CT Turbo engine and gearbox FS Low Miles

[Xantiaman]

I have in my garage a low miles (65k) XU10J2TE engine from a S2 Xantia Activa, which is the same lump as fitted to XM's.

I bought it as a whole because i needed a good turbocharger/manifold for mine, and the recently fitted clutch. Its looking like my manifold is actually ok and its just the manifold gasket that has died, so i now have this surplus to requirements.

As mentioned, its done 65k with FSH, i have a print out with all the oil changes in its life. Its of 1999 vintage so has a plastic inlet manifold and other minor detail changes but the engine should be the same. The gearbox being an ML5 should also be suitable for an XM.

I paid a good price for the unit and although i wont fully recover my costs, it is a sought after engine with such low miles. My turbocharger will be included in the sale if needed, its whisper quiet and gives good boost from 1500rpm despite a blowing gasket!

I am after £200 for the engine and £100 for the gearbox. I will consider any offers. Delivery also available at cost of diesel for my van.

I am often on the FCF under the name of Xantiaman583





Drop me a PM or leave a message on here if interested.

[Xantiaman]

Hi Xantiaman

Interestingly, the xm's engine is rated at 150bhp according to some specs i have yet the activa got 145bhp and i know that at least the intake and boost piping was different but it seems strange how 5bhp vanished whilst slotting the same engine into the activa
Hope you find a good home for it anyway sounds like a sweetie.

D

There was a lower compression version of the engine which was used in some XM's and 605's, this is the one which had the lower output and often incorrectly the information was used for the Xantia which does have the higher compression version. 1/2 a psi of boost would be enough to correct the difference

[Dean]

so you saying its the other way around, interesting, i take it the compression was altered with different pistons so i will have to make sure i get the right ones on my rebuild, thanks......and sorry for hijacking your thread

D

[Xantiaman]

so you saying its the other way around, interesting, i take it the compression was altered with different pistons so i will have to make sure i get the right ones on my rebuild, thanks......and sorry for hijacking your thread

D

Yes pretty much, from what i have read. Don't take it as gospel though!

Citroen XM:

RGX - 7.9:1 (150 bhp)
RGY - 8.5:1 (145 bhp)

Citroen Xantia Activa:

RGX - 8:1 (150 bhp)

Peugeot 605:

RGY - 8.5:1 (139 bhp)
RGX - 8:1 (150 bhp)

Peugeot 406:

RGX - 8:1 (150 bhp)

Some errors in that but safe to say if you have an RGX, it will have lower compression but higher power, as some changes were made, this could be anything from a different cam to a smaller or bigger throttle body for example.

I think it would make very little difference which pistons you use if you intend to keep an engine standard boost, and even then one lot wont be stronger than another as its not really the compression ratio that causes detonation, its the high inlet temperatures and standard ignition set up. Both pistons will be cast not forged but will last well if looked after.

[Dean]

if you intend to keep an engine standard boost

Oh no no no no no, the boost is going up, not much though because i dont want to start messing around with fueling and then getting detonation problems etc etc ££££££ etc etc i want to keep it as refined as possible.
Surely increased compression/boost and charge temperatures go hand in hand to some extent??

Edit, just seen youve added the specs and mine is the RGX yes
D

[Xantiaman]

if you intend to keep an engine standard boost

Oh no no no no no, the boost is going up, not much though because i dont want to start messing around with fueling and then getting detonation problems etc etc ££££££ etc etc i want to keep it as refined as possible.
Surely increased compression/boost and charge temperatures go hand in hand to some extent??

D

The theory used to be the lower the compression the better for turbocharged cars, as this meant you could run more boost and not have so many issues with detonation. Back then , ignition/fuelling was not as sophisticated, and the best fuel was 4-star 98 octane (which did drop to 97 when they lowered the lead amount). Many modern turbocharged cars run more boost than the XU10J2TE and higher compression. Higher compression improves drivability off boost and means you need less boost to make power, you need decent management for this though! 10-1 is not unheard of.

Higher compression would not increase the inlet/charge temperatures, the charge temperature is affected by the compressor map and how much boost you run, and the intercooler. Its a complicated area which i dont know much about, but run a turbo outside of its efficiency and it quickly overheats the inlet side, not only that the exhaust gas temperature goes through the roof because it then becomes restrictive and this increases the risk of detonation even more

The standard ECU is ok handling more boost on the standard compression, and is mapped to 1 bar to give more fuel and retard the timing enough to prevent detonation. Go over this and you need aftermarket management to control things correctly. The cheat would be lower compression or higher octane fuel, you can see its easier to run higher octane fuel with the boost up as not only do you make more power, you decrease the risk of detonation.

FWIW, i have found the sweet spot on the standard turbo to be around 11-12psi. It makes no more power over this boost as its getting too hot. Next step without changing the turbo is a better intercooler and possibly water injection but thats a grey area.

[Dean]

mmmm ok, to me the intercooler seemed too big for a low pressure turbo

, possibly causing too much restriction but all this tuning stuff is new to me, ive always kept things standard but this should be more fun.
In your experience is it 1bar max the ecu can take or is it capable of taking small spikes of boost at above 1bar?

D

[Xantiaman]

mmmm ok, to me the intercooler seemed too big for a low pressure turbo

, possibly causing too much restriction but all this tuning stuff is new to me, ive always kept things standard but this should be more fun.
In your experience is it 1bar max the ecu can take or is it capable of taking small spikes of boost at above 1bar?

D

The intercooler is ok if you can get air to it! On an Air-Con car its really shrouded, on my Activa i am pretty certain the air con rad sits in front of it, then the intercooler and the radiator on the engine side.

The ECU on mine does not like spikes. My boost gauge takes pressure from just before the ECU so will see the same boost, and it will throw a code around 13.5psi, sometimes a little higher, sometimes a bit lower. I use an electronic boost controller to get it as accurate as possible as once a code is thrown, the ECU goes to default and you lose all your driveability settings when it was in adaptive mode.

[citroenxm]

Just to save guessing, ALL RAD Air Con and Interccolers are laid out as you said.. XM and Xantias..

Air Con RAD right against the Fans, or in front, then intercooler, then Rad.. Obviously, the Air Con rad when Air con in use needs the most cooling before the other two...


Paul

[Xantiaman]

. Obviously, the Air Con rad when Air con in use needs the most cooling before the other two...


Paul

....if you want to keep cool that is! But shocking effect in traffic, hot weather etc. Heat soak goes through the roof and performance drops until driven for a few minutes. Wonder if this is helping the sale?