Hello all, I have a really nice 00 D2 with the 4.0 that has developed pitting in the cylinders, So I bought a 4.6 with good engine with the intention of swapping the engines. Before I swap, while the 4.6 is on the stand, I decided to rebuild it from the crank out. Its my hope to build the 4.6 out using 4.0 pistons for the slightly higher CR.
OK here is what I discovered. I think someone rebuilt this before me.
1. I have a 4.6 (block is sleaved)
2. the crank though is stamped "Rover 4.0"?
How do I identify which con rods, and pistons I have. The 4.0 and the 4.6 have different rotating assemblies.
Google hasn't been any help, nor has British Atlantic
Im stuck...Thank for any advice guys

 

Your 4.6 might be a 4.0, the crankshafts are different and marked as such. All rover V8's are sleeved, I would check the engine number, my gut is that 4.6 is a 4.0

 

Thank you for the response, I thought the 4.0s were bored, and the 4.6s were sleeved. is there an engine number list I can reference, once I find the cast number?

 

The engine number is beside the dipstick, you have to search the for an engine list are a bunch of them

 

I have owned an 03 D2 (4.6L) and a 99 D2 (4.0L) Both were sleeved...4.6L suffered slipped liner and toasted the engine, bought another 4.0L, pinned the liners, and rebuilt it with a 4.6L cam (rest was 4.0L parts). runs fine, got 20K+ on her.

 

you both are correct, thank you. i ran the engine number and it is a 4.0. some one replaced the 4.6 in an 03 with 4.0.
so... now I'm left with some different options. I had my heart set on a 4.6 with 4.0 Pistons. but I'm not going to spend another 1000 on another "4.6".
So i reached out to DJ at crower and priced a stage 2 cam and new lifters for the 4.0. I may consider shaving a little off the heads to slightly raise the CR to 10.xx. plus a little port matching and mild deburring. any wise experienced advice on this direction? (fyi I'm typically builder of turbo'd drag bikes and pulling 454's; these Disco's seem to be fickle and in the middle)

 

There really is no room to shave the heads,I had to toss a set of heads that could not be trued they do not have a lot meat. You need to face a reality these were built as 4 wheel drive luxury utility trucks, you are never going to get a lot more power out it. You could look into the performance builds, but they are mostly race engines.

I had the same issue bought an engine out a 03 and it had been swapped with a 4.0, it sucke dbut I manged to sell most of the bits and recoup my costs

 

I would only resurface the heads, not mill the heads down, if you cut them down too far you can have interference/fitment issues with the lower intake manifold. port matching...go for it. I ported mine by bolting a set of intake and exhaust gaskets down to the heads and used a sharpie to color in anything hanging out past the gasket into the air flow. then took the gaskets off and ported them out until the sharpie areas were gone. After that I just tried to polish/smooth them out. Between that and the 4.6 cam in it, it is definitely peppier than a regular 4.0 is, but lets face it, it's never going to be a Ford Raptor.

Few pics of my rebuild.

 

I rebuilt my 4.6 and it has plenty of power. The heads were shaved .015" and that is the absolute max that will work without major modifications. I put a small cam in and did head cleanup. I opened the ports a little but not all the way to the gasket. Biggest work I did was smoothing out the intake runner in the heads. There is a sharp edge down in the runner I rounded off and polished up. Stock gears on 32's and no problem pulling my 19' center consol even when loaded with people and luggage. Never needs to downshift on the highway. These engines were designed for tq and they have plenty of that.

 

hey Texas, that block/ head look great, did you have it steamed?

I think 15 off the heads is all that i can take. thanks for the advice guys. Port matching is important to keep intake track velocity up and clean. every little bit helps.