Engine Rebuild - Performance/Reliability Upgrades? - Land Rover Forums

Mountain Goat · #1 12-16-2011, 03:15 PM

My Rover went 120,000 miles on the original engine and could go longer I'm sure. But I have a bottom-end knock that is gradually getting worse even with 15-W40 oil. I've confirmed by listening to it on a scope and getting a second opinion from a shop that it is a bearing in the bottom end, so I'm planning to rebuild it.

Actually, I'd do it myself but I just got an e-mail from the college that their automotive department is seeking engine rebuild projects. $1000 deposit, then the price is cost of parts + $7/hour. It would be worked on by a senior-level automotive student and supervised by the professor. They say a typical rebuild comes in at $1500, so I'm guessing a bit higher for a Rover V8. Still, the rest of the rig is in good shape, I've thoroughly inspected it and done plenty of work on it myself, so the price seems highly reasonable. I signed up my rig for the rebuild and will need to have a serious conversation with the instructor to determine his competence & the success rate of his students, but with it being an upper division class at a respected 4-year university I'm not to concerned.

My question is this: what performance or reliability upgrades should I do? I'd love it if the finished engine had a little more grunt than it does now, but I don't want to sacrifice reliability. I heard somewhere about using the crank from a 4.6, is there any benefit to that?

Thoughts?

Savannah Buzz · #2 12-16-2011, 04:10 PM

Not sure about more power (or if the other older, somewhat worn parts, could take it, or just fail sooner). Reliability sounds good, like oil pump, timing chain, etc. Be sure that prof has a copy of the RAVE, even if you have to drop it off on a USB drive.

That said, we just had posts about replacing bearings without removing engine, from pedronz, check out engine bearings. He is a very resourceful individual, in Wellington, New Zealand.

Mountain Goat · #3 12-16-2011, 04:23 PM

Yeah I was thinking I'll give a copy of the RAVE to the professor, that manual has saved my butt so many times working on this rig. If I could do just the bearings that would be great, but the truck is scheduled for a head gasket failure any day now. It's overheated once at the dunes (in April, not August) and has always steamed/smoked a bit when I first start it up. On top of that I have to add a quart of coolant every 1000 miles or so, so really a full rebuild can't hurt, especially at $7/hour...

Spike555 · #4 12-16-2011, 07:29 PM

Go for the full rebuild, the 4.6 crank wont do you any good without a ECU remap.
Just let them do their thing, and then make damn sure you drive her nice and easy for the first 500 miles and then change the oil and filter at 500 miles.
They will replace the timing set, lifters, etc.

jafir · #5 12-16-2011, 10:31 PM

You could put a 4.6 cam. If you did the 4.6 crank too, you'd need pistons too. Then you'd have a full 4.6, just like in the GEMS range rovers. According to people smarter than me, most of the GEMS computers have both 4.0 and 4.6 maps in them, so if you did the full 4.6 upgrade, you could just have someone with testbook flip it to the other map.

thehun · #6 12-17-2011, 12:11 AM

if you are going to spend 1500 bucks on a rebuilt..might as well convert the sucker to a SBC

Mountain Goat · #7 12-17-2011, 12:15 AM

I may just stick with the 4.0 stuff, but honestly I've always wanted a 4.6. It might have just enough power to stave off differential gears for a few more years. So is it just the cam, crank, pistons, and ECU programming that are different? And would the cam alone give any benefit?

I guess my main concern is the ECU remap. There's a very small Rover market in my area, I don't think anyone will have testbook. Is that something they'd be willing to do at a dealership, and would the cost be exorbitant? There is a dealer about 3 hours from my house. Would it drive acceptably with the 4.6 parts until I have a chance to have it reprogrammed? I mean I'd most likely at least have to make a trip down to the dealer.

Mountain Goat · #8 12-17-2011, 12:20 AM

Quote:

Originally Posted by thehun

if you are going to spend 1500 bucks on a rebuilt..might as well convert the sucker to a SBC

I may be wrong, but it seems like a fuel-injected SBC would be well more than that when all is said and done. I'm not really a fan of carburetors on off-road rigs.

Mountain Goat · #9 12-17-2011, 12:44 AM

Would the crankshaft, connecting rods, and cam all have to come off a GEMS 4.6? Or are they the same on the Bosch engine?

Savannah Buzz · #10 12-17-2011, 05:29 AM

IMHO - getting a group of students and a faculty member to do something without the book (i.e., conversion to alternate size engine) would decrease the odds for success or certainly stretch out the project time line. A college student is a high school kid with 6 month's experience. Now I am somewhat biased, since I mostly have mechanical, electrical, computer, and civil engineering groups at my campus.

That said, there are some high school students on this forum that could tackle such a project. And we have forum members who have rebuilt their engine as their first big DIY project.