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Why wont CRD talk to your about it. I would insist they explain the tune and setup better - this will stop all the maybe this maybe that.

I know I have spent a huge amount with my tuner and I had a boost leak fixed yesterday - took them 20 mins to pull apart the intake replace a gasket weld up the intake pipe to stop flex and strengthen it but it back on and send me on my way for free.

All from a phone call that morning and they took a car of a hoist for me and got it sorted. Happy customer.

find a better garage as soon as possible what else could be wrong?

I am starting to agree with the plausibility of his theory - I wouldn't go so far as to say that's the issue, but.

You have a .82 open housing, a .84 open housing is a different beast and in most cases I would expect it to be more comparable in to a .6x open housing which would make people shit themselves if it was said that someone was going to put on a 3.2 litre aiming for 400kw+ on petrol.

When I first heard about this I thought the hotside was going to be too small and that was before I learnt it was a small divided hotside on it, I've never thought about or had to deal with a bad turbo match like this causing excess back pressure - I like to think all the things I have been involved with have quite well matched turbos and as such exhaust manifold pressure has tended to be sane and never thought about the effect on the waste gate but the more I think about it the more it makes sense. Always nice to learn something :)

Can you imagine what it is like for me, a bloke that knows nothing about modifying if you blokes are divided

.

There seems to be many things it could turn out to be, or combinations :/

How is your boost controller set up peter?

It would need to be adding boost to the top port to overcome high back pressure.

haha, you jest mate, maybe Mick could tell you if he could tell from the short time he had here ?

Fairly narrow minded, all you can say is its the turbo. Its rated for over 700hp ffs, if there are no other restirictions it should acheive close to that.

Can u tell me why my engine with a .82 rear housing does not have this issue?

It says if. Also, everyone else is saying it is soley the tuner/tune. So how are they any different when it comes to being 'narrow minded'

Why wont CRD talk to your about it. I would insist they explain the tune and setup better - this will stop all the maybe this maybe that.

I know I have spent a huge amount with my tuner and I had a boost leak fixed yesterday - took them 20 mins to pull apart the intake replace a gasket weld up the intake pipe to stop flex and strengthen it but it back on and send me on my way for free.

All from a phone call that morning and they took a car of a hoist for me and got it sorted. Happy customer.

find a better garage as soon as possible what else could be wrong?

It is too late for talking or answers, its been over 9 months, maybe it is going exactly how they feel it should be running and that is fair enough as the car is still fun to drive. They fixed all of the problems I took it back for, so :)

I do not have to agree that it is all that it should be, even if I am wrong .

But it's time to move on and go somewhere closer to home and get a second opinion to what I consider to be a problem, it should have more at lower rpms.

The good thing about this was getting an opinion from a bloke that knows his way around an engine and has a fairly good idea how the throttle response should/could be.

  • Like 1

It sounds like you are relatively happy with the sheer power it has? Hopefully a bit of touch up tuning and maybe cam swinging might make the low down a bit better and bring it together to be what you want :)

There have obviously been a few clued up minds involved, no doubt not least CRD and there are question marks still raised so this kindof highlights how many variables there are to be addressed when getting something absolutely humming perfectly and a good percentage of cars are running safe and well with potential improvements to be had but we have to draw a line somewhere. I hope this works out to be what you were after, and even if there is "more" it doesn't mean its not right if you don't have it - so long as its not because something is actually blatently wrong.

  • Like 1

haha, you jest mate, maybe Mick could tell you if he could tell from the short time he had here ?

Unfortunately I couldn't see how the lines where run :(

But the HKS EVC you have is able to increase or reduce boost with revs so that will need to be looked at

IMO the compressor is just not big enough the supply a 3.2 but that doesn't explain mhy boost is in sooner then it is, cam timing would explain it though

  • Like 1

Fairly narrow minded, all you can say is its the turbo. Its rated for over 700hp ffs, if there are no other restirictions it should acheive close to that.

Can u tell me why my engine with a .82 rear housing does not have this issue?

Yep I am narrow minded and talk rubbish. I agree. The best thing about theorising is disagreeing with with myself. I learn a lot from reading other peoples opinions and my own life experience. And I still disagree with most of the things I say as if the everything is just an illusion.

Theory is an illusion in the non physical but the current reality lies with Pete, but soon enough will lie with JEZ then will become Pete's and then will become mine.

Edited by XGTRX

What I didn't think to do while I was driving it was check wastegate pressure, do you remember how the "peak hold" i showed you works ?

It works with the controller off as well, so can I get you to turn off the boost controller by press and holding the bottom button till it beeps then hold the round button till it beeps then take it for a run and report back with the number that comes up at the top of the screen :)

What I didn't think to do while I was driving it was check wastegate pressure, do you remember how the "peak hold" i showed you works ?

It works with the controller off as well, so can I get you to turn off the boost controller by press and holding the bottom button till it beeps then hold the round button till it beeps then take it for a run and report back with the number that comes up at the top of the screen :)

thanks, give it a go tomorrow, just got back from my daily :)

Do you mean "give it a run" to get the revs up ?

Unfortunately I couldn't see how the lines where run :(

But the HKS EVC you have is able to increase or reduce boost with revs so that will need to be looked at

IMO the compressor is just not big enough the supply a 3.2 but that doesn't explain mhy boost is in sooner then it is, cam timing would explain it though

Compressor out of flow could cause the boost drop over revs, i had same issue with the std gt35 compressor.

I see precission rate the turbo at over 700hp tho, i dont know alot about their turbos and if they meet there rated hp.?

Edited by sky30

Compressor out of flow could cause the boost drop over revs, i had same issue with the std gt35 compressor.

I see precission rate the turbo at over 700hp tho, i dont know alot about their turbos and if they meet there rated hp.?

The 62mm Precision CEA compressor seems to have potential for around 74lb/min flow which puts it on par with the GTX3582R and HTA3586 compressors - the compressor (so long as nothing is causing it to work harder than it should) should have plenty more in it... but yeah, that was what I usually used as a hint of if a turbo was struggling to hold boost. I normally identify soaring TIP while tuning by VE falling over and/or detonation becoming an issue and tend to stop trying to get more boost before it becomes a big problem so the only times I've seen issues raising boost is also the times IAT starts going up - or compressor efficiency is plunging.

Those two points set up for XKLABA's comments:

What I didn't think to do while I was driving it was check wastegate pressure, do you remember how the "peak hold" i showed you works ?

This is a good point after XGTRX's comments regarding excessive exhaust manifold pressure possibly causing the wastegate valve to crack open prematurely - if that's the cause then a stiffer spring would potentially delay that a bit and allow a bit more boost to be forced into it, though I don't really like that too much given if exhaust pressure is already that high then the engine's VE will be starting to plummet and things will be getting quite uncomfortable in the engine.... which leads to:

Problem with going off rated HP from a turbo is it is mostly effected by engine efficiency as to how close it gets to its rated HP and engine efficiency is largely influenced by cam timing

Yep - agreed, those thumbsuck power ratings piss me off to a degree, its good for a lot of people but when it gets to the nitty gritty it causes a lot of confusion when people keep falling back to "But it's rated to xxHP - it should be able to make that" or even in some cases "It can't make that, it's not rated to that power!!!".

At a more fundamental level, engine volumetric efficiency is largely to do with the momentum and pressure differential of gases between the intake, the cylinder and the exhaust... cam's obviously have a huge role in that, but if (due to a restriction) the exhaust manifold pressure starts soaring then you can find it becomes increasingly harder for the engine to evacuate the gases involved in the previous cycle meaning for all intents and purposes you have less volume to work with and higher in-cylinder temperatures, then combine that with the BSFC (fuel used, compression, and a variety of other things) and suddenly a "700hp turbo" can make anywhere from 350hp up to 800+hp @ crank when maxed out in different situations. Fun times.

  • Like 2

Yep - agreed, those thumbsuck power ratings piss me off to a degree, its good for a lot of people but when it gets to the nitty gritty it causes a lot of confusion when people keep falling back to "But it's rated to xxHP - it should be able to make that" or even in some cases "It can't make that, it's not rated to that power!!!".

At a more fundamental level, engine volumetric efficiency is largely to do with the momentum and pressure differential of gases between the intake, the cylinder and the exhaust... cam's obviously have a huge role in that, but if (due to a restriction) the exhaust manifold pressure starts soaring then you can find it becomes increasingly harder for the engine to evacuate the gases involved in the previous cycle meaning for all intents and purposes you have less volume to work with and higher in-cylinder temperatures, then combine that with the BSFC (fuel used, compression, and a variety of other things) and suddenly a "700hp turbo" can make anywhere from 350hp up to 800+hp @ crank when maxed out in different situations. Fun times.

Logically, it may be the reason they retarded the cams to solve the initial issues they were having. Yeah and totally agree with not touching the waste gate or boost control until there is a real understanding of what's happening. Piston ring and head gasket sympathy comes to mind.

Why cant you just look at the boost controller and see if its deliberately set that way? I know on my AVCR its very obvious if someone's set the boost to drop off...

Can this be also done by the Haltech Platinum Pro, I think that also has boost control features ?

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