2gen 3.1 help

[88jbody]

I am planning on putting a bigger cam and a 3100 top end on my 3.1, and am looking for som info on a chip pre-programed for this or a chip that I can tap into with the laptop and program it my self, either is fine, I have a scan tool and access to a wideband air fuel meter, also are there any adjustable fuel preasure regulators out there? and what would be a good set of injectors to use?

thanks

[SappySE107]

You should use the 3100 injectors and not worry about the AFPR unless you really want it for some reason. As for programming, you will need to find the 6D code mask to edit the chip for the mods you are doing, especially the injectors.

[sharkey]

im guessing by 2nd gen you mean a 2nd gen j body.

if you use your stock ecm, you will need to use the 3.1l injectors and use an andjustable fpr. the 3100 injectors run at 55psi, were the 3.1 injectors run at around 43psi, and if you run them at 55, it will run extreamly rich. if you wanted to run the 3100 injectors, you would need the ecm, wiring harness, 4t60e tranny (cant run a 5 speed). in general, running the 3100 injectors and ecm has no benift other than some gas mialage. above a certain rpm (i think around 3500) the sfi part changes back to mpfi, so it has no benfit in power.

there are a couple companies working on chips for the 3x00 swaps, but i dont know if there is anything out yet. i know there isnt anything you can buy thats tunable, it would require a prom burner and a lot of chips (lots of $$$), or a reburnable chip (way more $$$). if you realy want to be able to tune the sucker, the only way is stand alone fuel and ignition managment. you could sit on a laptop and tune yourself to death with that, only thing is your looking almost $2000 for it.

[bszopi]

The 3100 runs at 43psi and the 3400 runs at 55psi...

[SappySE107]

no...just plain no. THe eeprom costs 6 bucks, thats not $$$ unless you can't afford 6 bucks in which case you wouldn't be doing this swap. The 3100 injectors don't require a new transmission and computer, thats just nonsense. You only need a program like gmpcm to edit the chip code, change the BPC vs EGR% for the new injectors, and tune from there. The AFPR isn't going to help you unless you want to run the stock injectors are a higher pressure to make them flow more, which would mean you dont need the 3100 injectors.

All the swaps I have seen wanting chips made readily available are for 3400 swaps, not top end swaps. I have a few chips done but not for a stock 3400, all modified. GPXSS has a chip code for a 3100 top end swap that you could probably base your own chip on but you would still need to modify the code more for your exact setup.

You will need a chip burner, an adapter to put the memcal into it, a 29C256 chip soldered into your stock memcal, and gmpcm to edit the code. You already have the scan tool and the wide band would be useful after you tune everything else since WOT is based off normal driving fueling.

[88jbody]

The reason for the chip is mainly because I plan on going to quite an agresive camshaft.

[sharkey]

sorry, i meant if you want to run 3100 injectors and a factory pcm.

[88jbody]

how agresive of a cam can I run without a chip?

I'm trying to get my engine up to 180 or so HP
it's last dyno run ran a 110HP and 187 tourque thant's mostly stock just exhaust and a k&n filter