ENGINE MODS XANTIA PETROL

[Harry1975]

I have an Xantia 1.8 16v. just done the head gasket and new idol speed sensor and boy its made a BIG improvement ! but have no idea on how to get more power out of her, or any mods that can be done to Xantia petrol engines. I did take mine to be tuned a few years ago to a boy racer garage, but they told me there was nothing they could do. TBH I think they could not be arsed as it was not a scuby ,evo or an saxo. Any advice, tips, links i would be most grateful
Thanks Harry

[Deanxm]

The trouble with any normaly aspirated engines is that to gain more power any changes have to be made to the engine itself, higher compression, increased displacement and better breathing are all time consuming and expensive things to do, your almost always better off just buying another engine or leaving it alone as you can really spend some money with little gain.

D

[Harry1975]

ok thanks for the advice

[Deanxm]

there are things you can do to sharpen throttle response but that always involves making the engine noisy and less refined, you could see about a chip but tbh you will only see about 10bhp at a guess.

D

[Harry1975]

yeah i had wondered about that. Im thinking a good exhaust system and a fuel pressure increase . Though as she is now she goes well i get 0-60 in 8seconds not bad for a big old 1.8 xantia, it does p**s the boy racers off the lights in there saxos lol

[Deanxm]

an exhaust and upping the pressure for fuel delivery are things you really want to do after increasing engine breathing with porting or cutting the valve heads that sort of thing, there is no point adding more fuel or making the exaust bigger if you have not made changes to allow the engine to process more air and fuel therefor creating a higher flow of gas through the exhaust.

If you want the most power from her i would get some good plugs gapped up right, get a new fuel/air/oil filter on it and if you want running a slightly thinner oil will increase power at revs noticably.

D

[ashy90]

No chance a Xantia 1.8 will do 0-60 in 8.0 seconds. How are you timing that?

[addo]

Not buying into that contest, but I recommend the following for our man:

http://www.holley.com/07005NOS.asp" onclick="window.open(this.href);return false;

Bit of pillarbox red on the supply bottle, couple of "Quell" stickers from a vinyl sign shop and Mr Plod will be none the wiser - after all, having a fire extinguisher in the car is sensible!

[Harry1975]

it does do 0-60 in 8 seconds, ive timed it so has the mrs and mates its a 16v, im not talking s**t she will hit 60+ in second gear, though i do change it to 3rd before. it all in how you drive and get it off the start

[Timmo]

due to being the 1.8 mods will be rarer for it, a chip will make a little difference If using a Proper one, but! so many fakes about chances are you'll do more harm than good! a free'er flowing exhaust will see the rev's happier higher up but chances are it'll have tio be a custom job, as the 1.8 isnt the most popular of engines amongst the modders, especially in Xantia form!! you May find some cams for them, based on the 406 lump, and vernier pulleys will allow you to get the Best optimum out of the engines timing, but will be costly to set up as best results are found on Rolling road runs and minor tweaking,
you may find some small increases through fitting some Good quality plugs and leads to give a stronger spark, and also worth going through the engine earths and cleaningi them all up, petrol lumps like a good healthy spark,
you could go down the induction kit route too if you fancy, but you wont see any real world gains other than the Sucky noise that they produce, most people Feel the cars Much better after fitting them, but on the whole, unless your engines suffocated by the inlet system, it'll loose mroe than gain! most breathing and exhausts on cars are tested at the factoriesd for the optimum longevity of the componants and performance of the engine over its lifetime, the one excpetion here was with the saxo vtr mk2, Citroen strangled the engine a smidge on the intake side to allow for a bigger gap in performance temrs between the R and S models, a Good induction kit on the R would free up close to 10 bhp!
a few of the guys in the 16v club (bx) have done some indepth research into the engine details and flow rates etc. most tuners would say Dump the air flow straight away, yet on a flow test the afm is good to 190 bhp before it becomes restrictive, the fuel pressure regulater on the fuel rail is also more than capable of supplying enough fuel for the high 180 bhp's before it needs tweaking, same story witht hew throttle body, you can polish them up etcd. but wont see any difference in real terms,

if its actual usable performance you want then the C5 steely wheels are remarkably light as they come, hal the weight of the std alloys! a set of them with decent tyres will see the handling transformed into a more direct feel, (providing the rest of the suspension compnants are up to it, arb bushes, links, bottom ar bushes etc.) reducing rolling weight is a big factor in how a car performs, in terms of a Mountain bike, removing 1lb of weight of the wheels is equivalent to 3lb from the frame!!

also worth getting your speedo checked for calibration, it'll more than likely Indicate 60 in second, but i'd very much doubt it'll do such, in the bx16v, to get 60 in second youve got to raise the rev limit up to 7800rpm, and then its just about on it!
i know my bx runs at 6mph over read, tested with several gps devices on long straight Flat roads driving a series of steady speeds, dropped to 1.5mph over read running on 17's, but the way i drive it, it Ate botom arm bushes every 6 weeks! is quite amusing when you travel along at a True 70mph and see just how many cars you pass!!!

the end of thew day, and please dont take this wrong, its a Xantia, it was never designed to be a rocket ship, you could throw a Lot of money at it and not really get very far, and as its an old design, your not aso likely to find tuning companies prepared to produce parts for it!

[Xantidote]

Perhaps Harry enjoys the "Wolf in sheep's clothing" bit, when joining the Traffic Lights Grand Prix

[addo]

I've not confirmed, but it looks like you can't fit a GTi6 exhaust without reworking it, because of the firewall "shelf" that carries fluid lines to and from the doseur. This would be simple enough to repipe with the motor out - and thus trim the shelf away - but I suspect Harry is looking for easier gains!

Peter T, the Australian enthusiast well-known on 205 forums, can arrange a reground inlet cam for not too much - or you can get a new one from several sources. Mild ones will cope readily with the existing ECU's limitations and the slightly choked aspiration.

Flogging a Xantia hard, is harsh on the P-bushes. I can say this confidently from experience!

[Harry1975]

Wolf in sheep's clothing, you have got it in one, i love the looks on their faces, as Xantia's are not known for being fast thanks for the advice gentlemen, happy driving

[Harry1975]

P-bushes ???? thanks guys you have answered what i wanted to know. I will leave her as she is loved and well looked after ,well mechanically lol . ive just done drop links, hub ball joints, wishbone boots. anti roll bar boots, new cat exhaust , oxygen sensor, new break caliper ,head gasket and blots,new spark plugs, new LMH fluid ,heater matrix, glycol in the water,new O rings in power steering pump and cleaned all the earths .All and all the full works, spent about £300 on her, did all the work myself as i can (thank god!) I was given her 4 years ago for free with 97000 on the clock now 122000, ive spent about a grand on her in that time, so i think ive had my moneys worth out of her

[Ratheram]

Look on my post in the "Introductions". My xantia 16v is rather got at. Ive got experiance with Citroens and my mates dad has garage converted into a machine shop. In his previous work, hes built Minis with 16v heads, made spaceframed minis and bike engined minis so hes pretty clever with it all. If i were you, ild leave the ports. Dont gas flow them!! They are huge for what they are and dont need messing around with. Mine, we made a PTFE gasket to fit perfect for a gas flowed/ported Xsara VTS inlet manifold and then chucked a couple of studs in the head, put the gasket on, see where the head didnt sit right and took out any restriction so its perfect flow. Dont "mirror finish" or polish anything where the air goes in. It needs terbulance to mix the fuel vapour and the oxygen going into it. The XU10J4R in the Xantia is the same block as the XU10J$RS as the Xsara VTS/ 306 GTI6 so would be an easy swap. Im yet to get around to putting the VTS exhaust on my xantia, Ive got 1, I will have a bash later in the month to fit it. I have had my cams reprofiled at KENT CAMS to a "PT81" profile. I dont believe its a too agressive profile, it gets it going much quicker. If you go for brand new cams, there have been horror stories where the lift is too great and contact has occurred. I have also read that the inlet cam is the only 1 that would need changing as the exhaust is fine but both inlet and exhaust cam are the same and while they were out, might aswell do both... The "Cats" are crap. Melted 2 now, both genuine... They cant cope with the load and yeah, I guess it could be restrictive at high speeds but under 90mph, I shouldnt bother cutting it out.

With fuel injection, my Xantia has a "self learning ECU" but yes, to cam it and tweek it it does need a remap. Unfortunatly mine has a crappy map that gets it going but needs a rolling road and proper setting up. Every engine is unique. DONT uprate the fuel pressure unless you want to melt your pistons. Simples. Whatever you do to a fuel injected car, to an extent it would learn there has been a change but it would run leaner/richer. No point chucking bigger injectors as it would inject the same ammount of fuel. No point putting an induction kit on it as it would only take the right ammount of air. Same with exhaust. If you do though, get a replacement panel filter from K&N. Ran 1 for a while, made a lil improvement I think but all induction/free flow exhausts, you just spent soo much on something that "makes it quicker", you put your foot down, it sounds louder so acts as a placebo. It isnt quicker. You just look like a chav.

To get a xantia sweet, full service, new plugs, wishbone bushes and a good wash and polish. The other option, spend £1000s.