HDi Remap - Anyone had one for a few years?

[Welly]

I've been thinking about this remapping here............

The 'new' HDi's are:

• 1600cc = 110BHP
  2000cc = 136BHP
  2200cc = 170BHP (twin turbo)

Now, these units must run a high boost to begin (with looking at the standard BHP's) so how can they take even more boostage on what is (presumably) the same mechanicals as the older HDi's?

I can see that the standard 136BHP would run a higher boost that the old 110 and the fueling would have been mapped to suit but, unless the HP fuel pump/intercooler/turbo is different now, I would have thought the engine is already near it's optimum, and safe, BHP?

[jameslxdt]

all these units Welly suprisingly, run very low boost, apart from the 1.6 110 which has the overboost feature, so 90% of the time its a regular 90 1.6, but when you give it some it overboosts, for no more than 40 seconds but you have 110 bhp
the new twin turbo unit also runs a very low boost as well, the key to this set up is the fact the turbos are sequential, so there is no lag and it maintains the same boost regardless of revs
the key to any diesel engine is the fueling, as this decides the entire outcome of what the engine does, if you introduce more air into a petrol engine, i.e. open the throttle the engine's power increases so it revs, so high boost equals higher power, but on a diesel engine, the fueling is what controls the engine speed and power, if you wound the wastegate up on your 110 it will do nothing (except obviously flag the K light) as it needs the fuel to add the power, peugeot really do know a thing or two about common rail diesels, heck they know a shite load more than VAG, the reason pug common rails dont jug out half the power of a VAG PD engine is because peugeot put emissions and fuel economy much further ahead than power, the intial idea of the HDi was an ultra clean engine not a very powerful one

the new units are completley different to the older HDi's essentially the internals are the same, but its the exhaust systems, turbo's and management that seperate them from the old units,
so essentially, the boost is no different, lower if anything, its just the fueling they have refined

[Welly]

Good answer there fella.

So, with 'Blue407's' remap here he would have had a slight boost increase and a new fuel map?

I suppose it is a battle between fuel economy and performance with new Diesels. I understood that the VAG 1.9 150BHP PD engine is not really that economical

I honestly think that Diesels have become sooo complicated that they will no longer give the uber high mileages of years ago. Sure they are economical AND powerful but I can't see them being as long lived as, say, an old 405 dt with it's more simple set up. Still, maybe people are not really interested past the 100,000 mile mark anymore - they simply buy a new car!

[jameslxdt]

modern diesel's are getting too powerful, in theory they should still last as long as an old diesel engine as the diesel fuel does a LOT of lubricating but the engines are just too stressed, VAG PD engines may as well be petrol as they are hardly economical at all, they are outstanding engines, but VAG have kinda lost the plot of why most people buy a diesel, Blue407's remap would have had no change to the boost map, just a change to the fuel map and smoke map, but which in turn will be chugging out more exhaust gases and pushing the turbo harder and creating more boost, there is also the problem of getting round the smoke map as well, as the fuel map is chucking in the fuel for optimum power, but the fuel map says no, lean off as it will smoke, it switches like an oxygen sensor (lambda probe whatever you call it)but mucho faster and with no sensor, as the smoke limit is mapped, so if a poor remap was done to the fuel map, but not the smoke map it will have no effect as it will lean off to stop the smoke

[dervpower]

i wonder if thats the case with mine as when i had the remap i noticed only a small difference whereas some guys on here rave about theirs?

[Welly]

So why are these plug-in's so crap then? they do (in theory) the same job of increased fuelling albeit in a rather Heath Robinson way. But these plug-ins just tend to produce excess smoke don't they?

[Malachy]

I agree with you point about Dyno's every one is different, they can only give an indication and figure should just be taken with a pinch of salt.

yes this is true but even comparison figures can be bs as its so easy to rig them, add in extra factors on the dyno computer to add more power or drag the brake on rundown etc etc etc its not unknown for tuning companies to do this to achieve there "awesome remap" results.

[jameslxdt]

So why are these plug-in's so crap then? they do (in theory) the same job of increased fuelling albeit in a rather Heath Robinson way. But these plug-ins just tend to produce excess smoke don't they?

because all they do is confuse the engine ecu and the rail pressure sensor into raising the fuel pressure stupidly high, in turn just chucking a shite load of fuel in, which will gain you a small amount of power, but puts a huge strain on the injectors and high pressure (if they wasnt stressed enough) but also most of the fuel is wasted and unburnt, hence the smoke, but as the engine ecu is being confused the smoke map doesnt back off the fuel and allows the smoke

[Blue407]

all these units Welly suprisingly, run very low boost, apart from the 1.6 110 which has the overboost feature, so 90% of the time its a regular 90 1.6, but when you give it some it overboosts, for no more than 40 seconds but you have 110 bhp

I believe the 2.0 136bhp that I have also has overboost, probably another reason the Dyno runs are lower than expected.

[Blue406]

Hoi!

You nicked my name.... almost... kinda....

This is gonna confuse folks here! LOL

[Frenzy406]

Hi there,
To add to a few comments ...
I had the 180 map installed on my 406 2.2 136, about 35,000 miles ago, and initially felt a lot more power!
Great for a couple of weeks of "driving it like i stole it" ... then i started getting a Bit bored :p
So, I fitted the huge front mount Intercooler, a boost bleed valve, and a boost gauge to have a play with boost levels ;)

Now I think the 136 boost was about 1.0 bar, the 180 map produced a reading of 1.3 bar, so I itched the boost upto 1.5 bar.
Great ! Faster, more acceleration. So I obviously had to keep increasing the boost. ( I'm a scientific, arty, kind of engineer)
When I reached about 1.8 bar the ecu would occasionally go into limp mode, and I'd have to disconnect the battery for 10 seconds and continue (I've thought of fitting a battery kill switch in the dashboard someday to save stopping the car and losing valuable seconds ;) )
Pushing 1.8 bar felt like driving a rocket (well, to a 406 driver) for about a month, til the turbo threw a couple of blades...
So I fitted my spare turbo and dropped boost to 1.5 bar for safety.

The clutch did start slipping one day last year in 5th, and I started looking into paddle clutches and the like, yes they do exist for this engine ! ... But then after about a week it stopped slipping... No idea why but ok
The original gearbox started being crunchy in 4th after ragging it back from PVS, probably due to me ramming in impatient gear changes ? And after a while started losing 1st,reverse, 2nd all within a week. So I fitted spare gearbox. Few months later 5th started clonking on the way back from FCS, so I popped the end cover off and swapped 5th from the original box, which lasted about 3 months. So I just removed the gear and continued with 4 gears.
About a month later, a year after fitting the spare turbo, and enjoying whatever Bhp that' was giving me, occasionally tweaking it a bit higher, the spare turbo threw some blades. It's now waiting for me to make a free flow manifold to fit a bigger turbo and play some more
Dunno what else will break after I do that but Hey, as somebody once said, lifes a learning curve (or was it a circus ) ;)

Couple of notes...
In 35,000 miles I've had no major engine component failure such as piston, crank, rod, bearings, head gasket ...
The worst Fuel consumption has always been 29-30 mpg no matter how stupid I drive or how I increase the power.
I have a straight through exhaust system, no Cat, FAP nor silencers.
Fitting huge Intercooler had no detrimental effect on spool up, lag, etc... But after a hard run, the inlet tank is Hot and the exit tank is Icy ! So it is definitely cooling the charge and making it more dense allowing higher boost, and possibility of a larger turbo.
I do get a very sooty rear end, even when I'm increasing boost ( and not fuel) :p ( Altho thrs no FAP to catch all the soot and throw it out on regeneration )
Increasing boost alone does increase power and torque. (I've done this on 3 of other peoples' 406 Hdi's.)
My girlfriends 2.0 Hdi had a "fuel rail pressure sensor signal fooling box" fitted before she bought the car - this seems to make the 110 feel somewhere in between a 110 and a 136. So increasing the fuel does give more power, don't know if I'd bother spending big £££ on 1 tho ... Oh and her 110 had the DMF falling apart so I fitted the 3 piece conversion. - been running 10 months with no probs ( although it had a little vibration at the bite point for the first couple of weeks) .

Hope someone can learn from my curve in the circus of remapped life ...