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My car crushing lap record on Swedens no 1 track

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Old 07-10-2014, 06:26 PM
  #106  
URG8RB8
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OK, will do. Thanks!
Old 07-10-2014, 07:36 PM
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George D
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OT a bit, but good article easily demonstrating the differences of Garrett vs Precision. Not a big deal, but worthy of a quick read. I like the Precision's performance in my car, but did want to use a Garrett. We traded my old Turbonetics GTK 650 with a .82 for the Precision 6262 .68.

If/when this turbo shows any issues, a Garrett will likely replace it.

G
Old 07-10-2014, 08:51 PM
  #108  
A.Wayne
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Originally Posted by Duke
"Upgrading" from a GTX turbo? Hmmm I'm veeery sceptical From what I've seen of the Precision internal parts they cannot be compared to a GT/GTX turbo. And I won't go over 750 hp so I will stay with this turbo
The response time on the new precision is much better than the GTX while matching the power numbers. We did some back to back testing 2 yrs ago with them.

If you get a chance to compare the new ones are worth a look in ...
Old 07-10-2014, 09:40 PM
  #109  
333pg333
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Originally Posted by A.Wayne
The response time on the new precision is much better than the GTX while matching the power numbers. We did some back to back testing 2 yrs ago with them.

If you get a chance to compare the new ones are worth a look in ...
When you say 'much quicker' what are you talking? I don't have my logs to hand but I wonder just how much more linear another turbo might be. With a track only car between those normal rpms I don't think we would need to be a lot more responsive than they are already. Gustaf and I share almost the same turbo although he runs higher c/r than our car. My impression is that I wouldn't want it to kick in much earlier than it already does. See either of our videos for visual confirmation.

https://www.youtube.com/watch?v=YCA8...ature=youtu.be


Last edited by 333pg333; 07-10-2014 at 10:19 PM.
Old 07-10-2014, 09:49 PM
  #110  
George D
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http://www.turbodirect.co.za/site/in...=778&Itemid=21

Weird, I posted the link. Here is the "quick read" article with pictures.
Old 07-10-2014, 09:58 PM
  #111  
George D
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Originally Posted by A.Wayne
The response time on the new precision is much better than the GTX while matching the power numbers. We did some back to back testing 2 yrs ago with them.

If you get a chance to compare the new ones are worth a look in ...
The Precision is MUCH better than the GTK 650 previously used. Response time, especially below 4K is immensely superior. When at higher RPM's there isn't really lag as I'm accustomed, more like a linear response towards max boost.

We are changing how the TEC/Boost controller, and waste gate communicates. Instead of fuel cut, the limp mode will now be at 6psi. The locking connection on the BC clip to TEC broke, and a few times it's come apart. Fuel cut happens around 3K, so the TEC is seeing over 17psi by then...Fixed the issue, but I'd prefer a limp low boost mode vs the immediate SHUT DOWN shudder...Scared the CRAP out of my brother while HE was driving. Thankfully I was the passenger and knew how to remedy.

G
Old 07-11-2014, 03:58 AM
  #112  
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Originally Posted by Duke
"Upgrading" from a GTX turbo? Hmmm I'm veeery sceptical From what I've seen of the Precision internal parts they cannot be compared to a GT/GTX turbo.
Agreed. In fact I would steer clear from Precision turbos.
Old 07-11-2014, 04:38 AM
  #113  
Dutch944
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True, Gustaf, Precision cannot be compared because they are superior to the GT/GTX parts..
Old 07-11-2014, 05:04 AM
  #114  
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Lol... you tell us when your engine is running, ok?
Old 07-11-2014, 05:18 AM
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Dutch944
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I will!
Old 07-11-2014, 05:18 AM
  #116  
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This dissection of Precision/Garrett would make me steer clear of precision turbos..

http://www.turbodirect.co.za/site/in...d=26&Itemid=20

This specific Precision shaftwheel’s blades measure 1.4mm thick and this specific component is made in China by a company called Worldturbocharger, this company is well known for manufacturing “copy” products of OEM original Garrett, KKK, IHI, Holset etc – this company uses a material called K18 for the turbine head, which is a steel derivative with a high thermal ceiling, but by no means anywhere near the same quality as the Inconel 713LC material used by Garrett, KKK or Holset, hence the thicker blades on the Precision turbine, thicker blades simply mean more weight, and for any component which relies on its ability to accelerate, weight is not great. The shaft also appears to have been friction welded onto the turbine head.
Precision is a company that up until recently was really just a distributor of Garrett turbo’s. They would take Garrett turbo’s and resell them, mainly focusing on the aftermarket scene. Then they started to modify Garrett turbo’s and openly advertise how their turbo’s were out performing standard Garrett turbo’s. As you can guess Garrett wasn’t happy about that. You would have to assume Precision as a company knew what they were doing. We have all heard the saying: “you shouldn’t crap where you sleep”. Garrett then cut off precision as a supplier.
Old 07-11-2014, 05:31 AM
  #117  
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Luckily mine is a journal bearing..
Old 07-11-2014, 05:40 AM
  #118  
Duke
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Originally Posted by 333pg333
When you say 'much quicker' what are you talking? I don't have my logs to hand but I wonder just how much more linear another turbo might be. With a track only car between those normal rpms I don't think we would need to be a lot more responsive than they are already. Gustaf and I share almost the same turbo although he runs higher c/r than our car. My impression is that I wouldn't want it to kick in much earlier than it already does. See either of our videos for visual confirmation.

https://www.youtube.com/watch?v=YCA8...ature=youtu.be

Porsche 944 Turbo GTR lap record on Mantorp Park 1:19.348 - YouTube
Yes I couldn't wish for better response than with the current setup. And this is with the large turbine housing. It was my old engine that had high CR, this one is below 9.

Note that the car is just running 1.0-1.1 bar of boost in the video. With 1.2-1.3 bar I saw a reduction in acceleration times of 10%. Would be interesting in the name of science to turn it up to "11" but since the car obviously is quick enough for lap records as is why bother

I need to tune the driver (me)
Old 07-11-2014, 09:59 AM
  #119  
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Originally Posted by Voith
This dissection of Precision/Garrett would make me steer clear of precision turbos..

http://www.turbodirect.co.za/site/in...d=26&Itemid=20
Thanks for the link - definitely an interesting read. I'm glad I use Garrett GT turbos and a comparison test like this makes me happy that I'm a Garrett dealer
Old 07-11-2014, 11:14 AM
  #120  
URG8RB8
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Thanks for the link and making me feel secure about my decision to stay with Garrett.


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