Which V8?

[Gazzar]

I'm planning a 109 SW build, long way in the future but as I've just picked up a V8 to gearbox adapter I'm now thinking about what engine to fit.

I've decided that I want a rover v8, no good reason other than I want it to be brisk, strong, clean and fairly reliable. I don't do mega miles so mpg isn't an issue.

But which one?

I don't think I need a 4.6, I'm not sure that the 3.5 will be enough, it's going to be a heavy car.

It's got to be injection: the smell of petrol on the street when a classic goes by is not as appealing as it was when I was younger.

What's the 3.9i like? What's the difference between that and the 4.0? Which has the improved oil pump? What runs on a standalone ECU without complex alarms and stuff?

Which has the problem with the poor tolerances and requires top hat liners?

In summary, what do I buy?

Oh, and it's going to have a R380 + LT230 so the torque shouldn't be a problem.....

Thanks?

G.

[tacr2man]

Why not just look for a decent stage 1 V8 , they came with the lT95 and integral transfer box , a stronger and more reliable set up than an R380 . You also get the CV joint front axle . I had one when they were current model , it went pretty well , even when towing , the only mod I made was removing the inlet restrictors . You will end up with an appreciating asset rather than a bitsa . JMHO

[elbekko]

Always get a bigger V8.

[Bowie69]

Biggest you can find.

Serp front ended V8s have the better oil pump, put simply, and if you get a 3.9 serp you can run it on hotwire quite happily, and that does kinda unplug from the rest of the car without issue.

I would still look for a 4.6 (or bigger....) and squirt it.

[Gazzar]

MS would be on the wish list but I'd be planning on getting it running and legal before I go MS.

What engines suffer most from the slipping liners?

and what versions have the Serp front end and run on hotwire/standalone ECU? And to they all connect up to the same bolt pattern and flywheel?

Disco 1 v8 3.9i

P38a?

Disco 2?

Cheers!

G.

[Gazzar]

Why not just look for a decent stage 1 V8 , they came with the lT95 and integral transfer box , a stronger and more reliable set up than an R380 . You also get the CV joint front axle . I had one when they were current model , it went pretty well , even when towing , the only mod I made was removing the inlet restrictors . You will end up with an appreciating asset rather than a bitsa . JMHO

The reason I'm going the bitsa route is that I've got all the bits! And by the time I strap on an Aircon pump, PAS pump and all the other stuff that a spouse requires in a car then I'm sapping a fair few horses from the 3.5.

Plus the S1V8 is carbs, not keen on carbs, to be honest, too dependant on experience, rather than expertise. I don't mess with them enough anymore to get them in tune easiy, whereas the injection setup is more like the diesel experience.

[smallfry]

All the engines will take a manual RR/Disco flywheel and clutch, but be warned, they might not fit inside your bellhousing. It depends on what you use............

All 4.0 and 4.6 have a serpentine front but a slightly different arrangement with the front cover and oil pickup. Oil filter points straight down. Also has a different sump. No distributor.

Only late RR classic and Disco 1 had the "standalone" Hotwire system. P38 and Disco 2 did not.

ALL the bigger bore engines can suffer liner problems, with the 4.6 seemingly the worst, then the 4.0, and then the 3.9/4.2.

However, I have never had a 4.6 or a 4.0 personally, but all three 3.9s I have had , failed miserably in this respect. I am building another block up ATM which has pressure tested OK, but I am not filled with confidence in it, even though it will only be a temporary fitment.

If I were you I would stick with a 3.5, and the money you will save on NOT having to have top hat liners fitted, you can spend on Megasquirt if you must.

[Bowie69]

One thing not mentioned, budget?

[smallfry]

A whole sentence disappeared off me post.................

Late 3.9 engines (late 93 on) have serpentine fronts with the new oil pump but still have a distributor. Oil filter points forward and downward as per earlier engines.

And another thing I have observed over the years, is that it would appear that running the larger bore engines

on single point LPG systems tends to aggravate the liner problems..................

Probably due to poor setup ?

As Mr Bowie rightly says, its all a question of budget and how much you are prepared to throw at it !

[Gazzar]

Budget? Tight fisted git!

I think I'll buy a D1 v8i, budget £800 for a car and £400 for an engine. Should allow me enough to do a semi-decent clean up and check over.

G.

[Hybrid_From_Hell]

For a budget V8

1st Choice 3.9 or 4.0 Serpentine

Revvy, more power than 3.5 no water / liner issues a la 4.6

2nd choice

3.9 V belt

Cheaper than options1 dizzy driven oil pump vs serp crank powered

if possible go for a cross bolted block but no eassential

con also squeally belts now and again

Nige

[Gazzar]

Sounds like a plan!

I'll keep an eye out over the next few months and see what's available locally on ebay.

[FridgeFreezer]

V8 P38's are dirt cheap, any P38 will have the serp front & cross-bolted block, later Thor (bunch-of-bananas) inlet manifolds gain you some torques at the low end. Failing that, 3.9 or 4.2, as late as you can manage.

[Hybrid_From_Hell]

^^

Agrred

BUT

You can't get a 4.6 4.0 GEMS or a THOR 4.0 4.6 running really without going Megasquirt.........................

On the other hand tho ..............

[FridgeFreezer]

Well, you could run a 4.0 with a 3.9 hotwire setup, but that seems a big bundle of wire to throw in.

[Hybrid_From_Hell]

Er ...4.0 = no dizzy doesn't it ?,,

[Bowie69]

Er ...4.0 = no dizzy doesn't it ?,,

Correct...

[elbekko]

Pretty sure you can get the GEMS running if you disable the immobiliser (apparently very easy, haven't done it myself). The Bosch is a bit more cumbersome...

But really, don't be afraid of the bigger bore engines. To me the slipped liner is still pretty much a unicorn...

[Gazzar]

I've no problem with bigger, no problem with immobilisers, but an just reluctant to put too much integrated stuff in a series!

I've just seen a 3.9 disco go on ebay for £410, so I'm planning in getting one of these and going with that, maybe start looking this time next year.

THanks!

G.

[FridgeFreezer]

When I had a 3.9 in my 109 it certainly went very nicely, more than adequate I'd say.

[Gazzar]

I like "more than adequate".

I've driven adequate and , well, it's inadequate.

G.

[Ally V8]

I'd use a 3.5,esp if you can find a donor D1 3.5efi. It gets you the whole deal,engine and a hotwire EFI system. The 3.5 motor is bags more reliable than any of the 94mm bore rubbish,and will stand amazing levels of abuse.A fresh one of those will be plenty for the application and just need sensible care.No expensive top hat liners,or fiddling with fuel maps etc.

[FridgeFreezer]

I've had two of those 94mm bore rubbish engines and neither has given a single problem.

[Ally V8]

Blimey,they made two good ones then... Fair enough you have been lucky,I have been in the horrible situation of telling plenty of P38 and D11 v8 owners that their engine is toast. If LR wanted to go to 94mm and make it reliable they needed better quality control or to have used stepped sleeves in the first place.

If the OP is going to go to all this effort then a reliable engine is the basis of this.Its far cheaper to start with a good 3.5 than to buy or build a stepped sleeve 94mm block.All the 109v8's and 101FC's I've driven have had plenty of go - esp considering their steering,brakes and suspension.

[FridgeFreezer]

Ally - I'm not denying the bigger bores are more likely to have problems, but the likelihood seems to be vastly exaggerated. These days, getting a block top-hatted is much cheaper than it used to be, and the advantages of the newer style lumps shouldn't be ignored.