tuning program qestion?

[firestorm13666]

what is the best tuning program out there to program the stock pcm?

[Mars]

gmpcm

[SappySE107]

tunerpro works well too. Its also free. I use GMPCM, Winbin, and Tunerpro depending on the application.

[firestorm13666]

could you give me some information on what you ment by"depending on the application" and thanks for your help.

[SappySE107]

I use winbin for 2.8 and 3.1, gmpcm for the 91-93 DOHC and tunerpro for 94-95 DOHC.

[93gtpdohc]

what about a 93 dohc running on a 90 3.1 TGP bin?
i'm useing tunercat, but haveing problems with excive rev'n sometimes during coasting and idleing, and i can;t seem to be able to cal the right BPC constant for the #36 injectors

[TurboGTU]

Firestone...I would look for the most compleat code mask for your cars chip that has the things you want to change. Then decide which program has it. You'd also want to find a compleate ALDL program for your car also...no sense in modding if you don't know if it ain't working.

i can;t seem to be able to cal the right BPC constant for the #36 injectors

Are these Aftermaket Accels/holly for GM cars..and such..or are they other aftermaket makes. Are they Multec II injectors? Are you running rich every where..even at idle? Have you moded your other tables that directly affect the base pulse like Base Pulse Const. vs Desired EGR
Const
. If you have..then look into the main VE tables...or other supporting tables. Well what have you done so far? You also have to mod the DE (decell tables) too..they affect base palse directly too.

[93gtpdohc]

the injectors are stock injectors off of 97 gen 2 3800 SC, and i am useing tunercat which use's the BPC for the injectors, i don;t see a de accel table anywhere,

[SappySE107]

the fuel constant doesn't do shit other than gas milage calcs for a dash puter to spit out at you. Its the EGR vs BPC you need to change.

[Cliff8928]

the fuel constant doesn't do shit other than gas milage calcs for a dash puter to spit out at you.

So that's how i need to fix that, I knew my 3400 wasn't getting 40 MPG!



Cliff Scott
89 BerettaGT
04 AleroGX

[SappySE107]

hahaha, yeah, though it would be nice now wouldn't it:P

[93gtpdohc]

so how would i cal that for the #36 injectors?

[TurboGTU]

I got this from a P4 PFI for a 2.0 turbo..might want to get the one from tunercat for the 8f to read up on its workings..

Base pulse width calculation
The base pulse width calculation for fuel delivery:
BPW=BPC*MAPP*T'*A/F'*VE*F33c*BLM*DFCO*DE*CLT*F77

Where:
BPW= BASE PULSE WIDTH
BPC= BASE pulse constant term
Mapp= Manifold pressure term
T'= Inverse temperature term
A/F'= inverse air fuel ratio term
VE= Volumetric efficiency term
F33c= Battery voltage correction term
BLM= Block learn correction term
DFCo= decel fuel cutoff term
DE= Decel enleanment term
CLT= Closed loop correction term
F77= TURBO BOOST MULTIPLIER

You can see that DE has a dramatic effect on PW. ALso the Turbo boost multiplier has a major effect. Thise variables/constants/tables are all connected.
Heres why the BPW vs EGR is the closes to Get the BPW right on upgraded INJECTORS..

The following computation shall be used to obtain the airflow (1bit=0.25 grams/sec.) through the engine

Air flow= BPWM*KAIRF~w*218*KNUMcyL*25*AIRFUEL*NTPRMx32
Where:
BPWM= Base pulse width for EGR
KAIRFLOW= Air flow multiplier
KNUNCYL= Number of cylinders*32
Air FUEL= engine running air fuel ratio*IO.
NTRPMX= computed engine rpm scaled 25 rpm/bit.

Notice the first cal. is the Base pulse width for EGR. If you adjust the 0 (zero) egr constant..you changed the whole equation for the larger injectors..when the egr is off..then you need to adjust after the zero value when the egr is on. SO the first table to change after changing the INJECTOR CONSTANT (hex address 0654) and INJECTOR FLOW RATE (0656)is the BPW vs EGR DC. Then go from there to other tables. But run test after you just did this table...she what she does on the ALDL monitor and a good WB02 sensor. The seat of the pants dyno works too.. Go on third or 4th gear..and load the SH&^ out of the engine after a good warm up and turn it off imidiately...let it cool and check the plugs. If they are black coated..try again.. lean it out more. If they are white as snow..enrich it. You'd want a good light brown ring on by top of the electrode. Light black woun't be bad for a turbo app. I would try and run it off boost first..see what she does..if its good...boost it...she what she does..might want to adjust the BOOST MULTIPLIER tables after this if its running too rich after the egr..then work on the DE tables..by GUNNING it and letting go immidiatly..if she stalls...check the DE tables.. But don't go by what I do...im sure someone has a better way..correct way to go about it.
heres the DE tables and what not...don't know where I got thise...
8B28 04 4 1.6 %TPS DECEL ENLEAN DELTA THROT ANGLE THRES
8B29 10 16 5 KPA DECEL ENLEANMENT DELTA MAP THRESHOLD
8B2A 50 80 1 SEC AE TO DE BLEND TIME
8B2B B0 176 0.68 MULT AE TO DE INITIAL BLEND MULTIPLIER
8B2C 08 8 0.03 MULT AE TO DE BLEND MULTIPLIER DELTA
8B2D 80 128 1.6 SEC PE TO DE BLEND TIME
8B2E 60 96 0.375 MULT PE TO DE INITIAL BLEND MULTIPLIER
8B2F 03 3 0.01 MULT PE TO DE BLEND MULTIPLIER DELTA
8B30 80 128 0.5 MULT D.E. MULTIPLIER WHEN TCC LOCKED
8B31 80 128 1 MULT D.E. MULT WHEN CONV OT PRESENT

DECEL ENLEANMENT FACTOR VS. NUMBER OF INJECTS IN DE
8B32 58 50 40 30 20 18 14 10 10 10 10 10 10 10 18 1C 20

DECEL ENLEAN FACTOR VS. DELTA THROT
8B43 16 20 30 40 48 50 50 50 50 50 50 50 50 50 50 50 50

DECEL ENLEAN TERM MULTIPLIER VS. NMPH
8B54 00 00 00 00 00 80 C0 E0 FF

DECEL ENLEAN TERM MULT VS. NMAPLD
8B5D 28 28 30 30 38 38 40 40 40 40 40 40 40 30 20 10 10

DECEL ENLEANMENT FACTOR VS. DELTA MAP
8B6E 08 0C 10 14 18 20 24 28 30 40 40 40 40 40 40 40 40

DECEL ENLEAN TERM MULT VS. COOLANT
8B7F 10 10 10 10 10 30 50 50 40 40 40 40 3C 38 30 20 10