Notices
MEGAsquirt A place to collectively sort out this megasquirt gizmo

how to run dual boost maps

Thread Tools
 
Search this Thread
 
Old May 14, 2008 | 04:57 PM
  #1  
cardriverx's Avatar
Thread Starter
Elite Member
iTrader: (12)
 
Joined: Jan 2007
Posts: 2,573
Total Cats: 12
From: Hermosa Beach, CA
Default how to run dual boost maps

Now I know it uses the JS1 pin, but do I need to ground it to activate the 2ed table? Like a switch going from the JS1-switch-ground wire?
Old May 14, 2008 | 05:04 PM
  #2  
Joe Perez's Avatar
Boost Pope
iTrader: (8)
 
Joined: Sep 2005
Posts: 34,402
Total Cats: 7,523
From: Chicago. (The less-murder part.)
Default

On a 3.0 PCA, it's JS9, which is logically equivalent to pin 6 of JP1 on a R2.2 PCA.

Here:
http://www.msextra.com/manuals/MS_Ex....htm#mapswitch
Old May 14, 2008 | 05:16 PM
  #3  
MikeRiv87's Avatar
Junior Member
iTrader: (12)
 
Joined: Oct 2007
Posts: 487
Total Cats: 1
From: Central, NJ
Default

if your just looking for a low/high switch and ur using an EBC u can always just run a toggle on the signal wire from your ms to the ebc. This will give you a low (gate pressure) and a high which will correspond to the ebc duty table in your ms. Don't make things more complicated than they have to be.
Old May 14, 2008 | 05:25 PM
  #4  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

Originally Posted by MikeRiv87
if your just looking for a low/high switch and ur using an EBC u can always just run a toggle on the signal wire from your ms to the ebc. This will give you a low (gate pressure) and a high which will correspond to the ebc duty table in your ms. Don't make things more complicated than they have to be.
I think this is the best way since I don't like using closed loop boost control.
Old May 14, 2008 | 06:17 PM
  #5  
cardriverx's Avatar
Thread Starter
Elite Member
iTrader: (12)
 
Joined: Jan 2007
Posts: 2,573
Total Cats: 12
From: Hermosa Beach, CA
Default

Originally Posted by MikeRiv87
if your just looking for a low/high switch and ur using an EBC u can always just run a toggle on the signal wire from your ms to the ebc. This will give you a low (gate pressure) and a high which will correspond to the ebc duty table in your ms. Don't make things more complicated than they have to be.

Gate pressure on my car is very low, like 5 psi. I do not wanna run that haha.

Ill have to take a look at the diagrams, thanks joe.
Old May 14, 2008 | 06:35 PM
  #6  
TonyV's Avatar
Elite Member
iTrader: (17)
 
Joined: May 2007
Posts: 1,615
Total Cats: 2
From: NY
Default

I was interested in this as well, but after some driving at 5psi, I can finally see what Scott meant by "your not gonna wanna go back to low boost" lol...

But for ****'s sake, IF one wanted to do the above (wg pressure OR ebc map via toggle switch), wouldnt you have to:

A-tune 2 diff msq's (one for wg boost, one for high boost)
B-have to still find a way to switch between the 2 msq's/maps???

I mean I guess you could just plug in the laptop and load the appropriate table for the correct boost situation, but that kinda defeats the purpose of a "switch"..no?

Or is possible to tune 1 table well enough to handle both high/low boost properly?
Old May 14, 2008 | 06:38 PM
  #7  
Joe Perez's Avatar
Boost Pope
iTrader: (8)
 
Joined: Sep 2005
Posts: 34,402
Total Cats: 7,523
From: Chicago. (The less-murder part.)
Default

Originally Posted by tvalenziano
IIF one wanted to do the above (wg pressure OR ebc map via toggle switch), wouldnt you have to:

A-tune 2 diff msq's (one for wg boost, one for high boost)
B-have to still find a way to switch between the 2 msq's/maps???
A- No, of course not. Think about it- if you push the pedal down part-way and go to 5PSI, then push it all the way and go to 13 PSI, did you need two maps to accomplish that? No. You simply have one map which is tuned for all MAP conditions- from vacuum all the way to max boost, and everything in-between.

B- No, of course not. If you do the switching by using a toggle to interrupt the line to the EBC, then no MS-related fanciness will be necessary. The MS will simply fault out of closed-loop boost when it realizes its not hitting its targets and revert to the DC table, which will of course accomplish nothing since the EBC is disconnected.

Or is possible to tune 1 table well enough to handle both high/low boost properly?
You really don't understand how any of this works, do you?
Old May 14, 2008 | 06:46 PM
  #8  
Savington's Avatar
Former Vendor
iTrader: (31)
 
Joined: Nov 2006
Posts: 15,442
Total Cats: 2,106
From: Sunnyvale, CA
Default

Originally Posted by Joe Perez

You really don't understand how any of this works, do you?

pwnd
Old May 14, 2008 | 07:24 PM
  #9  
TonyV's Avatar
Elite Member
iTrader: (17)
 
Joined: May 2007
Posts: 1,615
Total Cats: 2
From: NY
Default

lol, no but trying to...and think I'm grasping this concept a lil better now...
Old May 14, 2008 | 10:00 PM
  #10  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

You really dont need to tune different fuel maps. it can handle all boost levels, just as it can handle all vacuum conditions.

Since you have TPS you can make your boost map go low boost at 95% throttle and full boost at 100% throttle. That's easy enough.

or you can add a MBC into the wastegate line for your low boost setting. So when you switch the solenoid off, the MBC will keep the boost above 5psi, but below your "high" boost.

You can do dual boost control maps, its an easy mod, however it require closed loop boost maps. when the switch is toggled, you have the option to change to a new fuel map and spark map, none of which you need to do.
Old May 14, 2008 | 10:07 PM
  #11  
kotomile's Avatar
Elite Member
iTrader: (24)
 
Joined: Oct 2006
Posts: 7,537
Total Cats: 42
From: Monterey, CA
Default

shorten the WG arm and the 'EBC off' psi won't be 5 psi anymore

simple.
Old May 14, 2008 | 10:15 PM
  #12  
ZX-Tex's Avatar
Elite Member
iTrader: (15)
 
Joined: Dec 2007
Posts: 4,847
Total Cats: 27
From: San Antonio, Texas
Default

Originally Posted by kotomile
shorten the WG arm and the 'EBC off' psi won't be 5 psi anymore

simple.
Yep. I did this with a GT2560 and it works great. I went from 5 psi to 7.5 psi just by tightening the arm.

FWIW after the intercooler and clutch install I will be raising the boost and doing it with the method described by MikRiv. Use the wastegate for low boost, use the MS and EBC for high boost, switch the signal to the EBC to change modes.
Old May 14, 2008 | 10:56 PM
  #13  
cardriverx's Avatar
Thread Starter
Elite Member
iTrader: (12)
 
Joined: Jan 2007
Posts: 2,573
Total Cats: 12
From: Hermosa Beach, CA
Default

Guys, I still want the use of the EBC at both the low and high boost.

Now would a active low input work? The way I see is that I need a 5v source, splice that into the line that goes to one side of the switch and js9 using 2 diodes, Then the other end of the switch goes to a ground.

Is that right?

Im just going to use the MS's abilty to switch between 2 EBC maps.

Also, has anyone found the closed loop system to work ok, since I have to use it?
Old May 15, 2008 | 12:17 AM
  #14  
Joe Perez's Avatar
Boost Pope
iTrader: (8)
 
Joined: Sep 2005
Posts: 34,402
Total Cats: 7,523
From: Chicago. (The less-murder part.)
Default

Originally Posted by cardriverx
Now would a active low input work?
Again: http://www.msextra.com/manuals/MS_Ex....htm#mapswitch

Note that there are two different circuits, one for active-high, one for active-low.
Old May 15, 2008 | 07:36 AM
  #15  
cardriverx's Avatar
Thread Starter
Elite Member
iTrader: (12)
 
Joined: Jan 2007
Posts: 2,573
Total Cats: 12
From: Hermosa Beach, CA
Default

Originally Posted by Joe Perez
Again: http://www.msextra.com/manuals/MS_Ex....htm#mapswitch

Note that there are two different circuits, one for active-high, one for active-low.
Could you explain the differences for me?
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
FrankB
Miata parts for sale/trade
6
Sep 30, 2015 11:48 AM
brandonbkd
MEGAsquirt
0
Sep 28, 2015 11:52 PM
viriiguy
General Miata Chat
5
Sep 28, 2015 07:39 PM




All times are GMT -4. The time now is 08:17 PM.