Talk Morgan

Plus 8 capacity.

Posted By: Viper

Plus 8 capacity. - 11/12/19 10:08 PM

Confused.

When did the 4.6 come out?

I read that in 96 “it became an option”

Was it always an option over the 4.0?

What benefit if any did the 4.6 give?
Posted By: DaveW

Re: Plus 8 capacity. - 11/12/19 10:09 PM

Not much extra power but shedloads more torque.

I don't have the figures to hand just now!
Posted By: +8Rich

Re: Plus 8 capacity. - 12/12/19 12:19 AM

This is an exert from the Gomog site. The site also shows the 4.6 litre version but does not indicate performance specifications or details but the Morgan dealers list the 4.6's power at 194.4bhp with 260ft/lb of torque. This too is probably inaccurate and an appeal to Land Rover directly gives more plausible figures of 218bhp and 300 ft/lb.s of torque.

This compares to 190bhp and 235ft/lbs of my 3.9 Ltr,

I think about 1999 they were an option alongside the 4.0 I think till they stopped making the Classic Plus 8 2003 ish.

The main advantage being the extra torque.

There are a few MSCC members on here that maybe have access to more information.
Posted By: britmog

Re: Plus 8 capacity. - 12/12/19 02:55 AM

Richard: 5 years ago I tested my 94 +8 3.9ltr on a rolling road after a number of upgrades including fitting a Tornado chip and recorded 205bhp with 268ft/lbs of torque. Certainly enjoy the drive.
Posted By: Richard Wood

Re: Plus 8 capacity. - 12/12/19 08:23 AM

Originally Posted by Viper
Confused.

When did the 4.6 come out?

I read that in 96 “it became an option”

Was it always an option over the 4.0?

What benefit if any did the 4.6 give?


Check out Rover V8 engine specs here

The 4.6 litre version was introduced in 1996 by stroking the 3.9/4.0 engine to 82mm. This gave 225 hp and 280 lb-ft of torque, up from 188 and 250 of the 4.0.
Posted By: Rovert

Re: Plus 8 capacity. - 12/12/19 08:26 AM

Originally Posted by +8Rich


I think about 1999 they were an option alongside the 4.0 I think till they stopped making the Classic Plus 8 2003 ish.

.


The 4.6 was no longer available when I ordered my +8 in April 2002.
Posted By: +8Rich

Re: Plus 8 capacity. - 12/12/19 09:36 AM

Originally Posted by britmog
Richard: 5 years ago I tested my 94 +8 3.9ltr on a rolling road after a number of upgrades including fitting a Tornado chip and recorded 205bhp with 268ft/lbs of torque. Certainly enjoy the drive.

That was a useful mod Bruce.
Posted By: Viper

Re: Plus 8 capacity. - 12/12/19 10:38 AM

Thanks guys

So it was an upgrade option. Got it, now I know why I was confused.
Posted By: sospan

Re: Plus 8 capacity. - 12/12/19 03:52 PM

The Rover Plus8 finished in 2004 with a limited edition. The 4.6 wasn’t in many cars and I think it was an option but limited to availability/stocks of the 4.6 engine. There is a timeline document that I can dig out. It gives the evolution of various models and engines used. Will search on my stored data later.
Just looked in gomog and found some data.
Offered as an option 1997 to 2000.
Posted By: +8Rich

Re: Plus 8 capacity. - 12/12/19 07:22 PM

Timeline

I have it as a pdf if anyone wants a copy just pm.
Posted By: Luddite

Re: Plus 8 capacity. - 12/12/19 07:23 PM

From a very dull memory the rover V8 came in different compression ratios dependant on their intended use, which could be in a few different vehicles, I am unaware if they provided any special spec for Morgan...?

I had thought the larger capacity of the v8 came about as the result of emission regs and subsequent lean burn technology to clean it up, reducing power output thus Rover thought increasing cubic capacity was the way to restore power..? It seemed to me that the +8 became ever dependant on the cooling fan which tended to be almost constantly running when I was in convoy of Morgans and the fan on the +8 behind me was constantly running whereas mine did not come on unless stopped in traffic..

Some time back RPI seemed to be one of those businesses that specialised in the Rover V8, perhaps worth a visit to their web site..?

http://www.v8engines.com/homepageold.htm
Posted By: B3MOG

Re: Plus 8 capacity. - 12/12/19 09:27 PM

t[Linked Image]
Last year I had a 4.8ltr engine built and the dyno figures were 281bhp and well over 300lbs/ft of torque it pulls like a train and the fan only comes on when it is idling in heavy traffic.

David Byrne
Posted By: MOG 615

Re: Plus 8 capacity. - 12/12/19 09:45 PM

The 3.9 and the 4.6 Rover engine are the same basic design, but as Richard has indicated the stroke is longer on the larger capacity unit. Both are fuelled by the 14CUX (or Hotwire) Lucas system and the ignition is by distributor.

The 4.0 Rover V8 is a very different engine in many respects except the capacity (it is in fact a 3.9) , the crank journals are larger and the fuelling and ignition system are Lucas SAGEM (or GEMS)together with other upgrades this does make for a lot better torque than the 3.9 (BUT the revolving parts are heavier) . This later system was NOT fitted to the 4.6 engine.

As supplied by MMC the 4.6 engine utilised the same basic fuelling chip as the 3.9 as as a result the fuel mapping is anything but ideal , the motor runs lean (and therefore hot) and is generally rather poor in drivability. It benefits enormously from a Tornado chip, after which it will release something close to 210 to 220 bhp, it will struggle to hit 200 without it.

In theory the 4.6 will give better torque (after chipping) and therefore less need to change gear BUT the 3.9 will rev more willingly, so in many ways it is a unit more suited to a sports car rather than a large heavy SUV.

The 3.9 litre unit in Aero Racing Class B tune gives 255/260 bhp and it a hoot tp drive on the road. IMHO this is the best unit for a +8.
Posted By: Heinz

Re: Plus 8 capacity. - 12/12/19 09:56 PM

What do the experts think about the earlier 3.5 litre version but with injection and without a catalyst. My now retired mechanic was very enthusiastic about that engine, powerful, dynamic and rev willing he mentioned.
Posted By: Jacques

Re: Plus 8 capacity. - 12/12/19 11:28 PM

Here is the data sheet I have about the Plus8 Rover production.

Plus 8 Rover V8 - 3,5 L 3528 1968-1990
Plus 8 Rover V8 - 3,9 L 3946 1990-2004
Plus 8 Rover V8 - 4,6 L 4552 1998-2002

KR
Jacques from rainy France
Posted By: MOG 615

Re: Plus 8 capacity. - 13/12/19 03:29 PM

Originally Posted by Luddite


Some time back RPI seemed to be one of those businesses that specialised in the Rover V8, perhaps worth a visit to their web site..?

http://www.v8engines.com/homepageold.htm


Personally I would not recommend them for reasons that I not going to publish on an open forum.

John Eales , JE Developments, are both VERY good Rover V8 specilists that come with great pedigree and many satisfied Morgan customers. John Eales prepares all the V8 runners in the Aero Racing Morgan series.
Posted By: MOG 615

Re: Plus 8 capacity. - 13/12/19 03:36 PM

Originally Posted by Heinz
What do the experts think about the earlier 3.5 litre version but with injection and without a catalyst. My now retired mechanic was very enthusiastic about that engine, powerful, dynamic and rev willing he mentioned.


I am no expert , but as an owner who has modified his 3.9 engine I do have some experience.

The 3.5 has lighter reciprocating parts so it will rev a bit more willingly than the 3.9, however the torque figure will be lower. The +8s that were 3.5 with injection used the earlier "Flapper" injection, which is not as suitable as the later "Hotwire". I think the early cars had a cam that was particularly good in Morgan applications.

The 3.5 can indeed be made into a real flyer , just look at the historic racing +8s , admittedly they are on carbs rather than fuel injection , but they develop 250+ bhp and are street drivable (but perhaps a bit noisy?)
Posted By: Stephen888

Re: Plus 8 capacity. - 13/12/19 05:04 PM

I run a John Eales 3.9 on carbs. 20 years old. Last time on the rolling road in 2014 it was 284bhp. And that's perfect for me.
Posted By: Viper

Re: Plus 8 capacity. - 14/12/19 11:46 AM

Many thanks Guys.

I seem to have bought a 4.6. Very pleased. Didn’t realise they’re a rarity.

I bought it to use daily come rain or shine but I’ve ended up buying a perfect t specimen when I set out to buy a shed. Price spread is minimal on these cars. Makes no sense
Posted By: Viper

Re: Plus 8 capacity. - 14/12/19 11:54 AM

Originally Posted by MOG 615


As supplied by MMC the 4.6 engine utilised the same basic fuelling chip as the 3.9 as as a result the fuel mapping is anything but ideal , the motor runs lean (and therefore hot) and is generally rather poor in drivability. It benefits enormously from a Tornado chip, after which it will release something close to 210 to 220 bhp, it will struggle to hit 200 without it.

.


Who would you use to supply and fit this Tornado chip?
Posted By: Chris Cosher

Re: Plus 8 capacity. - 14/12/19 12:25 PM

Have a word with Mark Adams at tornado systems ltd. Cost me 430 pounds three years ago and it makes an enormous difference to the car .my 4.6 was almost undrivable before i fitted the new chip
Chris.
Posted By: Bjorn V

Re: Plus 8 capacity. - 15/12/19 01:29 PM

Interesting info. I own a-98 4.6.
My car has the Tornado chip, and has also had the ignition system changed.

According to this source, the Morgan 4.6 is not the same as the Land Rover 4.6.
http://www.gomog.com/allmorgan/40difference.htm
Posted By: Viper

Re: Plus 8 capacity. - 15/12/19 03:59 PM

Is the Tornado chip a DIY job?
Posted By: Rovert

Re: Plus 8 capacity. - 15/12/19 04:07 PM

For the Hot wire, I don't know.

For the Gems the 10AS will need resetting so unless you have access to good quality diagnostic kit such as the Rovacom, then no.

Edit Just spotted this but no details as to what you get over the base chip set.
Posted By: Luddite

Re: Plus 8 capacity. - 15/12/19 04:44 PM

B3MOG/David, that is one well polished and attractive engine bay. I had ever thought the flapper assembly spoiled things a tad. Though todat if you lift the bonnet/engine lid of an interesting machine all you see is acres of moulded plastic..!!!

Andy G I have never had dealings with RPI though their web site used to be interesting, I have no reason to doubt your thinking on anything Morgan including business ethics.. Thanks.
Posted By: B3MOG

Re: Plus 8 capacity. - 15/12/19 06:53 PM

Luddite, my car started as a flapper inj. but because of the problem with sourcing parts and tuning I decided to bin the whole lot including the ignition (distributor etc) it now has a fully mapped fuel and ignition ( Coil pack/trigger wheel) system and runs and ticks over perfectly plus it passes the emission test easily.

David Byrne
Posted By: Luddite

Re: Plus 8 capacity. - 15/12/19 09:18 PM

David, the first time I came across a hot wire system like yours was on a TVR that I was helping a pal to get it up and running again, I was pleasantly surprised by the miniscule size of the hot wire sensor and that it was housed in a very polishable alloy tube. TVR`s kit to fuel the Rover V8 seemed to work very well indeed, much less fussy than the flapper system too. No fear of the flapper being destroyed by a backfire either. thumbs
Posted By: teknome

Re: Plus 8 capacity. - 15/12/19 09:56 PM



Originally Posted by Viper
Is the Tornado chip a DIY job?


The hotwire ECU is the 14CUX. The mapping & program is contained in a PROM, such as a 27256, with 262,144 bits. very small by todays standards.. Some 14CUX ECU have the PROMs soldered onto the circuit board, some are plugged into a socket. If your ECU has the socket, then the original PROM can be removed (unplugged) and the Tornado chip can be plugged in as a replacement. I would think that most of the later ECU have the socket arrangement.

I don't have a Tornado chip, but have the Optimax chip, which originates from the same source as the Tornado. The arrangement is a circuit board with a PROM and decoder chip on it, this assembly plugs into the 14CUX ECU replacing the original PROM. I believe the contents of the Tornado and Optimax PROMs are encoded in order to prevent copies being simply made and used.

If your ECU has a soldered PROM it is possible to remove it and replace it with a socket, however it is a fiddly job with some risk. I have replaced a few, but it is not for the faint hearted.

While the PROM contains 262,144 bits, the program and data fits into one half of this store, and the other half is filled with a copy. More information can be found on Piston Heads via various historic threads by TVR folk

So the answer is 'yes' it can be a DIY job, with the caveat regarding the way the original PROM is affixed to the PCB
Posted By: britmog

Re: Plus 8 capacity. - 15/12/19 11:26 PM

For the 14CUX if you have the socket for the PROMS in then yes it is a DIY job to fit the Tornado Chip, if you don't have the socket then no. RPi Engineering will fit the socket if you need to have it converted.
Posted By: Viper

Re: Plus 8 capacity. - 16/12/19 09:41 AM

Wow techy stuff. wink

That’s for the info. It’s a 2000 registered car. I will check what I have.

Thx
Posted By: sospan

Re: Plus 8 capacity. - 16/12/19 10:16 AM

I read about the Tornado chip for Gems ecu. It can be done DIY and RPi give details on their website.
The Gems system is described as able to learn the engine/driving characteristics and there is a routine to follow to enable it to learn and reset itself. Fitting the Tornado chip is not difficult but sensible precautions are recommended. You earth yourself, remove the old chip, replace with Tornado then follow a setting up procedure.
I haven’t done it as I am ok with my set up.
Go to Gomog and have a read of the ecu system section in the Plus8 section. I have a printed copy of the Gems system for my reference. It explained the occasional management light coming on in the early days of ownership, of how the Gems detected and flagged up faults.
Just checked gomog and it has manuals for Flapper, Hot wire and Gems systems. Have a look and confirm which is on your car.
Posted By: teknome

Re: Plus 8 capacity. - 16/12/19 05:31 PM

Originally Posted by Viper
Wow techy stuff. wink

It’s a 2000 registered car. I will check what I have.

Thx


As it is a 4.6 I expect t will have the Hitachi Lucas hotwire (14CUX), the same ECU as the 3.9. The GEMs ECU came in with the engines labelled as 4.0. An easy way to tell is to check if you have a distributor. If it has a distributor, then it is going to be a 14CUX. The GEMS ECU uses coil packs which are driven from the ECU
Posted By: Viper

Re: Plus 8 capacity. - 17/12/19 04:50 PM

Well I am in possession of the car now.

It has indeed got the 14CUX jobbie

Booked in to BHM this Thursday to have the Tornado chip and diff centralising kit fitted.

Happy days
Posted By: Richard Wood

Re: Plus 8 capacity. - 18/12/19 07:57 AM

Originally Posted by teknome
Originally Posted by Viper
Wow techy stuff. wink

It’s a 2000 registered car. I will check what I have.

Thx


As it is a 4.6 I expect t will have the Hitachi Lucas hotwire (14CUX), the same ECU as the 3.9. The GEMs ECU came in with the engines labelled as 4.0. An easy way to tell is to check if you have a distributor. If it has a distributor, then it is going to be a 14CUX. The GEMS ECU uses coil packs which are driven from the EC



Just been re-reading "Morgan 100 years" the factory endorsed book. In 1998 the first +8's for many years were exported to the US with airbags and the stronger 4.0 engine with GEMS, as the latter complied with NA emission standards of the time.
Posted By: Chris Cosher

Re: Plus 8 capacity. - 18/12/19 09:54 AM

You will be also needing anti tramp bars on that
IMHO
CHRIS
Posted By: sospan

Re: Plus 8 capacity. - 18/12/19 11:10 AM

Will you get dyno readings before-after?
That would be good to see. Then the response when driving.
My 4.0l has a Panhard rod with Rutherford AVO shocks all round,LSD, brake reaction bars but no anti tramp fittings. It goes well and feels good.
Anti tramp could well be needed if you drive enthusiastically!
Posted By: Chris Cosher

Re: Plus 8 capacity. - 18/12/19 03:47 PM

I became seriously worried about the rear springs after doing chip and air filter etc .driving uphill round the dorset roads with a bit of power on had the rear springs jumping up and down in an extreme manner.
fitting anti tramp not only stopped that but also stops excessive sideways movement of rear axle . I also have a 3.9 ( in Sweden ) have never had the same feeling of pure torque in that vehicle
as the 4.6.

Regards Chris
Posted By: Viper

Re: Plus 8 capacity. - 18/12/19 07:13 PM

I’ll see how it feels.

I’ve not driven it yet but will take it the 5 mile trip to BHM tomorrow. Won’t really be able to compare before and after.

I’ll maybe put it on the rollers in the spring for fun

Will judge how the suspenders feel and go from there.

I’m fitting axle centralising blocks as it drives me bonkers aesthetically without.
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