Xantia XUTD Tuning - Effects

Chrispy · Post by **Chrispy** » 12 May 2005, 19:12

See here for what he says:
http://www.zen19051.zen.co.uk/Mechanica ... tuning.htm

capri_tzd · Post by **capri_tzd** » 12 May 2005, 23:25

Thanks guys, might look into this [:)]

Kowalski · Post by **Kowalski** » 13 May 2005, 04:19

How can getting more power out of an engine cause no more stress? If its doing more work, it's under more stress. Perhaps, what Gav @ Dervdoctor should have said was that the power increase was within the amount of stress the engine would tolerate... it'll tolerate any amount of stress you put it under for a limited period and no longer.

jeremy · Post by **jeremy** » 13 May 2005, 11:41

I entirely agree! If this was true why have the 1.7TD's got different rods, pistons and oil pumps - if the there was no extra stress these parts wouldn't be needed.
Jeremy

rossd · Post by **rossd** » 13 May 2005, 12:48

Granted, but look at the 1.9 MI16 engine. 160bhp and about 130 lb/ft torque, only slightly behind the 1.9 td in terms of torque output but way ahead in the power stakes. Its revs to oblivion and is built out of tin foil when you compare it to the TD. Granted you have to build a TD that bit tougher, but the XUD is built with such a huge margin built in that the 15 - 20 bhp a tune up does really doesnt affect reliabiliy. I ran my 'tuned' 306 past 150K miles in its tuned state, with another 100K in it, which I know is nothing, but I know of a 1.9 N/A which is a friends car and it is absolutely ****ged at 110K. Granted, slightly more stresses will be on the engine if tuned, but look after it and service it regularly and it will still go on for ever and ever when compared to a totally standard example. Its odd how I have seen many TD's go on longer in mileage terms than their NA equivelents.

Chrispy · Post by **Chrispy** » 13 May 2005, 13:23

Yeah, my old 405 NA was buggered at 90k. Smoking, flat, burning oil, back-pressure, the lot. My other 405 GLX TD (that my dad now has in France) is still going strong. Admittedly it has had a new cylinder head cos my dad had a radiator leak, let it run dry, cooked it and warped the head. But, bottom end wise it's fine.
As you say, the Turbo'd engines are beefed up anyway to handle the extra stress. I'm sure that the extra 22 - 26 BHP are well within it's tolerances. 90 BHP is probably at the bottom end for maximum reliablity. Lets face it, anyone of you lot been to rural france? It's all old manky Pugs and Citroens. They never service the damn things and throw em round those country lanes, usually a bit tipsy after a bit too much Pastice and they're still going. For us British lot who are good to our cars with oil and filter/ coolant changes etc, I'm sure 22 - 26 BHP will make not a jot of difference. Also the HDi's share many of the bottom end components with the XUD's. These are pumping out 110 bhp in high end form, and even 130 bhp in Mondeo form with a 16v head, simply re-labelled TDCi (PSA have their finger in so many pies).

Kowalski · Post by **Kowalski** » 13 May 2005, 16:44

The 1.9 MI16 can't really be compared with the 1.9 TD, the TD has a much higher compression ratio (almost double that of the petrol), the TD has to be made heavier to cope and to last for 250k without needing a rebuild.

jeremy · Post by **jeremy** » 13 May 2005, 17:38

Have a look at the Allard site - they publish a book on the subject, graph priced bits and will even do the work for you at what seems a very modest charge.
http://www.allardturbosport.co.uk/
Jeremy

Kowalski · Post by **Kowalski** » 13 May 2005, 20:26

http://www.allardturbosport.co.uk/pages ... ions.shtml
Magnetic fuel ioniser. .. £42.54
That says it all.