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Old 03-19-2007, 09:01 PM   #1
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Default VNT25 T25 Turbo

This is a brand new VNT25 Turbo. I bought it with intent to use it on my newest project, but now plans are elsewhere(NA instead of turbo for class reasons). SOOOO this turbo is up for sale. If you havent heard of a VNT turbo here is an article about it.

http://www.thedodgegarage.com/turbo_vnt.html

I would like to get what I paid, which is $500 plus shipping.
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Old 03-20-2007, 02:33 AM   #2
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Interesting turbo design. Corky Bell mentions the VNT (variable nozzle turbine) design a few times in "Maximum Boost" and I figure thats why he used the Aerocharger in his first miata turbo kit. I wonder why this design seems to have fallen by the wayside? I would guess that with the recent thrust to use turbochargers in OEM cars and all the Aftermarket use of them as well, we may see a new surge in engeneering ways to boost on demand as opposed to good ol displacement. I hope so.
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Old 03-20-2007, 02:56 AM   #3
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i heard the new twin turbo bmw 3 series,has a revoluitonary turbo design.
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Old 03-20-2007, 03:05 AM   #4
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id be interested to see how this *revolutionary* turbo works. Probably another VTN design.
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Old 03-20-2007, 03:07 AM   #5
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probally havent saw anny pics or nothing ,just what someone was telling me.sounds like a vtn as far as the kid was explaining it.
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Old 03-20-2007, 04:12 AM   #6
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a new type of vnt turbo is being used by porsche in their newest twin turbo as well.
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Old 03-20-2007, 09:55 AM   #7
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Quote:
Originally Posted by turbopezz View Post
i heard the new twin turbo bmw 3 series,has a revoluitonary turbo design.

yeah its called one small turbo, and one slightly larger turbo.
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Old 03-27-2007, 03:48 AM   #8
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is that so you achieve more balance as far as power across all rpms?
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Old 03-27-2007, 12:52 PM   #9
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It will allow you to basically have the equivilant of a very small fast spooling turbo at low rpms, and a much larger one at higher rpms, so you never get that point where the turbo is "choking off the motor" because its not big enough. Max boost for this turbo is around 16psi reliably.
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Old 03-27-2007, 02:37 PM   #10
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Quote:
Originally Posted by Braineack View Post
yeah its called one small turbo, and one slightly larger turbo.
yes, but the way they implemented it is different than what had been done in the past. previously people had put the two turbos inline so that one blew through the other, which means once your small turbo is out of it's efficiency range you are still running the **** out of it.

BMW is running the turbos parallel with electronically controlled valves on both the turbines (WG) and the compressors so that once the small turbo starts to run out of air it is effectively cut off from the system and the large one takes over. Their system allows for tuning of the crossover point so it is seemless and feels like a larger engine instead of one relying on snails.

I've driven one of the 535D turbo diesels with this setup and I have to tell you it was impressive as hell.

edit* the waste gate on the small turbo is actually a valve not a wastegate... it kills the exhaust flow pre-turbo and routes it all to the larger turbo. I have a system schematic of this somewhere. I'll post it if/when I find it.
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Old 03-27-2007, 03:23 PM   #11
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The 335i uses two, same-sized turbos in parallel.

The 535d uses two sequential turbos of different sizes.

Two entirely different setups.
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Old 03-27-2007, 03:37 PM   #12
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hmmm, i need to read up agian, i thought they were both the 525d design....but then again i hate reading and just enjoy the pictures when bimmer mag comes.
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Old 03-27-2007, 04:00 PM   #13
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Quote:
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then again i hate reading and just enjoy the pictures when bimmer mag comes.
yeah, sure you're talking about a bimmer mag there bud
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Old 03-27-2007, 04:37 PM   #14
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you got me, it's playgirl and bear
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Old 03-28-2007, 12:45 AM   #15
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I don't want to hear about anyone in Playgirl that goes by the nickname "Bear."

335i engine...two small turbos:

535d engine...one small and one large:

WTF are we having this discussion in a for-sale sub-forum?
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Old 03-28-2007, 09:47 AM   #16
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damn ive seen both those pics too.


and if we cant discuss things here, where can we discuss them?
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