Click here to return to the home page.
Classic Morgans
Who's Online
3 registered (Phil T, kankeL, The Austrian), 115 Guests and 19 Spiders online.
Key: Admin, Global Mod, Mod
Latest Photos
Southern Weather comes North
Island of Muhu in the rain
65 Plus 4 Four Seater back seat Lift-a-dot studs
Fuel cap seal
Touring Scotland with Anglemog.
Newest Topics
Rolls Royce Cullinan
by MJF
17/06/19 09:46 PM
Do you think I've achieved full penetration?
by Lowflyer
17/06/19 09:40 PM
"new" Top Gear
by MDS61
17/06/19 09:18 PM
Fitting wing beading to “sill”
by Phil4/4
17/06/19 08:10 PM
How reliable are current Three Wheelers.
by PaulJ
17/06/19 06:39 PM
Quarter Panel Protectors
by AndyA
17/06/19 03:26 PM
by DaveW
17/06/19 10:53 AM
Newest Members
arnieb, BradB, PANTHRO, MarsdenRobinson, M500
6524 Registered Users
Shout Box

Forum Stats
6,524 Registered Members
33 Forums
35,386 Topics
570,991 Posts

Most users ever online: 341 @ 11/02/18 10:30 PM
Today's Birthdays
Page 1 of 3 1 2 3 >
Topic Options
#573352 - 23/04/19 04:44 PM Turbo Plus 4 Plus -- final report
griffo Offline
Learner Plates Off!

Registered: 31/07/14
Posts: 453
Loc: Cornwall
Ecoboost Plus 4 Plus (final Report)

I must be setting a trend with "Possum", the turboed "Plus 4 Plus", since MMC have followed suit with their turboed Plus 6. Their yet to be announced new Plus 4 will have a turboed four cylinder BMW engine.
Possum’s rolling road tuning took place on March 20 at Stanton Motorsports (just off the M4) and went very well.
Possum had been carefully run in for 250 miles. All the instruments working fine, as per the standard car, and careful brim-to-brim tank measurements saw 31.7 mpg during test drives. Touring consumption seems to be around 36 mpg.
With minimum boost (0.4 bar) the engine already felt very pokey. On the dyno the boffins from MBE Systems progressively increased boost to a still-modest 1.0 bar with fuel map to suit and the result is pretty amazing. Target figure of 240 flywheel bhp was reached (more is available with extra boost) but the all-important torque figures exceeded expectations.
Torque curve is very flat from 2500 rpm to 5000 and peaks at 3000 rpm with 280 ft lbs (standard GDI Plus 4 only manages 145 ftlbs). To sum up, very driveable, loads of low down omph and no lag thanks to the advanced Borg Warner twin scroll turbo.
One major difference from the standard Plus 4 is the smoothness of the engine, which is also quite a lot quieter since the turbo acts as a slight silencer. With a high quality 200 cell EU4 compliant cat fitted the emissions have been judged “well within limits” and it will fly through the test, according to Possum’s local Morgan dealer (and MOT test station).
Having driven a few Rover-engined Plus 8’s over the past 50 years, “Possum” feels considerably quicker – and is much lighter.
The only downsides were self-inflicted. I fitted a new and rather fierce MX5 racing clutch and lightweight single mass flywheel instead of a standard MX5 clutch and the dual mass flywheel which came with the new engine. As a result it was initially a little juddery moving off from a standstill – this is hardly noticeable now since the clutch had bedded in. If doing it again I’d go for the standard MX5 clutch which should cope fine given the light weight of the car. Also, on the rolling road, we blew off a turbo boost pipe between the intercooler and the throttle body. This was because I had to shorten some of the alloy pipes to fit and they lost their “swage” on the ends for the Jubilee clip to snuggle behind. I found an inexpensive swage-maker on E-bay so all the pipes are now very secure and have the extra security of Jubilee clips lock-wired together.
So I’m a happy bunny and can’t keep the smile off my face. Icing on the cake was my insurers only asking a reasonable £130 a year extra for the uprated car.
Possum was ordered from new with a limited slip differential and I had already fitted a panhard rod. With all the extra torque anti-tramp bars were considered advisable to eliminate spring “wind up” and those nice people from New Elms provided a pair with machined stainless spring plates which are a work of art. I took boss Tim Ayres for a brief passenger ride in the car and he emerged impressed.
Several of you have asked about carrying out your own Ecoboost conversions on GDI or Duratec Plus 4s, or having one done. If so you need to contact Tony DeSciscio at:
Finally, “Possum” will be at the Prescott “Thrill on the Hill” on Sunday August 11th – see you there.

#573357 - 23/04/19 05:05 PM Re: Turbo Plus 4 Plus -- final report [Re: griffo]
Rovert Offline
L - Learner Plates On

Registered: 22/08/13
Posts: 153
Most impressive work.
Jersey & Spain (at least until the Brexit mess resolves itself)

#573381 - 23/04/19 08:48 PM Re: Turbo Plus 4 Plus -- final report [Re: griffo]
rid967 Offline
L - Learner Plates On

Registered: 24/08/15
Posts: 204
Loc: West Dorset
Amazing and courageous journey. Thanks for sharing. Fabulous car and quite unique. If only the ARP4 had been like this!
3.7 Roadster
Porsche 964 C2
JCW Mini Cooper S Cab
BMW 1200 GS
+4 4 1995-2002 / LM 62 +8 2002-07

#573383 - 23/04/19 08:57 PM Re: Turbo Plus 4 Plus -- final report [Re: griffo]
deano Offline

Charter Member

Registered: 12/02/12
Posts: 5376
Loc: Taunton
You well and truly should feel a happy bunny, congratulations.
Martin (Deano)

#573396 - 23/04/19 10:27 PM Re: Turbo Plus 4 Plus -- final report [Re: griffo]
Gambalunga Offline

Member of the Inner Circle

Registered: 03/09/11
Posts: 11321
Loc: Mandello del Lario, Lake Como,...
Well done. I only wish I could do something similar.

Torque and power figures like that would be supurb in the new "Plus 4" or whatever they decide to call it. More power would become much more costly in Italy and it is the midrange torque that really counts anyway.

#573402 - 23/04/19 11:03 PM Re: Turbo Plus 4 Plus -- final report [Re: griffo]
Heinz Offline

Talk Morgan Addict

Registered: 07/09/09
Posts: 3841
Loc: Cologne, Germany
Well done Griffo! Your Mog is one of a kind. I have rent a 2.3 Mustang in the States and I can confirm that the twin scroll technology is a very good step forward in turbo development. Your car must be amazing. She combines the very Trad concept in combination with a modern engine which is unique. We will see similar engines in MMC future but in combination with a „modern“ car suspension which is not a bad story on its own but you have realized a phase which will not be duplicated any more.

#573417 - 24/04/19 04:32 AM Re: Turbo Plus 4 Plus -- final report [Re: griffo]
auster Offline
Has a lot to Say!

Registered: 28/03/15
Posts: 1018
Loc: Vienna Austria
Congratulations on your achievements with this car; most impressive. Also many thanks for such excellent reporting of the journey and destination. I'm sure you are inspiring others.
1968 4/4 1600
1950 Auster J5B
Kitfox S5 Outback
Jodel D9
1988 Peugeot 205 GTI 1.9

#573425 - 24/04/19 07:56 AM Re: Turbo Plus 4 Plus -- final report [Re: griffo]
Richard Wood Offline
Talk Morgan Enthusiast

Registered: 03/02/16
Posts: 1703
Loc: East Harling, Norfolk UK
Great info Griffo, you must be over the moon that all the sweat and tears have paid off.

Given the better than expected torque, how do you feel about the standard MX5 box taking it? I believe the six speed version is stronger although you probably don't need the extra ratio.

The cars light weight will help of course. Many years ago whilst building a Cobra replica with a big valve Ford 351 V8, I was told not to worry about the relatively weak ZF gearbox mated to it as the cars light weight would not allow the full torque through it - traction would break first wink

2018 Roadster - Red/Magnolia - "Morton"
1967 Land Rover series 2a SWB
1960 Velocette Venom

#573429 - 24/04/19 08:26 AM Re: Turbo Plus 4 Plus -- final report [Re: griffo]
DaveW Offline
Roadster Guru
Member of the Inner Circle

Registered: 11/12/08
Posts: 17430
Loc: South Yorkshire
Amazing job. wine
2005 Corsa Red Roadster S1
2016 Saffron Yellow (Narrow) Plus 4

#573435 - 24/04/19 09:16 AM Re: Turbo Plus 4 Plus -- final report [Re: griffo]
griffo Offline
Learner Plates Off!

Registered: 31/07/14
Posts: 453
Loc: Cornwall

"how do you feel about the standard MX5 box taking it?"

Hi Richard,
I did have some worries on that score but Westfield Cars (who use the same ecoboost motor mated to the 5-speed MX5 box) said they have had no issues, even in track versions boosted up to 300 bhp. Apparently the latest iteration of the Mazda box is much stronger than earlier ones.

Page 1 of 3 1 2 3 >

Moderator:  Aeroman, Boshly, Simon