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Discussion Starter · #1 ·
I am not getting a whole lot of help here. I need some sort of direction tuning my 30lb injectors for boost. I am running 5 psi.

Its the stock FPR and its not boost referanced. The injectors are Accel 30lb High Impedance from a LT-1.
Fuel pressure (stock) is 60psi (I think). I also have a LC-1 wideband.

Mods are:
t3/t4
-Compressor Specs:
- 3" compressor inlet.
- 2.130" Inducer.
- 2.755" Major.
- 2" Compressor Outlet.
- T04B/T4 Type Compressor Housing.
- Compressor .50 AR
- Compressor 57 Trim
- 6 Blade T4 type compressor wheel.
Turbine Specs :
- T3 Type Turbine flange.
- T3 5 bolt flange.
- Turbine .63 A.R.
- 2.205" Minor and 2.570" Major Propeller.
- T3 Turbine Housing.
- 2.274" Outlet.
- 10 Blade Type Turbine.
Internal wastegate

NGK TR6 plugs (stock are tr5s) so they are + 1 colder.

stock internals but a rebuilt engine with a port and polish



Here are my 2 threads @ hpt forum and Jbody.org

They are telling me its going to be quite difficult.
 

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Unfortunately there isn't much I can help you with, I know nothing about that 4 cylinder. But unlike those assholes on the HPTuners forum I'm not going to tell you you're in over your head. That guy is an ass.

For starters, get a boost referenced Fuel Pressure Regulator if you can. I don't know what your regulator looks like but if its like this:
http://www.ecklers.com/corvette-fue...ine+&+Related+-+Fuel+System+-+ALL-_-35855-_-X

Then you can buy that one. Thats boost referenced.

As far as fuel injectors go, you need this information from a LT1 Camaro in order to set up the injectors correctly.
http://img264.imageshack.us/img264/347/98comp.png

I can't help you there, HPTuners doesn't support LT1 computers so there is nothing in the Tune Repository that I can extract for you.

What you need to do is go on one of the Camaro forums (LS1tech.com, camaroforum.com, or whatever other forums there are) and ask them if they have this information available from whatever program they use to tune their cars.

You may not be able to get all of that information, but the important ones to get are the Offset, Flowrate (you have this value already, 30lbs/hr), and Short Pulse Adder. And hell...if you can't even get that, even with just the Flowrate value the truck should run ok.

Start with this before you start getting into the tuning.

This 4-cyl is the same one thats in the Cavalier I take it? I have no idea what he means by "LD9 2-bar", but HPTuners has a 2-bar Operating System which basically extends your Volumetric Efficiency table for boost. You also need a 2-bar MAP sensor, which comes stock on the Cobalt SS.
 

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i need a paint job
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the tutu has a boost blind operating system, you cant get a 2 bar for it. i havent messed with the tune in my tutu yet but i have read from csxtreme that its fueled by the tps and the map sensor. he would be the guy you need to talk to about tuning with hptuners, thats what he uses on his truck. i think there are a few guys in the 2.2 section that are using hp to tune there turbo setups. i plan on using it when i put the jammer on it, but until then i cant help you out much more unless i take a look more at the tables and read some.
but i would not get a boost referance regulater, basicly and fmu..
and you should have a wideband.
 

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boosted 2.2L
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2,323 Posts
it gets pretty in depth.
in the 4cylinder section they have like a basics thread or somthing.
it shows you how to figure out your new injector constant.
if you are not flex your fuel pressure is lower than 60 and if your fpr has a vacuum port it should also be able to read boost at a 1:1 ratio. you could confirm this with a fuel pressure gauge.
boost tunning is tricky and entirely too much for me to try to explain in a thread.
pm me you contact info and I can hit you up tomorrow.
 

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does your truck have a maf?

normaly i would shut off the ve part of it and tune maf only or at least turn off the ve part above ~1200rpm. no need for the 2 bar.

you dont need a boost refrenced fpr but it might make things slightly easier

tuning maf is somewhat easy.

my comments are based off of various ls1's and a 4.3 s10. i have never seen the tune from a 4 cyl.
 

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Working on aircraft
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Discussion Starter · #6 ·
does your truck have a maf?

normaly i would shut off the ve part of it and tune maf only or at least turn off the ve part above ~1200rpm. no need for the 2 bar.

you dont need a boost refrenced fpr but it might make things slightly easier

tuning maf is somewhat easy.

my comments are based off of various ls1's and a 4.3 s10. i have never seen the tune from a 4 cyl.
No MAF :( CSextreme is gonna call me tomorrow and he is gonna try to explain it to me, I hope I can catch on lol
 

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I think I saw your post on the J-Body forums. Are you aware of the 2.4L twin cam GMPP supercharger kit? When the dealer installed it they reflashed the 2.4L ECU with a speed-density 2 bar tune, since the factory tune was alpha-n (like 2.2 Cavaliers and S10s). Now since the 2.4L ECU is the same as the 2.2 ECU, you can flash the 2.4 tune on to the 2.2 liter. I would assume you can do the same with an S10. I have a modified 2.4 file to work with a 2.2 for my Cavalier. It is tuned for 50 pound injectors, but you can change the constant. The only problem with this is you lose some gauge functions and some dummy lights come on. Also, you have to license your S10 twice with HP Tuners. Once for the stock tune, and once again for changing the VIN on the 2.4 flash and putting it back on your ECU. So it costs 200 dollars to tune instead of 100 dollars.
 

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i need a paint job
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csxtreme has tried that he said it didnt work very well for nim because of the trans is controled by the ecu also... we have 4l60e's in our trucks cavys dont. he mentioned something about hvac controls too.
 

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csxtreme has tried that he said it didnt work very well for nim because of the trans is controled by the ecu also... we have 4l60e's in our trucks cavys dont. he mentioned something about hvac controls too.
Hmm, it sounds like a manual trans swap would almost fix the problem then :)
 

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boosted 2.2L
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it can be done on a manual. I've seen david's logs files from dts and he is using the 2 bar tune.
the battery light will come on with the tune and the hvac thing. but manual controls will solve the hvac and the alt does charge according to the guage.

this is your best bet.
you will need the tune and a 2 bar map.
I have the part number from the gm sc kit but will have to dig it up again unless someone else can post it.
I plan on doing this setup with two computers.
one for truck and trans and one for engine. it will be fun to wire up but with my boost and power level its a must
 

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What are the guys doing over at jbody.org on sunfires and stuff? Should I just get a FMU?
you can run this w/fmu as most will tell you you can't. you need an adj fmu so that you can set the idle afr's then on boost f/p.setting the idle afr's to f/press is like setting injector constant on hpt.try to get a begi if possible.FMU Instructions.pdf (application/pdf Object) .now listen to this if you run boost below 10psi it will work fine,and pe and ve will work like normal without tuning.the ecm will control this as if you tuned it.try starting out adjustment with around 50-55psi at idle with vac line disconnected using a fuel pressure guage.reconnect that will get you idling then adjust WOT.
 

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boosted 2.2L
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I've herd on non flex fuel trucks you will hit the fuel pump's surge level pretty fast and it will bleed the pressure off arround 70 psi or something (not sure exact numbers)
 

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on the grill
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old thread but im going thru this with mine as well. slowly working things out. pinching off the return in my 99 gets 93-95psi at the rail in my truck. with my inline pump on, the injectors slam shut at about 110psi. im tuning mine with the factory injectors, and the factory fpr gutted with an adjustable/referenced 1:1 fpr set at 85 psi (unplugged at idle) instead of going bigger on the nozzles and keeping it at stock pressure. just thought id add that here since it seemed to apply. :)
 

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^ you will likely be beaten with a rubber hose for bringing back an old thread lol. But since im here, i run a fmu 10:1, with stock injectors 24# i think being flex fuel. i set my pe (power enrichment) tables to turn on when my turbo starts spooling, and set the afr at 12:1. this has worked for a year now on 10psi, unfortunately i think it is killing my fuel pump since it will go lean at wot and my injectors only make it to %60 when it goes lean. side effects of a fmu i guess.
 
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