I have been in contact with the owner of ACR, a Mr Roland Marlow and here is what he has to say about his engines.

"Hello Julian,

Thanks for your email regarding your Disco II.

The 4.0 and 4.6 across the Range Rover and Discovery have a
reputation for a number of problems, which are now well
documented. All engines have the potential to develop a crack
or develop porosity behind the cylinder liners, which leads to
the pressurization of the cooling system.
This defect is attributed to core shift problems in the
foundry, compounded by the heavy interference used to retain the
cylinder liners. The problem is often triggered when the
cooling system overheats, or runs low on coolant. Land Rover
failed to include coolant level monitors on this era of
vehicles which does not help.

Cylinder liner slippage is often a result of serious
overheating, as is cylinder head warpage. However, a noticeable
proportion of later ~ 2003 blocks which come back to us have an
odd loose liner due to machining errors, which result in a hot
tapping noise.

The ACR remanufactured stripped engines have a number of well
tried and tested modifications which sort out the cylinder
block and liner issues. We fit heavy duty flanged liners, which
allow mechanical rather than friction location of the liners,
along with proper sealing at both the top and bottom of liner.

We offer a standard 4.6 stripped engine which is what I
recommend if you want to keep the vehicle as Land Rover
intended. A 4.0 is definitely a backward step performance wise,
and would not be our recommendation.

If you want extra power, then the 4.8 Hi Torque package is our
recommendation. This is a very popular upgrade, and fits right
in with no other changes needed. It gives a noticeable
improvement in the overall performance, and we can squeeze even
more out with an ECU reprogram too!


Engine wise, I would recommend the ACR stripped engine full
package. This includes the main engine, with the valve covers,
oil pan, front cover, oil pump, front pulley and installation
gaskets etc. These parts are not included from other suppliers,
and would otherwise have to be renewed or reused from the old
engine.

Overall this makes the install easier and cheaper.

4.6 is £ 2940 + £ 400 core charge.


The costs for the Hi torque 4.8 upgrade are on the bottom of
this Rover V8 Engine - V8 Performance Engines - Land Rover Engines - Jaguar engine Off road racing page of our
website. These prices include core charge.

We have to ship these air frieght these days, and the US EPA
regulations add an additonal burden paperwork wise for our
shippers. I will forward some pricing once we have recieved
quotations from our shippers.

Regards,

Roland."

I did a currency conversion to get the figures in USD and heres what I came up with, excluding shipping costs.

Option 1 being the standard 4.6 he mentioned above:

£3340 = $5,522.85 core charge included, plus shipping

Option 2 being the performance boosted 4.8 Hi Torque WITH the CNC big valve upgrade:

£4232 = $6,994.59 plus shipping. Core charge included.

What are your thoughts everyone? Anything about his engines that stands out? Do the national suppliers (Atlantic British, Cannibal and GPR) use the same type of parts? So far I think this would be a pretty good deal, especially for the 4.8. Having a reman engined WITH the performance boost is probably every D2 owners wet dream and Id love to get my hands on it. I figure these guys are engine so they gotta know Rovers and Jag more than any yanks. Plus Bill of GBR spoke very highly of ACR and said they are they only supplier of his engines so.

 

The GPR motor has Top Hat (Flanged) liners, a cam with a bit more duration, ceramic lined coolant passages, and ARB head studs. I installed a 4.0 GPR complete motor. By complete, I mean everything from the lower intake plenum to the oil pan including a new oil pump and front cover, along with a new water pump.

I've been very happy with the performance of the engine, but even more impressed after I finally installed 4 new O2 sensors, which smoothed out the fuel map considerably and eliminated a bit of a rough idle and a slight stumble under acceleration.

Overall, I have been very pleased with my decision to go with GPR.

I can't speak to the quality of the others.

 

I would say our domestic engine suppliers are every bit as capable as ones from the UK. Seeing as how the original Rover engines routinely go 100k+ with all of their manufacturing defects, any proper rebuild will outlast most D2's.


If you have your heart set on more power, you can get an 86mm crank (stock 4.6 is 84mm) and a hotter cam and install them in a block machined by GPR for your 4.8 linter engine. That will save a bunch on shipping. Personally, I'm more than satisfied with the power from the 4.6. If you want to get back some of the performance lost to larger diameter tires you should spend the cash on the correct gears.

 

if you had asked 5-years ago about ARC i would have yes, even over Turner.
But now there places in the states that have focused on this niche market. there are at least 4 good options that i know.
the more work that stays here (the states) the more people may get into it; Like one of the large engine re-manufactures.
which again should help the purchaser with better pricing and warranties.

as far as size they have taken these things to over 5 liters and 400 hp. But they are like SBC over there, if you blow it go to the bone yard and grab another.

 

I think ACR is a good option but the shipping would be ridiculous and the support would be difficult. GPR and Cannibal offer great options as well as Atlantic British for the NA owners. I am sure Cannibal and GPR would build you a 4.8 if you really want it.

 

I'd just stay with a 4.6 and get a stage 2 cam w/ matching lifters. If the majority of the guts on the 4.8 are still Land Rover stock parts I'd consider that, being that you will need to replace things in due time.

 

For that money buy 4-5 '98-02 Discos and keep em on standby.

 

If wish to keep the truck your whole life. I would spend the extra cash and get the upgrade in performance. See what you can get done in the states though.

 

I don't think ACR has any advantage over the several time-tested local shops as mentioned above, except in the area of displacement. The 4.8L is certainly intriguing and tempting, however:

-Can they account for US spec differences (emmissions requirements, ECU, etc)?
-Would it shorten the life of the transmissions?
-How much is too much displacement out of an already stroked block?
-Are MPGs adversely affected? What's the warranty for US buyers?

These are things I'd want to know in detail, seeing examples over a long period of time before I pulled the trigger on a big purchase like that. That said, if everything panned out favorably, I'd get a 4.8L in a heartbeat!

 

I don't know, but RPI has a 5.2 RV8 option.