Boost pressure


B O N Y

MODERATOR & FGT OWNER
Mark IV Lifetime
Sep 5, 2005
12,110
Fresno, Ca.
... with the whipples coming out and being optimized,
there soon will be a subline somewhere popping up
saying: 'odometer pegging'...:biggrin

and the speedo and the tach:cheers :thumbsup :cheers
 

SLF360

GT Owner
Mark IV Lifetime
and the speedo and the tach:cheers :thumbsup :cheers

Bony,
of course you are right. I meant the speedo of course...:rofl

PS: you Lacy gif link doesn't work...:confused
 

w. mitty

GT Owner
Mark IV Lifetime
Sep 1, 2005
704
DSC_0108.JPG


Here's a picture of the Mafia unit installed by Whipple:
 
Aug 25, 2006
4,436
Interesting because this was an issue that I brought up prior to purchasing the Whipple. I was told that the vacuum and the boost would register fine within the designed range of the gauge however that it would peg under extreme boost situations with no secondary problems caused. Now if I understand correctly that the gauge is not actually measuring boost but rather a voltage signal produced as the result of likely load etc. I now understand that the gauge readings are likely "interesting" at best once increased boost by any means is introduced to the gals.

Whether as the result of the smaller pulleys and the larger Whipples being installed I think the idea of a plug in ??? to recalibrate the OEM gauge within the depicted range is something that needs to put on the Christmas list.

Certainly during those times when in excess of 15psi it will simply peg or ???? however at least a viable vacuum and boost reading will remain during the greatest percentage of one's drive time.

I for one have no interest in running a vacuum line through the gal nor do I want to swap the gauges out.

I would think that a voltage scaler in the same fashion as the MAFia could be put in line and then tweaked accordly. I share a tweakable device because based on the pulley and or whether a Whipple is installed the voltage would have to be scaled accordingly.

It is on my Christmas list

Just my two cents on this issue.

Shadowman
 

B O N Y

MODERATOR & FGT OWNER
Mark IV Lifetime
Sep 5, 2005
12,110
Fresno, Ca.
Interesting because this was an issue that I brought up prior to purchasing the Whipple. I was told that the vacuum and the boost would register fine within the designed range of the gauge however that it would peg under extreme boost situations with no secondary problems caused. Now if I understand correctly that the gauge is not actually measuring boost but rather a voltage signal produced as the result of likely load etc. I now understand that the gauge readings are likely "interesting" at best once increased boost by any means is introduced to the gals.

Whether as the result of the smaller pulleys and the larger Whipples being installed I think the idea of a plug in ??? to recalibrate the OEM gauge within the depicted range is something that needs to put on the Christmas list.

Certainly during those times when in excess of 15psi it will simply peg or ???? however at least a viable vacuum and boost reading will remain during the greatest percentage of one's drive time.

I for one have no interest in running a vacuum line through the gal nor do I want to swap the gauges out.

I would think that a voltage scaler in the same fashion as the MAFia could be put in line and then tweaked accordly. I share a tweakable device because based on the pulley and or whether a Whipple is installed the voltage would have to be scaled accordingly.

It is on my Christmas list

Just my two cents on this issue.

Shadowman


YES SIR!! Santa, I want one as well, even though I have been a very bad boy this year:willy
 

BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
I posted earlier that the signal to the boost gauge is labeled PWM. Which usually means Pulse, Width Modulation. A fancy term for for changing the duty cycle of a square wave signal to denote boost. A simple voltage scaler won't work. One has to build a box that reads the original PWM signal scales it and output a new PWM signal to the gauge. Not difficult to do in theory, but time consuming and expensive for the limited number of these things one can sell.

I think it would be simply thing for Analogdesigner to build, maybe we should take could of how many people are interested and est. pricing necessary to make it worthwhile for Jay to build them. Similar to the nice Sub/Mac system that Ash came up with.

Someone else posted the Bob Ida has a fix for this. I don't know what his solution is, but it could be as simple as knowing how to reflash the ECU. This should be investigated first.


I don't know how you guys with a Whipple have time to look at the gauge while under full boost, you have to keep your eyes on the road!


BlackICE
 
Aug 25, 2006
4,436
I posted earlier that the signal to the boost gauge is labeled PWM. Which usually means Pulse, Width Modulation. A fancy term for for changing the duty cycle of a square wave signal to denote boost. A simple voltage scaler won't work. One has to build a box that reads the original PWM signal scales it and output a new PWM signal to the gauge. Not difficult to do in theory, but time consuming and expensive for the limited number of these things one can sell.

I think it would be simply thing for Analogdesigner to build, maybe we should take could of how many people are interested and est. pricing necessary to make it worthwhile for Jay to build them. Similar to the nice Sub/Mac system that Ash came up with.

Someone else posted the Bob Ida has a fix for this. I don't know what his solution is, but it could be as simple as knowing how to reflash the ECU. This should be investigated first.


I don't know how you guys with a Whipple have time to look at the gauge while under full boost, you have to keep your eyes on the road!


BlackICE

I too was told the conversion process to build a "black box" is not that big a deal however I too was also told that within the PCM a tweak should be able to be made.

Now as for having the ability to look at the gauge while under full boost; this is doubtful and yet during normal driving it would be a "GREAT" thing.

Shadowman
 

lthlvpr

GT Owner
Mar 8, 2006
299
All-
It is a heck of a lot easier and less costly just to purchase a mechanical boost gauge, put it in a number of locations (including stock swap) so you can see it, and hook it up. It will take about an hour to complete the project and then you can have a boost gauge that goes to 20 or 25 psi for more accurate and reliable boost readings.
 

SLF360

GT Owner
Mark IV Lifetime
its the mafia!

DSC_0108.JPG


Here's a picture of the Mafia unit installed by Whipple:

Guys
I checked. I reloaded the previous tune, mafia setting at 1 and ran the autobahn at 180 miles , back at full 15PSI. The other tune requires the mafia at position 2, and then the gauge showed half the boost. So its only a reding issue, nothing technicalm

What a relief....
Interestin thread. Let's hear it from the whipples what they read at full load !
 

B O N Y

MODERATOR & FGT OWNER
Mark IV Lifetime
Sep 5, 2005
12,110
Fresno, Ca.
Guys
I checked. I reloaded the previous tune, mafia setting at 1 and ran the autobahn at 180 miles , back at full 15PSI. The other tune requires the mafia at position 2, and then the gauge showed half the boost. So its only a reding issue, nothing technicalm

What a relief....
Interestin thread. Let's hear it from the whipples what they read at full load !

AT WOT the guage is pegged. I need a corrected guage.
 

w. mitty

GT Owner
Mark IV Lifetime
Sep 1, 2005
704
My Mafia is at level 2, full boost reads 8 pounds at WOT. Pulley is for 17 pounds. Elevation, 4200 ft. That means the guage is reading about half of the actual number. I'm sure not down on ACTUAL boost, as confirmed by my rear-o-meter.
 
Aug 25, 2006
4,436
My Mafia is at level 2, full boost reads 8 pounds at WOT. Pulley is for 17 pounds. Elevation, 4200 ft. That means the guage is reading about half of the actual number. I'm sure not down on ACTUAL boost, as confirmed by my rear-o-meter.

It probably should not and yet this thread bothers me because having the gauges work properly is a bit more than novel ...... it is what I would expect at the end of the day.

Since the MAFia once placed into postion two it seems to cause the boost gauge to drop in half (this would be easy to confirm) then my original comments remain. I too would like to know what Dustin aka Whipple feels should be done to address this or if infact Bob at IDA has a work around then by all means please confirm this. If a value is associated with the information then please PM me and I will gladly pay the piper.

At this time I have the Whipple soon to arrive and I would like to get my proverbial ducks in a row.

Thank you

Regards

Shadowman
 

MAD IN NC

Proud Owner/ BOD blah bla
Mark IV Lifetime
Feb 14, 2006
4,219
North Carolina
They say SCT is going to come out with a MAF tuned for the GT! The Mafia while works, is a product from Diablo that I bought tuners from before that never met my needs. Hopefully SCT will step up!
 
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SLF360

GT Owner
Mark IV Lifetime
Since the MAFia once placed into postion two it seems to cause the boost gauge to drop in half (this would be easy to confirm) then my original comments remain.

Shadow,

this is correctly what I noted, and also in line with what Walter Mitty observes.
Actually, no issue. Just double what you read, and you are good. On the other hand, more impressive for the passenger, when the dial runs all the way until tilt position at 15... :biggrin

Stefan


PS: I wanna ride Bony's car...:banana
 

B O N Y

MODERATOR & FGT OWNER
Mark IV Lifetime
Sep 5, 2005
12,110
Fresno, Ca.
PS: I wanna ride Bony's car...:banana

Bull, I want a ride in my car with you driving....
My spies tell me you are the master...
Need a Stefan driving lesson!!:cheers :banana :cheers