2560 vs 2860 boost numbers... - Page 2 - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 01-07-2009, 01:36 PM   #21
Junior Member
 
Join Date: Jan 2007
Location: EXTREME Southern Illinois
Posts: 281
Total Cats: 0
Default

Quote:
Originally Posted by Braineack View Post
1. A steep surge limit line indicates that the turbo will produce high boost pressures at low cfm before surge is produced. A surge line that leans sharply to the right, indicates that the turbo will not work at high boost pressures at low airflow rates.

2 & 3. It doesn't sound like you are calculating and reading the map correctly. What turbo? what power goal? Try reading turbobygarrett.com "turbo tech 103"
I was using the lb/min calculator here: Ray Hall Turbocharging - Java turbocharger flow map calculator

RPM points were 3000-4000-5000-6000-7000
VE was 80% across the board
Compressor efficiency was whatever my map said it would be when i punched in the boost and got a flow calculation.
Bore was 3.307in
Stroke was 3.346in
Cyl 4
Air Temp 20C
Intercooler Efficiency 70%

Basically I put in the values initially shaped on a T3-60 map, then used the lb/min numbers to cross reference it to a GT2560 map and make some adjustments.

My aim was to get the torque up to ~200lb-ft as fast as possible and hold it there as long as possible without heat-soaking my old Flying Miata intercooler.
DammitBeavis is offline   Reply With Quote
Old 01-07-2009, 01:44 PM   #22
Elite Member
iTrader: (2)
 
Mobius's Avatar
 
Join Date: May 2008
Location: Portland, Oregon
Posts: 3,178
Total Cats: 267
Default my calcs

I put together this spreadsheet a while back to help me decide between the 2560 and 2860rs. Take a look and see if it helps.
Attached Files
File Type: xls turbocalcs2.xls (827.5 KB, 122 views)
Mobius is offline   Reply With Quote
Old 01-07-2009, 01:49 PM   #23
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,900
Total Cats: 1,793
Default





This assumes 18psi to make 300rwhp. Will it take 18psi to make 300rwhp...I dunno. The math in the turbo tech 103 is pretty good.

this is why I'm found of the 2871:

Braineack is offline   Reply With Quote
Old 01-07-2009, 02:42 PM   #24
Elite Member
iTrader: (2)
 
Mobius's Avatar
 
Join Date: May 2008
Location: Portland, Oregon
Posts: 3,178
Total Cats: 267
Default

RE: 18psi for 300hp, I built the spreadsheet from the tech103 article and Corky's book. I then scaled/fudge factored so that the numbers matched several real-world examples I'm aware of for 240hp at 12psi. 18psi for 300hp is what came out of that.
Mobius is offline   Reply With Quote
Old 01-07-2009, 02:48 PM   #25
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,900
Total Cats: 1,793
Default

there are so many factors, it's really impossible and wrong to say 18psi = 300rwhp. Remember Paul has made both 270rwhp and 300rwhp at 14psi on his 2560 all thing but the intake manifold being equal.
Braineack is offline   Reply With Quote
Old 01-07-2009, 03:06 PM   #26
Junior Member
 
Join Date: Jan 2007
Location: EXTREME Southern Illinois
Posts: 281
Total Cats: 0
Default

Your calculators are more generous with airflow/psi than mine were. I was showing 22psi was necessary for [email protected]

According to your numbers I would still have some headroom left from ~4000 to ~6000 on the 2560 to bump up the torque even more.
DammitBeavis is offline   Reply With Quote
Old 01-07-2009, 03:08 PM   #27
Elite Member
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 8,797
Total Cats: 248
Default

Braineack, what's the basis behind the red dots? Reference points to different RPMs? I might try to do a map like that for different boost and RPMS for my GT3271. Would be interesting for sure.
patsmx5 is offline   Reply With Quote
Old 01-07-2009, 03:14 PM   #28
Junior Member
iTrader: (6)
 
Join Date: Jun 2008
Location: Lansdale, PA
Posts: 462
Total Cats: 3
Default

Quote:
Originally Posted by patsmx5 View Post
Braineack, what's the basis behind the red dots? Reference points to different RPMs? I might try to do a map like that for different boost and RPMS for my GT3271. Would be interesting for sure.
https://www.miataturbo.net/forum/t23229/

They are plots to show where on the compressor map the flow would fall at any given pressure ratio.
BradC is offline   Reply With Quote
Old 01-07-2009, 03:26 PM   #29
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,900
Total Cats: 1,793
Default

Quote:
Originally Posted by patsmx5 View Post
Braineack, what's the basis behind the red dots? Reference points to different RPMs? I might try to do a map like that for different boost and RPMS for my GT3271. Would be interesting for sure.
Squirrel Performance - Turbo Calculator Version 4
Braineack is offline   Reply With Quote
Old 01-07-2009, 03:34 PM   #30
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,900
Total Cats: 1,793
Default

Quote:
Originally Posted by DammitBeavis View Post
Your calculators are more generous with airflow/psi than mine were. I was showing 22psi was necessary for [email protected]

According to your numbers I would still have some headroom left from ~4000 to ~6000 on the 2560 to bump up the torque even more.

see what Paul did to run 300rwhp @ 14psi and then 310rwhp @ 17psi, the turbo is completely spent.

Braineack is offline   Reply With Quote
Old 01-07-2009, 03:37 PM   #31
Elite Member
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 8,797
Total Cats: 248
Default

My turbo at 16 PSI



My turbo at 21 PSI:





My turbo at 24 PSI:





My turbo at 11 PSI, where I'm at now:

patsmx5 is offline   Reply With Quote
Old 01-07-2009, 03:54 PM   #32
Junior Member
 
Join Date: Jan 2007
Location: EXTREME Southern Illinois
Posts: 281
Total Cats: 0
Default

That's very encouraging.
According to Paul's sig he has better exhaust flow than I will which means I probably won't hit that kind of topend power. But it looks like he ran a flat amount of boost. I've got a ported/polished head with big backcut valves, so hopefully I can hold ~250lb/ft through the midrange with a strategically shaped boost curve.

What kind a fuel was that on?
DammitBeavis is offline   Reply With Quote
Old 01-07-2009, 04:02 PM   #33
y8s
2 Props,3 Dildos,& 1 Cat
iTrader: (8)
 
y8s's Avatar
 
Join Date: Jun 2005
Location: Fake Virginia
Posts: 19,038
Total Cats: 407
Default

I like the 2871-2 for 300-350 hp...
y8s is offline   Reply With Quote
Old 01-07-2009, 04:02 PM   #34
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,900
Total Cats: 1,793
Default

93 octane, keep in mind his IM as well, that made all the difference in the world for his torque curve.
Braineack is offline   Reply With Quote
Old 01-07-2009, 05:57 PM   #35
Elite Member
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 8,797
Total Cats: 248
Default

Quote:
Originally Posted by Braineack View Post
93 octane, keep in mind his IM as well, that made all the difference in the world for his torque curve.
No kidding. Where's all the badass intake manifolds that are supposed to be put into production this winter?....

And looks my turbo's pretty efficient for a 1.8L.
patsmx5 is offline   Reply With Quote
Old 01-07-2009, 05:59 PM   #36
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,900
Total Cats: 1,793
Default

like this one?

Name:  IntakeManifold001.jpg
Views: 45
Size:  164.6 KB

I know of two other 1.6Ls that have IMs on the way.
Braineack is offline   Reply With Quote
Old 01-08-2009, 04:51 AM   #37
Elite Member
iTrader: (15)
 
Join Date: Sep 2007
Location: Incline Village, NV
Posts: 2,073
Total Cats: 5
Default

Brain, whats the deal with the front temp sensor broken off? How are you controlling the fan?
thesnowboarder is offline   Reply With Quote
Old 01-08-2009, 06:06 AM   #38
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,372
Total Cats: 1,334
Default

Quote:
Originally Posted by Braineack View Post
like this one?



I know of two other 1.6Ls that have IMs on the way.
Plug your IAT sensor in
Savington is offline   Reply With Quote
Old 01-08-2009, 10:13 AM   #39
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,900
Total Cats: 1,793
Default

Quote:
Originally Posted by thesnowboarder View Post
Brain, whats the deal with the front temp sensor broken off? How are you controlling the fan?
I use MS to control the fans, that thermoswitch is now a simple plug to prevent coolant from sparying all over the place.

Quote:
Originally Posted by Savington View Post
Plug your IAT sensor in
I use that spare AIT to plug the bung, I have yet to buy a real 3/8" plug for it. The AIT sensor is connected and installed out of the engine bay just after the IC.
Braineack is offline   Reply With Quote
Old 01-08-2009, 11:13 AM   #40
y8s
2 Props,3 Dildos,& 1 Cat
iTrader: (8)
 
y8s's Avatar
 
Join Date: Jun 2005
Location: Fake Virginia
Posts: 19,038
Total Cats: 407
Default

i might have a 3/8 plug in my basement. remind or come by tonight and we'll look.
y8s is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 59 12-15-2017 09:00 PM
LucaCarMods's Boosted Dutch Miata Build! LucaCarMods Build Threads 11 02-14-2016 07:13 AM
Back to Stock Part Out!! Turbo Parts, MS2 Enhanced 01-05, Suspension, and MOAR! StratoBlue1109 Miata parts for sale/trade 16 10-02-2015 10:39 AM
Going back to stock. Need some 1.6 parts. Trent WTB 2 10-01-2015 01:15 PM
Bad head gasket or ? shooterschmidty Engine Performance 8 09-30-2015 11:28 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 07:11 AM.