Canard Community Forum  

Go Back   Canard Community Forum > Firewall Backward and Forward > Turbo or Super Charging
FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #16  
Old 11-02-2005, 01:38 PM
no4 no4 is offline
Member
 
Join Date: May 2004
Location: A small island, somewhere in the South Pacific
Posts: 119
Default

Hi Mike and everyone,
VE.
The factors affecting ve must be:manifold pressure, valve number/size/movement/duration combined with camshaft timing, cylinder capacity, rpm, and the exhaust system.
At sea level, a normaly aspirated motor, should get 75%, and a multi valve maybe 85%.
A turbo should get at least over 85%.
At 25,000 feet the atmospheric pressure is about 11 inches. Thus the pressure ratio across the two manifolds is greatly increased.
So, You have above 25" manifold pressure, one big fat valve either side which should overlap, big old cylinders, and not much except a turbine in the exhaust, sitting in 11" of atmosphere.
I'd be willing to say that I think your ve should be above 90% and thus your calculations should be valid.

Attached are some twin turbo photo's.
The beast on the chain is a Nissan RB26DETT or twin turbo 2.6 to you. This one is in drag trim of an alleged 1300 hp at 13,000 rpm in a Godzilla Skyline. One of those turbo's should be as big as a Garrett T-61.
http://www.exvitermini.com/


The other three are photos of a twin turbo kit for the new Nissan 350Z. If you choose to go twin turbo they would be of a similar size to these.
http://www.airpowersystems.com.au/350z/turbo/turbo.htm

Have a look at an old Nissan 300ZX twin turbo, it has a very good set up.
All the best.
Attached Thumbnails
Click image for larger version

Name:	stg1eng.jpg
Views:	76
Size:	274.9 KB
ID:	1504  Click image for larger version

Name:	lh_3_4_front.jpg
Views:	57
Size:	49.8 KB
ID:	1505  Click image for larger version

Name:	lh_3_4_rear.jpg
Views:	66
Size:	58.0 KB
ID:	1506  Click image for larger version

Name:	350Z_twin_turbo_kit.jpg
Views:	49
Size:	71.0 KB
ID:	1507  

Last edited by no4 : 11-02-2005 at 01:55 PM.
Reply With Quote
  #17  
Old 11-02-2005, 03:21 PM
Dust's Avatar
Dust Dust is offline
Super Moderator
 
Join Date: Apr 2004
Location: Troy, Michigan
Posts: 7,963
Default

I just think it may be a little more complicated than that. I think by tuning the intake and exhaust for 2800 rpm i can affect the VE.

Also, whether under boost or not the system is always under pressure, albiet it ambient.

have you reviewed the spreadsheet? VE has a large impact and the Garrett aviation turbo guy agreed
__________________
Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

maker of wood, fiberglass, foam dust, metal bits and one day a Cozy will pop out and swiftly whisk me from meeting old friends and family to adventures throughout the world
Reply With Quote
  #18  
Old 11-02-2005, 06:09 PM
Kumaros's Avatar
Kumaros Kumaros is offline
It's all Greek to me
 
Join Date: Aug 2004
Location: Athens, Greece
Posts: 805
Default Stock turbo for TSIO-360 ?

Mike, what are the specs of the stock turbo for the TSIO-360 and why can't you just use that and be done with it?
Kumaros
It's all Greek to me
Reply With Quote
  #19  
Old 11-02-2005, 06:46 PM
Dust's Avatar
Dust Dust is offline
Super Moderator
 
Join Date: Apr 2004
Location: Troy, Michigan
Posts: 7,963
Default

heh heh heh - NO NO NO - i want to normalize to 25000, not 18000

hh heh heh
__________________
Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

maker of wood, fiberglass, foam dust, metal bits and one day a Cozy will pop out and swiftly whisk me from meeting old friends and family to adventures throughout the world
Reply With Quote
  #20  
Old 11-03-2005, 04:15 PM
MarbleTurtle's Avatar
MarbleTurtle MarbleTurtle is offline
Member
 
Join Date: Apr 2004
Location: Dalton, GA.
Posts: 1,344
Default

I would dissagree about the twin turbo 300Z as a place to start with turbo sizing. The 300Z used small turbos for quick spoolup and acceleration and were not designed for sustained power.

I keep telling DUST to use 100% VE and then look and then search for the turbo map with the highest efficiency in the Pressure ratio zone of atmospheric over 25k... but he don't listen so good.

(Sorry. Watched too many Sopranos re-runs in my hotel. Forgot how much I miss cable!)
__________________
Past performance is no guarantee of future results.
Reply With Quote
  #21  
Old 11-04-2005, 12:13 PM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
Member
 
Join Date: Dec 2004
Location: Canada
Posts: 578
Default

I'd second MT here. The 300ZX TT was lame by todays standards. Atmo engine was 222hp, turbo 300. Not a very good attempt by Nissan there. The turbos were a joke for WOT as are most OE installations which are sized for high mid range power and minimal turbo lag. Dust will need much larger compressors and turbines at 25K.

The calculated VE for the Conti is around 100%. The headers that can be fitted in the cowling will have no effect on this. (Proper length would be around 80 inch primaries). The tuned intake than can be fitted will also have minimal effect here because the correct length runners (around 29 inches) cannot really be fitted under the cowling IMHO.

I've posted a photo of DGs 600+ hp twin turbo Conti I took at Reno this year. This would be a good setup to copy.
Attached Thumbnails
Click image for larger version

Name:	reno11.jpg
Views:	82
Size:	41.0 KB
ID:	1508  
Reply With Quote
  #22  
Old 11-04-2005, 12:31 PM
Dust's Avatar
Dust Dust is offline
Super Moderator
 
Join Date: Apr 2004
Location: Troy, Michigan
Posts: 7,963
Default

Well, agree with the 80 inches - actually 82 - but my info says also 41 and 20.5 for exhaust.

on the IM - length and volume - i will calculate and try it out

just can't believe that cleaning up the flow will not improve VE - right now it is just 90 degree short t's on both IM and EXhaust.
__________________
Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

maker of wood, fiberglass, foam dust, metal bits and one day a Cozy will pop out and swiftly whisk me from meeting old friends and family to adventures throughout the world
Reply With Quote
  #23  
Old 11-04-2005, 12:51 PM
Dust's Avatar
Dust Dust is offline
Super Moderator
 
Join Date: Apr 2004
Location: Troy, Michigan
Posts: 7,963
Default

Also - redoing all the plumbing has other advantages - twin turbos for twin intercoolers for twin entree into the IM.

Squeezing it all here and there under the cowling and cooling the various parts in various ways - updraft naca for some, armpit, or downdraft for other parts. it all has to get cooled and the stock naca will not do it

So ifin it does not change the VE - OK it will all fit better and if the engine ends up being 100% VE - that is way better than i planned on.

and hey - rv - appreciate the info - know it was difficult to burst my balloon. balloon still flyin for a variety of reasons
__________________
Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

maker of wood, fiberglass, foam dust, metal bits and one day a Cozy will pop out and swiftly whisk me from meeting old friends and family to adventures throughout the world
Reply With Quote
  #24  
Old 11-04-2005, 02:26 PM
Dust's Avatar
Dust Dust is offline
Super Moderator
 
Join Date: Apr 2004
Location: Troy, Michigan
Posts: 7,963
Default

so, 210 hp and 2800 rpm and 22 gph = 100 VE - what would the A/F ratio be?

also - rv and burns came up with the exact same 82 inches for the optimum exhaust length - totally cool, i go with 20.5 - a quarter wave length - wait a minute - thats what you call an antenna.
__________________
Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

maker of wood, fiberglass, foam dust, metal bits and one day a Cozy will pop out and swiftly whisk me from meeting old friends and family to adventures throughout the world
Reply With Quote
  #25  
Old 11-04-2005, 03:06 PM
StRaNgEdAyS's Avatar
StRaNgEdAyS StRaNgEdAyS is offline
Member
 
Join Date: May 2004
Location: New South Wales Australia
Posts: 490
Default

Quote:
Originally Posted by Dust
totally cool, i go with 20.5 - a quarter wave length - wait a minute - thats what you call an antenna.
Actually you are almost bang on with the comparison there. The movement of air does have wave characteristics just like radio. Air is just another fluid, see how water moves?
Quote:
Originally Posted by Dust
just can't believe that cleaning up the flow will not improve VE - right now it is just 90 degree short t's on both IM and EXhaust.
the reason for that is the gas is under pressure and as such it's still gonna flow pretty much the same with the limited space you have.
If you had more room to play with and you could fit a tuned length set of pipes in there you may see an improvement.
Reply With Quote
  #26  
Old 11-04-2005, 06:28 PM
no4 no4 is offline
Member
 
Join Date: May 2004
Location: A small island, somewhere in the South Pacific
Posts: 119
Default

BLIMEY!
A couple of years ago, Dust didn't sound like he knew a carburettor from a camshaft, and now he's quoting quarter wave length exhaust manifold lengths!!
I'm mightily impressed by that gem!
How did you get to 82 " in the first place?

Last edited by no4 : 11-04-2005 at 06:43 PM.
Reply With Quote
  #27  
Old 11-04-2005, 07:10 PM
MarbleTurtle's Avatar
MarbleTurtle MarbleTurtle is offline
Member
 
Join Date: Apr 2004
Location: Dalton, GA.
Posts: 1,344
Default

Quote:
Air is just another fluid, see how water moves?
Uhmm... I'm pretty sure air is a gas!
__________________
Past performance is no guarantee of future results.
Reply With Quote
  #28  
Old 11-04-2005, 07:47 PM
no4 no4 is offline
Member
 
Join Date: May 2004
Location: A small island, somewhere in the South Pacific
Posts: 119
Default

Three states of matter, solid, liquid, gas. Both gas and liquid are fluid, as in they flow.
Reply With Quote
  #29  
Old 11-04-2005, 11:38 PM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
Member
 
Join Date: Dec 2004
Location: Canada
Posts: 578
Default

Quote:
Originally Posted by no4
Three states of matter, solid, liquid, gas. Both gas and liquid are fluid, as in they flow.
All right, I've been waiting for a suitable chance to use the icon for months now... solid, liquid or gas?
Reply With Quote
  #30  
Old 11-05-2005, 05:18 AM
StRaNgEdAyS's Avatar
StRaNgEdAyS StRaNgEdAyS is offline
Member
 
Join Date: May 2004
Location: New South Wales Australia
Posts: 490
Default

Perhaps some examples would be in order where the fluid and wave forming properties of air come in.
Have you ever driven over an often used dirt road? Have you noticed the wave like patterns in the middle?
These are formed by the air passing over the surface in small turbulent waves at a certain frequency generated by the consistant speed of the traffic.
Have you ever stood up in the mountains and watched the mist/fog rolling around in the foothills? Have you ever noticed the way it flows around and through the valleys etc.?
The study of flow (air or water) over surfaces is called Fluid Dynamics, this is where we get the term Computaional Fluid Dynamics for the software that simulates and graphically represents the flow of air (or water) over a surface.
The BIG difference between liquid and gaseous fluid states is compressability. Liquids are not compressable, whereas gases are.
Attached Thumbnails
Click image for larger version

Name:	Vortex.jpg
Views:	61
Size:	21.5 KB
ID:	1519  
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -4. The time now is 10:05 PM.


Powered by vBulletin® Version 3.6.7
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.