 was a factory fit on the Patrols. These days, most older spares are imported anyway, as Nissan ZA is useless and over priced. So you can get most of what you need from eBay Australia.

The RD28 is available from importers at under R20k. The TD42 is almost unobtainable these days as far as I know, and if the importers do have them, well north of R45k per engine the last I got prices.

Here are the last prices I got from my local guy:

"TD42/TD42T we do not stock these at all.
TD27/TD27T non turbo is R23000 and turbo is R25000
QD32/QD32T we only have the non turbo engine for R29000
RD28/RD28T RD28 non turbo only for R17500"

The QD32 and RD28 are turbo-ready with oil squirters. If I remember properly, Reenen fitted a set of TD27 turbo manifolds to a QD32. The RD28 turbo manifolds are available from Jap Auto if I recall.
The RD28 is a direct inject overhead cam engine that revs like a petrol: the TD42 is an indirect injection engine with push-rods like the TB42 and suffers from combustion chamber cracks and ultimately, catastrophic head failure.

[symmetry4wd]

Look at petrus 4.5 gq ....works well

I must go visit him some time and check it out actually...

[symmetry4wd]

Current engine started life in a GQ, thus normally-aspirated but it was the vaunted "silvertop" so the pistons were turbo-ready and there are oil squirters in the block. Engine had over 400k km on, but the pistons, crank and bearings were still good. I did have to re-sleeve it and replace the head.

It is fitted with the turbo from the altitude-compensated bakkie but with the EGR blanked off and the wastegate linkage disconnected. I also later replaced the fuel pump with an 11mm one (standard is 10mm), but to be honest that made little difference on this little turbo. Max boost is just less than 1 Bar. It was dyno'd once (when it still had the 10mm pump) at 410Nm and 103kW at the wheels.

Comparing the TD42 with the TB42:
at very low revs (anything under 1200), the TB has more torque. I don't know how much because I have never seen a dyno result that starts under 1500rpm, but I don't think it's a huge amount. However, the diesel's fuel pump has a built-in mechanism that strives to keep the revs steady at idle. As a result, it can seem as if the diesel has more torque, because you can usually just leave the throttle alone and the car will crawl over most obstacles, whereas the TB has to be driven almost all the time. So off road, there are pros and cons to both, but in terms of ultimate ability the TB wins for me. I also found the Nikki carb to be very tolerant of angles and seldom had any trouble re-starting after a stall.

On the road the TD is a very clear winner. At 120 it is running pretty much at maximum torque, and that torque is enough that one very seldom needs to gear down. I can do hills in 5th that I used to have to gear down to 3rd. And economy is better.

Having said all that though, the TB48 is a very strong contender. A bit less torque but more power and similar fuel consumption than the TD, and no turbo to nurse. The only disadvantage to me is that one needs an aftermarket management system. I am a bit allergic to those having seen too many expire in wet conditions but if enough care is taken they can be very reliable. However that would also be necessary if you injected the TB42.

Very interesting comparison between the TD and TB, thanks.
I do find that I constantly need to keep the TB42 "alive" and very steep/engine braking descents, and on steep crawls, it won't just crawl over obstacle or type of resistance just by itself with no throttle input.

I really need to get my Nikki tuned by an old carb guru, mine runs well, but is currently only "tuned" by me, which isn't saying much as my knowledge and tools are limited.

Regarding injecting the TB42, If I imported and found all the necessary components off of a TB42 EFI and swapped them onto mine, I could mount the ECU wherever I like, out of harms way.
But if I go with the aftermarket EFI systems, the self learning ECU's are located on the throttle body unit itself, meaning it would be in the engine bay where the throttle body/carb would be, which isn't ideal for any wet/water crossing situations. I wonder how well sealed the ECU's are in these aftermarket EFI systems.....

[symmetry4wd]

@jakeslouw
I have thought about the RD28, the experiences I hear from people is very 50/50 when it comes to reliability. The argument is often said, if you are thinking of going RD28, why not just go TD42. I think there is generally more support both aftermarket and oem for the TD engines, as well as a knowledge base and community support. Nothing against the RD, just doesn't seem right to for me.
What's the support locally for the RD? (not say the TD's or TB's is good, I just can't imagine the RD being great).

The RD28 was a factory fit on the Patrols. These days, most older spares are imported anyway, as Nissan ZA is useless and over priced. So you can get most of what you need from eBay Australia.

The RD28 is available from importers at under R20k. The TD42 is almost unobtainable these days as far as I know, and if the importers do have them, well north of R45k per engine the last I got prices.

Here are the last prices I got from my local guy:

"TD42/TD42T we do not stock these at all.
TD27/TD27T non turbo is R23000 and turbo is R25000
QD32/QD32T we only have the non turbo engine for R29000
RD28/RD28T RD28 non turbo only for R17500"

The QD32 and RD28 are turbo-ready with oil squirters. If I remember properly, Reenen fitted a set of TD27 turbo manifolds to a QD32. The RD28 turbo manifolds are available from Jap Auto if I recall.
The RD28 is a direct inject overhead cam engine that revs like a petrol: the TD42 is an indirect injection engine with push-rods like the TB42 and suffers from combustion chamber cracks and ultimately, catastrophic head failure.

Did we get the RD28T/Factory Turbos locally? and did we get the RD28's in our Patrols locally? I know overseas, but would like to know about locally.

Are there any mechanical differences between the RD28 NA and turbo? When you say the RD28 NA is turbo ready, are the internals the same between the turbo and non turbo, are the compression ratios the same? Fuel system?
Were there any mechanical injection RD28T's or were all the turbo variants electronic injection?
What are your guys thoughts on the RD28's reliability?

[Peter Connan]

Quite often the problem is not the ECU itself (although if that gets water it's obviously tickets), but all the various sensor connections.

As for RD28's in local cars: I have never seen one. Did see one in a grey import, and heard about a couple of others.
A friend of my wife's told me he owned a shorty GQ back in the 90's which had a 4-cylinder diesel engine, but he didn't know which engine or where the car had come from.
I have wheeled with many guys with 3L GU's. The autos are OK but the manuals struggle in the rocks. On the road they are great. More fuel efficient than any of the TB options, and enough torque at cruising speed.

[jakeslouw]

Did we get the RD28T/Factory Turbos locally? and did we get the RD28's in our Patrols locally? I know overseas, but would like to know about locally.

None locally. Nissan ZA was weird that way. I think there was even an SD33T that we didn't get either.

Are there any mechanical differences between the RD28 NA and turbo? When you say the RD28 NA is turbo ready, are the internals the same between the turbo and non turbo, are the compression ratios the same? Fuel system?
Were there any mechanical injection RD28T's or were all the turbo variants electronic injection?
What are your guys thoughts on the RD28's reliability?

Now that would stretch my memory too far. As far as I know, the RD28 NA was mechanical, as well as the RD28T. The RD28ET was electronic injection with a very simple control system that used minimal sensors: I think basically a crank position sensor, a very simple airflow meter and a boost pressure sensor. Compression ratios should have been the same on all models.

[symmetry4wd]

@peter connan

Earlier in the thread, you mentioned that maybe a GU is a better platform for me, and in a lot of ways that may be true, mechanically...
I was driving my GQ earlier, and i'm absolutely in love with it, I got out to go collect something and when I turned around to look at it, it just struck me as my ideal 4x4.

Nothing against GU owners or their cars, and I hope this is taken offensively,
I just think the square, muscular, bulging arches, and lines of a GQ are just perfect for me, I also like a more simple or "basic" vehicle. The GU is much more generic SUV/Wagon/4x4 in my opinion, at least unmodified.
All just my opinion.

With that in mind, i'm still interested if anyone has any ideas on fuel injecting a TB42 Carb.
How many guys on the forum with a TB42 EFI, only ever heard of a handful in the country?

[symmetry4wd]

Maybe @peter connan can answer this, or if anyone else has an idea

What would be needed to run the TB42 Carb distributer with an EFI system? not something I'm all that clued up on...

[Peter Connan]

I don't think that is possible.

It would be easier and better (though probably not cheaper) to create a crank position sensor setup in the bell housing using index marks on the flywheel.

[mvcoller]

Nothing against GU owners or their cars, and I hope this is taken offensively,
I just think the square, muscular, bulging arches, and lines of a GQ are just perfect for me, I also like a more simple or "basic" vehicle. The GU is much more generic SUV/Wagon/4x4 in my opinion, at least unmodified.
All just my opinion.
With that in mind, i'm still interested if anyone has any ideas on fuel injecting a TB42 Carb.
How many guys on the forum with a TB42 EFI, only ever heard of a handful in the country?

I have had both types, a 1995 GQ and I currently own two GU Y61s.

I really love the shape of the GQ, that square rugged look really makes it look what I think a real 4x4 shape should be (nearly like the old Nissan X-Trail macho square look vs the Jelly Bean lookalike new shape X-Trail).

A GQ with 10J rims and at least 33" tyres and a 3 inch lift is a stunner and looks wise, it is hard to beat, in my book at least!! (See pictures of mine). Mine could really intimidate Taxis and windgat youngsters in their pocket rockets, particularly after I fitted the Lexus V8 motor.

My biggest gripe with the GQ is the dash, console and middle row of seats.

I just don't like the whole dash-console setup. Its layout is yugh!!, and there is not much one can do to make it better. The window switches are all wrong there, as are the radio and tape-deck positions; low down it is hard to reach if you're belted into your seat and you have to take your eyes totally off the road for 5 to 10 seconds to see what you are doing, selecting a station.

The door cards of the GQ is also a total non-event, and the front ones is as much worth as tits on a tiger......

I also prefer a double din radio, my GQ had a radio and separate tape deck, a very messy layout. I much prefer the position of the GU/Y61 radio position higher up, you hardly have to take your eyes off the road to see what is happening on the dial. On the Series 4 Y61 the radio is already a double din, and on the earlier ones, it is easy to modify the dash to take one.

The middle row of seats are a real problem, you sit far too low, either the seat is too low or the floor is too high. I made 40mm spacers the lift the seats, but it was a mission to lift the clips that hold the seat in the normal seating position. The 40mm lift was still fairly uncomfortable for my two 6ft 3 in tall sons, as their heads were only about 10mm from the roof lining.

Not many people leave rear-most seats in the Patrols, I have them out in GU 3.0 GL (came without them) and left them in the GQ 4.5 GRX. I like the way the 6th and 7th seat bench folded forward in the GQ, the seats in my two GYs fold up to the side the same as the Fortuner does. It wastes too much space when folded. up.

I also prefer the total rugged strong looking front bumper replacements you get for the GUs, I have never seen a decent looking comparable replacement bumper on the GQs, they all look like a normal front bumper with cow-catching hoops.

As far as the TB42i is concerned, my Patrol had factory injection (it was a grey import from the UK with a MPH speedo, which was a problem). I do not know if it improved matters, apart from being reliable and working properly on steep inclines where a carb may have its chambers running dry. It was not at all light on fuel, on a Namib trip I got an average 2.23km per lt on the section from Solitaire through the Namib Spergebiet to Walvis. I was lucky to get 6km/lt on the open road. This despite me doing a MAUS conversion, including a chip to try and improving consumption.

Eventually I fitted a 149lt main tank from Northern Off Road and a 60lt secondary tank of my own design built by Uys van Rooyen of Stofpad 4x4. In total I could put 210lt of fuel in the system, which in 2011/12 cost me over R2500 to fill!!! This gave me a decent range between fill-ups....