Engine suggestions

The Saint · Post by **The Saint** » Wed Sep 04, 2013 12:54 pm

I have recently purchased a Range rover based buggy. Pics of it can be seen in an earlier thread. The buggy has a Range rover classic chassis with 3.9 RV8, 5 speed manual (not sure which one) and I'm sure a Borg warner transfer box as I don't have the diff lock option on the transfer box selector.

The buggy has 33x12.50 tyres and I find it a bit sluggish compared to a '90 Range rover 3.9 V8 auto with LPG that I had years ago.
I want to fit bigger tyres to the buggy, so I will need more power.
Having a good read on here it seems that trying to tune the RV8 is an expensive game.
I want to keep a V8 in it, as I love the roar and torque. I would like more power and like to keep it as light as reasonably possible.

Do I tune my engine or start looking at installing another engine?

kiwicar · Post by **kiwicar** » Wed Sep 04, 2013 2:20 pm

Hi
a high geared 4x4 on a manual (as a result of the tires) is always going to feel sluggish compared to an auto on stock gearing. how you proceed really all depends on what you are after out of the car in the end.
If you want cheap-ish horsepower without too much work and don't care too much about around town fuel consumption then I would pull the engine, find a 4.2 crank, rods and pistons, get a new stock 3.9 cam of real steel, stage one heads a quick hone and a megasquirt set up and a set of long tube headers that should get you to 195 to 205 real bhp with decent torque, but it will still not be as quick off the line as standard gearing.
Next option is as above but add a supercharger off a 4.0 jag engine and a real steel blower cam, probably looking at 8lb boost and a real 275 bhp maybe a bit more and that should feel pretty brisk. However that is quite a bit of work if you do it all yourself, and that realistically is about a £3k budget and unless your gearbox is the newer 380 manual it won't last very long!
I know i keep saying this but a chevy LS 5.3 engine gives a genuine 260 to 300 bhp as is, you would need the Megasquirt at about £600 all in, an adapter for the box is about £60 if you make it yourself, about £120 if you buy one and the LS engine is about £1600 plus about £250 in bits to get it in and sorted if you do it yourself.
The trouble here again is the gearbox, the MPG will be much better than the rover with blower, probably about 10% better than with what you have now, but it will never be a nissan micra on fuel economy. With the chevy you could use a chevy auto and that will add about £300 to the budget, as you will need an adapter to the transfer box, but you can also sell on the manual box and clutch.
Your other choices are the V8 Diesel out the newer Range rover, that would give you good economy and be brisk!

The Jag XK8 engine, even without a blower it is a genuine 300 bhp and the auto box it comes with is very nice

.
Best regards
Mike

The Saint · Post by **The Saint** » Wed Sep 04, 2013 4:59 pm

Thanks for the reply.
It's going to predominately be a fun road car. I will be doing some fast off roading with catching some air, hence why I would like to keep as light as possible.
Due to it being a fun car I am not too worried about fuel consumption just as long as the fuel going in is directionally proportional to the fun coming out.
I haven't taken an accurate record, so this is rough but the 3.9 is doing 100 miles on £50 of unleaded making 12.54 MPG without too much right foot. I will keep a more accurate record to see what it is actually doing.
Oh the 3.9 has tubular exhaust manifolds with a Stainless exhaust.

A supercharger on a V8 has got to make the ultimate engine sound !!!!

ChrisJC · Post by **ChrisJC** » Wed Sep 04, 2013 5:09 pm

I would get a relinered 4.6 block, and built up an engine based on that. Perhaps a slightly torquey cam (e.g. RPi's TorqueMax). You could be able to get 250BHP quite easily.

Maybe also worth changing the diffs to about 4:1 instead of 3.54:1 to compensate for the larger wheels. KAM diffs to various ratios.

Chris.

landrovernuts · Post by **landrovernuts** » Wed Sep 04, 2013 8:03 pm

why not keep what you have got and fit a LT230 transfer box with 1.4:1 ratio instead of the Borg warner which has a 1.2 (ish):1 ratio. Much simpler and you get your centre diff back. Borg Warners are prone to seizing viscous couplings and stretched chains. You could even go 1.6:1 and worth checking the ratio calculator on the Ashcroft Transmissions website and choose exactly what suits you. You can always think about tweaking the engine when your happy with the gearing.

I have a 4.2 90 running 1.2:1 transfer box and 265/75 R16 tyres and it goes like a bat out of hell.

Toby

The Saint · Post by **The Saint** » Thu Sep 05, 2013 8:32 am

This has become a transmission suggestion thread

I do plan on some transmission changes but want to work back from the engine as the engine will determine the gearbox which might mean a change of transfer box.

I do like the Borg warner box as it reduces the turning circle (my Renault traffic LWB has a smaller turning circle than the buggy). I like that it only drives the rear wheels until they slip. It also works better for the fast low traction driving that I am planning. Most of all mine seems to be in good condition.

Is the Rover V8 one of the readily available lighter V8's

If I bought a 4.6 Rover V8 (they seem to be quite cheap on eBlag) What else would I need to change? I assume it wouldn't run on the 3.9 efi ?
What are the downsides of this engine?

kiwicar · Post by **kiwicar** » Thu Sep 05, 2013 9:46 am

Hi
on the 4.6 the 3.9 manifold could be used, the ECU would not and you would need bigger injectors. To do a 4.6 into your current car would cost a lot more than the 4.2 or the LS chevy or a 3.9 and a Jag blower as your first job on the 4.6 would be to re-sleeve it with top hat liners, £900 +Vat.
Best regards
Mike

The Saint · Post by **The Saint** » Thu Sep 05, 2013 10:20 am

I can see this thread becoming a long process of elimination.

From reading a lot of posts I did get the opinion that the 4.6 is the least reliable of the RV8's.

I have just had a look under the buggy and it has a LT77.

A few engines or cars (for engines) I have found on Eblag, not sure how good the prices are but it's a rough idea. Opinions please.

4.6 RV8 - Been touched on above
http://www.ebay.co.uk/itm/151110248680? ... 1423.l2649

Chevy L33
http://www.ebay.co.uk/itm/290960355537? ... 1423.l2649

4.2 V8 Jag supercharged - That has got to be a monster engine. I assume the seller knows it is going to cost a lot to fix or he would of done it himself.
http://www.ebay.co.uk/itm/130982924759? ... 1423.l2649

5.7 Monaro V8 LS1 - Seems like a lot of money.
http://www.ebay.co.uk/itm/151106520222? ... 1423.l2649

3.5 TVR Supercharged - If it would cost me £3k to build my own supercharged V8. It would be worth taking the engine out of this and breaking the car.
http://www.ebay.co.uk/itm/TVR-SUPERCHAR ... true&rt=nc

Chevy 4.8 V8 LS1
http://www.ebay.co.uk/itm/Chevy-V8-LS1- ... 232bf6cdde

4.0 Lexus V8
http://www.ebay.co.uk/itm/1995-LEXUS-LS ... 43bf2fc7e2

Not sure where else to search for V8 engines.

kiwicar · Post by **kiwicar** » Thu Sep 05, 2013 12:52 pm

Hi
the LR4 4.8, if complete "ready to run" as claimed, and by that I would expect ECU and loom, would be the best value of the straight engines, without attached car, the claims are a little optimistic in that you have to do some tuning work to get over 260bhp but it is very surprising the output from these smaller engines and there are Bonneville engines using the stock 4.8 crank and rods and getting over 1800 bhp.
The 5.3 is a pretty good deal as well but you would need another £600 for a a megasquirt type ECU and check how complete the ancillaries list is having said that I think at least one person on here has had one of these off this chap. The Monaro lump is about £1000 over priced, you can ge a new one for very little more than that.
The lexus option is a good one at the price if you can get it to fit it is quite a wide lump, having said that a few have been put in P% and P^ rovers so there is a pretty good chance it will fit. At only 119 miles that is not even halfway through it's life and it comes With a box and ecu.
personally I would avoid anything in a TVR wedge like the plague, the owners of these TVRs are true believers even by the standards of TVR owners and will be personally insulted if you don't immediately offer twice the asking price without even seeing the thing

and if they find out you are planning to remove the engine out of their precious and put it in a truck they will probably eat you

.
The 4.6 rover lump sets off too many alarm bells . . . if it was reconditioned 20k miles ago why is he selling it now? and for £350

if it was done using top hat liners then it is worth £800 as a parts engine if it was reconditioned without top hat liners then it does not make sense to wast the money on the gaskets, and what else wasn't done in the reconditioning I would avoid.
Yes as you can tell I think the Chevy L* series engine are about the best out there at the moment and I am not a big rover fan, however I do think the small main journal rover lump can be made into a pretty good work horse engine for sensible money with careful choice of parts, a willingness to do the work yourself and if you understand that you may well not be able to get the power out of the engine you want and be prepared to see there are cheaper alternatives. there are alot of people on here who have put more than £6k into rover lumps that barely make over 240 real bhp a £2400 gen 1 chevy crate motor will make that with a years guarantee and £5k of ford mod crate motor would see you to 350 bhp any day. In nearly every case where someone has build a "high out put" rover engine they have started convinced 250bhp is possible out of the rover with just another £500 spent on it but to be honest a 250bhp rover engine will cost you over £6.5k. 205, 210 bhp form a rover is cheep and easy, you can do it on SUs and a stock manifold but double your budget for every 10 bhp after that.
Best regards
Mike

volospian · Post by **volospian** » Thu Sep 05, 2013 1:23 pm

Only a couple of things worth adding:

The L33 is alloy, the LR4 is cast iron with alloy heads and the L33 is rated at 310hp as standard due to a higher compression ratio and a better cam. Those figures are for the truck intake. We'll maybe see what the car intake does soon

The monaro lump includes flywheel, clutch, wiring loom, ecu, plus ancillaries. The L33 price is a bare engine, so no coils, water pump, headers, ancillaries, loom, ecu, etc. If you go for new parts, as I have, you could easily add another £1500+ to the L33 price to end up with the other bits you'll need. Just a thought...

Regarding the Jag engine... do you need the 400bhp of the blown 4.2? The Rover lump won't be shoving out much real HP and the 3.2 Jag unit is overlooked (maybe for good reason, I don't know) but is rated at 240hp out of the box. You can get one for next to nothing, such as this. Even the 4.0 unit is rated at 290hp, and there are a few of them around, although these may be affected by nikasil and water pump issues which may put some people off, and the 4.2N/A unit is around 300hp.

The Saint · Post by **The Saint** » Thu Sep 05, 2013 1:35 pm

Thanks for the input. I thought I was up on car speak but obviously not. What do you mean by real bhp? Are we talking about a usable range rather than a peak?

What would the L33 and gearbox weigh compared to the 3.9 V8 and LT77?

volospian · Post by **volospian** » Thu Sep 05, 2013 1:44 pm

The Saint wrote:What do you mean by real bhp?

lol, I just meant "not pub BHP"

i.e. getting a standard 3.5 Rover, sticking a big carb on it and telling everyone "it must be putting out 240bhp, easy!" as I'm sure we've all had the pleasure of hearing in the past

I suppose it depends on the'box and engine trim. I don't know the weight of the L33 as such, but a mate and I lifted it up onto the engine stand easy enough the other week. It's really not that heavy, probably not that much more than a Rover.

/EDIT, It's not dissimilar to the RV8 in basic building blocks. Single cam, pushrods, rockers, all alloy construction, etc., so considering it is bigger than a RV8, I'd say, were it the same size as a rover, it would weigh similar... if you see what I mean, although this is based upon my experience of lifting both the RV8 and the L33 blocks up by hand.

As it is, it probably weighs more largely because it's simply bigger, unlike the LR4, which is both dimensionaly larger than an RV8 and has an iron block and thus obviously notably heavier because of it,

/ANOTHER EDIT. This Wiki says the "dry weight" of the 3.5 is 375lbs, while this site says the LS1 weighs in at 410lbs with accessories, but no manifolds... make of that what you will

kiwicar · Post by **kiwicar** » Thu Sep 05, 2013 2:39 pm

Hi
Sorry by "real bhp" I also mean non brochure/ tvr/ pub bhp, if you take a mas produced engine like the 1.8 mondao engine and dyno test 10 off the production line you will get rear wheel results that are about 120 to 130 repeatably and pretty reliably, if you then take the same dyno on the same day and stick a just run in rover 3.5 or 3.9 rover on it that has a mild cam upgrade, tubular headers stage one heads and sort the ignition and mixture you will see about 190 to 205 bhp over a run of say 6 to 8 pulls, chuck out the highest and lowest and average the rest and thet is a proper result in real bhp. There are many ways of fooling a dyno, tap the brake peddle as you do the run down after the run, disconnect the altinator/power steering belt stand on the hold down strap as the run down starts over inflate the tyres, do the run on a cold wet day with no correction. TVR have spent years making silly claims about outputs from what are basically near stock rover crate engines these numbers are then used by the TVR aftermarket as referances to "correct" the readings of certain dynos used by the TVR aftermarket industry, next thing you know you have BHP run away.
Other parts of the industry are as bad, it is very rare to see crate engine outputs repeated in tests on dynos that have several pulls of different engines and engine specs across the same conditions, this is where the small L* series engines seem so good, far more so than the 5.7 and 6.0 sized engines the 5.3 and 4.8 repeatadly deliver what is claimed.
The bigger displacement engines seem to vairy fare more from what is claimed, many do reproduce what is claimed in US magazine tests and even a bit more, others fall 5% or 10% short.
To me real horsepower is repeatable on the day, referanced to another real engine and on an engine running as it is intended to run with everything attached.
Best regards
Mike

kiwicar · Post by **kiwicar** » Thu Sep 05, 2013 2:48 pm

"/ANOTHER EDIT. This Wiki says the "dry weight" of the 3.5 is 375lbs, while this site says the LS1 weighs in at 410lbs with accessories, but no manifolds... make of that what you will"
The number you quoted here is from the p6 3.5 engine prior to the thicker walled more heavily webbed range rover update of the block casting. A fully dressed out 4.6 rover engine has got to be 50 to 75lb heavier than that, just the extra metal in the big journal 4.6 crank has got to be 8 or 9 lb

.
best regards
Mike

The Saint · Post by **The Saint** » Thu Sep 05, 2013 2:51 pm

Cheers Mike, I've got to sit down and let my brain absorb that.

Edit - The 'real bhp' bit.