General Miata Chat A place to talk about anything Miata

Wastegate signal - anyone tried moving it?

Thread Tools
 
Search this Thread
 
Old 12-17-2006, 03:02 PM
  #1  
Elite Member
Thread Starter
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,537
Total Cats: 42
Default Wastegate signal - anyone tried moving it?

Got the idea from the SRT4 guys, with the SRT it's common practice to move the vacuum tube from the compressor itself to just after the intercooler, so that the turbo will make up for any pressure loss across the core. Any Miata people tried this?
kotomile is offline  
Old 12-17-2006, 03:24 PM
  #2  
AFM Crusader
iTrader: (19)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,667
Total Cats: 337
Default

I run mine off the back of the intake manifold now. Seems much smoother and haven't hit any problems yet.
olderguy is online now  
Old 12-17-2006, 03:26 PM
  #3  
Senior Member
 
Al Hounos's Avatar
 
Join Date: Oct 2005
Location: Knoxville
Posts: 1,168
Total Cats: 0
Default

How does it make any difference? You're setting it by the boost gauge, which is at the manifold, so....
Al Hounos is offline  
Old 12-17-2006, 03:31 PM
  #4  
AFM Crusader
iTrader: (19)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,667
Total Cats: 337
Default

Originally Posted by Al Hounos
How does it make any difference? You're setting it by the boost gauge, which is at the manifold, so....
Haven't proven it out yet, but I think at high boost and high cfm, controlling the setting at the compressor can dump the wastegate at a time where it is not maintaining the pressure at the manifold. I think this is why I lost boost at the dyno in the higher rpm's.
olderguy is online now  
Old 12-17-2006, 03:33 PM
  #5  
Elite Member
Thread Starter
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,537
Total Cats: 42
Default

Originally Posted by Al Hounos
How does it make any difference? You're setting it by the boost gauge, which is at the manifold, so....
Just so I'm clear, I'm talking about the signal to the wastegate actuator from the turbo. On my Greddy the signal tube is about 8" long and comes directly from a fitting on the turbo itself. The idea is to get the signal further downstream to trick the turbo into spooling faster and producing a little more boost.
kotomile is offline  
Old 12-17-2006, 03:51 PM
  #6  
Senior Member
 
Al Hounos's Avatar
 
Join Date: Oct 2005
Location: Knoxville
Posts: 1,168
Total Cats: 0
Default

Yeah, I know what you mean. I guess it might help it spool a little faster since it'll start bleeding the boost off a little later. Never thought of it like that. But it still will only make as much boost as you set it for any loss through the IC is already made up for since you are setting the boost level post IC anyway.
Al Hounos is offline  
Old 12-17-2006, 05:22 PM
  #7  
Senior Member
 
airbrush1's Avatar
 
Join Date: Nov 2005
Location: Baltimore Maryland
Posts: 1,038
Total Cats: 9
Default

it would be almost like a "crack pressure" adjustment on an electronic boost controller...

It delays the wastegate's acquisition of the boost signal..... based on distance rather than duty cycle..... and lets the turbo spool a bit more before the wastegate opens up to regulate the boost.....
airbrush1 is offline  
Old 12-17-2006, 05:24 PM
  #8  
:(
iTrader: (7)
 
magnamx-5's Avatar
 
Join Date: Jul 2006
Location: nowhere
Posts: 8,255
Total Cats: 4
Default

I even ran with no boost signal to my WG talk about delayed WG deployment hit 20 psi that was fun
magnamx-5 is offline  
Old 12-17-2006, 05:35 PM
  #9  
Elite Member
iTrader: (7)
 
samnavy's Avatar
 
Join Date: Apr 2006
Location: VaBch, VA
Posts: 6,451
Total Cats: 322
Default

As I will shortly cover in another post, I just moved my WG source from about 8" of hose (through MBC) directly off the compressor housing to a 5foot piece of hose off the manifold. Still have the exact same overshoot problem. No change whatsoever in response or spool.
samnavy is offline  
Old 12-17-2006, 05:50 PM
  #10  
:(
iTrader: (7)
 
magnamx-5's Avatar
 
Join Date: Jul 2006
Location: nowhere
Posts: 8,255
Total Cats: 4
Default

realy moving the Mbc over to the manifold with a short peice of line helped me.
magnamx-5 is offline  
Old 12-17-2006, 07:42 PM
  #11  
Senior Member
 
Fritch's Avatar
 
Join Date: Mar 2005
Location: Holiday, FL
Posts: 563
Total Cats: 0
Default

mine is run from the intake manifold, works fine
Fritch is offline  
Old 12-17-2006, 08:45 PM
  #12  
Junior Member
iTrader: (8)
 
Stripes's Avatar
 
Join Date: Jun 2005
Location: Lansdale, PA
Posts: 428
Total Cats: 0
Default

I've had great success with the intake manifold. At first, I was running my wastegate signal off the turbo compressor and experienced minor boost spiking. I've tested my wastegate signal in various locations and the intake manifold held the most consistent readings.
Stripes is offline  
Old 12-17-2006, 08:46 PM
  #13  
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,091
Total Cats: 7
Default

I've done both, for the sake of not having as much crap under the hood, I run it off the compressor with no problems.
cjernigan is offline  
Old 12-17-2006, 08:59 PM
  #14  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,494
Total Cats: 4,080
Default

sourcing your gauge off the manifold and you see exactly what the engine sees...just up the boost a tad to make up for pressure loss then.
Braineack is offline  
Old 12-17-2006, 09:28 PM
  #15  
Senior Member
 
bripab007's Avatar
 
Join Date: Dec 2004
Posts: 1,450
Total Cats: -1
Default

MAP sensor for boost controller runs off intake manifold, here.
bripab007 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
StratoBlue1109
Miata parts for sale/trade
21
09-30-2018 01:09 PM
Corky Bell
Prefabbed Turbo Kits
18
11-22-2016 09:01 PM
itsMikey
MSPNP
3
09-28-2015 06:40 AM



Quick Reply: Wastegate signal - anyone tried moving it?



All times are GMT -4. The time now is 10:24 AM.