4.6 v8 into '85 County 110

[clive22]

My '85 County currently has the original 3.5L V8 dual fuel T85 five speed - has since new. Runs OK when its running, but is very unreliable, seems mainly age related: tired old engine components.

Numerous worm components: carbs - from the gas, electric probs, weeping gaskets, down on power, etc.

Leaning heavily twoards putting Triumph Rover Spares 4.6 Long motor in, and running on straight petrol (dumping current gas tank too much space) for simplicity and so hopefully reliability. Fuel will hurt, but only really use for trips 10K kms a year so can live with.

I know a new(er) one should be considered, but have lots of stuff to be transferred over and the chassis is well maintained. e.g. Thomas PTO winch, McNamara Axles, Diff Locks, Maxi Ball, drilled swivels, Koni Long travel shocks, new brakes, long range tanks, etc,

Has anyone done this on this model, what probs will I face. E.g. bellhousing, air cleaner, radiator hose location. etc.

This seems like the best way to go but that at face value and the their may be details, etc. that make this the wrong choice and maybe their is a better one.

Have thought a 4.6 for extra low down power and ability to hold gear up hills


Any comments or experiences that anyone has would be appreciated

Clive

[RoverP6B]

Hello Clive,

I have a 4.6 running in my Rover P6B which originally had a 3.5 litre engine.

In both cases I am running twin SU carburettors, with the 4.6 delivering not only 50% more torque but also better fuel economy. I see 10.5 litres / 100km normally, with a best of 9.7 litres / 100km.

I had no problem in bolting my 3 speed transmission to the 4.6, the bolt holes are all still in the same place as my 3.5 which was cast some 30 years earlier.

The 4.6 will totally transform your 110,..you won't be disappointed.:)

Ron.

[DeeJay]

I put a 4.2 litre motor from an LSE Range Rover in my '85 County, a great combo. The mob that did it could have put in a 4.6 but I was'nt towing anything & they recommended this motor.
There are reports the 4.6 is a bit "lumpy" & I would have thought a 4.0 with the electronics would have plenty of oomph.
PM sent.
BTW I offered to help out when you drowned your engine up Healesville way & never heard back. Did you get it all sorted?

[PhilipA]

Just remember that the 4.6 block will only be part of the expense if you are replacing an old dying 3.5 block.

You should have the timing cover/oil pump rebuilt to ensure oil pressure,assuming you use the old setup.
The heads will need a rebuild, including new rocker shafts, rockers, pushrods etc. Lots of money.
The dizzy will need a rebuild.
Carbys will need to be rebuilt.
It could add up to thousands.

IMHO the cheapest way to do it would be to buy a complete low mileage 3.9 dressed engine which would include heads etc, and have the upgrade oil pump etc, if from a late S1 Disco. AFAIK the bellhousing will bolt up no problem. The only problem should be with the routing of the top radiator hose, a minor detail. Also you will have to improvise wiring to the alternator etc. You may also be able to get some money for the injection.
make sure that any engine is complete with Alternator , PS pump, starter etc etc as these things are expensive.
Regards Philip A

[lokka]

Just remember that the 4.6 block will only be part of the expense if you are replacing an old dying 3.5 block.

You should have the timing cover/oil pump rebuilt to ensure oil pressure,assuming you use the old setup.
The heads will need a rebuild, including new rocker shafts, rockers, pushrods etc. Lots of money.
The dizzy will need a rebuild.
Carbys will need to be rebuilt.
It could add up to thousands.

IMHO the cheapest way to do it would be to buy a complete low mileage 3.9 dressed engine which would include heads etc, and have the upgrade oil pump etc, if from a late S1 Disco. AFAIK the bellhousing will bolt up no problem. The only problem should be with the routing of the top radiator hose, a minor detail. Also you will have to improvise wiring to the alternator etc. You may also be able to get some money for the injection.
make sure that any engine is complete with Alternator , PS pump, starter etc etc as these things are expensive.
Regards Philip A

Yep id go the 3.9 from a late 95 on S1 disco and run the EFI as well and keep it on LPG :D

[DeeJay]

Just remember that the 4.6 block will only be part of the expense if you are replacing an old dying 3.5 block.

You should have the timing cover/oil pump rebuilt to ensure oil pressure,assuming you use the old setup.
The heads will need a rebuild, including new rocker shafts, rockers, pushrods etc. Lots of money.
The dizzy will need a rebuild.
Carbys will need to be rebuilt.
It could add up to thousands.

IMHO the cheapest way to do it would be to buy a complete low mileage 3.9 dressed engine which would include heads etc, and have the upgrade oil pump etc, if from a late S1 Disco. AFAIK the bellhousing will bolt up no problem. The only problem should be with the routing of the top radiator hose, a minor detail. Also you will have to improvise wiring to the alternator etc. You may also be able to get some money for the injection.
make sure that any engine is complete with Alternator , PS pump, starter etc etc as these things are expensive.
Regards Philip A

Also, from memory, you would need to put a larger Dia exhaust system to get the most out of the 4.6

[dickyjoe]

Go the 4.6

There's no substitute for cubic inches!

It will rock

[Traco]

The long stroke 4.6 will produce more low down torque which is what's needed for a heavy 4x4. The 3.9 is smoother due to its bore/stroke ratio and can be tuned, and is ideally suited to something like an MGB. Also, importantly, you should really get a 4.6 block with top hat liners already installed, which I believe the TRS short engines have.

[PhilipA]

Of course if money is no object :- Go the 4.6 .
A $10,000 motor in a $4000 car. I was being the rational man.

Why not a Gen 3 ?
Would be MUCH cheaper than a well prepped 4.6 in a manual, as adaptors are readily available, and if you want torque, that will give torque.

They weigh the same , the drivetrain will take it, and the ECus are readily available , tunable . There are specialists around who will wire it up reasonably.
Regards Philip A

[Freestyler]

I have the 4.4 Leyland terrier motor in my county, worked heads, efi worked mainfold, chipped computer and nozzel were fitted for LPG injection but not fitted yet. Huge amount of grunt in the bush and will maintain 100ks up a hill in 5th while towing trailer! My father was so impressed he has decided to hold onto his 1990 V8 county and fit a 4.6 to it. The engine is all rebuilt and ready to go in. Engine mounts, bellhousing, clutch, fly wheel will all bolt up. The 4.6 was a distributer less engine, but the county timing cover will fit which means you want have to alter your fan cowling. faily straight forward conversion, but the 4.6's did have problems with liners shifting. Good idea to have T sleeve fitted. But they are cross bolted, much stronger engine. Dad bought his engine for $3000 and has spent $10000 on it but is a long way short of $60000 for a new one