Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) A view on GDI engines

I'm currently investigating a possible change from a 2012 Duratech powered plus4 to one with the new engine.

I stumbled over this article http://www.thetruthaboutcars.com/2012/05/ask-an-engineer-gdi-problems-in-a-nutshell/

Given posts flagging up possible issues with the siting of catalytic convertor giving rise to excess heat generation I'm starting to think it may better to sit on my hands for the time being and see how this new engine pans out.

Any views?

See the other thread on here on exactly that topic
http://www.talkmorgan.com/ubbthreads.php...ng_issue#UNREAD

I'm not exactly sure why you would want to let go of your plus 4 duratec which is a much more flexible engine in that there are lots of modifications possible to add power whereas the GDI has no modification possibilities at all ! Whats wrong with your duratec ? No overheating on duratecs either !

I am totally in agreement with your posting. I have had 3 +4's two of them with Duratecs and they are the best, easiest to live with and totally superb engines. Just my opinion but I would not go for a GDI, no disrespect to those that have one but one look at that intake trunking passing right over the catalyser (put right next to the engine to heat up quickly and meet the tighter emission requirements where HC measuremt is taken sooner after start up so not MMC fault) it's obvious that the incoming air is going to be heated. I am sure a cool air induction kit will be available PDQ but the layout at the moment is not good. The Duratec pootles around all day at excellent MPG or can be made to go like stink and all the development is out there as almost off the shelf bolt on goodies. As you can imagine I am a Duratec fan and had 2 road cars (still have one of them) with Duratec engines.

I have posted some time ago about the pcv ( positive crankcase ventilation) issue with gdi engines. The Morgan being an n/ a engine has no need for a PCV valve in the vent pipe, which runs from the cam cover, so I have just run it to atmosphere and plugged the hole in the inlet manifold. That at least solves that issue and hopefully only running on high octane Optimax fuel or similar will alleviate any other problems. The only scope for tuning may well be replacing the nasty manifold/cat setup with something better incorporating an expensive Euro 4/5 E-market 200 cel metal substrate cat.
Hey ho

Agree. Isn't GDI there simply to keep the European legislators happy (better emissions performance on cold/short cycle). It's not there to make drivers happy. Ask an Audi RS4 owner how much they pay each service do get their exhaust valves de-carbonated.

I am puzzled why Morgan changed the engine for the Plus 4 unless it was for supply reasons (though Ford will still happily sell Duratec crate engines to anyone else). Shame on MMC if it was simply to give customers "the latest shiny thing" - I thought they were above all that mainstream car-maker piffle.

Totally agree with your analysis of the Euro immissions nannying etc !

"Shame on MMC if it was simply to give customers "the latest shiny thing" "

Hmm, it seemed to work for me.................

Gentlemen

Thanks for the input.

I think I'll go and have a lie down and let the thought of a change pass.

I'm finding this thread an interesting read and now doubting my understanding of precisely what the +4 engines are. Is the new GDI a new engine based on the Duratec body (the 'old' engine being a Duratec DOHC L-4)and therefore still part of the Duratec family - ie it appears the same from the outside but the majority of the innards have been modified and it has direct injection. Is it's full title a 2.0 Ti-VCT GDI L-4 as used in Mazda? Puzzled now .....