Noisy Turbo!?

Thats interesting - definitely different to the 330d posted in that respect. I never bothered revving my old Mk1 mondeo TD that high, but mostly because it wasnt really going anywhere regardless of revs!

Out of curiosity, why does the power tail off in the newer ("better") common rail cars?
 
miniyazz said:
Doesn't mean you won't do more damage at 4,000 rpm than 2,000 rpm. Just means that they've decided 4,500 rpm (or whatever the limiter might be) is the point at which excessively more damage is done to the turbo for comparably little gain in power.
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The limiter isn't there to protect the turbo, Jeez where are you getting this stuff from? :( *shakes head and crys*

A Limiter is in place as thats what the manufacturer has deemed a sensible limit to maximise engine life and stop the thing from shaking itself into a thousand pieces :p

The turbos on these engines are hairdryer size, the only time you're going to damage one is if you've given the car a thrashing of its lifetime and imediately switched the engine off.

I remember taking my 205 TD engine to the limiter once in 3rd gear, the Turbo didn't sound like it was trying to escape at any time, I don't recall it sounding any noisier than usual either... also, the so called 'limiter' on these engines is nothing more than a stop on the diesel pump, you don't bounce off the limiter like in a petrol you just hit a brick wall of power.
 
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TaKeN said:
The limiter isn't there to protect the turbo, Jeez where are you getting this stuff from? :( *shakes head and crys*
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I have no idea what a turbo is or how it works. I was taking the comment I quoted and assuming it had some background in fact, and basing my reply on it.
:p

So if my post was totally out of the ball park, sorry, but I still think it answers ethos :)
 
No worries ;) - Here is a Wiki Page to have a read

What etho is trying to explain.. is that the manufacturer wouldn't allow the turbo to spin so quickly (in relation to the engine revs) if they thought it would cause damage.

I'm also getting rather confused as to why people think that a turbo on a diesel engine is more likely to recieve a harder life than on a petrol engine :p

The thing has a direct oil feed to it, if you switch the engine off too early after a hoon the oil will sit there in the bearings getting boiled which causes the damage..

iaind said:
Thats interesting - definitely different to the 330d posted in that respect. I never bothered revving my old Mk1 mondeo TD that high, but mostly because it wasnt really going anywhere regardless of revs!

Out of curiosity, why does the power tail off in the newer ("better") common rail cars?
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I seem to remember the 'revving a diesel' debate we had on here a few months back, and I recall the general consesus was that it feels slow because the high torque levels have dropped off at this point.

EDIT - Power graph of my common rail. Not standard though, I'll try and find a normal '90 bhp' engine :)

resizedf.jpg
 
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TaKeN said:
I seem to remember the 'revving a diesel' debate we had on here a few months back, and I recall the general consesus was that it feels slow because the high torque levels have dropped off at this point.
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Sounds about right - If I push mine to the higher end of the range, when I change up I actually get more of a shove than I was getting in the lower gear
 
miniyazz said:
A good read, thanks. Are remote turbos used much then? (Apparently reducing/eliminating heat problems through being further away) As no examples were given of any engine using one.
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Not sure tbh, Most turbo systems run intercoolers to cool down the boosted air after its gone through the turbo, these give cooler intake temperatures.
 
iaind said:
I'd be interested to know if many people do this, and if so how they work it into their driving routine.

I always let mine warm up before I use full boost (my journey to work out of town through traffic before joining the m5 makes this easy), but when I arrive at work or back home I stop the car and get out.

Do people actually sit there with the engine idling doing nothing when they arrive places?
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If you drive sedatley off boost for your last few minutes theres no need for the idling :)
 
TaKeN said:
Not sure tbh, Most turbo systems run intercoolers to cool down the boosted air after its gone through the turbo, these give cooler intake temperatures.
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Trubo's get hot anyway as they are driven off exhaust gas, remote turbos give tremendous lag not to mention the miles of pipework you need, plus oil and water lines having to run to them
 
twoblacklines said:
If you drive sedatley off boost for your last few minutes theres no need for the idling :)
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Ah, thats alright then - normally i'm coming back through traffic so dont need the boost anyway. I dont exactly drive it hard normally so I'm sure it will be fine.

I'm just conscious that its boosting from very low down, not far above idle speed
 
Some of these dyno graphs just do not make any sense whatsoever, the drag losses are way too high. Any car that has 30%ish rolling drag in neutral/clutch down must be a complete PoS and I doubt very much that is the case.

4wd cars may push as high as 20% loss, but a 2wd shouldnt be worse than around 17-18%, fwd closer 13-14%.

It looks to me like the rollers themselves have a lot of drag, giving an inaccurate WHP figure.
 
TaKeN said:
Try both, although I think all we're going to get is the tractor noise :(

I tried recording a problem with my HDi a while back and it didn't pick up the right noises!
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Well, the vid is finally uploaded, unfortunately something in my camera mount arm was rattling around, which totally screwed up the sound! :(

Here's the vid anyway:

It does just sound like a tractor, or cam mount rattling sound, so I couldn't hear any turbo whine at all on the vid, even tho I could hear it plain as day in the car at the time.

I may try and get another recording when I can, next time I'll have the camera in the car instead of on the front bumper, at least the picture came out ok even if the sound is really really poor! :o
 
The turbo is next to the bulkhead, so any noise can enter the passenger cabin more easily than it can get to a cam on the front bumper.

Might want to try a remote mic inside the bay?
 
I had the same problem when trying to pickup the rather epic turbo whine from a Tractor exhaust I'd errr-hermm 'Modified'

It didn't pickup what the human ear was hearing at all... :(
 
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