INJECTOR SIZING

[chevette_boy]

HEY just wondering if u guys think 21# injectors would be suffecent to fuel a 3200 @ 7-10 psi i have a 1:1 FPR and a standalone.did the tgp's not run a 21# injector ? did the have a 1:1 FPR ?

[germ]

i dont think they will hold up to the amount of fuel you will need

36# from a GTP would do the trick for sure depending on what application they are used on

[SappySE107]

You will want to have SFI though for 36# injectors. MPFI will run a bit rich at idle using that size from what I have read. TGP are clost to 21 though I thought it was 22 or 23. Been a while and we don't have many TGP owners on this site unfortunately.

[germ]

that may be true, however, i would rather be rich at idle than lean at WOT.



is there a way you can tune the ECM for them Ben? im not familiar with obd1 setups but do they have an Injector Flow Rate table or Injector Cycle table? changing the values in the IFR table is how we obd2 guys tune for different injectors. basically is a ms/g table (milliseconds to deliver 1g of fuel)

[Turbo v-sick]

Hey guys I'm new here but I've been messin with the TGP code for a while now.I have found that you can tweek the rich/lean 02 threshold at idle.The way it's set up from the factory is that .50v is stoich(14.7 to1)If your runnin richer than that at idle you can lower that number to lean things out or if ur lean you raise that number to richen it up.Oh well thats jus my 2 cents worth,hope it helps..

[TurboGTU]

Well with the OBD-1...theres no such trasfer table like that....well not directly like a maff transfer curve.


Its much more complex.

THe EGR table is the "maff trasfer table" for OBD1.
The base injector pulse can be increased or decreased with this table.
BUT for short term and long term to work correctly, the Actual injector size has to be known by the ECM. THe term count is like the ecm ajusting the carb screws..and long term is like it ajusting jet size...if it doen't know the injector size...and you have fat ones on the car...It can start counting short term and ajust too fast and will program long term to overshoot and prob shut the injectors off.

Sometimes the EGR table is not enough or the fueling charicteristics of the injectors are too different for the engine to correct right. This is when you need to move Volumetric Effeciancy tables.

THe TGP code has basicly the same tables the sy/ty $58 code has except its overkill in features.
Main VE Vs rpm- ←WOT table
VE Vs TPS and Map- ←part throttle
Idle VE vs tps and map- ← closed throttle
Boost multiplier table- ←under boost. It adds that fuel to what ever table its on VE.
and many more. but those are the most important ones.

The final twiks are the BPW multiplier vs voltage and IAC. Even OBDII has to have thise moded.

THe problem with just moving the O2 setting is that it will run rich all the time or lean all the time after block learn...if for some reason it does work. The other problem is that the ECM doen't always work off the O2 sensor like in open loop.

[germ]

well, thats just ghey


obd2 sounds like it is so much easier to tune

[Turbo v-sick]

Yes your right,the TGP code is a complex as it gets for what it does and to top it all of the public ecu file is about 60% accurate.I am runnin ford 36lbers on my slightly modded TGP.To acheive a desireble part throttle tune I changed the injector constant(36.to match the injectors and played with the base pulse constant vs desired egr and the ve tables.After that I changed the closed loop enable temp to an unreachable temp so no closed loop.I test drove my TGP and recored data from my wide band and made changes to the cold engine temp dependent afr and some more changes to the ve tables along with some stuff i cant think of and I dont have my notes in front of me.To make a long story short after all of the open loop stuff was done closed loop fell right in line except for it was a lil rich at idle so I played with the rich/lean o2 threshold at idle and it seemed to cure the problem.It's what worked for me but with most of the tuners I know I'm always doin something wrong.I say to each there own later

[TurboGTU]

I know what your saying Turbo v. One..I had to compleate and correct the Winbin Code mask I had. Idle ve was wrong and the fuel constant was wrong along with adding more tables. But also..the ECM doen't sense sensors like it should. I can see where you messed with O2 on that one. I was mearly pointing it out for those that don't know how to tune that just O2 readings changes won't work. MY aldl scanner says that my rev limit is at 5500rpm..while on the chip I put 6500 and the tach says 6500. Nothings perfect.

Hey..OBDII isn't a walk in the park either. THe thing about OBDII is that scanners are dime a dozzen and basicly complete. Code hacking isn't complete like OBD1 on some and you have to have a flash programer or keep a programmer on the ALDL port at all times.

Each has its own advantage.

OH yea...at about 220hp to the wheels..the TGP 22lbs are about 100% Duty cycle. YOu better shoot for 29-35lbs.