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 8604 Posts Member #: 573 Formerly Axel Podland |
22nd Oct, 2011 at 10:34:18pm
On 22nd Oct, 2011 stevieturbo said:
How many have done EGBP testing on their existing setups, and what were the results ? either normal, twin, vnt, anything really We have the instrumentation to measure and log EGBP on the Miglia Turbo, just not had the track/RR time to get any data. 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 |
23rd Oct, 2011 at 11:53:19am
On 22nd Oct, 2011 Rod S said:
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. It wasnt meant in any way as a dig. it was a genuine question. Ive only ever tested two cars myself. One my old RV8 twin turbo years ago, and more recently a friends approx 600banana 4cyl turbo. Well 3 actually, Ive done my existing car with an older exhaust, but it's n/a so doesnt really count. Although amazingly with two collapsed middle silencers, I did see as much as 14psi !!! just at the left side collector. Even more strangely, I didnt even notice any difference in performance. It can cost very little to test. Weld a small brake pipe fitting onto the manifold ( or drill/tap ). Run a short length of brake pipe to dissipate heat and then just stick a rubber hose onto it and a pressure gauge. Gauges can be bought on egay for around £5 or from any pneumatics type place. I joust bought some from egay, fluid filled, think they were about £7 each I dont remember exactly, but my RV8 was I think around 25psi EGBP at 15psi boost. The other car more recently was around 52psi EGBP at 35psi boost. I was actually expecting the latter to be much higher. Edited by stevieturbo on 23rd Oct, 2011. 9.85 @ 145mph
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 (2)[/url] by [url=https://www.flickr.com/photos/150672766@N03/]Rod Sugden[/url], on Fli) 5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
23rd Oct, 2011 at 12:28:04pm
On 23rd Oct, 2011 stevieturbo said:
It can cost very little to test. Weld a small brake pipe fitting onto the manifold ( or drill/tap ). Run a short length of brake pipe to dissipate heat and then just stick a rubber hose onto it and a pressure gauge. Gauges can be bought on egay for around £5 or from any pneumatics type place. I joust bought some from egay, fluid filled, think they were about £7 each Actually I was thinking along similar lines but connecting to pressure transmitters instead. With the IOx or IOx-OEM, I've got the ability to log it all through the MS2 - the pressure transmitters, same as the ones used in the MS2 itself, are only ~£10 and are good for 1.5bar positive (~27psi) and the higher reading ones aren't that much more expensive. I actually want to measure and log the pressures in my wideband sample chambers, but that's for another reason. :) Schrödinger's cat - so which one am I ??? |
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 6745 Posts Member #: 828 Post Whore uranus |
23rd Oct, 2011 at 02:50:34pm
On 23rd Oct, 2011 stevieturbo said:
On 22nd Oct, 2011 Rod S said:
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. It wasnt meant in any way as a dig. it was a genuine question. Ive only ever tested two cars myself. One my old RV8 twin turbo years ago, and more recently a friends approx 600banana 4cyl turbo. Well 3 actually, Ive done my existing car with an older exhaust, but it's n/a so doesnt really count. Although amazingly with two collapsed middle silencers, I did see as much as 14psi !!! just at the left side collector. Even more strangely, I didnt even notice any difference in performance. It can cost very little to test. Weld a small brake pipe fitting onto the manifold ( or drill/tap ). Run a short length of brake pipe to dissipate heat and then just stick a rubber hose onto it and a pressure gauge. Gauges can be bought on egay for around £5 or from any pneumatics type place. I joust bought some from egay, fluid filled, think they were about £7 each I dont remember exactly, but my RV8 was I think around 25psi EGBP at 15psi boost. The other car more recently was around 52psi EGBP at 35psi boost. I was actually expecting the latter to be much higher. my rv8 was 30 at 15 psi , but it was a two stage system with a bit too small 2nd stage . Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM |
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8604 Posts Member #: 573 Formerly Axel Podland |
23rd Oct, 2011 at 03:42:37pm
I would expect about 25-30psi EGBP on 15psi boost on a wastegated system. The question is how much that goes up, if at all, when using a VNT and no wastegate. Hopefully Joe will be able to tell us.
Edited by Paul S on 23rd Oct, 2011. Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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6745 Posts Member #: 828 Post Whore uranus |
23rd Oct, 2011 at 05:35:20pm
On 22nd Oct, 2011 Paul S said:
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 ! gt2259,pics ... 
Edited by robert on 23rd 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 |
23rd Oct, 2011 at 05:49:05pm
That's very interesting Robert. Thanks.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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 12307 Posts Member #: 565 Carlos Fandango Burnham-on-Crouch, Essex |
23rd Oct, 2011 at 05:57:46pm
yep, .84 will be the A/R, the vanes will then make it boost like a smaller A/R at lowwer openings.
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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6745 Posts Member #: 828 Post Whore uranus |
23rd Oct, 2011 at 06:05:37pm
by inducer joe ,do you mean the bigger diameter of the wheel ? how big is it ? Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM |
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
23rd Oct, 2011 at 06:06:43pm
On 23rd Oct, 2011 Joe C said:
yep, .84 will be the A/R, the vanes will then make it boost like a smaller A/R at lowwer openings. my big one (with the 2259 compressor) is marked .69iirc, my turbine wheel looks very different though, mine had a considerably bigger inducer. If they are A/R numbers, why does the catalogue quote VNT numbers ??? http://www.turbomaster.info/eng/catalogs/m...tt&pagina=GT17V Ok, it's not a genuine Garrett document but it definately doesn't quote a traditional number in the AFR column :) And if they are A/R numbers on the casting, is that vanes open/closed/part way ??? Schrödinger's cat - so which one am I ??? |
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12307 Posts Member #: 565 Carlos Fandango Burnham-on-Crouch, Essex |
23rd Oct, 2011 at 06:13:05pm
in this one you can see one of them listed as A/R .64
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 |
23rd Oct, 2011 at 06:30:45pm
I guess that although the VNT has vanes that create a series of individual nozzles, there is still the throat of the inlet that constitutes the conventional "A" component and sets the velocity within the volute. 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 |
23rd Oct, 2011 at 07:38:15pm
Just a wild thought.....
Schrödinger's cat - so which one am I ??? |
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10 Posts Member #: 9558 Member Netherlands |
14th Nov, 2011 at 05:48:34pm
Reading this last link about twin scroll turbos there is a lot of emphasis on manifold design, primairy length etc.
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8604 Posts Member #: 573 Formerly Axel Podland |
14th Nov, 2011 at 05:53:07pm
OEMs have to balance packaging and cost against marginal gains in performance.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
14th Nov, 2011 at 06:02:04pm
Could you use different harmonics (so different lengths) for the 2 cylinders of a pair?
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8604 Posts Member #: 573 Formerly Axel Podland |
14th Nov, 2011 at 06:08:26pm
I could.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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12307 Posts Member #: 565 Carlos Fandango Burnham-on-Crouch, Essex |
14th Nov, 2011 at 06:26:55pm
nope, hopfully be fitting the gaue at the weekend. 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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520 Posts Member #: 2093 Post Whore Grenoble, France |
5th Jan, 2012 at 04:30:01pm
Hi Paul,
std 998 A+, g295, MD266, RHF4, 109hp @0.8bar/5400rpm |
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8604 Posts Member #: 573 Formerly Axel Podland |
6th Oct, 2014 at 06:06:58pm
3 years on and I'm still trying to decide which way to go, this time on my lads car Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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 7265 Posts Member #: 1268 The Boom Boom speaker Police! Essex |
6th Oct, 2014 at 09:23:43pm
Which ones are you looking at Paul? There's a lot of 2256v's for not too much cash. In the 13's at last!.. Just |
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8604 Posts Member #: 573 Formerly Axel Podland |
7th Oct, 2014 at 08:07:23am
I think that the GT1749v would be best suited.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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7265 Posts Member #: 1268 The Boom Boom speaker Police! Essex |
7th Oct, 2014 at 08:48:02am
http://pages.ebay.com/link/?nav=item.view&...id=251669585114
In the 13's at last!.. Just |
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8604 Posts Member #: 573 Formerly Axel Podland |
7th Oct, 2014 at 09:27:47am
Thanks Gary,
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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 2909 Posts Member #: 83 Post Whore Glasgow, Scotland |
7th Oct, 2014 at 11:45:07am
paul if it helps, i rebuilt the 2260v in my bmw using chinese turbine wheel and bearing kit. 2 years daily use and its still fine. didnt balance it either. I know your a man who likes to do things right, but if you can pick up a knackered core and rebuild it, it may give you a cheap ish unit to test and play with. turbo 16v k-series 11.9@118.9 :)
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