Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) EXHAUST FUMES?...

I had the same problem with my plus4 that has the supersport MZR/OMEX engine (200bhp).Problem was solved by chopping a couple of inches off the existing tailpipe and sliding on a 45 degree mandrel bend in stainless steel (polishes up nice) over the remaining tailpipe. The bend should be orientated outboard and upwards at about 2 o clock position. You can source from exhaust parts uk for about £15, you should be able to get the correct internal diameter to facilitate a nice sliding but tight fit, can't remember the diam but can measure tomorrow.

Lowflyer...sure we have met at Newby Hall or some North Yorks car show ?

I like your solution...although I seem to have solved my fume issue would welcome any pix of your system if possible.

It would seem there is a Supersport out there with a side exhaust..would like to see that option.

Trying hard to keep car standard (difficult!!!)..just drive the thing !!!
Had it a week and done 950 miles (!!!) getting used to it I'm sure I will settle down soon !!! (maybe not !!)

Almond Tart

Wow Kev that is some mileage, great it is being used, how many miles has yours done?.
The 1st owner of mine only did 250 miles in 41/2 years such a waste, I have done more than that in a week, I even had it out yesterday it was bloody cold though.
I was due to take it to Brands Hatch Morgan’s today but snow on the ground means I wimped out.

Yes we have, i think it was at Ripon race course, i had the old 7 there.
My solution was to fit a 45 degree mandrel bend s/s, 57.15 OD 54.15 ID, i used a stainless steel clamp to secure this to the existing shortened tailpipe which was 54mm OD. I then fitted a suitable length of 60mm OD stainless steel tube onto the end of the mandrel bend. The 60mm tube was a good tight fit over the end of the mandrel bend. You can rotate the mandrel bend to get the right height and orientation for the exhaust exit. Mine is elevated to be a bit closer to the underside of the rear bumper than standard and when viewed from the rear the exhaust exit is about central with offside rear tyre. All bits available from exhaust parts uk online.
The side exhaust sounds a bit drastic and expensive, unless you feel confident about getting the Dremmel out and chopping a bit out of the wing yourself. Mind i do find the clatter from the throttle bodies enough soundtrack without the addition of a side exhaust.

P.s wish i could post photos, I'll try again

Morning Steve

Mine has done 11500 miles to date.

I have the mileage at the various MOTs over the years and some owners hardly used it...such a shame but good for me I guess.
Yours at 1700 miles when I saw it!!!..they are better for using...drive it like you stole it !!!

Lowflyer..thanks for info. If issue happens again I like your solution.

Almond Tart

This is so sad.

I have the same exhaust.

Firstly it is very important that your car has the revised calibration from Omex in the ECU. Without that the fuel air ratio will not be correct. There were a lot of complaints from owners before Omex, in conjunction with Williams, developed a new calibration.

You may also like to read my post on the catalytic convertor and how I resolved a similar problem after about 50,000 km on the original cat. I came to the conclusion that the original cat was inadequate and I am very happy with the replacement.

http://www.talkmorgan.com/ubbthreads.php/ubb/showflat/Number/500409/

Kev,

Interested to see your post and your experience reflects mine exactly with the same P4SS. Your car had the latest software from OMEX (at least it was the latest version at the time that I traded it in at Mike Duncan's back in 2017). The latest fuelling or calibration from OMEX is not brilliant (especially on cold starts and warm up) but its good enough. The original calibration was poor but I presume OMEX didn't have the final spec hardware when they did that calibration. That however is not the root of the issue, nor is the location/direction of the tailpipe outlet that significant either.

The key to the problem is the exhaust gas after-treatment system and the fact that the catalyst 'drops off' in terms of temperature when the car is under a light load. Simply put, at lower temperatures the catalyst is not converting unburnt HC in the exhaust gases very effectively (HC is the key because that is the constituent that you can smell most readily). This dropping off is quite an unusual phenomenon in the automotive world and rarely experienced in other cars. When I had your car there would be no fumes when the catalyst had fully warmed up and the car was being used under high load or high rpm (better to be both!). When slowing down for a speed restriction, like entering a 40 mph zone for example, all would be fine but after 30 seconds or so you would suddenly start to smell the fumes. This smell would continue when speeding up but would then disappear after some time at high speeds/loads. The problem of the act temperature dropping is exacerbated by the low mass of the P4 which means it can be driven on just a whisper of throttle at lower speeds - leading to low gas flow through the cat and it loosing temperature.

Drive it like you stole it (as I think somebody posted above) is one solution or you could try something like exhaust wrapping to try and keep the exhaust gases as warm as possible before entering the cat. Be careful with wrapping as some wraps are not compatible with stainless steel so the spray-on/bake on ceramic coatings are better (but much more expensive). Needles to say the catalyst itself dosen't want to be wrapped!

I think Gambalunga is also on a right path by finding another catalyst. A different wash coat on the matrix (internal parts of the cat) may increase conversion efficiency which will keep the temperatures up. The problem would be to know what works and what doesn't and trial and error would be involved.

So in a nutshell - calibration, exhaust outlets will have marginal affect but the real solution is keeping the catalyst hot. That's why you need to do the MOT emissions test immediately after a good high speed run!

Thanks Ian

I have come to the same conclusion and whilst the fitting of a missing exhaust clamp has lessened the issue the cat temperature is critical.

Its not a big issue as I enjoy the car so much and have just returned from a 5 day " spirited" trip to Holland.
It starts from cold in minus temperatures on the button,settles down to an even idle and pulls like a train...can't be much amiss with its setup !!!

FYI
Your car SS04 MOG belongs to SteveLoc on here..My car V4KFH has over 11,000 miles on it ,same colour(but white roundals) and had ECU update last October.

Confusing ?..you never see Supersports then 2 come along in the same colour!!

ALMOND TART

Thanks for clarifying the identity of your P4SS. I get easily confused these days, must be all those exhaust fumes!!

Almond rules as far as P4SSs are concerned (just my humble opinion and I confess to being biased).

Envy your trip to Holland and bet that was fun/bracing. I've got a couple of Euro trips planned this year for the ARP4. Can't wait!