zx td camshaft

8304 · Post by **8304** » 13 Jun 2006, 20:32

i know i will get the response of:

"if you want a fast car why dont you buy a fast car in the first place"

but -

has anybody heard of a performance camshaft for the zx turbo diesel. Its the same engine as in the pug 306 and they seem to do a lot of tuning bits so i was wondering if there is a camshaft upgrade available?

ive turned the boost and fueling up and it goes really well but have kinda run out of things i can do with the standard engine parts.....

cheers

alastair

mpr1956 · Post by **mpr1956** » 13 Jun 2006, 21:53

Hi there, I have heard it mentioned on here that a N/A 1.9 diesel camshaft improves the "breathing" of the TD engine, -perhaps some reader can either confirm or debunk this rumour... Something that will give a dramatic power increase is a larger, more efficient intercooler (I believe Allard supply such a beast). But of course then perhaps the poor old TD engine may have to work harder than perhaps it should ! I for one should like to hear how you get on.. ( I've tried a few times to improve the power characteristics of my 1.9 tdsx Xant.. with varying results ! )

8304 · Post by **8304** » 14 Jun 2006, 09:24

hi, thanks for your response....

what things have you done to your xant?

on my zx ive uped the boost from 14 psi to 20psi which means as you are putting more air in you can put more fuel in too.

theres 3 main ways of doing this:

1. adjusting the maximum fuel screw - (winding IN puts more fuel in bizzarley)

2. winding the hex bolt on top of the boost compensator valve (the alloy dome thing on the top of the bosh pump) down a couple of turns.

3. removing the top of the (alloy dome) compensator valve, removing the diagphram beneath and winding the spring base for the diagphragm (Spell?) down to permit higher fuel delivery at lower boost pressures.

All of the above can be done up until the point where smoke starts to appear (unburnt diesel) - i get a little bit of smoke below 2000rpm but the boost comes on at about 2200 (much lower revs than it used to be) which clears the smoke straight way as there is enough air to burn the increased amount of fuel.

I geet great satisfaction in burning boy racers in mk3 golfs and the like off at the lights in my L reg diesel!!!!! - they dont see it coming...

on the subject of making the engine work harder, mine has been tuned for about a year now and acts totally normal. The only comment i would make is its important to have good cooling system - mine has a new radiator and is flushed etc with good anti freeze for corroision inhibition - and i keep a very close eye on it - i thnk the risk of overheating is a bigger threat to the engine than te increased output...

its all good fun!!

alastair

8304 · Post by **8304** » 14 Jun 2006, 09:29

one other thing....

i have been thinkinrg about bigger intercooling as the charge temperature of the air rises significantly as its at 20psi rather than 14 psi (air warms up when it is compressed)
i got a bigger intercooler off somthing like a shogun from my local breakers to be mounted at the front of my zx behind the bumper.

what do you think the gains from fitting a xantia front mounted intecooler would be?

(my zx has the engine top mounted one - which probably acts more as an interheater rather than an intercooler!!!!)

cheers

alastair

sooty · Post by **sooty** » 17 Jun 2006, 21:00

I've read in the former Andyspares forum, that someone said there is no difference between the td and na camshafts as they have the same part No.

Best do a search.

In anycase you'll find that as with most performance camshafts you will gain the power at a higher rpm, so by the time you get there the governor has stopped you going anyfurther. So whats the point?

The best power increase would be to fit a good intercooler and a better turbo.

Dave Burns · Post by **Dave Burns** » 18 Jun 2006, 09:57

I have shafts from both turbo and n/a engines knocking about, the position, shape and size of the cam lobes look identicle, never taken any measurements though.

Dave

8304 · Post by **8304** » 18 Jun 2006, 11:22

yes valid points - i think extra intercooling is the way forward...

jeremy · Post by **jeremy** » 18 Jun 2006, 11:52

If you instal a large intercooler at the front of the car you may get a lag problem. Lag is one of the reasons why manufacturers don't use very high boost presures (takes a long time for the turbo to produce full pressure - problems of accelerating a loaded turbo etc)

The top mounted intercooler does have the virtue of being compact - move the intercooler to the front and you have a considerable length (8 to 10 feet?) of large diameter pipe which has to be filled with high pressure air before it gets to the engine - and inevietably this takes time!

All the evidence points to there being good gains from the use of a good intercooler. Obviously its construction quality is important - ie does it flow well?

Have you tried cooling your existing top mounted one by spraying it with cold water? System is a cold tank a washer pump and some good mist jets - to spray the water when max power is needed. I think this may have been discussed on here before but that was several years ago.

Post by **Peter.N.** » 20 Jun 2006, 12:15

As far as I know all XUD camshafts are the same, they are designed for optimum performance/fuel consumption to match the characteristics of the engine. Theres not much point in trying to increase the power at high revs as the engine runs much less eficiently there and you will just burn a lot more fuel to generate a lot of heat!

Before you try to increase the power any more I would suggest you stock up on head gaskets.

Your best bet is to fit a 2.1 td engine, they are not only more powerful but more efficient.

8304 · Post by **8304** » 21 Jun 2006, 13:08

does the 2.1 td have the same block as the 1.9 td?. i ask becuase if it does i might just do that becuase it should go straight in.
how much more powerfull is the 2.1 over he 1.9?

with refference to performance cams, i might be wrong but everybody is talking about power gains at big revs - is this not just because performance cams are usually associated with petrol engines and not low reving diesels? surely a cam could be designed to let the valves stay open for longer at low revs to allow a longer space of time for charge to enter the cylinder. In doing this you have to get more power - at whatever revs??

jeremy · Post by **jeremy** » 21 Jun 2006, 14:14

The 2.1 TD is about 110 BHP and 184 lb ft torque at 2000 RPM.

What is interesting is that in terms of the XUD engine is that 1905 is the largest 2 valve indirect injection engine in the series - as the 2.1 has 3 valves.

As peugeot were axxious to get as much power as possible out of these engines it suggests to me that problems were encountered with breathing on a 2.1 and to get the required increase 3 valves had to be used. this may also have something to do with emmissions - but I can't believe that the 2.1 has 3 valves just for fun.

I think the 2.1 uses a different and stronger gearbox.

Stewart(oily) · Post by **Stewart(oily)** » 21 Jun 2006, 19:19

I read on one forum that the N/A camshaft on BX is different and comes close to the Piper cams offering for the TD lumps, being as they are readily available it looks like a good starting place, I have increased my boost and fuelling in my BX and am very pleased with the results even though I am only running a modest 15 psi, beyond 18 psi the law of diminishing returns applies and a larger more efficient intercooler is needed, Vanny rigged a homemade intercooler wetting setup and was pleased with the results, has anyonme fitted top gear from the BE3 gearbox as fitted to HDI engined cars to further raise the ratios?
Stewart

Post by **Peter.N.** » 21 Jun 2006, 23:32

The 2.1 uses a similar block to the 1.9 and even the same oil filter and similar engine mountings. The main difference I have come across is that the thermostat is located at the bottom rear of the engine and is in the return rather than flow pipe. I think this has been done to improve the cooling efficiency of the head and to prevent airlocks, the main cause of head failure and it seems to work as I have not experienced or heard of a cracked head on one. My previous XM boiled due to a cooling fan failure and suffered no ill effects, you dont usually get a second chance with a 1.9!

The idea of tuning a petrol engine is to get more air in to increase the power output at high revs, diesels by their very nature are not capable of producing more power efficiently at high revs, look at the torque curve! What jeremy says is quite right, in order to get enough air in to produce 110 bhp efficiently which means cleanly, they have been compelled to use 3 valves per cylinder.

The 2.1 td is a brilliant although somewhat complicated engine and not only produces more power more quietly than the 1.9 but will also probably use less fuel doing it. They are also very durable, My last XM had covered 292k miles when I sold it and was still going strong.

Kowalski · Post by **Kowalski** » 22 Jun 2006, 10:17

Peter.N. wrote: The 2.1 td is a brilliant although somewhat complicated engine and not only produces more power more quietly than the 1.9 but will also probably use less fuel doing it. They are also very durable, My last XM had covered 292k miles when I sold it and was still going strong.

The figures I've got for the 1.9TD and 2.1TD in the Xantia say that the larger engine is more thirsty, urban, extra urban or combined.
If you compare the non-cat mechanical pumped 1.9 to the 2.1 in the Xantia (with Cat), there is a difference of 3 mpg on paper but there is very little in it (less than 1 mpg), if you compare the later cat and egr equipped 1.9 to the 2.1. I'm sure it all depends on how you drive and it may be possible to get better economy out of a 2.1 but you have to remember that if you have a heavy foot a bigger engine has a bigger capacity to drink fuel! Fuel economy and weight aside, as you have said the 2.1 is better in a few ways than the 1.9, I think it comes with a nicer gearbox too.

Post by **Peter.N.** » 22 Jun 2006, 11:28

Kowalski

I am only going by my personal experience, my XM estate is capable of 55 mpg and averages 40 + mpg locally which is as good or better than my wifes ZX. We came back from a 2000 + mile trip around the Scottish highlands last weekend and averaged slightly over 50 mpg with 4 adults 2 dogs and our luggage on board! But... I dont drive very fast, mostly at the statutary limit and dont push the car hard, I also live in a rural area so I realise that these are factors.

As the efficiency of a diesel engine decreases significantly with increased throttle opening the use of a larger engine, with the same number of cylinders, will result in an improvment in fuel consumption, so the way that I drive, the 2.1 gives a better return than the 1.9, I know, I have driven both, but I appreciate that wont allways be the case as if you make use of the extra power you will use more fuel.