When does the turbocharger kick in?

[xraybob]

On my MY04, when does the turbo kick in and under what conditions? If it is driven from a start with a light right foot and under the thought of getting the best economy, does the turbo engage or does it only under hard aggressive driving? Otherwise does it function like a non-turbo engine?
Thanks.

[John@CdnRockies]

The turbo generally engages under hard driving - pedal to the metal and when towing up hills. As it is a low pressure turbo I find it difficult to spot the transition to turbo boost. I wish there was a better way to determine those situations in order to spare its use. On the other hand, my dealer has said that the turbo is near bullet-proof - they have had only one instance in the past 20 years of a unit being defective.

Under sustained use (a very long tow up some of our Rocky Mountains) I can smell what seems to be oil burning. I figure that has to be turbo heat generation which disappears as soon as the summit is reached. I have never experienced that in just driving the car by itself (even aggressively) up those same hills.

John

[Forkster]

There are also a couple of mods that XC70 owners do to help improve turbo performance. The infamous 'wastegate mod' - where you turn the wastegate adjustment one turn - helps the turbo kick in sooner.

The second is repair oriented - IPDUSA sells a HD Turbo Control Valve (http://www.ipdusa.com/product.asp?strPageHistory=category&numSearchStartRecord=0&strParents=127,381&P_ID=4234&CAT_ID=814) - a lot of the OEM fails plus when you throw in cracked hoses it makes the turbo ineffective and unresponsive. It's designed to last a lot longer than the 6-7 years most TCV's fail - and you can also add on the boost gauge. Either way, when your TCV is faulty or if your hoses are cracked, it pretty much kills your turbo.

[JRL]

Nothing infamous about it, it works and the boost DOES come on earlier and more rapidly.
In normal conditions (in an XC LPT engine) the boost starts to move at about 1800 but you start to feel the boost at about 2800 RPM with full boost (pedal to the metal) at about 3200 RPM

[VICIII]

does this mod hurt the car in anyway?

[JRL]

[sly]
does this mod hurt the car in anyway?

Not in the slightest unless you turn it way too far, in that case it will throw a CEL. You're not "hurting" anything, it just won't run optimally.

Normally without a gauge to double check, one to one and a half turns is totally safe.
Some people have gone two turns on their R's and liked it but that's a different engine.

The early 4.4 motronic wastegate (98 and earlier) can be shortened up to 4 turns! [sly] However, if the car has a chip, (ECU mod) the boost comes on so fast and hard it can become almost dangerous to drive :eek:

I think that's totally unnecessary on an LPT engine unless for some reason it was set way too far open from the get go.
I always start with 1 turn, you can always go another 1/2 turn more..
If you want to try it, here:
http://forums.swedespeed.com/zerothread?id=103642

This is just one thread, if you go to Swedespeed and do a SS google search, (upper right of any page), you will find several threads, but this one is as good as any without getting into all the esoteric conversations about doing it in the first place.
You do not need a baseline boost reading for these engines, they're not highly tuned.
As I said, one to one an a half turns will be just fine, definitely makes them more responsive and "zippy" [cool2]off the line

[VICIII]

Will try it when I work on the car tomorrow..

Thanks.

I was worried it would help destroy the trans...:eek:

[Allen]

Will try it when I work on the car tomorrow..

Thanks.

I was worried it would help destroy the trans...:eek:


Trorque limiter.

[Giles]

[sly]

I think that's totally unnecessary on an LPT engine unless for some reason it was set way too far open from the get go.
I always start with 1 turn, you can always go another 1/2 turn more..
If you want to try it, here:
http://forums.swedespeed.com/zerothread?id=103642



The link is of a S40, but pardon my nack of knowledge, is the 2001 V-XC70 the same set-up? I have a right hand drive version and cannot find the actuator rod. Help please!
Regards,
Giles

[billr99]

The link is of a S40, but pardon my nack of knowledge, is the 2001 V-XC70 the same set-up? I have a right hand drive version and cannot find the actuator rod. Help please!
Regards,
Giles
Doesn't make any difference. Engine orientation and thus stock turbo layout all pretty much the same across models (assuming a 5 cyl, right) and LHD/RHD. The linkage you seek is hiding under the manifold heat shield. You can barely see it with the shield on.

Cheers,

Bill

[Giles]

Thanks Bill.

Is it easy to get the sheild off or out of the way?

Regards,

Giles

[JRL]

Not really.
Older cars the shields are rusted and the rearmost (firewall side) bolt is a toughie to get at

[Giles]

Are there just three bolts and do you need any special spanners or drives?

[JRL]

Nope, just small and nimble fingers

[Giles]

Small and nimble, counts me out, I'm off to the local turbo shop on Friday and they can do it. I don't mind keeping someone employed when the jobs beyond me. They're going to measure before and after mod boost while they're at it. They tell me that from what they have previoulsy done one turn = 1lb of boost but more turns become problems. The biggest gain is the turbo reacts quicker. The best way to increase boost is a Stage 1 ECU upgrade. I'll give this actuator rod mod a go first and see what happens.
Regards,

Giles

[JRL]

If you read all of the threads you do NOT GET MORE BOOST
What you do get is the maximum boost that your ECU will allow and to get it more quickly.

[Giles]

I respect your opinion and knowledge but please, no need to YELL.
I'm only going what experience the local mechanic has had what he relayed to me this morning. We will see on Friday whether there are any boost measurement differences.
Regards,
Giles

[JRL]

The only time you would actually get a bit more boost is when/if the wastegate was set (or had moved) to a more open (longer) adjustment, thus it never was getting proper boost.
Your ECU will hold back any more boost that you would try to "adjust" in.
If you go too far, the ECU will shut off the overboost

[Giles]

The only time you would actually get a bit more boost is when/if the wastegate was set (or had moved) to a more open (longer) adjustment, thus it never was getting proper boost.


Hi JRL,

This is what I have suspected, that the wastegate setting is not quite right. I've now had the car for four months and done some minor maintainence jobs but I've always thought that the turbo lag was too long and didn't have the influence I thought it would. Maybe I was hoping for too much from a low boost turbo but its got better over time and a one thing that did amaze me was when I changed a faulty thermostat it actually made the turbo react quicker. I think that somehow the ECU was getting some indifferent temperature readings and not allowing the turbo to function correctly. Call me crazy but it did make a difference.
Regards,
Giles

[Chilled Man]

Dont you have a turbo button ?

Its on the back of the steering wheel :D

Its kind of like Vtech :D

[Giles]

No turbo button, but the flux capacitor is almost complete.;)
No clutch required either.:D

Regards,

Giles

[Chilled Man]

Details man Details :D

[Giles]

Not before you show me your Turbo button.:eek:[happy]

The car is in getting the boost measured this morning and the actuator rod checked and tweaked.
It will be interesting to see where its base line is before ordering the IPD software kit.

Regards,
Giles

[Giles]

I've had the actuator rod adjustment done and it has made some noticable difference. The turbo spools up much quicker and it revs better, especially in third gear where previously it was quite lame. The kickdown is more responsive and no error codes have come up. The local guys did the adjustment a little differently than has been mentioned on previous posts. They positioned a 1mm spacer on the rod rather than try and get to the adjustment nut. Much quicker and easier they say.

Regards,

Giles