Miata Turbo Forum - Boost cars, acquire cats.

Prefabbed Turbo Kits A place to discuss prefabricated turbo kits on the market

Car won't hold boost for crap!

Thread Tools
 
Search this Thread
 
Old 11-16-2009, 07:45 AM
  #1  
Senior Member
Thread Starter
iTrader: (3)
 
miataspeed2005's Avatar
 
Join Date: Jul 2005
Location: Connect-I-Cut
Posts: 1,404
Total Cats: 0
Default Car won't hold boost for crap!
If this has been asked before and you know which thread it is feel free to direct me.
Ok so my turbo won't hold boost for ****! As soon as I go on boost it spikes to like 16psi then it goes down to 14psi where it should be and by 6k it's down at like 12psi. It really pisses me off cause I'm loosing 10-15 hp at top and my torque drops like a bitch. If you saw my dyno graph it also didn't help that I was going rich at 6k. Soooo what can I do to fix this?
miataspeed2005 is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-16-2009, 08:42 AM
  #2  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default
stock greddy wastegate right? look to replace the actuator or run some helper springs.
Braineack is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-16-2009, 08:59 AM
  #3  
Cpt. Slow
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,181
Total Cats: 1,132
Default
Yes indeedy, my boost needle was all over the place until I replaced the greddy actuator. You'll probably end up with boost creep though. (positive)
curly is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-16-2009, 09:16 AM
  #4  
Elite Member
iTrader: (5)
 
m2cupcar's Avatar
 
Join Date: Jan 2005
Location: Atlanta
Posts: 7,486
Total Cats: 372
Default
Yep- most IWG actuators start to flake out around double the rating in a boost controlled environment. BTDT. Logging a run with the wg wire shut does wonders for trouble shooting. Just make sure you've got your boost cut where it needs to be for the run.
m2cupcar is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-16-2009, 10:14 AM
  #5  
Senior Member
Thread Starter
iTrader: (3)
 
miataspeed2005's Avatar
 
Join Date: Jul 2005
Location: Connect-I-Cut
Posts: 1,404
Total Cats: 0
Default
Which wastegate do you guys recomend?
miataspeed2005 is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-16-2009, 10:54 AM
  #6  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default
https://www.miataturbo.net/forum/t13351/
Braineack is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-16-2009, 07:10 PM
  #7  
Elite Member
iTrader: (13)
 
Fireindc's Avatar
 
Join Date: Dec 2006
Location: Taos, New mexico
Posts: 6,603
Total Cats: 564
Default
Where are you getting your signal for your wastegate from?
Fireindc is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-16-2009, 09:01 PM
  #8  
Junior Member
iTrader: (2)
 
db84drteg's Avatar
 
Join Date: Dec 2004
Posts: 201
Total Cats: 1
Default
I replaced my wastegate actuator with one from a new GT2871 and I got boost faster and held MUCH better than the Greddy unit.
db84drteg is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-16-2009, 09:10 PM
  #9  
Senior Member
Thread Starter
iTrader: (3)
 
miataspeed2005's Avatar
 
Join Date: Jul 2005
Location: Connect-I-Cut
Posts: 1,404
Total Cats: 0
Default
Originally Posted by Fireindc
Where are you getting your signal for your wastegate from?
Compressor
miataspeed2005 is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-16-2009, 11:05 PM
  #10  
Elite Member
iTrader: (13)
 
Fireindc's Avatar
 
Join Date: Dec 2006
Location: Taos, New mexico
Posts: 6,603
Total Cats: 564
Default
Originally Posted by miataspeed2005
Compressor
Then check out this thread my friend.

https://www.miataturbo.net/forum/t32479/

Should at least help the issue.. if not resolve it altogether.
Fireindc is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 01:25 AM
  #11  
Elite Member
iTrader: (2)
 
triple88a's Avatar
 
Join Date: Apr 2006
Location: Chicago, IL
Posts: 10,454
Total Cats: 1,799
Default
Originally Posted by curly
You'll probably end up with boost creep though. (positive)
If hes not getting boost creep now that means hes got plenty of flow bypassing the turbine so he wouldnt later.

What he has is boost spiking.


Here is where the WG is tied to.. (the line in the background is an oil line and doesnt connect to the wastegate in any way..)
DSCF0043.jpg
triple88a is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 08:05 AM
  #12  
Senior Member
Thread Starter
iTrader: (3)
 
miataspeed2005's Avatar
 
Join Date: Jul 2005
Location: Connect-I-Cut
Posts: 1,404
Total Cats: 0
Default
Originally Posted by Fireindc
Then check out this thread my friend.

https://www.miataturbo.net/forum/t32479/

Should at least help the issue.. if not resolve it altogether.
Why is that not a sticky? That is awesome information, I'm going to try that and upgrade my wastegate. Tune my fuel towards redline a little and hit a dyno again should make a 10-15 hp difference
miataspeed2005 is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 09:16 AM
  #13  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default
Originally Posted by miataspeed2005
Why is that not a sticky? That is awesome information, I'm going to try that and upgrade my wastegate. Tune my fuel towards redline a little and hit a dyno again should make a 10-15 hp difference
shoulda looked at how mine is plumbed when you had the chance...



The nipple just before the TB feeds the wastegate actuator. My boost is so steady you can rest your drink on it.
Braineack is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 09:26 AM
  #14  
Senior Member
Thread Starter
iTrader: (3)
 
miataspeed2005's Avatar
 
Join Date: Jul 2005
Location: Connect-I-Cut
Posts: 1,404
Total Cats: 0
Default
Originally Posted by Braineack
shoulda looked at how mine is plumbed when you had the chance...
You shoulda looked at mine and helped a ***** out when I was complaining about my boost drop at the dyno
miataspeed2005 is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 09:47 AM
  #15  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default
hahah. or that. I was just trying to find someone for you that knew anything about the DINK ecu.
Braineack is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 06:23 PM
  #16  
Elite Member
iTrader: (2)
 
triple88a's Avatar
 
Join Date: Apr 2006
Location: Chicago, IL
Posts: 10,454
Total Cats: 1,799
Default
Isnt your BOV open at idle/vacuum sir?

Originally Posted by Braineack
shoulda looked at how mine is plumbed when you had the chance...

triple88a is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 06:32 PM
  #17  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default
a little crack...why?
Braineack is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 06:41 PM
  #18  
Elite Member
iTrader: (2)
 
triple88a's Avatar
 
Join Date: Apr 2006
Location: Chicago, IL
Posts: 10,454
Total Cats: 1,799
Default
Just curious since its still an unfiltered gap
triple88a is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 07:17 PM
  #19  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default
I don't care about things like that.
Braineack is offline  
Reply
Leave a poscat 0 Leave a negcat
Old 11-17-2009, 07:40 PM
  #20  
Junior Member
 
mafoose's Avatar
 
Join Date: Aug 2009
Posts: 55
Total Cats: 0
Default
Originally Posted by triple88a
Just curious since its still an unfiltered gap
Does air even get sucked into it? I'm pretty sure the airflow is always out the BOV never in.
mafoose is offline  
Reply
Leave a poscat 0 Leave a negcat



Advanced Search
Quick Reply: Car won't hold boost for crap!


Reply Closed Thread Share

All times are GMT -4. The time now is 05:21 AM.