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12307 Posts Member #: 565 Carlos Fandango Burnham-on-Crouch, Essex |
20th Oct, 2011 at 12:30:27pm
the tollerances are pretty big,
Edited by Joe C on 20th Oct, 2011. On 28th Aug, 2011 Kean said:
At the risk of being sigged... Joe, do you have a photo of your tool? http://www.turbominis.co.uk/forums/index.p...9064&lastpost=1 https://joe1977.imgbb.com/ |
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
20th Oct, 2011 at 02:14:18pm
On the two diesel (1749VNT) I've just had apart, soot wasn't really an issue.
Schrödinger's cat - so which one am I ??? |
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8604 Posts Member #: 573 Formerly Axel Podland |
20th Oct, 2011 at 02:41:00pm
I'm reasonably satisfied that a VNT on a rarely used Mini turbo is going to be OK. Now that VNTs are common place and doing 100,000 plus miles on a production diesel, they have to be rugged enough to cope with extreme conditions, including short term high temperatures.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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1849 Posts Member #: 672 The oversills police Oslo, Norway |
20th Oct, 2011 at 03:35:37pm
Isnt Porsche using VNT on petrol engines |
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971 Posts Member #: 3228 Post Whore North of the Netherlands |
20th Oct, 2011 at 03:45:49pm
We had a tolarance issue at work yesterday, read this thread and thought I should make a remark. Would be a shame if you found out the hard way...
Dazed and Confused.... |
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6745 Posts Member #: 828 Post Whore uranus |
20th Oct, 2011 at 04:07:17pm
damn , i just remembered i have a vnt 2259 ...temptation.. Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM |
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6745 Posts Member #: 828 Post Whore uranus |
20th Oct, 2011 at 05:01:49pm
http://www.youtube.com/watch?v=iwAFznIW_Zg
Edited by robert on 20th Oct, 2011. Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM |
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8604 Posts Member #: 573 Formerly Axel Podland |
21st Oct, 2011 at 10:53:36am
Interesting bit about shock waves from my text book:
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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Site Admin 9403 Posts Member #: 58 455bhp per ton 12 sec 1/4 mile road legal mini Sunny Bridgend, South Wales |
21st Oct, 2011 at 04:11:08pm
On 20th Oct, 2011 miniminor63 said:
Isnt Porsche using VNT on petrol engines thats what I was thinking Team www.sheepspeed.com Racing
On 15th May, 2009 TurboDave said:
I think the welsh one has it right! 1st to provide running proof of turbo twinkie in a car and first to run a 1/4 in one!! Is your data backed up?? directbackup.net one extra month free for all Turbo minis members, PM me for detials |
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8604 Posts Member #: 573 Formerly Axel Podland |
21st Oct, 2011 at 05:15:46pm
Porsche do indeed;
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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1849 Posts Member #: 672 The oversills police Oslo, Norway |
21st Oct, 2011 at 05:50:02pm
Thats aftermarket. They use it on brand new ones from the factory. |
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8604 Posts Member #: 573 Formerly Axel Podland |
21st Oct, 2011 at 05:54:19pm
Yep, just using the link to show how the manifolding is done. I assume that the factory must mount it in the same position.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
21st Oct, 2011 at 06:30:56pm
Without getting too bent out of shape, it seems the average head gasket life on this forum is 1k miles. pistons maybe 2k miles, blocks not much longer when the head gasket fails and thrust bearings fail even quicker.
Schrödinger's cat - so which one am I ??? |
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
21st Oct, 2011 at 06:36:42pm
The OEM Porsche setup is like this:
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12307 Posts Member #: 565 Carlos Fandango Burnham-on-Crouch, Essex |
22nd Oct, 2011 at 12:19:01am
bang on!
On 21st Oct, 2011 Rod S said:
Without getting too bent out of shape, it seems the average head gasket life on this forum is 1k miles. pistons maybe 2k miles, blocks not much longer when the head gasket fails and thrust bearings fail even quicker. So 100k on a production diesel seems good - my VNT lasted 65K and that was on a Ford. Can anyone destroy a VNT on a Mini before the rest of the engine ??? No evidence so far :) :) :) On 28th Aug, 2011 Kean said:
At the risk of being sigged... Joe, do you have a photo of your tool? http://www.turbominis.co.uk/forums/index.p...9064&lastpost=1 https://joe1977.imgbb.com/ |
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3588 Posts Member #: 655 Post Whore Northern Ireland |
22nd Oct, 2011 at 12:29:33am
On 18th Oct, 2011 Advantage said:
It is said in the automotive business (where I work) that VNT for gasoline engine are not a valid option as of today. On a gasoline engine, the vanes and added mechanic has to cope with much higher temperatures than with a diesel engine. I have in mind the followings : Gasoline : 1050°C Diesel : 700°C Ever wondered why VW built its hi power TSI with a supercharger AND a turbo if a VNT was available and suitable ? Twice the parts is twice the price and twice the hassle. I would stay clear of VNT's ... except maybe if I got given the turbo for free ! Pretty sure Porsche already offer a VNT petrol setup ? And as others have said. Warranty and durability are paramount on an OEM setup. They have to warranty vehicles for high mileage and all sorts of use or abuse. Mini owners wishing to fit a cheap second hand turbo dont really have those same considerations. And if their TSI setups were so good....everyone wouldnt be crying about them drinking nearly as much oil as petrol. So they didnt get something right there !! And whether petrol or diesel, airflow is airflow. And airflow combined with some fuel is what makes power. So turbo fitments based on overall power/torque potential are still valid regardless of fuel 9.85 @ 145mph
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8604 Posts Member #: 573 Formerly Axel Podland |
22nd Oct, 2011 at 10:28:38am
This was intended to be a discussion about the options to reduce the boost threshold. We seem to keep going back to the suitability of VNTs on petrol engine.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
22nd Oct, 2011 at 10:53:33am
OK, back to the point....
Schrödinger's cat - so which one am I ??? |
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8604 Posts Member #: 573 Formerly Axel Podland |
22nd Oct, 2011 at 11:20:11am
The rev range of a diesel will mean that they do not run much or even any overlap on the cam. Hence a bit more back pressure can be tolerated. A petrol engine at 7-8k is a different matter.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
22nd Oct, 2011 at 11:47:36am
On 22nd Oct, 2011 Paul S said:
The rev range of a diesel will mean that they do not run much or even any overlap on the cam. Hence a bit more back pressure can be tolerated. A petrol engine at 7-8k is a different matter. Good point. On 22nd Oct, 2011 Paul S said:
I expect, but need data to confirm, that the VNT nozzles work both sides of the "normal" nozzle size i.e. they open up bigger as well as close down to bring boost in early. Much like the VVT in my Fez where I see as much benefit at 2k as I do at 7k. The other interesting thing I noticed in the Garrett catalogue is they don'y quote A/Rs on the exhaust turbine but a series of numbers, VNT, VNT1, VNT2, VNT3. Knowing what those numbers mean relative to the A/R on a normal turbine - as the wheel size is pretty much fixed by the first two digits in GT**** - is probably the key to your question. (My GTV1749VNT turbine wheel looks identical to the GT1752 turbine wheel). On 22nd Oct, 2011 Paul S said:
I wonder if Joe could get some TIP data? Where's he gone? Out fixing something else ??? :) Schrödinger's cat - so which one am I ??? |
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12307 Posts Member #: 565 Carlos Fandango Burnham-on-Crouch, Essex |
22nd Oct, 2011 at 01:14:35pm
LOL, been fixing my hangover this morning... oooff!
On 22nd Oct, 2011 Rod S said:
On 28th Aug, 2011 Kean said:
At the risk of being sigged... Joe, do you have a photo of your tool? http://www.turbominis.co.uk/forums/index.p...9064&lastpost=1 https://joe1977.imgbb.com/ |
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8604 Posts Member #: 573 Formerly Axel Podland |
22nd Oct, 2011 at 05:59:56pm
On 22nd Oct, 2011 Rod S said:
The other interesting thing I noticed in the Garrett catalogue is they don'y quote A/Rs on the exhaust turbine but a series of numbers, VNT, VNT1, VNT2, VNT3. Well, if you reassembled your GT1749v nozzle and actuator ring and measured the vane width and gaps at each extreme of the movement, we could make a good guess ! Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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3588 Posts Member #: 655 Post Whore Northern Ireland |
22nd Oct, 2011 at 08:44:03pm
On 22nd Oct, 2011 Paul S said:
This was intended to be a discussion about the options to reduce the boost threshold. We seem to keep going back to the suitability of VNTs on petrol engine. I'm satisfied that the VNT is an option on the A Series. Joe has proved his to work OK and get some miles on it. Let's face it, if anyone could bust a VNT, it would be Joe :) My main concern is still the issue of passing all the exhaust gas though the turbine and creating VE damaging back pressure. As for the TD04L-12T, it is a bit of an oddball, even in single scroll form. Similar compressor wheel size to a GT1548 and a turbine wheel similar to a GT2052. Wheel size does not tell the whole story, but I would imagine it to be slow to spool and that's why they have upgraded it to a twin scroll. On that note. How many have done EGBP testing on their existing setups, and what were the results ? either normal, twin, vnt, anything really 9.85 @ 145mph
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
22nd Oct, 2011 at 09:19:56pm
On 22nd Oct, 2011 stevieturbo said:
On that note. How many have done EGBP testing on their existing setups, and what were the results ? either normal, twin, vnt, anything really Stevie, At the risk of being flamed, I would say slightly less people than the number who have actually put dual widebands on a five port to look at the differences between inner and outer AFRs. Doesn't mean it can't be done, just not many doing it yet :). The price of the technology is coming down all the time at the moment, it's just the will to do it that is lacking. Schrödinger's cat - so which one am I ??? |
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8215 Posts Member #: 90 Post Whore Somewhere around Swindon |
22nd Oct, 2011 at 09:35:32pm
If anyone like me has no idea about the twin scroll turbo i found a great article.
Crystal Sound Audio said:
Why wolfie...you should have your name as Fuckfaceshithead ! "A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools."-Douglas Adams |
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