GTP Map Sensor Questions

[Missing2]

OK, I have been doing a little research and looked at a GTP tune..

there are 3 gm map sensors 1, 2, and 3 bar..

I belive gtp's have 2 bar sensors?? 3 maybe??
(hopfuly a gtp person will chime in here)

It will be no problem to upgrade to a 2 or 3 bar sensor.. they are all 3 wire setups and they use the same voltage range as a 1 bar..

however you will need to tune for it.. essentaly the difference is the slope of the voltage, they are all pretty much linear just different slopes..

At this point I would love to upgrade to a 2 bar becuase that will be mor ethen enough for my appication.. however it am a little worred about tuning..

on my supercharged car would it be safe to just use the gtp's??

I am also assuming that the the map sensor only really effects the primary VE table? so that would be the only one that needs editing.. is that table even used at wot?

I have head a few rumors on here and on camarov6 that hptuners was planning on adding this as a feature.. but it has only been rumors?? whats the verdict guys?

lets hear some insight/opinions..

here are some links for some info on gm map sensors
http://www.robietherobot.com/storm/mapsensor.htm

http://hhscott.com/93tmv/3-bar_map.htm

and btw the sensors are only about $50 form gmparts direct..

[Chris@HPTuners]

the v6 code uses a 2 bar map for s/c apps.

installing a 3bar is not simple and requires quite a few mods to make it actually work (and likely a dumping of the MAF sensor.)

Why do you want a 3bar MAP? Are you maxing the MAF freq or something?

[Missing2]

the v6 code uses a 2 bar map for s/c apps.

installing a 3bar is not simple and requires quite a few mods to make it actually work (and likely a dumping of the MAF sensor.)

Why do you want a 3bar MAP? Are you maxing the MAF freq or something?

I will be soon..

[johnt]

Guys, help me out here. How does using a bigger MAP sensor (with its prerequisite changes) help if you're maxing your MAFF?

John

[load97]

I'd like to know too

[Chris@HPTuners]

it doesn't unless you are running speed density mode, with the approporiate hacks to actually use it.

[WhiteHawk]

Guys, help me out here. How does using a bigger MAP sensor (with its prerequisite changes) help if you're maxing your MAFF?

John

I am not sure how much it would help unless you used a convertor box to scale it back to match the 2 bar output. Then you could rescale your Ve tables and run a 3 bar tune in speed density mode. IT's an awful lot of work for a small gain IMHO.

One of the big benefits, though, is that you have a built in 29 psi boost gauge, where you only go about 15 with the stocker.

-Geoff

[Missing2]

ok.. I am pretty sure i dont need one.. I was tuning for a while today..

i am maxing out the existing map sensor at wot.. but the MAF seems fine for the most part.. and i am not maxing out air volume per cylender or anything either in the histograms..

it getting there but not yet.. i would iamgine when i start running 7-9 lbs this may become an issue.. but i am OK for now..

[Chris@HPTuners]

do you have a 2bar MAP fitted? 2bar is 15 PSI boost, 3bar is 30 PSI.

I can tell you if are maxing out a 2 bar MAP at high RPM WOT then you are likely easily maxing out just about every table in the PCM.

[Missing2]

do you have a 2bar MAP fitted? 2bar is 15 PSI boost, 3bar is 30 PSI.

I can tell you if are maxing out a 2 bar MAP at high RPM WOT then you are likely easily maxing out just about every table in the PCM.

nah.. i have a single bar.. its a v6 camaro.. they come NA so.. obviously the single bar is fine..

but with the blower i wanted to step up to a 2..

see what i am saying?
what is involved in doing that..

[Quick6]

do you have a 2bar MAP fitted? 2bar is 15 PSI boost, 3bar is 30 PSI.

I can tell you if are maxing out a 2 bar MAP at high RPM WOT then you are likely easily maxing out just about every table in the PCM.

Actually , the stock map maxes out at 14.35psi. I do it every time i nail it! I'm pulling about 15psi boost and my maff table is hitting about 9800Hz. I also run 42lb injectors which i've scaled in also. My combo is very mild so i highly doubt i'm maxing all the tables. I do wonder what effect maxing the map is doing to my cals?? My 02's stay around 940 so all is good for now.

[johnt]

Actually , the stock map maxes out at 14.35psi. I do it every time i nail it! I'm pulling about 15psi boost and my maff table is hitting about 9800Hz. I also run 42lb injectors which i've scaled in also. My combo is very mild so i highly doubt i'm maxing all the tables. I do wonder what effect maxing the map is doing to my cals?? My 02's stay around 940 so all is good for now.

Hey What's up Rob?

Well, my setup is a little less mild than yours and I'm maxing a few calibrations myself. Currently I'm seeing 18 psi of boost, and I expect the manifold pressure to increase a little more once I turn the juice on. I'm also scaling the MAF down to keep that from running off the end of the table. I was doing some tuning yesterday and noticed that I exceed the highest g/cyl value in the spark tables by the time I was at 40% TPS and 3000 RPM. Who knows what else I'm maxing.

It appears that our PCMs are fairly intelligent and do a good job at extrapolating and keeping things from getting too ugly when we go past the table limits. But there is no doubt though that we're not running optimally. I don't have an answer.

John