TB42 vs TD42

I'm just asking out of curiosity; a few people have mentioned that the TD42 engine is more grunty than the TB42, but looking at the specs, the petrol put out 129kw @ 4000rpm vs the diesel 85kw @ 4000rpm and the petrol produces 330Nm @ 3200rpm vs diesel 264Nm @ 3200 rpm. So the petrol would seem to produce significantly more power and torque at the same rpm than the diesel. Only the 4.2 diesel turbo (GU) puts out the same torque but at lower revs. Is this the one that's being refered to as 'more grunty'?

On paper the TB42 has it all over the naturally aspirated TD42, and the on road performance reflects those figures. Put them in low range and it's a different story. The TB42 is good, but the TD42 is better. The big diesel just keeps pulling down low, down to below idle. The big petrol will stall or need clutch slip (talking manuals here) in these circumstances. Put a turbo on the diesel and the 4.2 petrol is left well behind in almost all situations, especially if the boost is wound up a bit.

Also, 129kw TB42 was the EFI version, the earlier carby TB was 125kw.

Tony

I've not driven the diesel, but sounds like there's more torque early on and it's a much flatter curve, perhaps the petrol peaks higher, but isn't so broad a rev range. I found it interesting though that the petrol and diesel have the same bore and stroke. Usually associate longer stroke with a diesel to get the compression. How do they have the same stroke but different compression ratios?

Diesel has smaller combustion chambers.

Tony

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Originally Posted by YNOT

Put a turbo on the diesel and the 4.2 petrol is left well behind in almost all situations, especially if the boost is wound up a bit.

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Fair call, I agree totally but just to keep the playing field level... spend a similar amount of $ to the "Turbo" money for the TD on the Petty option by putting reduction gears on an Auto TB42 and now the Petty is back in front in almost all situations.

I REALLY loved my TB42 GQ... 2nd best Patrol, indeed 2nd best 4X4 I've ever had. It was my first Auto and initially I couldn't drive it for sh1t but once I got my head around the Auto tranny it was a very very good 4X and my missus and daughter would have a crack at anything in it.

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Originally Posted by the evil twin

Fair call, I agree totally but just to keep the playing field level... spend a similar amount of $ to the "Turbo" money for the TD on the Petty option by putting reduction gears on an Auto TB42 and now the Petty is back in front in almost all situations.

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Except fuel consumption and range.

But I do agree, the price difference between buying a TD (and fitting a turbo) and a TB (and fitting reduction gears) is too big to ignore.

Tony

how about fitting a turbo to the petrol, that's gotta give it some kick! (and even worse fuel consumption).

Last years Outback Challenge was won by a GQ Patrol with a turbo TB48 petrol. I have not seen any power figures for it but I would estimate some where between 500 and 600 hp.

Tony

DX grunt - 4.2 TDi - says it all :thumbup:. lol

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Originally Posted by DX grunt

DX grunt - 4.2 TDi - says it all :thumbup:. lol

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pretty much the ultimate for torque!

Why do a simple question of whats better between two engines does the mention of snails get thrown in the equation ???

My GQ is the TB42 EFI Auto
100% stock nissan and it has enuf power to do everything i need
Heaps power , pulls large loads up hills
Only donwside is the economy (or lack off)
But its 3 tonne ,aerodynamics of a brick coupled with an auto
Wasnt certainly bought cause it economic thats for sure

Diesel Vs Petrol
Personal choice

I'm just asking out of curiosity; a few people have mentioned that the TD42 engine is more grunty than the TB42, but looking at the specs, the petrol put out 129kw @ 4000rpm vs the diesel 85kw @ 4000rpm and the petrol produces 330Nm @ 3200rpm vs diesel 264Nm @ 3200 rpm. So the petrol would seem to produce significantly more power and torque at the same rpm than the diesel. Only the 4.2 diesel turbo (GU) puts out the same torque but at lower revs. Is this the one that's being refered to as 'more grunty'?


The original question did mention turbo's, and you know how easily we get side tracked!

Tony

Yep
We have ways of making you "Torque"

Id certainly be interested in a seat of the pants 4.2 TD GU Vs GQ TB42 comparison

And we all no figures on paper dont mean much in the real world

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Originally Posted by MQ MAD

Yep
We have ways of making you "Torque"

Id certainly be interested in a seat of the pants 4.2 TD GU Vs GQ TB42 comparison

And we all no figures on paper dont mean much in the real world

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You are exactly right about figures on paper not meaning much. On paper the GQ TD42 naturally aspirated motor and GQ RD28T have very similar power and torque figures, but driving them reveals them to be completely different.

Tony

I always thought one drove a TD42 and towed an RD28T

Waha waha waha
Thats absolutely gold !!!!!


Seriously the RD28Ts are alrite
They beat walkin i suppose
But i reckon if ya stepped up to maybe a brisk walk
Well thats different

My TB42E has extractors and 2.5 inch exhaust , i have fitted 4.375 ratio and run 265/75/16 tyres

The lower ratio has certainly woken the big behemouth up a bit , it almost takes off a standing start like a V6 Commo and loves to rev through the gears , more torque is felt through the rev range and is heaps responsive its better for towing , on inclines , headwnds , offroad 4wding and better engine braking on declines

It does not use any more fuel than before with the 3.9 ratio as it doesnt labor as much as before and only revs approx 250-300rpm more on the highway in overdrive with torque convertor locked , still get 400-420 highway km from 88litres LPG

I love it on the highway when overtaking , manually kick it down to 3rd and floor it and she just revs and pulls away .
Also with the 4.375 ratio it makes the extractors and larger exhaust do their job a lot earlier rather than waiting for the revs to build up with the lazy 3.9's

hi guys... i have td42 diesel with my nissan patrol at the moment. the reason diesel make lots of noise. my friend ask me to swap my td42 with his tb42 carburetor.. so do you guys think it will be worthy to swap with him... plz let me know.. i will highly appreciate you guys valuable advice... i m just confused which 1 better tb42 or td42 thanks

Pretty much all the differences have been listed above. It really comes down to personal choice and the type of driving you do. You should just have a drive of both and feel any differences for yourself. Some people swap but moast are happy with what they have. I got a petrol with auto because thats what i wanted when i was looking for a patrol. I am happy with it:)

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Originally Posted by Pitbull

My TB42E has extractors and 2.5 inch exhaust , i have fitted 4.375 ratio and run 265/75/16 tyres

The lower ratio has certainly woken the big behemouth up a bit , it almost takes off a standing start like a V6 Commo and loves to rev through the gears , more torque is felt through the rev range and is heaps responsive its better for towing , on inclines , headwnds , offroad 4wding and better engine braking on declines

It does not use any more fuel than before with the 3.9 ratio as it doesnt labor as much as before and only revs approx 250-300rpm more on the highway in overdrive with torque convertor locked , still get 400-420 highway km from 88litres LPG

I love it on the highway when overtaking , manually kick it down to 3rd and floor it and she just revs and pulls away .
Also with the 4.375 ratio it makes the extractors and larger exhaust do their job a lot earlier rather than waiting for the revs to build up with the lazy 3.9's

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Hey mate what was rough cost of changing the diff gears?

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Originally Posted by taslucas

Pretty much all the differences have been listed above. It really comes down to personal choice and the type of driving you do. You should just have a drive of both and feel any differences for yourself. Some people swap but moast are happy with what they have. I got a petrol with auto because thats what i wanted when i was looking for a patrol. I am happy with it:)

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Thanks taslucas

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Originally Posted by Toha

hi guys... i have td42 diesel with my nissan patrol at the moment. the reason diesel make lots of noise. my friend ask me to swap my td42 with his tb42 carburetor.. so do you guys think it will be worthy to swap with him... plz let me know.. i will highly appreciate you guys valuable advice... i m just confused which 1 better tb42 or td42 thanks

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I love my diesel and would not convert to the tb42

I have had more then a few tb42 rd28 and now td42 turbo
Tb42's were ok had a few and the rd28 with more boost and fuel made the td42 non turbo feel like a slug as they like to rev and power comes on higher in the rev range..
Before fitting the turbo to the td42 i was quite dissapointed with it even with winding the fuel up a little but now it is great and gets on average 500 k's to a $100 fuel around town.

I have to say my rd28 performs quite well, climbs things offroad that a mates n/a td42 cannot and beats tb42's on road. The only downside is getting off the line with a heavy trailer and 35's on.

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Originally Posted by gqt

I have to say my rd28 performs quite well, climbs things offroad that a mates n/a td42 cannot and beats tb42's on road. The only downside is getting off the line with a heavy trailer and 35's on.

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Good little engine but it must have been a real sick tb42 that you beat on road.



Tap, crackle, pop

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Originally Posted by taslucas

Good little engine but it must have been a real sick tb42 that you beat on road.



Tap, crackle, pop

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Totally agree
After having an RD28T GU and now owning a TB42 GQ
It would want to be 1 serious RD28T to see even the taillights on the TB42
Empty or towing
My TB42 has it all over my old RD28T

I know it sounded healthy, but it was slow as. Mate of mine said his gotta introduce me to one of his mates that has a stock tb42 shorty that's ment to move along quite well. My fuel is wound up quite alot, can leave it in 5th on hills that needed 3rd when I first bought it.

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Originally Posted by growlers71gq

I love my diesel and would not convert to the tb42

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yeap even i dont have problem with td42.. only reason asking i get embarassed with the huge noise of td42... it will be helpfull... is there any way of reduce the noise thanks

thats right

Which noise do you mean?


Tap this.........

Hope your mates swapping it for a tb and about 3000 cash. Not really a fair trade a td for a tb. On the subject tho it really is personal choice, for me all my 4wd will always be diesel the torque is just amazing then add a turbo and a few mods and it turns into a monster off road. Not saying this isnt possible for a petrol but how the two engines deliver the power and how they produce it is very different. As for the noise you are referring to i have no idea, the TD42 isnt a noisy engine as long as you keep rockers adjusted and its in a good condition.

Personally I think only a turbo'd TD comes close to standard TB anywhere on or off road as far as performance goes. Even then the average turbo TD is still only line ball with a standard TB.
Only area of note for the diesel would be engine braking, stupidly deep water and long distance touring, TB had plenty of low down torque for all conditions off road IMO. And then had the top end power to really get things moving :)

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Originally Posted by Chris79

And then had the top end power to really get things moving :)

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My TB is sooooo much fun on a gravel road......nothing like 4 wheel drifting 2.5 tonnes of vehicle.....
That said a turboed TD42 probably is a better all round long term ownership proposition. The torque, fuel economy etc. but coming straight from road cars the TB suits my driving style.


Tap this.........