3.9 into 4.2 will it go !

serpentine belted ones are better as have improved water pump that supplies both baks equally unlike earlier

As far as I'm aware, if you use a serp front end, the whole lot will bolt together fine, but the keyway in the crankshaft nose will not be long enough to provide a positive drive to the front pulley, so although it will be sandwiched tight, it will be turned by friction alone.

As for the camshaft fight, I'm with vougese39.

is the knackered 4.2 engine a serp or v groove engine?

landroverlane said:

is the knackered 4.2 engine a serp or v groove engine?

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hi its a v groove engine thanks

Just a thought when i build up a 4.2 using a 3.9 block it won't need a different ecu will it
the way i see it it should run ok and on lpg. All i have done is unbolted to the side the inlet manifold injectors still in situe ? advice please

Just to clear up any confusion, a vee belt is about 10mm wide and has one 'V' and a serpentine belt is wide and flat with lots of 'V's on the underside.

Just making sure that were all singing off the same hymm sheet

If the only component that is 'new' to the vehicle is the block, then all will be ok. and it will still be a 4.2

Many thank the hunt is still on . the spanners have been sharpened.

craykent said:

Just a thought when i build up a 4.2 using a 3.9 block it won't need a different ecu will it
the way i see it it should run ok and on lpg. All i have done is unbolted to the side the inlet manifold injectors still in situe ? advice please

Click to expand...

The question was asked on page2, but no answer unfortunately.
I'm guessing if using the injector set up with the 14CUX system it will be the same?.......but hope someone will confirm this for you

good luck with the changeover

all that you are changing during this conversion is the block. everything else is going to be the original parts. you already have the 4.2 ecu, wiring loom etc. what you are doing with the 3.9 block (using 4.2 internals) is going to turn it into a 4.2. you should not need to change any electrics or settings. the only real difference between the two engines is the stroke, mabe cam and possibly the ecu map (not sure if they even bothered). the whole injector set up and the injectors are exactly the same. i would suggest if it is a v groove engine to keep it that way for ease of assembly!

14 cux for al its faults will adapt fitted to any engine capacity rover v8.
examples
fitting as a replacement to a failed 3.5 flapper system ok
3.9 - 4.2 conversion fine
3.9 4.6 conversion fine as a temp but you will need a altered mapped chip as the fuel demand is greater but will run

That answers the question many thanks