Notices
DIY Turbo Discussion greddy on a 1.8? homebrew kit?

Is the EFR6258 too much for stock engine?

Thread Tools
 
Search this Thread
 
Old Aug 27, 2014 | 07:51 AM
  #21  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

or just control your boost.
Old Aug 27, 2014 | 08:08 AM
  #22  
Leafy's Avatar
Elite Member
iTrader: (1)
 
Joined: Jun 2012
Posts: 9,491
Total Cats: 105
From: NH
Default

Originally Posted by Braineack
or just control your boost.
Well, its hard to keep it to 10psi when you use the stock 14psi actuator.
Old Aug 27, 2014 | 08:12 AM
  #23  
Mech5700's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 476
Total Cats: 13
From: Port Saint Lucie,FL
Default

I will have both the light and medium actuator and it has the EBC as well.
Old Aug 27, 2014 | 11:57 AM
  #24  
JasonC SBB's Avatar
Elite Member
 
Joined: Jul 2005
Posts: 6,420
Total Cats: 84
Default

Originally Posted by Mech5700
From what I can tell, this thing starts building boost just over 2k rpm, is that not quick enough?!
That's not a good measure of spoolup.
Better measures are:
what RPM does it make 5 psi? 10 psi? 15 psi?
How quickly does it go from vacuum to full boost at 3500 RPM? 4000 RPM?
Old Aug 27, 2014 | 12:00 PM
  #25  
Savington's Avatar
Former Vendor
iTrader: (31)
 
Joined: Nov 2006
Posts: 15,442
Total Cats: 2,106
From: Sunnyvale, CA
Default

Originally Posted by JasonC SBB
How quickly does it go from vacuum to full boost at 3500 RPM? 4000 RPM?
It will be difficult/impossible to match the EFR here. The trick turbine wheel reduces rotating inertia and lets the wheel spin up fast. There's no way a 2560R car matches the response. A 2554R car might come close, but give up 100whp on the top end.
Old Aug 27, 2014 | 12:01 PM
  #26  
Leafy's Avatar
Elite Member
iTrader: (1)
 
Joined: Jun 2012
Posts: 9,491
Total Cats: 105
From: NH
Default

rpm is a terrible unit for spool, miliseconds is much better. Over 4k aint nothing going to spool faster than an EFR I dont care how small it is.

Boost threshold wise, thats the rear question. yeah at 2krpms in 5th my 6758 can make a copule psi, got to give it a second though. But its still able to make stock block breaking cylinder pressure by 3.5krpms.
Old Aug 27, 2014 | 12:27 PM
  #27  
Mech5700's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 476
Total Cats: 13
From: Port Saint Lucie,FL
Default

Here is some spool data I found on the collective spool data thread:

https://www.miataturbo.net/showthread.php?p=1109010&styleid=22

Post 203 and 218
Old Aug 27, 2014 | 01:02 PM
  #28  
thenuge26's Avatar
Elite Member
iTrader: (2)
 
Joined: Aug 2012
Posts: 3,267
Total Cats: 239
From: Indianapolis
Default

It may be more work than you're looking for, especially as new it isn't much cheaper than a 6258, but it might be worth looking into the Focus ST stock turbo: https://www.miataturbo.net/diy-turbo...ler-efr-79947/
Old Aug 27, 2014 | 01:10 PM
  #29  
Mech5700's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 476
Total Cats: 13
From: Port Saint Lucie,FL
Default

That is pretty interesting, but definitely a bit out of my realm at this point.
Old Aug 27, 2014 | 01:11 PM
  #30  
Mech5700's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 476
Total Cats: 13
From: Port Saint Lucie,FL
Default

I like how people relate the spooling of the EFR to magic lol
Old Aug 27, 2014 | 01:17 PM
  #31  
thenuge26's Avatar
Elite Member
iTrader: (2)
 
Joined: Aug 2012
Posts: 3,267
Total Cats: 239
From: Indianapolis
Default

Arthur C Clarke's third law: Any sufficiently advanced technology is indistinguishable from magic.
Old Aug 27, 2014 | 08:03 PM
  #32  
HHammerly's Avatar
Senior Member
iTrader: (3)
 
Joined: Dec 2007
Posts: 838
Total Cats: 63
From: Brownsburg,IN
Default


You will need this past 10 PSI
Attached Thumbnails Is the EFR6258 too much for stock engine?-7f9353fc-9c69-4c7c-b516-8cce6303f704.jpg   Is the EFR6258 too much for stock engine?-4ae69440-cfad-44a8-b137-34030aa79d2a-1217-0000021108cebcc4.jpg  
Old Aug 28, 2014 | 10:53 AM
  #33  
JasonC SBB's Avatar
Elite Member
 
Joined: Jul 2005
Posts: 6,420
Total Cats: 84
Default

Originally Posted by Savington
It will be difficult/impossible to match the EFR here. The trick turbine wheel reduces rotating inertia and lets the wheel spin up fast. There's no way a 2560R car matches the response. A 2554R car might come close, but give up 100whp on the top end.

Originally Posted by Mech5700
Here is some spool data I found on the collective spool data thread:

I want your spool data! - Page 11 - Miata Turbo Forum - Turbo Kitten is watching you test compression.

Post 203 and 218
2500 and 3000 RPM data:

EFR in #203: 6.5 and 12.5 psi <-- this is a 2.0L!
EFR in #208: 4.5 and 10 psi
My 2560 data: 7 and 14 psi.

My 2554 data:
9 psi at 2500 (and 5 psi at 2000)

So GT2560 has better low end than EFR6258 even on a 2.0.
Still a pretty big difference.

Because the 2554 can make more than enough torque to break stock rods, it's a great street turbo for a stock motor. For a built street/track car, I personally like the GTX2863 on paper.
Old Aug 28, 2014 | 11:00 AM
  #34  
18psi's Avatar
VladiTuned
iTrader: (76)
 
Joined: Apr 2008
Posts: 35,821
Total Cats: 3,482
Default

So in your tests the 2560 spools faster than the 2554?

And I think they will next mention transients, "which you can't see on a dyno"
Old Aug 28, 2014 | 11:08 AM
  #35  
Leafy's Avatar
Elite Member
iTrader: (1)
 
Joined: Jun 2012
Posts: 9,491
Total Cats: 105
From: NH
Default

Look as his dad again, 2554 was at 2k and 2.5k the rest were at 2.5k and 3k. Who cares about making boost down there anyways? You've never using that boost.
Old Aug 28, 2014 | 11:12 AM
  #36  
18psi's Avatar
VladiTuned
iTrader: (76)
 
Joined: Apr 2008
Posts: 35,821
Total Cats: 3,482
Default

Originally Posted by Leafy
Look as his dad again, 2554 was at 2k and 2.5k the rest were at 2.5k and 3k. Who cares about making boost down there anyways? You've never using that boost.
That's what I have been preaching for years, and now that I'm DD'ing my car and its all city streets I notice that I'm in 2-3k range pretty much exclusively.
I don't think I or anyone else really needs any more than a couple psi down there and about 150-160tq, but that much alone would make the car amazing at effortless, quiet (more or less) acceleration.

I dunno
Old Aug 28, 2014 | 11:22 AM
  #37  
Leafy's Avatar
Elite Member
iTrader: (1)
 
Joined: Jun 2012
Posts: 9,491
Total Cats: 105
From: NH
Default

The car just isnt geared for that. And if it was it would just result in hitting boost on the highway on a slight grade like the td04 2.5L wrx. I feel like the only one around here that thinks stock power is perfectly adequate for driving on the street. And fun, you get to feel like boy racer reving to 4k just to accelerate with the rest of traffic and no one knows. But yeah the racecar has noticeably more pickup even at 2k rpms once the tarbo went on compared to N/A.
Old Aug 28, 2014 | 11:29 AM
  #38  
18psi's Avatar
VladiTuned
iTrader: (76)
 
Joined: Apr 2008
Posts: 35,821
Total Cats: 3,482
Default

The car is absolutely geared for that. I have literally been driving this way since I got it years ago. 6sp+3.9+45mph streets most the way there, means i'm in the 2500 range almost always if I don't rev it out like a boy racer. And even when I get on the freeway I can shift at 3k and still merge on and if I keep it at 65 (I only take the freeway for 1 exit, or 1 mile) its still close to 3k.

The older I get the more appealing a corvette powerband becomes to me. I loved driving the vette to work - get pushed back in your seat and still only turning 2k rpm, and making no noise.
Old Aug 28, 2014 | 11:32 AM
  #39  
shuiend's Avatar
mkturbo.com
iTrader: (24)
 
Joined: May 2006
Posts: 15,235
Total Cats: 1,700
From: Charleston SC
Default

Originally Posted by 18psi
The car is absolutely geared for that. I have literally been driving this way since I got it years ago. 6sp+3.9+45mph streets most the way there, means i'm in the 2500 range almost always if I don't rev it out like a boy racer. And even when I get on the freeway I can shift at 3k and still merge on and if I keep it at 65 (I only take the freeway for 1 exit, or 1 mile) its still close to 3k.

The older I get the more appealing a corvette powerband becomes to me. I loved driving the vette to work - get pushed back in your seat and still only turning 2k rpm, and making no noise.
I am glad you are seeing the light, I hope you love the 2554 when you get it on.
Old Aug 28, 2014 | 12:06 PM
  #40  
JasonC SBB's Avatar
Elite Member
 
Joined: Jul 2005
Posts: 6,420
Total Cats: 84
Default

EFR6258 and GTX2863 compressor maps awfully similar:

Red is the EFR:

Attached Thumbnails Is the EFR6258 too much for stock engine?-efr6258-gtx2863-overlayed.png  



All times are GMT -4. The time now is 08:16 AM.