V8 questions

O

Olly R

Guest

• May 2, 2005

• #1

Hello all, and happy bank holiday monday.

Until a year or so ago, I drove a Stage One V8 109 (on LPG) that I loved to
bits, but had to sell it. I'm soon going to be in the market for a
replacement Land Rover (hooray!) and whilst my head tells me that I should
really be looking for a sensible Tdi-engined vehicle, I'm not sure that I'll
be able to resist the lure of the V8.

Having had some not terribly good experiences with a carbed 3.5 on LPG
(maybe I was unlucky), I was wondering about the injected V8s. So the
questions are

Is the 3.9 V8i a much better engine?
Does is get usefully better mpg?
Are there issues with running the injected engine mostly on LPG?
If I bought a landy with a different engine, with a view to replacing that
engine with a V8, are there any particularly suitable/unsuitable donor
vehicles? I'm really after a LWB station wagon.
Presumably the 3.9 needs a catalytic converter, and therefore a closed-loop
gas system, all of which is more expensive to install?
So maybe if all this will cost loads, is it on balance best to stick with
carbs, and hope I get a good 'un?

Any thoughts would be gratefully received.

Cheers

olly R

 

R

Richard Brookman

Guest

• May 2, 2005

• #2

Olly R wrote:
>
> Is the 3.9 V8i a much better engine?

So they say - injection better than carbs for general ease of use and
reliability, more power compared to standard carb setup, should stay in tune
better. Downside is that if it goes wrong you have an ECU to replace or
bodge.

> Does is get usefully better mpg?

Figures for the RRC suggest 16mpg for 3.5 carbs against 17mpg for 3.9 V8i,
so not a great deal in it, but perhaps it could be regarded as "useful".

> Presumably the 3.9 needs a catalytic converter, and therefore a
> closed-loop gas system, all of which is more expensive to install?

No knowledge of LPG, but if you're running it on unleaded the cats issue
depends on the date of manufacture. Key date is around 1992/1993 in the UK.
Before this, the emissions limits were higher and a good engine would get
away without the cats. After this date, the limits were drastically reduced
and you are unlikely to be able to do without. Some workarounds, to do with
the purpose of vehicle and GVW - you might be able to persuade a tester that
the newer limits don't apply to your vehicle. This has been discussed
several times,with no definitive answer emerging. Suggest you Google it.

> So maybe if all this will cost loads, is it on balance best to stick
> with carbs, and hope I get a good 'un?

On balance, 3.9 every time. Lovely engine.

HTH

--
Rich
==============================
RR 4.6HSE (up for sale)
S2a SWB (not for sale)
Tiggrr (V8 trialler)

 

O

Olly R

Guest

• May 2, 2005

• #3

"Richard Brookman" <[email protected]> wrote in message
news:[email protected]...

> injection better than carbs for general ease of use and
> reliability, more power compared to standard carb setup, should stay in
tune
> better. Downside is that if it goes wrong you have an ECU to replace or
> bodge.

Yes, and also more electrics to worry about if installing a V8i into a
previously-not-V8i-landy.

> > Presumably the 3.9 needs a catalytic converter,

> This has been discussed
> several times,with no definitive answer emerging. Suggest you Google it.

Will do.

> On balance, 3.9 every time. Lovely engine.
>
> HTH

It does indeed - thanks Richard.

olly R

 

O

Olly R

Guest

• May 2, 2005

• #4

"MVP" <mr.nice@*nospam*softhome.net> wrote in message
news:[email protected]...

> After much thought, advice and poking around the great
> interwebnet-thingy I've settled on (and hope to soon buy) a 3.9
> injection LPG'd Land Rover.
> I've always been a big fan of diesels (with the exception of the wifes
> saab I've not had a petrol vehicle in years) and the faf of carbs make
> sme nervous. but a 3.9 V8 is my choice, I'm wary of the electronics
> but willing to have a go with this one.

Yes, I'd been reading your threads before.
I don't want a disco though, so am interested to hear people's thoughts
about putting a V8i into a 110 or Defender 110.

> Research and advice suggests that the 3.9 is indeed, a good-un.

Yes, a colleague of mine has just bought an H-reg RR with this engine on
LPG, and it is fabulous.

Thanks Mark.

olly R

 

H

hugh

Guest

• May 2, 2005

• #5

In message <[email protected]>, MVP
<mr.nice@*nospam*softhome.net> writes
>On Mon, 2 May 2005 10:38:51 +0000 (UTC), "Richard Brookman"
><[email protected]> wrote:
>
>>Olly R wrote:
>>>
>>> Is the 3.9 V8i a much better engine?
>>
>>So they say - injection better than carbs for general ease of use and
>>reliability, more power compared to standard carb setup, should stay in tune
>>better. Downside is that if it goes wrong you have an ECU to replace or
>>bodge.
>>
>>> Does is get usefully better mpg?
>>
>>Figures for the RRC suggest 16mpg for 3.5 carbs against 17mpg for 3.9 V8i,
>>so not a great deal in it, but perhaps it could be regarded as "useful".
>>
>>> Presumably the 3.9 needs a catalytic converter, and therefore a
>>> closed-loop gas system, all of which is more expensive to install?
>>
>>No knowledge of LPG, but if you're running it on unleaded the cats issue
>>depends on the date of manufacture. Key date is around 1992/1993 in the UK.
>>Before this, the emissions limits were higher and a good engine would get
>>away without the cats. After this date, the limits were drastically reduced
>>and you are unlikely to be able to do without. Some workarounds, to do with
>>the purpose of vehicle and GVW - you might be able to persuade a tester that
>>the newer limits don't apply to your vehicle. This has been discussed
>>several times,with no definitive answer emerging. Suggest you Google it.
>>
>>> So maybe if all this will cost loads, is it on balance best to stick
>>> with carbs, and hope I get a good 'un?
>>
>>On balance, 3.9 every time. Lovely engine.
>>
>>HTH
>
>After much thought, advice and poking around the great
>interwebnet-thingy I've settled on (and hope to soon buy) a 3.9
>injection LPG'd Land Rover.
>I've always been a big fan of diesels (with the exception of the wifes
>saab I've not had a petrol vehicle in years) and the faf of carbs make
>sme nervous. but a 3.9 V8 is my choice, I'm wary of the electronics
>but willing to have a go with this one.
>
>Research and advice suggests that the 3.9 is indeed, a good-un.
>
>
>Regards.
>Mark.
If you are buying one already converted check out the LPG side
thoroughly. It can be more hassle and almost as expensive to sort out a
dodgy installation than to convert from new. Also look for a conversion
certificate and check with your insurance company as to whether they
will require an LPGA one - some do.
--
hugh
Reply to address is valid at the time of posting

 

O

Olly R

Guest

• May 2, 2005

• #6

"Badger" <[email protected]> wrote in message
news:[email protected]...
>
> Go for it, you know you want that burble!!!

Thanks for your thoughts!
Now just supposing I found a suitable vehicle, roughly how much do you
suppose someone might charge to put a 3.9 in, all things being equal?
(I live in Scotland. Can you see where this might just possibly be
leading....?)

olly R

 

O

Olly R

Guest

• May 2, 2005

• #7

"hugh" <hugh@[127.0.0.1]> wrote in message
news:[email protected]...

> If you are buying one already converted check out the LPG side
> thoroughly. It can be more hassle and almost as expensive to sort out a
> dodgy installation than to convert from new. Also look for a conversion
> certificate and check with your insurance company as to whether they
> will require an LPGA one - some do.

Thanks Hugh, my 109 ran on LPG, with quite a dodgy conversion,
unidentifiable components, tank put in the wrong way up, wrong hoses and
things, and I did have to pay quite a bit to get it sorted for when I needed
a LPGA certificate. And after all that, it still never really ran properly!

olly R

 

P

PDannyD

Guest

• May 2, 2005

• #8

On Monday 02 May 2005 11:38, Richard Brookman([email protected]) wrote in
message <[email protected]>

> Olly R wrote:
>>
>> Is the 3.9 V8i a much better engine?
>
> So they say - injection better than carbs for general ease of use and
> reliability, more power compared to standard carb setup, should stay in
> tune
> better. Downside is that if it goes wrong you have an ECU to replace or
> bodge.
>
>> Does is get usefully better mpg?
>
> Figures for the RRC suggest 16mpg for 3.5 carbs against 17mpg for 3.9 V8i,
> so not a great deal in it, but perhaps it could be regarded as "useful".

Yikes! My old 3.5 bobtail averaged 25+mpg on hilly twisty roads. There must
be some heavy-footed drivers out there!

 

O

Olly R

Guest

• May 2, 2005

• #9

"PDannyD" <[email protected]> wrote in
message news:[email protected]...

> Yikes! My old 3.5 bobtail averaged 25+mpg on hilly twisty roads. There
must
> be some heavy-footed drivers out there!

I used to get about 11 mpg from the 109 - but as I said, the engine was
sh*gged.
Was your bobtail very light?

olly R

 

B

Badger

Guest

• May 2, 2005

• #10

"Olly R" <[email protected]> wrote in message
news:[email protected]...
>
> "Badger" <[email protected]> wrote in message
> news:[email protected]...
>>
>> Go for it, you know you want that burble!!!
>
> Thanks for your thoughts!
> Now just supposing I found a suitable vehicle, roughly how much do you
> suppose someone might charge to put a 3.9 in, all things being equal?
> (I live in Scotland. Can you see where this might just possibly be
> leading....?)

Pulling one V8 and fitting another is the relatively easy bit. To get the
benefit from the 3.9 you really want to ditch the std 3.5 exhaust and fit a
performance stainless one, the 3.5's single-outlet manifolds will choke a
3.9. The gas install, as others have said, can be a right royal pain if you
have to resort to sorting other people's mistakes. Converting to EFI
involves dropping the fuel tank to change the pump for an EFI rangie one,
amongst other things, in itself a few hours of work - if a towbar is in the
way, that can add time getting the no-doubt rusted bolts out!. The wiring
isn't as bad as some make it out to be, there's only 4 wires to connect, and
find a suitable location for the ECU.
As to where this could lead, feel free to email me off-group via my website
if you want to discuss anything in any further detail.

--
Badger.
B.H.Engineering,
Rover V8 engine specialists.
www.bhengineering.co.uk
www.roverv8engines.com

 

P

PDannyD

Guest

• May 2, 2005

• #11

On Monday 02 May 2005 13:01, Olly R([email protected]) wrote in
message <[email protected]>

>
> "PDannyD" <[email protected]> wrote in
> message news:[email protected]...
>
>> Yikes! My old 3.5 bobtail averaged 25+mpg on hilly twisty roads. There
> must
>> be some heavy-footed drivers out there!
>
> I used to get about 11 mpg from the 109 - but as I said, the engine was
> sh*gged.
> Was your bobtail very light?

Not amazingly light but I do tend to get a higher than average mpg on all of
my vehicles.

 

O

Olly R

Guest

• May 2, 2005

• #12

"Badger" <[email protected]> wrote in message
news:[email protected]...
>
>> >
> > Thanks for your thoughts!
>
> As to where this could lead, feel free to email me off-group via my
website
> if you want to discuss anything in any further detail.

Splendid. I'll carry on mulling it all over, and when I get a proper plan,
I'll get in touch.
Thanks again.

olly R

 

A

Austin Shackles

Guest

• May 3, 2005

• #13

On or around Mon, 02 May 2005 20:57:13 +0100, PDannyD
<[email protected]> enlightened us thusly:

>Not amazingly light but I do tend to get a higher than average mpg on all of
>my vehicles.

probably coasts down hills

seriously though...


3.5 hotwire disco got about 18 mpg on average motoring without trying to be
economical. still does, probably, and typically gets about 13 mpg on LPG,
although I got 193 miles from 2 litres less than a full tank on a long run
at the weekend, which is a tad over 14.

the word on 3.5 vs 3.9 is that the 3.9 is better on economy provided you
don't habitually use all the extra power... injection vs carbs is probably
more efficient ('specially a late hotwire with lambda sensors) due to more
reliable fuel metering.

In my case, 110 auto with the saem type of gas system got about 11 mpg, but
the engine wasn't as good as the current one.

--
Austin Shackles. www.ddol-las.fsnet.co.uk my opinions are just that
"'Tis a mad world, my masters" John Taylor (1580-1633) Western Voyage, 1

 

H

hugh

Guest

• May 3, 2005

• #14

In message <[email protected]>, Olly R
<[email protected]> writes
>
>"hugh" <hugh@[127.0.0.1]> wrote in message
>news:[email protected]...
>
>> If you are buying one already converted check out the LPG side
>> thoroughly. It can be more hassle and almost as expensive to sort out a
>> dodgy installation than to convert from new. Also look for a conversion
>> certificate and check with your insurance company as to whether they
>> will require an LPGA one - some do.
>
>Thanks Hugh, my 109 ran on LPG, with quite a dodgy conversion,
>unidentifiable components, tank put in the wrong way up, wrong hoses and
>things, and I did have to pay quite a bit to get it sorted for when I needed
>a LPGA certificate. And after all that, it still never really ran properly!
>
>olly R
>
>
Been quicker to say what was right
--
hugh
Reply to address is valid at the time of posting