pcmhacking.net

No, if you do that you'll end up chasing you tail. You're best not to lie to the computer about your inputs. If you have changed the injectors or run non-standard fuel pressure use the kinjflow calculator to calculate the right injector flow rate, and also adjust the stage 1 and state 2 cranking tables by the same percentage difference in the flow of the old and new injectors to set the cranking fuelling. You can make changes to the injector flow rate if you run out of headroom in the VE table, to scale the whole thing down and make more room, but don't start with that unless you find with your engine mods you need too. There are a lot of related parameters in these computers and ideally you don't need to change most of them if you keep the setup clean and truthful.

Okdokey. I was just trying to think of a method for leaning mostly for that initial start up and camshaft run in.
After that is done tweaking the ve cells using the wideband afr reading would be in theory not so stressful as the cam run in done and hopefully haven't washed down the bores with fuel in the process.

So is there a good method other than a guess at figures prior to start up or suggestion of where to start ?

I just drop the injector flow parameter down, maybe try dropping it down 70% of the original value. I found at least with my engines, running in neutral, they are fine right up to the WB is pegged lean without any issues, like 19 AFRs they run fine.

If it's too lean it will just run with a bit crap but it wont do it any harm as it's not under any load. Once it is running and beding in the cam you can real time tweak it up as needed if it's way too lean. Much better than going the other way and having to try to get it to run and flood the shit out of it, just like I did because I used injectors twice the flow of stock but didn't know about one of the most over looked settings, min cranking BPW, make sure that value is well below the lowest cranking pulse you expect to ever see in your cranking tables after they have already been adjusted in difference from old to new injector flow.

I missed mine and totally stuffed up the whole "don't run it rich for the first time" thing. Fouled the plugs bad too, backfiring like a GAU-8 letting loose. I set all my tunes to 2ms, so I can never go wrong when modding engines and what not.

Cool thanks , that helps heaps and exactly what I wanted .

You pull the nvram off the assembly and put it direct in the programmer. use a small flathead screw driver and lift it up a little at one end, then the other, then back to the first and so on and be careful not to bend the opposite corner leg when it comes off. when re-installing go gentle and make sure all the legs are going in and none are bending. The end of the chip with the white dot goes the end of the socket with the notch in it.

Thanks for that .
I might be actually getting close to trying to burn a tune to a spare memcal one of these days .
I'n guessing a std memcal will slot onto the programmer also without adaptors ?
I suppose I will have to order a uv jiggy to wipe it too before reprogramming

If it's a '424 and you are putting 11P on the standard memcal it'll fit. But they're very old and they don't have electronic erase. So you need to get a UV eraser and pull the sticker off the chip and erase it with UV light. Most people replace the chip with an electronic erase version, and make up an adapter with a piece of vero board and some rows of pins so that they can plug the memcal in to the programmer directly. Its fiddly work, intermediate soldering skill as there is lots of plastic to melt trying to get it together. I tend to use a small flathead screwdriver to push the pins on the original chip inwards until they make a small pop sound and you can fell the factory solder tare between the chip and the carrier. Do that for each pin. Then lift at the end and you'll find some are still holding and you can give them a push with the screwdriver until they pop. Then you have to solder a socket in the top, this is where the plastic melt happens. So you need to gently sit the socket on top of the carrier and solder each pin without creating any shorts and idealy melting minimal or no plastic. Then plug the memcal adapter you made in the bottom of the chip and install the eeprom in the top and check you do have continuity on every pin from the pin leg on the chip, to the pin at the bottom of the adaper at the other end. I tend to walk along the edge, verify you have connectivity where you want it, then dont have connectivity to the next pin. Then repeat for all the pins. at the end the memcal lid probably wont fit back on so just leave it off. If you are unsure of your soldering skills to pull this off, seek help from someone more experienced to avoid frustration, wasted time and damaged hardware.

Gee almost sounds easier to have a spare nvram with back up loaded on it . Although I know that isn't really an option as the battery goes flat in the chip eventually anyway .

eventually, yes. 8-10 years is a long time. Its such a pitty electronics shops that do this sort of stuff are so rare now.