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Discussion Starter #1
Hey Guys,
I am in the planning stages for a 4bt swap into a aussie GQ Patrol, I did a quick measure of the engine bay and looks like plenty of room, my main concern is whether i can achieve a comfortable cruise speed of around 110kmh(Our legal top highway speed (68.75 Mph) My plan consists of the following:

*120 hp 4bt

*Nissan FS5R50A with
1st 4.55
2nd 2.62
3rd 1.52
4th 1.1
5th 0.83 ratios

*3.9 diffs
*35 inch tyres

I used a couple of online calculators and get around 2150 rpm at 110k (68.75) and 1950 rpm at 100k (62.5 Mph our non highway top speed)

My questions are does anyone have similar gearing and will the motor economically sit on 2150 rpm on long touring trips? is this conversion worthwhile, currently it has a 4.2 litre petrol (gasoline) which gets about 16 Mpg:(

It should weigh in the vicinity of 5700lbs fully set up with barwork, winch, spares etc and two people.

Any help would be greatly appreciated :beer::beer: cheers from Oz
 

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Welcome to the forum, your gearing isn' perfect but I think it will be OK. Speed kills mileage and will have a greater effect than the gearing. I switched from mud tyres to A/Ts and gained 10% in mpg. How are you planning on using the Nissan gbox, are you making the adapter plate? please take and post plenty of pics as they will be useful. good luck

Gaza
 

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Discussion Starter #3
Welcome to the forum, your gearing isn' perfect but I think it will be OK. Speed kills mileage and will have a greater effect than the gearing. I switched from mud tyres to A/Ts and gained 10% in mpg. How are you planning on using the Nissan gbox, are you making the adapter plate? please take and post plenty of pics as they will be useful. good luck

Gaza
Hey Gaza, We have a couple of places here who do a chev pattern bellhousing to the the nissan gearbox (fingers crossed, still investigating). cheers
 

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The Buildup Thread section is set up to be a documentary photo history of an INPROGRESS or COMPLETED diesel conversion project. Note what it says in the information block on the Buildups page. All PLANNING stage projects seeking input should be placed in the General Discussion Forum for more exposure of questions on how to accomplish certain tasks and overcome obstacles.

Moved to the General Discussion Forum.
 

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Try this calculator, it is nice for setting all of the different variables.
http://www.grimmjeeper.com/gears.html

I personally like this calculator.
I inserted your numbers and it come out at 2020 rpm at 65mph (5th gear). probably perfect. :)


In your 4bt I would also install a 3200 gov spring kit over the stock 2600-2800 gov. It just makes life much better for shifting and top end.
 

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My Scout (4300 lbs) with the aerodynamics of a brick gets 23 mpg at 70-75 mph mph turning over 2000 rpm with mud tyres. That extra 150 rpm (and added wind resistance) cost 6 mpg.
If your intentions are get the most fuel milage out of your vehicle, you want to set your cruise rpm above 1700 (peak torque) and below 1900 rpm. After 2000rpm the Injection Pump goes into the performance mode and fuel consumption goes up.
 

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Nice to see another Patrol owner. I'm trying to fit a 4BD2T into my '63 L60.

Curious as to why you aren't going with a Nissan diesel. They would probably me setup already with little or no modifications needed.

Tripper
 

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Discussion Starter #11
Nice to see another Patrol owner. I'm trying to fit a 4BD2T into my '63 L60.

Curious as to why you aren't going with a Nissan diesel. They would probably me setup already with little or no modifications needed.

Tripper
Hey mate, looking into this conversion as a td42t here is around 4-5000 and the 4bt i can have for around 4000, i also want a low reving, torquey, and long lasting motor, also fed up with nissan motors, had two of the petrol tb42 crack heads, and want something different:)
 

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callum421

im thinkin about the exact same conversion. ive found the 120hp 4bt for $3500 so yeah heaps better off than fixin the poxy rd28t.
would love to know what you know im just starting out. i have the tools a knowledge to build a adapter plate just dont know the bolt patterns and stuff yet. what redline do they have. im a rev head and ive been tryin to find a motor that is a similar rev range as the original as to be able to achieve the same cruisin speeds. im also wondering if you know much about the 6bt do you recon it would fit. my other thought is something common rail would be nice. but yeah any info you know so far would be great. ill let you know what i find out as i get more details. i know one crew that does a full kit to fit them to landcruisers, i dont know if thats any help to us yet. ill keep you posted.
 

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Interesting info on the Nissan engine. I stumbled on my Isuzu for about $500 which included the whole front clip. You might want to look that direction as well and it is a tad smaller than the Cummins. Both appear to be great options however I went with what I found first.

If you follow through, make sure you do a build thread as that would be a pretty unique end result.

Tripper
 

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I am reading lots of posts about swaps into Patrols but non of this threads shows that it was really done :(

Ben
 

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I know of at least 1 Patrol here with a 6BT, have not had a chance to inspect it. If 6 will fit then a 4 will have extra room.
 
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