Engine Replacement or Rebuild?

p m

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Apr 19, 2004
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La Jolla, CA
www.3rj.org
4.0 V8: 233 ft-lbs. @ 3000 rpm
300TDi: 195 ft-lbs. @ 1800 rpm

Factory data. What am I missing?
Here's a picture for you, taken from RPI Engineering website:
dynograph.gif

It shows 250 lb-ft for a stock 4.6 at 1500 rpm. I couldn't find a graph for a Land Rover 4.0, but given their similarities, let's take 15% off that number - and we arrive at 212 lb-ft. To check the scaling of 4.6 to 4.0 - the 85% of the 280 lb-ft (max torque close to 3k rpm) translates into 238 lb-ft, not too far off.

Here are your 300TDi power/torque curves:
https://www.automobile-catalog.com/wykres_power.php
 
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robertf

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Jan 22, 2006
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you can overlay them on that site
 

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xalty

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Oct 28, 2018
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Illinois
That R380 is not, nor the rest of the driveline, engineered or able to reliably deliver LS power. It's very expensive to do it right, and that's not it.
Meanwhile in Australia.... The original 4.8 and 5.3 LS truck motors are not very powerful, hell the Vortec 4200 I6 you mentioned is also in the same ballpark.
 
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ERover82

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Nov 26, 2011
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Darien Gap

ERover82

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Nov 26, 2011
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Meanwhile in Australia.... The original 4.8 and 5.3 LS truck motors are not very powerful, hell the Vortec 4200 I6 you mentioned is also in the same ballpark.

Old Rovers were for going anywhere, slowly.
 
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ERover82

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Nov 26, 2011
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lol @ swapping in a big six gas guzzler.

Select an engine swap that meets the following criteria:
Inexpensive
Simple to work on
Similar power to Rover V8
As good or better fuel efficiency
Reliable
Easy to source
Packaging fits LR engine bays
Bolts up to LR transmissions

Let us know what you’ve come up with.
 

discostew

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Sep 14, 2010
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Northern Illinois
I've had several responses from another posting also identifying the cats as a possible issue. My muffler is rusted out, so I might just replace the exhaust system completely and see if there's any change there first.
so your sure it's a bottom end knock because of info from a person who has never really heard the knock? And its either a catalytic converter or a bottom end knock ? Two noises that are very different from one another? If its a converter you will hear it rattle if you hit it with a soft mallet.
 

robertf

Well-known member
Jan 22, 2006
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Select an engine swap that meets the following criteria:
Inexpensive
Simple to work on
Similar power to Rover V8
As good or better fuel efficiency
Reliable
Easy to source
Packaging fits LR engine bays
Bolts up to LR transmissions

Let us know what you’ve come up with.

that engine doesnt bolt up to a v8 transmission. Hes using an adapter to the diesel bolt pattern, a repro short bellhousing, and placing the transfercase in the defender 200tdi spot, not the common spot shared with the v8 and 300tdi

There is also no way a siamese ported 60s engine with 20% more displacement gets the same or better fuel mileage.

there are shenanigans afoot
 

ERover82

Well-known member
Nov 26, 2011
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that engine doesnt bolt up to a v8 transmission. Hes using an adapter to the diesel bolt pattern, a repro short bellhousing, and placing the transfercase in the defender 200tdi spot, not the common spot shared with the v8 and 300tdi

There is also no way a siamese ported 60s engine with 20% more displacement gets the same or better fuel mileage.

there are shenanigans afoot

Yes, I am aware. I knew that one would confuse someone. There must be adapters available to mate with the transmission, otherwise it isn't inexpensive or feasible for most people. Again, I'm interested to hear suggestions.
 

pdXDisco97

Well-known member
Dec 6, 2011
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Oregon
so your sure it's a bottom end knock because of info from a person who has never really heard the knock? And its either a catalytic converter or a bottom end knock ? Two noises that are very different from one another? If its a converter you will hear it rattle if you hit it with a soft mallet.
No, I'm not sure of anything. But, the sound is pretty distinct from the cats. I figure that the exhaust, based on rusted out muffler, is overdue for a replacement, so I'm going to do that first. IF that doesn't solve my noise, I'll start digging into the engine, but at least I've got a new exhaust system either way.
 

Vegas99D1

Well-known member
May 5, 2009
187
9
Plano, TX
If cost isn't a concern, the LS conversion is an interesting thought. I was contemplating doing the same with my G4. But in the end, I stumbled upon a totaled truck with a freshly rebuilt motor. After selling off most of the good parts and the rest for scrap metal, I was about net even on the expenses.

If your going to do a rebuild, I'd consider doing a top-hat build on the block. Google Turner Engineering for the parts. Good people. I have a complete 4.6 rebuild kit in my garage. It was supposed to be for the G4. I'm hanging on to it for the next time the engine blows a liner.

Heres the website for future reference:

https://www.turnerengineering.co.uk/rover-40l-v8-46-v8-petrol-engine-parts-c102x3005626
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
If this is a XD then please don't do an LS conversion. There just isn't enough of these trucks to have people butchering them. If you do this I will make a voodoo doll in your likeness and do bad shit to it for a decade.
Are you interested in having this truck fixed professionally? Or would you consider selling it? I would do either for you and I have a shop near the state line of Illinois and Wisconson.