New engine, first start up tune ?

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antus
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Re: New engine, first start up tune ?

Post by antus »

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.
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Jaso74
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Re: New engine, first start up tune ?

Post by Jaso74 »

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 ?
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Re: New engine, first start up tune ?

Post by vlad01 »

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.
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Jaso74
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Re: New engine, first start up tune ?

Post by Jaso74 »

Cool thanks , that helps heaps and exactly what I wanted .
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Re: New engine, first start up tune ?

Post by Jaso74 »

antus wrote: Mon Jan 29, 2024 11:27 pm
Jaso74 wrote: Mon Jan 29, 2024 4:35 pm Yep that's the nvram I have , ecm type for 424 ecu

For what its worth i'd always recommend getting an eeprom programmer that supports the chip too, as accidentally uploading an incompatible file or short circuiting the read/write wire you need to solder in to the case against the pcm box will also damage the data on the chip. That's frustrating to then have to wait for a programmer at that point, so if you can, it's probably worth getting one now so should that happen you are able to recover on the spot. That advice goes to everyone running an nvram setup. Usually a gq4x4 from mcumall.com or darkwire.com.au or a TL866-3G from ebay are good options. The GQ has better software, but the TL866-3G is cheaper and can still get the job done.

Do you need an adaptor to plug the Nvram onto the eeprom programmer or will it plug straight onto it ? Ideally wouldn't want to be taking the chip off the nvram I'm assuming to put onto the programmer ?
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