Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) 4/4 Sigma re-map

Ooooh yes please !!!

Had mine re-mapped by same guy about 3 years ago now.
Good points.
Engine much more lively
Peak torque comes in about 500 rpm lower but is better at lower rpm than original.
Petrol consumption basically no change, slightly better on a long motorway run.
Bad point
Well not really, power drops quite dramatically around 6800rpm which does not appear to be the Rev limiter. & slight tendendance to just pink around 3000rpm so Shell’s V power is a must.
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Mine has a different diff ratio too. The combination of the two makes the car an exiting drive. I still find the engine comes “ on cam “ just over 4000 rpm but pulls well from 1500 rpm.
I would recommend the re mapping as the engine seem “happier”

My remap is without any pink, it is individually tuned to my engine at the rolling road. May be I did not reach 100% but 95% of what is possible but the ECU is still able to change the mapping due to the knock sensor.

I had my 2014 4/4 remapped by Cain about 2 years ago and like other posters I was immediately impressed by the change in acceleration and a distinct improvement in mid range torque.

As reported I experienced pinking but went to super unleaded which cured that and gave an extra buzz.

The 4/4 is a car to drive hard through the gears and with my remap it pulls right through to 6900 rpm without drop off.

After the remap and on a solo drive to Venice I continued to achieve 40+ mpg.

I then went on to fit a Librands manifold and sports exhaust for further improvement.

In its present state the car sits at 139.6 bhp (up from 110bhp).

No downside to remap !!!!

My dilemma:
continue to develop a car I have had from new which has proved to be reliable or.... I am currently besotted with the 2011 Supersports "package"!!!

I dare not go for a test drive in a Supersports just in case I betray my black beauty !!!

My feelings for the Supersport is that I would have to keep it in its standard trim as a limited edition and by nature I like to modify/improve/change my cars.

Anyway I have just re taxed my 4/4 and the first MOT is due 1st Nov with a service.

Meanwhile I will investigate further engine upgrades ..perhaps through the Caterham fraternity.

Waiting for Cain to come up with an engine conversion for the 4/4

Come on mate ...pull your finger out !!!!

I disagree about keeping a car in original condition. About the only thing I would say would be keep all the bits so that it can be put back to original if it ever becomes an issue.

Every Morgan ever built is different to the next so making a few little extra changes is not going to make much difference

If I had a Plus 4 SS I would still get the SSL suspension front and back though I would ask for the next higher spring rate for a more sporty than touring ride.

I have fitted the higher rate rear springs and I am very happy with them and I am sure that the lowest rate from the race kit (slightly higher than the road kit) would be effective on the front of a car like the Plus 4 SS. I think it would reduce the body roll, already better than stock with the road kit, and make the steering a little sharper with the correct toe in and camber adjustment. If my experience with the higher rear rate is anything to go by the loss in comfort would be minimal and barely noticeable.

There is a lot to be gained from a good tuner. My 89 Plus Four produced 156bhp at the wheels after Mark Adams and Omex worked on it and that was with the M16 engine which bar room boys would say was not tuneable. Cain and Williams must know what they are doing and I am glad to hear that people can be so pleased with the results.

p.s. Still learning the new Roadster as 10,000 miles comes up. Planted, no bottoming out very quick but surprisingly frugal.

Meabh, you are driving a 3.0 Roadster? One good „tuning“ is to fuel 98 octane. If you experience it the first time it is very noticable.

I don't know that much can be done with the GDI. Perhaps a slight modification to the lambda settings or the ignition map would be possible. The GDI uses a very complex system of injection that lays down micropulses of fuel in the cylinder in order to achieve the correct distribution of fuel in the air as it is drawn into the cylinder.

One way of achieving this (purely conjecture) could be a black box which modifies the signal from the sonda lambda sensor in order to modify the fuel to oxygen ratio. This system has bee used with success on fuel injected motorcycles. Since the signal from the sonda lambda (O2) sensor is used to control the amount of fuel the engine gets it is a fairly economical mod.

Of course it is quite illegal to tamper with the anti polution equipment of road vehicles so one would only use such a modification on the race track

Thanks Heinz, I do always use 98.

Any info about the Sigma please ask, as some may know I have quite a lot of info and experience on this engine.

I use this engine in my Morgan race car & in Caterham race cars.

Look here for proof

https://www.youtube.com/channel/UC8O1xn0j2z0Pz_hE6TMZ9kA