110 County engine upgrade

[Mustlust]

After 30 years of service it's time to find a bit more power. Having started to refine highway behaviour by changing the hi-range gearing in the lt95, I'm looking at replacing the 3.5 v8 with either a 3.9 or 4.0 engine from a disco.
Question: can I keep the intake manifold and carbie from the 3.5 and use it with my electronic ignition system on the upgrade. I was hoping to keep a fairly original looking engine bay and want to avoid the efi wiring.
Interested in ideas before I get serious about finding a donor.
Thanks

[justinc]

Certainly can maintain the natural county engine bay look with even a 5.2 upgrade....��.

Make sure that you get/ build an engine with high compression (your 3.5 has 9.35:1) and even more importantly that the carb needles get changed to suit engine capacity. You will be amazed at how much torque an SU fed engine can produce when they are set up right!!!
My pick would be a post 2002 4litre d2 or a 1999 on p38a 4.6 as they are 9.23:1 compression ratio.

Jc

[123rover50]

The best upgrade to a 3.9 is ....... Isuzu:cool:
I put a second hand truck engine in mine back in the 80,s and its never given any trouble. Best thing I ever did.
But then I am a bit deaf:(

Good luck.
Keith

[debruiser]

The best upgrade to a 3.9 is ....... Isuzu:cool:
I put a second hand truck engine in mine back in the 80,s and its never given any trouble. Best thing I ever did.
But then I am a bit deaf:(

Good luck.
Keith

I drove Bearman's 3.9 Isuzu county and it's no louder than my 2013 D90. I would love a 3.9 Isuzu....

Sorry Mustlust, I don't have anymore than that :(

[Phil B]

The best upgrade to a 3.9 is ....... Isuzu:cool:
I put a second hand truck engine in mine back in the 80,s and its never given any trouble. Best thing I ever did.
But then I am a bit deaf:(

Good luck.
Keith


AFM (through Grey's) auctioned off several 4BD1 (n/a and t) motors this week.
May be worth bidding next time.

[Mustlust]

While the diesel is clearly an excellent motor, I'm trying to keep costs down and having sunk $ into the elec ignition system and carbie overhaul, trying to stay on the good side of the wife.
Will keep an eye out for a later model donk....and the attempt to rebuild. Last engine I rebuilt was a Renault 12 nearly 30 years ago when the engine died the day after I finished uni. How hard can it be to marry an early intake manifold to a later block?

[Mustlust]

Q: why a high compression engine? What's the difference?
Would a 3.5 rebuild be ok, if budget limits my options?

[bee utey]

The 3.5 is the most reliable version of the land Rover V8, because the block is that much thicker around the smaller cylinders. So for a rebuild on a budget, I'd stick to the basics and redo your own motor. Rings, bearings, a quality towing camshaft and timing chain should set it up for another 300,000km. The bigger capacity motors, especially the low compression ones, are as thirsty as hell and not that much more powerful (excepting the 4.6 of course). Best of all is that you can do most of the work with the engine block still installed, unless you have a badly leaking rear crank seal.

If you do end up finding a later engine in excellent condition for not much, all your accessories will fit with minor modifications only, some of the bolt holes in the block and heads did change over the years.

High compression is an advantage in Australia as our fuels are generally good quality, low compression motors were introduced for world markets where fuel quality was poor, and also for emissions reasons. Which don't really matter unless you live and commute into the inner city with it. :)

[Mustlust]

Found a cheap D2 engine with a liner problem that could make for a possible project build. Can the serpentine belt pulleys be taken off and replaced with my original v belt auxillary items? Would also put on original intake manifold. Does this work?

[bee utey]

Found a cheap D2 engine with a liner problem that could make for a possible project build. Can the serpentine belt pulleys be taken off and replaced with my original v belt auxillary items? Would also put on original intake manifold. Does this work?
To fit one of the 4.0/4.6 family engines, you will need to replace the camshaft in any case, it has to drive your distributor which the late engine doesn't have, and use your sump, front cover, oil pickup, inlet manifold etc. You also need a spacer behind the front pulley bolt as the crank is slightly longer. I wouldn't bother unless you found a 4.6, as "top hat" (flanged) liner replacement will set you back $thousands. A 3.9 on the other hand has the correct cam but suffers from a lack of block strength just like the 4.0/4.6.

[Mustlust]

Hmmmmm, the old 3.5 is looking like it could be the way to go then. More straight forward job. The motor has 140km's and starting to get pretty tired, made worse by the fact I live on a steep hill. New rings, bearings, cam and chain should do it, I hope😋

[lebanon]

I opted for the 4.2 and kept the SU carbs. It made a huge difference and the engine bay still looks the same.

[justinc]

I opted for the 4.2 and kept the SU carbs. It made a huge difference and the engine bay still looks the same.

Unfortunately for us we didn't get that engine here 😣😣.

Jc

[FV1601]

Maybe keep it simple? Get a price on the essentials to freshen up the 3.5. Admittedly it is 20 years since I did mine ('76 R/R), but I was surprised at how cheap and easy it was. As Bee Utey says, the work was all done with motor in situ; a better camshaft and headers/exhaust had made a big difference a couple of years earlier. Best of all was that glorious sound, still miss that...
Rich.

[Mustlust]

Just a shame the front output shaft leaks like a sieve, otherwise would do it in situ. At least I can give the engine bay a tidy up while its out.
Any recommendations re cam? I know this topic has been done, and done again, but people don't often mention how the cam performed after the install.

[manofaus]

Just a word of warning. If you change your engine for a later model you need to comply with the emission regs for that engine. I know nothing of the differences between all the engines. But in the eyes of the plod it is a defect not to comply explicitly to the smog rules of the engine. You can go forward in years but not back too.

[PAT303]

Certainly can maintain the natural county engine bay look with even a 5.2 upgrade....��.

Make sure that you get/ build an engine with high compression (your 3.5 has 9.35:1) and even more importantly that the carb needles get changed to suit engine capacity. You will be amazed at how much torque an SU fed engine can produce when they are set up right!!!
My pick would be a post 2002 4litre d2 or a 1999 on p38a 4.6 as they are 9.23:1 compression ratio.

Jc

JC,do 110's still have the restrictor plate under the carbs?,that was the first thing you threw away with the stage one V8's when looking for power. Pat

[PAT303]

Hmmmmm, the old 3.5 is looking like it could be the way to go then. More straight forward job. The motor has 140km's and starting to get pretty tired, made worse by the fact I live on a steep hill. New rings, bearings, cam and chain should do it, I hope😋

If your motor feels sluggish I'd say your cam is worn,it's a common thing with that motor,the cam doesn't get enough oil,once the heat treatment is worn through the wear accelerates and the motor couldn't pull the skin off burnt milk. Pat

[justinc]

JC,do 110's still have the restrictor plate under the carbs?,that was the first thing you threw away with the stage one V8's when looking for power. Pat

Hi pat no thank goodness with the arrival of disc brakes to the front of the county and slightly more efficient wipers the restrictors were a thing of the past...☺

Jc

[Mustlust]

How well do the heads travel after 140 000 k's? Do they usually require attention? Is this another thing to factor into the budget?
I will be chatting with the local engine reco bloke tomorrow and aim to get a $ figure for a clean, bore check and hone and tidy up of the crank.
Is there anything else he needs to look at?
I think I can handle all other work.
In reading older threads, it seems the TR Spares has a cam for pre-pollution gear for the RRC 3.5, with mild torque gains and good for hwy. will have to call them for more info.

[PAT303]

On Rover V8's the two things that wear the most are the cam and big ends,at 140k the heads will be fine. Pat

[jimr1]

Just a shame the front output shaft leaks like a sieve, otherwise would do it in situ. At least I can give the engine bay a tidy up while its out.
Any recommendations re cam? I know this topic has been done, and done again, but people don't often mention how the cam performed after the install.
When I rebuilt my 3.5 lt I put a stage 2 Crow camshaft in ! They make a big difference , and help produce more power . Work nice in mid to upper range !!..Jim :)

[Mustlust]

Just driven 700 kms with new RRC hi-range transfer gear into the lt95 and man what an improvement. This would have to be one of the best modifications for a std 110 v8 county!
Thanks Jimr1, I will look into the Crow cams over the break. Keen to get into this rebuild as soon as I'm home.