Supercharged Dervs - Educate Me!

[Steve]

Evening fellow RR'ers!

As some of you may be aware, i have a new "daily" if you can call it that in the form of a Land-Rover 110 in an Ex-Military flavour its old and its dog slow so will be upgrading the motor for a 200TDi at some point soon but I'm interested in perhaps ditching the turdblower for a supercharger.....cos i like to be different ;D

Whats the crack then? Hard to do or just not effective? I aint done anything in the way of research just yet as the idea just came to me and would like your opinion on the matter

Discuss.........

Steve

[mk2cossie]

hmm, no reason why not ;D

could even mount a suitable charger where the aircon pump used to live i should think

would need the non existent turbo mounting cobbling up to a normal downpipe and the right pipework from the supercharger via intercooler in to the inlet

[scruff]

Twincharge.......

[HARDCORE]

Compound!

[retrowagen1234]

Put a tiny little pully on it so its allways on boost. Otherwise youll have to rag the off it to get any boost. Which seeing as diesels don't realy rev would be a little annoying...

[ruishy1]

def compound charge it, you would see massive power gains and zero lag, plus if you size the turbo correctly there will be no drop off in power till you hit 6.5k !

[Tom Majeure]

+1 for compound charging. Superchargers are great and all but think of all that lovely "free" energy wasted down the exhaust if you don't put a turbo there to nom it all and excrete it back into your intake

[claymore]

Well I would have to agree with the two posts above, although mine is a petrol.

[sparkyt]

I did a derv caddy van some time ago. Used a MERC m45 charger it ran well with good boost but if I was to do it again I go for a much bigger charger . The sound was great from the charger always put a smile on my face .. do it mate but go big use an m72

[claymore]

an M45 will be fine if you compound charge it, that's what I use.

[Steve]

Gentlemen thank you for your input

Compound-charging does sound like an interesting direction, one i shall look further into

The 200TDi motor is 2.5ltr so would the M45 be upto the job with a standard 200 turbo? Or do i have to go along with the usual term........bigger is better? ;D

I'm guessing the 'charger would be mounted first in line before the turbo? If so then a standard inlet manifold can be cut up so the 'charger can bolt straight to it and then just a case of making a bottom pulley to suit?

Will need to look into modding the injector pump for a dash more fuel as well but can see that being too much of a problem

Anyone know if there is a bigger pump head than the one fitted to the standard Bosch pump on these motors?

Sorry for all the q's chaps but I'm normally more at home with a petrol motor than these dirty dervs

Steve

[claymore]

Big turbo blowing into the supercharger, an M45 would be just fine. I know my car is a petrol, but have a look at my thread.

retrorides.proboards.com/index.cgi?board=readersrides&action=display&thread=71239

[ruishy1]

when compound chanrging you can use a much smaller charger. an eaton spits out a certain amout of air dependant on the air pressure going into the intake, and the speed the charger is spun at. so most need to be spun at high rpm due to atmosperic pressure. but when you have a turbo blowing into the intake, it multiplies the pressure by x amount, dependant on which eaton you use and the ratio its being spun at.
ive got the calculations to work out boost, so if you let me know which pressure the turbo runs at, and which eaton your going to use and the size of the crank pulley i can tell you how much boost its going to be pumping out

[rtlkyuubi]

Aug 26, 2011 6:39:10 GMT ruishy1 said:

when compound chanrging you can use a much smaller charger. an eaton spits out a certain amout of air dependant on the air pressure going into the intake, and the speed the charger is spun at. so most need to be spun at high rpm due to atmosperic pressure. but when you have a turbo blowing into the intake, it multiplies the pressure by x amount, dependant on which eaton you use and the ratio its being spun at.
ive got the calculations to work out boost, so if you let me know which pressure the turbo runs at, and which eaton your going to use and the size of the crank pulley I can tell you how much boost its going to be pumping out

no need for calculations as what ever it is, it needs to be lots ;D


That should do the trick

Also since its derv and a 'truck' it needs these:

;D

[chairchild]

When it comes to 'chargers on dervs, the bigger the better. An M90 would be more suited - you don't want to over-stress the charger, as it'll just dump it a buttload of unwanted heat


If compound-charging with a supercharger, the standard turbo will be far too small. You'd ideally setup the supercharger to give mild boost at idle (2-5psi) so as soon as you add more fuel, it'll move like a scalded cat, AND give enough exhaust gasses to run a pretty large turbo.

I'm currently trying to make a control system for a VNT turbo, to run on my 2L derv - far more efficient than running two seperate things to give boost




Also, what pump does yours have? If it's an old mechanical bosch pump, give me a PM, I can tell you almost every trick in the book

[ruishy1]

the only problem with trying to obstain an m90 is the availability, not many cars over here used them apart from a few astons and the 4.0 straight six xjr.


If he is just running a supercharger then yes bigger is better, but bigger is not always better, you need to work out the boost you need to try and get into the efficiency island of the charger otherwise your going to be losing power.

With compound charging you can fit a tiny charger if you like, as long as you don't spin it beyond what its deemed fit for.

[TurboDieselWeasel]

As far as I know, common practice isto bypass each charger, so none of them act as a restriction to each other, if flow of one exceeds the capabilities of the other.

[Colonelk]

Compound charging terminology always confuses me, thought compound was when you use each blower as a pressure multiplier thus ending up with silly boost levels like on the tractor pullers?

[ruishy1]

thats exactly what we are suggesting. keep the turbo, but have it feeding the supercharger thus ending up with huge boost

[Robinxr4i]

From what I've seen/read there are plenty of marine/generator supercharged diesels I guess this suits the low reving/high torque nature of the engine, although most (if not all?) are 2 stroke. IIRC you can't have a 2 stroke N/A diesel it doesn't work because they have to run a wet sump, so the cycle of the piston doesn't force air into the combustion chamber like it would on a petrol. Make sence? (although correct me if I've wrong!)

Sept 3, 2011 11:04:38 GMT Colonelk said:

Compound charging terminology always confuses me, thought compound was when you use each blower as a pressure multiplier thus ending up with silly boost levels like on the tractor pullers?

That's what I thought? I "think" (might be wrong) the VW 1.4 twin charge engines although the turbo and supercharger blow through each other don't boost at the same time. The super charger must have a controller to switch it off when the turbo come in otherwise as Colon said you'd end up with some kind of monster boost Golf ;D

Here we go.... found this on the vag engine.....

The compressor and the turbocharger are connected in series. A control valve ensures that the fresh air required for a given operating state can get through either to the exhaust turbocharger or the compressor.

The control valve is open when the exhaust turbocharger is operating alone. In this case, the air follows the normal path as in conventional turbo engines, via the front charge-air cooler and the throttle valve into the induction manifold.

The compressor is operated by a magnetic clutch integrated in a module inside the water pump. Under turbocharging conditions, the clutch disengages the compressor.

So it's twin charged, NOT compound.

However a road going compound diesel sounds epic!