Geniii abc evc ivo eoit
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Geniii abc evc ivo eoit Don't see so much talk about this these days, but if you get my posting jargon I'd love to have some modern insights from the old salts around here. This is can help economy and driveability with a lot of setups if done right. Still like anything else when tuning some of the more unique and especially less than ideal setups, (at least from the tuners point of view) only trial and error will get you there.
I thought I had it as good as I could get it until I start playing with this, every little bit helps and nothing is ever perfect but you can always make it a little better, and that's why I love building and tuning so much
I thought I had it as good as I could get it until I start playing with this, every little bit helps and nothing is ever perfect but you can always make it a little better, and that's why I love building and tuning so much
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I'd love to see any tools, rules of thumb, or spreadsheets you guys have come across, specifically how the compression and valve events would dictate a generalized starting point for someone who's experiment with this extensively. From what I've read through my own research it seems most choose a specific valve event, duration, or overlap to come up with a value. Most don't mess with the boundary, I haven't really either. I think it'd be really helpful if we could find users that's setups really benefited from making changes here
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https://forum.hptuners.com/showthrea...ight=injection
Very interesting old thread that sadly ends all too quickly. This was back in '07 when HP tuners first added the injection timing boundary makeup and normal tables to be edited in the software.
If I can remember my password maybe I'll go on there and stir up some s***
Very interesting old thread that sadly ends all too quickly. This was back in '07 when HP tuners first added the injection timing boundary makeup and normal tables to be edited in the software.
If I can remember my password maybe I'll go on there and stir up some s***
I adjust it a bit on larger cam/injector setups, does it really make much of a difference though? Not as much as some people would make you think. Even on huge injector setups with big overlap cams, it's just not a big factor in the grand scheme of things. If you tune standalones and can directly change those types of tables in real time you get to see the changes take effect immediately, and it's underwhelming especially if you read some of those threads and how people talk about it. The OEM stuff is basically the same just laid out a bit differently and has the same results.
I adjust it a bit on larger cam/injector setups, does it really make much of a difference though? Not as much as some people would make you think. Even on huge injector setups with big overlap cams, it's just not a big factor in the grand scheme of things. If you tune standalones and can directly change those types of tables in real time you get to see the changes take effect immediately, and it's underwhelming especially if you read some of those threads and how people talk about it. The OEM stuff is basically the same just laid out a bit differently and has the same results.
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wish I could see that calculator I never got it to open.
I have to say I played with this for a while and I found my car really responded to a later normal value. And while it's probably not a drastic change HP wise it's certainly part of the engine manners puzzle , especially If you have a Gen 3 drive by cable setup where the only variable is engine temperature so you are "stuck" with the same value until the engine speed and injector duty increase enough that it doesn't matter, the newer stuff goes by temperature and RPM so if you have your own tuning software and you want to keep tuning. Mine sounds much smoother idling even with reduced timing it hid the cam a lot. The exhaust odor is much milder and more pleasant, but driving away It's really meaner sounding) it's worth playing with eoit so long as you don't mind retuning the VE table a little bit.
So If you have a later intake valve closing event and some decent exhaust overlap you may find moving the normal boundary out some and retuning the VE can definitely clean up the idle and the low speed stuff from where it was set stock, at least it did on my setup.
Play with it if you dare you can always change it back If you can't figure it out but if you're set up likes it and you get it to your liking it's really nice, any perceivable benefit to me if I can get my tune to run cleaner and sounding better to "my ear" Just by playing with the software a little more is worth the time for me if I can find it
I have to say I played with this for a while and I found my car really responded to a later normal value. And while it's probably not a drastic change HP wise it's certainly part of the engine manners puzzle , especially If you have a Gen 3 drive by cable setup where the only variable is engine temperature so you are "stuck" with the same value until the engine speed and injector duty increase enough that it doesn't matter, the newer stuff goes by temperature and RPM so if you have your own tuning software and you want to keep tuning. Mine sounds much smoother idling even with reduced timing it hid the cam a lot. The exhaust odor is much milder and more pleasant, but driving away It's really meaner sounding) it's worth playing with eoit so long as you don't mind retuning the VE table a little bit.
So If you have a later intake valve closing event and some decent exhaust overlap you may find moving the normal boundary out some and retuning the VE can definitely clean up the idle and the low speed stuff from where it was set stock, at least it did on my setup.
Play with it if you dare you can always change it back If you can't figure it out but if you're set up likes it and you get it to your liking it's really nice, any perceivable benefit to me if I can get my tune to run cleaner and sounding better to "my ear" Just by playing with the software a little more is worth the time for me if I can find it
Last edited by stockA4; Jun 14, 2023 at 11:36 AM.
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I agree that adjusting the injector timing to start a good 10 degrees after the intake valve opens to ensure the exhaust valve is fully closed will improve idle and smell. Of course only if your performance cam has overlap.
The calculators can be tricky to use because some work on crankshaft degrees, some on camshaft degrees, some on TDC, some on BDC. And the Holley EFI (e.g. Dominator) use a different reference point than the GM EFI.
FYI, the Holley Dominator calculates reasonable values after you enter your camshaft open/close values.
However, its unlikely to make a significant (any?) performance difference because under WOT, you injector are typically squirting 80% of the time anyway
The calculators can be tricky to use because some work on crankshaft degrees, some on camshaft degrees, some on TDC, some on BDC. And the Holley EFI (e.g. Dominator) use a different reference point than the GM EFI.
FYI, the Holley Dominator calculates reasonable values after you enter your camshaft open/close values.
However, its unlikely to make a significant (any?) performance difference because under WOT, you injector are typically squirting 80% of the time anyway