Thread: P76 4.4 into disco 3.9 auto

Try reading this for some answers. Leyland P76 - Wikipedia, the free encyclopedia

I would have thought the V8 block was the same but as for the other bits you'd better do some more research.

S

I have an idea the 4.4 is a physically bigger block, so there are some manifold misalignment issues.

And good luck hooking up all the pollution gear to make it legal.

Regards
Max P

And good luck hooking up all the pollution gear to make it legal....

all the pollution gear on the rover 3.9 seems to be connected to the inlet manifold. If that can be adapted to the 4.4, I don't see any issues

Originally Posted by procrastination inc

Many questions.

Will a P76 4.4 be a bolt in swap for a 3.9 rover motor?

Will a 3.9 manifold fit and will the standard injection system fuel it appropriately?

Is there a torque, HP improvement to be had?

Are there any reliability issues with the P76 engine?

Don't go there!

The P76 even the ones from the Leyland Terrier trucks were all made in the early to mid 1970s and were based on the weaker early Rover V8's. They have had a long time to develop cracks etc.

The main difference in the P76 block is that it is a longer stroke on the same angle "V" so the valley at the top is about 25mm wider.

It is an orphan so parts are unique to it. Mounts for the aircon etc are missing, extractors need to be specially made for the extra width.

There is no fuel injection manifold for it.

If you fit spacers to your 3.9 manifold you lift up the top by about 25mm which has bonnet clearance implications.

A better option is to fit the 4.6 crank into your 3.9 - others will explain the logistics about that.

And yes, I did have a P76 based engine in my Rangie - after the 4th example of an unreliable P76 based engine (average 40,000 Km/engine) I had a 4.6 retrofitted and could not have been happier with the long term result (currently at 150,000 Km on the 4.6)

Diana

Originally Posted by Lotz-A-Landies

Don't go there!

The P76 even the ones from the Leyland Terrier trucks were all made in the early to mid 1970s and were based on the weaker early Rover V8's. They have had a long time to develop cracks etc.

The main difference in the P76 block is that it is a longer stroke on the same angle "V" so the valley at the top is about 25mm wider.

It is an orphan so parts are unique to it. Mounts for the aircon etc are missing, extractors need to be specially made for the extra width.

There is no fuel injection manifold for it.

If you fit spacers to your 3.9 manifold you lift up the top by about 25mm which has bonnet clearance implications.

A better option is to fit the 4.6 crank into your 3.9 - others will explain the logistics about that.

And yes, I did have a P76 based engine in my Rangie - after the 4th example of an unreliable P76 based engine (average 40,000 Km/engine) I had a 4.6 retrofitted and could not have been happier with the long term result (currently at 150,000 Km on the 4.6)

Diana

Easy fix use the rover timing cover and heads off a rover block and then it it is a very slight modifacation to your air con brackets and power steer brackets

And yes you need spacers to be able to use your 3.9 fuel injection manifold and you can use all rover pollution gear

You can even use rover extractors you just need to bolt them up on a dummy block and use a chain to pull them in towards the block

As the block has a longer stroke everthing needs about 40 mm added

I doubt you would get any power gain maybe some extra torque

Anything is possible

cheers

sounds harder than I can be bothered with

As mentioned already you need the inlet manifold adaptors, but also require the adaptor to fit the auto, both are available through a place in Melbourne for less than $500 when I priced them before Xmas, there is a thread somewhere about this. You may also require an upgrade for the computer. I spoke to a couple of different places, one a LR specialist and the other and motor builder and tuner and neither were interested in fitting the P76 to my 3.9 rangie.

So I went ahead and rebuilt the 3.9 which end result is developing about the same power/torque that my P76 was putting out but I didn't have to go through the process of getting it engineered/blue plated.

Both me and my father used the same exhaust systems when we changed to P76 motors when we had 2 door rangies and he swapped it all to his curent 4 door.