Ok, I'm beginning to get confused. I'm picking up a kit that is internally wastegated at 6psi and has an fmu. I've been reading all the boost sticky's on "basic" setups and what is needed but I don't see anything about a map sensor. Is this not a necessary item for my 01 LD9 with small boost? Clear up my confusion please.

The map sensor will tell your car's ecm when you're in boost. If you tweak the fuel system with an FMU and AFPR, the ecm won't need to know anything.

You could get the gm reflash since you have an 01.


~Boost. Its what's for dinner!~

Alright, sounds good. Thanks for the info.

What afpr is everyone using? Are there any that have a gauge right on the unit other than those cheap ebay items?

I would get a 2 bar map sensor and then use HP tuners to run a modified gm reflash. Not to mention you can change so many other things with HP tuners. The whole point of a afpr and fmu is to get around limitations of the computer. Why not just use HP tuners to change the computer. Fix the problem at the source. You are lucky enough to have a 2001 and be able to change the computer with HP tuners. I would take advantage of the technology. This was not even an option when those stickys were made, thus why it is not mentioned.

It would stand to reason that the more you increase fuel pressure the more the chance of it leaking fuel somewhere.




Edited 2 time(s). Last edited Tuesday, May 08, 2007 1:23 PM


FORGET GIRLS GONE WILD WE HAVE GOVERNMENT SPENDING GONE WILD!

bah forget the map sensor it can only read up to 5 volts anywayz so it will never go into boost as a result then again i blew a rod out the front of my engine so who am i to talk



"dude, thats a girls car"
PSHHHTTT NOT ANY MORE!!!!!!!

MUFF wrote:bah forget the map sensor it can only read up to 5 volts anywayz so it will never go into boost as a result then again i blew a rod out the front of my engine so who am i to talk

technically true, they wont read over 5V... but...a N/A car runs a 1bar sensor that sees 5V at atmospheric pressure. Where as a 2bar MAP will see 5V at 2X atmoshperic pressure, so the computer can see signal that it is in boost, rather than that it is at atmospheric when its actually in boost

_





Now with northstar V8, IRS, 20's n 22's

Lots of bad info in this thread.

the stock map reads -14.7 to 0 (1.0 bar or atmospheric pressure) on a 0-5V signal

the 2.0 bar map (GM s/c map) reads from -14.7 to 14.7psi (1.0 bar boost) 0-5v signal

if you install the 2.0 bar map sensor (recommended so the PCM call retard timing as you enter boost) you will need to do 2 other things. 1)run larger injectors 2)call gm and get the 2000-2002 GM s/c PCM reflash.

what the reflash does is reprograms the PCM to adjust for the 310cc injectors (stock being 240cc..ish) and ability to read the 2.0bar GM s/c map.


In short, get the GM s/c reflash, 310cc injectors, and a 2.0 bar map (0-5v). and if you want from there you can tune with HPTuners.com (also see tuning section)


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

Thank you for clearing that up ge_forcez22. That was some much needed information. I Appreciate it!

not to dwell on this too much but, stock map actually reads 0PSI to 14.7PSI, boost pressure gauges dont read absolute presure as a MAP sensor does, which throws a lot of people off. vacuum is simply an absence of, or less than the 14.7PSI that is atmospheric pressure. 1BAR is 0-14.7PSI, 2BAR is 29.4PSI absolute pressure. a 2BAR sensor will still read down to 0 PSI, full vacuum putting atmospheric pressure (14.7PSI) at 2.5V and 2BAR at 5V.
it is assumed that people will be getting tuning done and using bigger injectors when they switch sensors so i didnt mention that although i probably should have.

this is the only link i can find at this moment that may help explain, i will try search some more if i get time
http://www.engineeringtoolbox.com/vacuum-converter-d_460.html

ge_forcez22 wrote:Lots of bad info in this thread.

the stock map reads -14.7 to 0 (1.0 bar or atmospheric pressure) on a 0-5V signal

the 2.0 bar map (GM s/c map) reads from -14.7 to 14.7psi (1.0 bar boost) 0-5v signal

if you install the 2.0 bar map sensor (recommended so the PCM call retard timing as you enter boost) you will need to do 2 other things. 1)run larger injectors 2)call gm and get the 2000-2002 GM s/c PCM reflash.

what the reflash does is reprograms the PCM to adjust for the 310cc injectors (stock being 240cc..ish) and ability to read the 2.0bar GM s/c map.


In short, get the GM s/c reflash, 310cc injectors, and a 2.0 bar map (0-5v). and if you want from there you can tune with HPTuners.com (also see tuning section)

_





Now with northstar V8, IRS, 20's n 22's

yah, thats with PSIG and PSIA, but this thread is not at that level yet, I was speaking in the simple terms of, "if you had a boost gauge..."

becuase vacumm is not measured in psi. But good info.


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

Damn ge_force..... I'd expect more comming from you!!! Glad Ztwo4 cleared that up for everyone.

MUFF wrote:bah forget the map sensor it can only read up to 5 volts anywayz so it will never go into boost as a result then again i blew a rod out the front of my engine so who am i to talk

Umm...... and now we know why you blew a rod out of the engine...... ALL GM MAP Sensors are "5 volt" sensors. If you use the correct sensor, with the correct ECM Flash, it will read boost.




SPD RCR Z - '02 Z24 420whp
SLO GOAT - '04 GTO 305whp
W41 BOI - '78 Buick Opel Isuzu W41 Swap

Quote:

Damn ge_force..... I'd expect more comming from you!!! Glad Ztwo4 cleared that up for everyone.

what??? that quote is not from me. I will get into what I was getting at in a little more detail.

PSIA = PSIG + 14.7
PSIG = PSIA - 14.7
In addition, PSIG and PSIA measurements can be converted to inches of mercury and inches of water.
In Hg = PSIG x 2.
In Hg = PSIA x 2
In H2O = PSIG x 27
In H2O = PSIA x 27

Differential pressure is the difference in pressure measurements taken at two related points. It is calculated by subtracting the lower pressure reading from the high pressure reading. Differential pressure may be either absolute or gage pressure, as long as both points are measured in the same units.


I would not assume that just because you change a map sensor you would change injectors. I going from non boosted applications to running some pressure IMO you should increase injector size and run the appropriate MAP sensor be it 2.0 bar (29.4psiA ) which will read 14.7psiG or 3.0 (44.1psiA) which will read 29.4psiG on the boost gauge. When reaching 0psiA on the boost gauge it will read 'vacumm' or negative which is measured in "inches of mercury".

I could have been more technical but the info I gave was correct and very simplified, too simplified? maybe, but now that he understands that lets throw this at him and he has a much better chance of understanding it.

Quote:

the stock map reads -14.7 to 0 (1.0 bar or atmospheric pressure) on a 0-5V signal

the 2.0 bar map (GM s/c map) reads from -14.7 to 14.7psi (1.0 bar boost) 0-5v signal

if you install the 2.0 bar map sensor (recommended so the PCM call retard timing as you enter boost) you will need to do 2 other things. 1)run larger injectors 2)call gm and get the 2000-2002 GM s/c PCM reflash.

what the reflash does is reprograms the PCM to adjust for the 310cc injectors (stock being 240cc..ish) and ability to read the 2.0bar GM s/c map.

I could have said:

Quote:

stock reads 14.7psiA 0-5v
gm s/c map reads 29.4psiA 0-5v
with the Gm s/c reflash and the map/injectors you will have timing retard and added fuel (not tuned amount) for boost.

then I would get comments like "I don't want to run 29 psi boost" or "what is psiA" or "or how am I running boost stock", I stand by what I said, I almost put to the old psi = hp level, but not quite.


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

gotcha! just that you said bad info, which i dont believe it to be. you wouldnt see -14.7PSI on a gauge (or any - PSI for that matter) so i wasnt sure that was what you were getting at. it looks like we are on the same page anyway, and hopefully people can use the extra info.

_





Now with northstar V8, IRS, 20's n 22's

I was refering to muff's post , lol, but it is all good man, just make sure you do a couple things before you boost, and think of some of the others.

research
buy stuff
research
install
research
manage fuel
premium fuel
retard timing
intercool
boost
tune
up boost
tune
water meth
tune

and in that order


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

cant argue with the research thats for sure hopefully the person who posted this originally picks up a couple things out of this, then it would be all good. but as for the original question, it is possible to run boost with a rising rate pressure regulator and bigger injectors but it is not ideal by any means. i am actually running this setup now but it isnt a daily driver (only have maybe 100km on the setup so far) and it is still a pain to drive sometimes cause there isnt nearly enough control, but originally i wasnt even sure if i was going to stay boosted. either way i have hptuners on the way and that is by far the best way to go- with a 2BAR MAP of course

_





Now with northstar V8, IRS, 20's n 22's