I know at least a handfull of you guys are over 14psi... So i am just curious as to how you deal with the map pressure above 2 bar.
I know HPT and the GMPP SC reflash lets you run a 2 bar MAP just fine up to 14psi... but when you break that barrier, how do you deal with it?
I am told that going to a 3bar map will kill drivability and you will be lucky to even get it to run, let alone run well.
So what other options are there? Shifted told me that you would likely need to run some sort of fueling system to provide proper fuel above 14psi. and just use HPT for everything in range of the 2bar MAP.
I am not one to doubt shifted at all, but i could have sworn i have read about guys running lots of boost without any crazy setups.
So if you are over 14psi, please let me know how you are dealing with the MAP, and fueling over 14psi.
um... ok... how do you get over 14psi with a 1bar map??
I think what he may mean is you need to ditch the GMSC reflash and tune it via good ole alpha-n. In fact I believe thats how most are doing it. See airtronics and K.Vega.
Good luck
He has a LD9. I believe that most ppl just make the last cell on the fuel map really high and it adds more fuel. The last cell value repeats is what i am hearing. You may be able to use the ve offset as well. I am not a hpt genius though...
Your choice. Fake the 3 bar, max out the top most cell and pray, or find an external way to keep adding fuel and pulling spark with boost.
The biggest question is - how far past 14 psi do you need to / plan to go.
A few psi you can get away with... like 16-17. (with hpt) After that you're asking a lot without finding a proper solution.
I took a 1 bar tune up to 21 psi. Lots of fuel but no timing control so now I've made a fake 2 bar program. I'll do the same with a 3 bar when the time comes.
-Chris-
-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
Well i really have no idea... this is rather unchartered territory here. I am running a 2.7" pulley on the SC (i consider that scaled down) and have my wastegate set to minimal boost. And i am still at 10Psi. I am showing 5psi the the TB and jumps to 10Psi after the blower.
I would really like to bump the turbo up to something more comfortable for it, i didnt pick this turbo to run at 5psi. I had closer to 18 in mind (not realizing 2bar stopped at 14)
well if the sc turns 5psi into 10... then it will likely turn 7psi into 14. so even a lil bump on the wastegate will smack me into the 2 bar limit. So i really would like to try and find its potential and settle on a "sweet spot" but i was really hoping for like low 20's for street use. I didnt put in 8.5:1 compression pistons to stroll along at 10psi.
So i would very much like to get her running in the high teens on pump gas. So it sounds like i will either need a fake 3bar, or stick with the 2bar, and figure out another way to add fuel and controll timing above 14.
Is there any way to use the outputs of HPT pro to control additional fueling? like say control a relay that feeds a fuel solenoid which feeds a nitrous type fuel nozzle to provide added fuel when the psi reaches a certain point?
What is the "proper way" to add fuel and timing in situations like this?
Proper way is a standalone EMS to be honest... but who has that kinda coin and the time to wire it and learn it and get it all working. Way more work and cash.
Don't expect to hit the high teens in boost on pump gas with that blower heating up the air the way it does... not without pulling significant timing. I assume you'll spray alcohol on top of that to help but jeeze at 8.5:1 you'll be pushing it. You might want to run a tad richer than usual... I hope you have an EGT gauge.
You could get an extra injector controller to come on at say 15 psi onward and put a moderately small injector in there... but then you're firing fuel thru the charger and I'm not as versed on taht piece of equipment so I don't know how good of an idea that is.
To me the concern isn't fuel. You can use an FMU if you need, or raise the top cell and be over-rich for a moment at a lower PSI...
The concern is spark retard... esp with that blower heating the air up like a blast furnace.
-Chris-
-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
ken soggs wrote:
What is the "proper way" to add fuel and timing in situations like this?
The "proper" way would be get a standalone... Since I doubt you are going to go that route, just listen to the rest of us and leave the SC reflash on, use the last cells and tune your AFR to where its safe. I have tuned quite a few of these upto 20psi (including Fetters) and had no issues what so ever. I think I read you were using Meth, so that will help out quite a bit with the excess heat you will have with the SC and allow you to run some good timing....
P&P Tuning
420.5whp / 359.8wtq
You would all be amazed at how cool the SC runs when it doesnt have to suck. blowing pressurized air into the blower really seems to help it along. My IAT's have been really reasonable even before meth. I used to hit 150+ all the time and not even pushing it... now even going thru the turbo and blower, i rarely see temps above 130. and that is usually only after sitting at a traffic light.
I really dont think SC heat is going to be nearly as big an issue as it is for the guys who are SC only.
Get some meth spraying, or an intercooler sprayer, and i think i will be looking at temps close to ambient.
at 10psi i am seeing almost no KR under normal conditions... even at 100+ IAT's and a restrictive bumper over my FMIC. So i really think i have some wiggle room here.
I just need to figure out the tuning portion of it.
SweetnessGT wrote:
The concern is spark retard... esp with that blower heating the air up like a blast furnace.
-Chris-
Bet at the '07 bash i had lower intake air temps then you
Why not scale a 3 bar in to the ECM?
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
Taetsch Z-24 wrote:
Why not scale a 3 bar in to the ECM?
Chris
I am getting mixed signals on the 3bar scaling "fake"
Some people tell me it works great, but some people tell me i will be lucky to have it even run with a 3 bar.
(and some of those who say it is a bad idea are very reputable tuners aka shifted)
But if i can get confirmation that it works, and works decently, that would surely be the way to go.
ken soggs wrote:Taetsch Z-24 wrote:
Why not scale a 3 bar in to the ECM?
Chris
I am getting mixed signals on the 3bar scaling "fake"
Some people tell me it works great, but some people tell me i will be lucky to have it even run with a 3 bar.
(and some of those who say it is a bad idea are very reputable tuners aka shifted)
But if i can get confirmation that it works, and works decently, that would surely be the way to go.
I am with Ron (Shifted)... I think too much resolution is lost to make it worth while...
P&P Tuning
420.5whp / 359.8wtq
Well, just thinking out loud here.....
It sounds like the 3bar would work well for high power, mostly boosted applications... but not such a great idea on street and DD purposes....
Well... a tune is only a 60 second flash away... and a map sensor is nothing but a couple wires and a vacuum line...
Couldnt you run 2 sensors? and 2 tunes? one for the strip and 3bar... and one for the street with 2bar.
a quick flash, and swap the map harness, and your now tuned for your particular need... An adjustable boost controller would also compliment this setup well...
a little outside the box... but hell, that isnt exactly anything new for me,
If Ron says no go... NO GO.
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
..... Ask him about using the "SS" 2.5 bar map.......
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
heres my thought, i run 20psi on my car with 14 degrees of timing on pump gas, and honestly im past what hpt can properly handle im just in a halfass it gets the job done phase, if you want to tune your motor to its full potential your going to need a standalone ems of some sorts. now if you plan to run that much pressure with hpt to help out you could add a begi fmu to help adjust the fuel easier, but timing your just limited as far as boost pressure above the 14.7 mark. but by what your saying is your car twin charged??
R.I.P. Brian Klocke, you will never be forgotten
Boosted2point4 wrote:heres my thought, i run 20psi on my car with 14 degrees of timing on pump gas, and honestly im past what hpt can properly handle im just in a halfass it gets the job done phase, if you want to tune your motor to its full potential your going to need a standalone ems of some sorts. now if you plan to run that much pressure with hpt to help out you could add a begi fmu to help adjust the fuel easier, but timing your just limited as far as boost pressure above the 14.7 mark. but by what your saying is your car twin charged??
yep, she sure is...
still breaking the engine in, and trying to get some tuning on her...
The resolution for timing and fuel are @!#$ty to begin with. Scaling it even as a two bar fake is crap. However you can get away doing that for WOT tunes but for good all around driveability forget it........... with HPT the J ECU resolution is just not very good from the get go so without going to a standalone it will not be perfect.
ASE Master Certified Automotive Technician
actually my driveablity isnt horible for having 1000cc injectors, its not perfect but with hpt there is no perfect for our cars, my next tuning system will have a barametric sensor in it too, with the weather change my car has fattened up, yesturday i blew a fireball at a shelby gt 500
he was like 80 and didnt want any...lol
R.I.P. Brian Klocke, you will never be forgotten
oh it was from a roll, 4th gear burn out
shift to 5th kaaaapaawww look back and see what look like where a chipped diesel blew out alot of black smoke.....
R.I.P. Brian Klocke, you will never be forgotten
See! That's my point, my charger temps were 10* BELOW the outside air temps!
OH YA!
Fire balls RULE, when ever i sprayed 50/50 water/meth, every shift felt like a M67 Frag Grenade want off under my car.
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
all that money and effort into the engine with a mickey mouse ecu.
I thought it would be well know by now that modifying any jbody, you'll very quickly outgrow the ecu's capability.
I would def use MS for the fuel portion.. you have two sources of boost, and alpha-n was mentioned as a way to tune in this thread?
You need something that can calculate for load (like the GM s/c reflash you already have) but since you want greater than 2 bar while maintaining drivability, go with MS.
you can leave the spark portion up to the factory ecu for now.. just add an MSD box later for boost related retard if you want it, but get MS to run your fuel at least.
AHH
GM=ECM\PCM and some times VCM....
Honda\Mitus\Dodge = ECU!!!!!!!!!!!
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
Do it at a roll in a 2-3 shift at 7500 rpm... it's like getting kicked in the ass at full speed.