3.9 into defender???

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Regards the carb/EFi argument, just go with whatever you're happiest with.

Im better at injection than carbs and generally think it's the best option for mixing fuel with air, but then look at the amount of racing v8s on carbs, but I guess the dragster only makes max power, maybe EFi is better for midrange economy. So to speak.

The big bore engine is a fine machine you just got to keep fingers crossed all the time whereas at least with 3.5 you know the block is ok, even if they are seriously limited on power!
 
So, here's one for you all. I've got decided on the EFI. With all its pro's an con's I think its the best option with all things considered, especially the length of time I intend to keep the landy.

Here's the thing, I've got the chance of a 3.9efi disco with relatively low mileage as a donor, that I'd run for a while before I did the transplant. Only thing is, it's a Jap import. So, do you guys happen to know if there's any chance it'll be de-rated like many of the other high powered imports?

Any other differences/pitfalls with these would be a great help to know about also prior to purchasing.

Many thanks.
 
There are a few differences.

there will be two lambda sensors - one before the cat and one after.

the speedo will be in kmh

engine will likely be a high compression 36D(Jap fuel 102 Octane)

the instruction manual will be in japanese, as opposed to the uk items which are in gibberish.

depending how long it has been in the uk the chassis should be quite good as they don't salt the roads in japan.
 
Lol griffman that's funny :D

Would be a shame to crush am import body/chassis if its in good nick, and/or it will be worth good money for someone with a rotter!
 
griffman said:
There are a few differences.

there will be two lambda sensors - one before the cat and one after.

the speedo will be in kmh

engine will likely be a high compression 36D(Jap fuel 102 Octane)

the instruction manual will be in japanese, as opposed to the uk items which are in gibberish.

depending how long it has been in the uk the chassis should be quite good as they don't salt the roads in japan.
Click to expand...

:dance:

Was imported 2006. Its clean under but the rear arches are starting to go. Chassis clean. Im not too worried about any of that to be honest, but will make it good to sell on bits I guess.

So there's no real power difference?

Mr Noisy said:
Lol griffman that's funny :D

Would be a shame to crush am import body/chassis if its in good nick, and/or it will be worth good money for someone with a rotter!
Click to expand...

Yeh, if it comes to it I'll stick it up for parts in here, should be some good stuff on it.
 
The power the engine makes will depend on many factors as the ecu compensates the fuelling map to take various things into account - altitude, fuel RON, etc etc - the 3.9 Hotwire V8 was sold in various markets where fuel quality varies enormously - in the US standard unleaded is 87 or 91 RON whereas here it is 95, so there is no specific output per se as the ecu compensates.

You can maximise the potential of your engine by fitting a Tornado chip from Tornado systems.

This re-writes the fuel mapping, making it more economical so less fuel is wasted, and adjusts various other perameters as well.

You can then have a much more aggressive timing profile (30 degress BTDC at 4000 RPM with Vacuum pipe off is the setting) which makes the car much more perky and improves top-end power by a bit but has 15-20% torque gains in the low and mid range, which is what you want in a heavy vehicle.

Cost is 400 quid and worth every penny - you also have to make a few adjustments to the air flow meter but it is very straightforward.
 
noexitroad said:
you may need to put your exhaust manifolds off the 3.5 onto the 3.9. you may need to reroute your air intake as well
Click to expand...

Second that - the 3.9 manifolds and headers make the exhaust drop BELOW the chassis rails. I've chopped mine down but they are still a bit low - I wish I had gone with a 3.5 system when I had it all apart
 
MattMatt said:
Second that - the 3.9 manifolds and headers make the exhaust drop BELOW the chassis rails. I've chopped mine down but they are still a bit low - I wish I had gone with a 3.5 system when I had it all apart
Click to expand...

you could use the transmission crossmember off the disco which allows the 3.9 pipes to pass under it, but of course the 3.9 will have cats which is gay.
 
MattMatt said:
Second that - the 3.9 manifolds and headers make the exhaust drop BELOW the chassis rails. I've chopped mine down but they are still a bit low - I wish I had gone with a 3.5 system when I had it all apart
Click to expand...

Mr Noisy said:
you could use the transmission crossmember off the disco which allows the 3.9 pipes to pass under it, but of course the 3.9 will have cats which is gay.
Click to expand...

Ok then, cheers for that, its a heads up before I get to regretting it, but what should I do with the lambda sensors if I fit my old 3.5 manifolds and downers?:confused:


.
 
18 stoner said:
Ok then, cheers for that, its a heads up before I get to regretting it, but what should I do with the lambda sensors if I fit my old 3.5 manifolds and downers?:confused:


.
Click to expand...

As far as i know remove them and fit a non cat tune resistor?

Think that will do them job cos the ECU no longer looks for sensors.
 
Yep, cheers for that bud, Ive been doing a bit with the ole search button and found out quite a bit.

Seems I need a 470ohm resistor sticking in and that'll do it. Even found out where its situated and it could easily be a green one too!

Cheers for all the pointers guys, and if anyone else in the future reads this and wants to see the links Ive "searched", here they are;

http://www.landyzone.co.uk/lz/f42/power-loss-misfire-petrol-heamorage-116321.html

http://www.landyzone.co.uk/lz/f42/tune-resistor-173012.html

Fuel injection

.
 
Bit of a refresh On this thread, due to family circumstances I didn't get much further than the last post on this thread.

Now, with a new spur of enthusiasm I'm wanting to crack on with the transplant.

One thing that has happened though, is over the months I've started fancying the carb option instead of the (trouble for me) installation of an ecu.

I know there's pros and cons to the efi vs carb argument, but I'm wondering what you guys think to an offer I have.

Basically, I have the chance of a refurbed holley 390 down draught carb at just £175. I will need a manifold too, but as this project seems to be strung out over a long time, I can sure wait another few weeks until I find one for sure.

So, in general, what do you guys think to this as an option for me, and how suitable this carb would be for my 3.9?
 
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