DOHC engine of Ford Sierra

Hi, I am currently going through courses on engine building and I would like to know what could I expect from the 2.0 DOHC engine (and DOHC engine generally). What are the differences from the classical engine? Any tips if I were to dissemble it, clean it, balance it and assemble it once again?

Thank you a lot!

There were at least two different DOHC engines used in the Sierra, exactly what do you have? The classic Cosworth has a lot of potential, but the other(s) are basically orphans with no real options other than custom work.

Unless you have a known problem, such as a knock or excess cylinder leakage, a simple strip, clean and re-ring/valve grind is unlikely to improve anything significantly.

I would start with a full service, especially if it has an unknown history, including cleaning the MAF, replacing all filters, HT leads (if used) , etc.

Hi, thank you for your answer,

I might be getting the 1992 Ford Sierra 2.0 DOHC.

There is not any problem with the engine, not any I am aware of, as of the car, I might be adjusting clutch a little bit. What I am a little worried about is the that the engine might be messy inside and therefore not work as expected. I am worried bout it coz of style it has been driven for 5 years, it has been kept on super low rpm and than not started for another 5 years.

I don't know if i will be dissambling it, a little rev and 100 oktan engine might be just enough.

But still I am interested in what is different with my DOHC apart from the engines explained in these courses"engine building" and I would also be interested in any tips and tricks for DOHC.

Thanks a lot for your answer and have a nice day.

Francek Jakub

I'm pretty sure you're going to have the N8/N( DOHC engine, available in 8 and 16 valve versions. It's been a VERY long time, but I think the only other vehicle sold, in the UK at least, with them was one of the Escort models, and in either case just for a very few years because of the engine not being very good compared to the other options FORD had - being tall, heavy, and not that powerful.

You really need to identify the engine to know exactly what you're going to be working with, but I think you're going to be limited in the mod's you can make, if it is this engine, as even at the time there really wasn't any aftermarket support.

Personally, if the vehicle's in good condition, I'd probably leave it stock, give it a full service, and maybe replace the dampers and tyres with better options to allow smoother cornering and more efficient cruising/touring/general driving. Oh, and a more modern head-unit and speakers.

Thinking on it, I seem to recall some Group A, stuff being avaialble from Ford AVO for the Escort but, again, it's been a long time.

Hi, sorry for not specifying enough, but I do not have much more information, all I can do us drop some photos about how it looks like - both engine and outside of car.

Thanks a lot for your patience.

Hi, sorry for not specifying enough, but I do not have much more information, all I can do us drop some photos about how it looks like - both engine and outside of car.

Thanks a lot for your patience.

Hi, sorry for not specifying enough, but I do not have much more information, all I can do us drop some photos about how it looks like - both engine and outside of car.

Thanks a lot for your patience.

That seems to be the basic engine I was thinking of, if you look inside the oil filler you may be able to tell if there are two lobes on the exhaust camshast for the cylinder below, or just a single lobe.

The other thing is the engine/chassis plate information, if you can find it, it should identify the specific engine model, or give us more to work with.

I'm sorry I can't be much help, I'm mostly working off memories of press releases of the engine on release, and a CC&C article - more likely to be Group N, thinking on it, and it's been quite a while so details are hazy.

Seems there are still parts available -

https://www.burtonpower.com/tuning-guides/tuning-guide-pages/ford-dohc-i4-sierra-tuning-guide.html?product_area=Engine+Components&srsltid=AfmBOoqLqYLG2snrldOoeWE6d_OE4tSk2d6kDR5W9hX4od01M8bE9TQC

http://www.atss.planet.ee/kolaladu/ford/Scorpio/DOHC/dohctuning.pdf - discussion on the engine(s) and tuning guide 👍