Will It Work? Can I fire it up on this tune?
So this will either totally make sense or totally make me sound crazy. New bigger cam means valve events changed. Specifically, the intake is opening sooner. Should I be making an adjustment to have the injector fire earlier for proper evap of the fuel? Or is the existing tune good enough for idle to 2500 no load break in? Reading Greg Banish book Engine Management: Advanced Tuning which is what got me thinking about this. Thanks.
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Will It Work? Can I fire it up on this tune? 
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On to the injector timing. I have 47* of positive overlap on my cam. I added 1 to the whole table. and it Greatly improved pretty much everything. smoother idle, cruise, fuel smell behind car. I did have to adjust the low rpm VE a bit though. As more of the fuel was "staying" in the cylinder now. Don't know if that helps. I think it really should be done at first rather then after its close to properly tuned.
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On to the injector timing. I have 47* of positive overlap on my cam. I added 1 to the whole table. and it Greatly improved pretty much everything. smoother idle, cruise, fuel smell behind car. I did have to adjust the low rpm VE a bit though. As more of the fuel was "staying" in the cylinder now. Don't know if that helps. I think it really should be done at first rather then after its close to properly tuned.
But your comment is valid - the injector timing does affect the VE table, and therefore should be set, after some experimentation, before final tuning of the VE.
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Will It Work? Can I fire it up on this tune?
Originally Posted by mrvedit
For comparison purposes, we don't talk about overlap at .005" as you have done. Please give us your overlap at .050" which is what we talk about here. For example, stock might be negative -12*, high performance around 5* and extreme performance around 20*.
But your comment is valid - the injector timing does affect the VE table, and therefore should be set, after some experimentation, before final tuning of the VE.
But your comment is valid - the injector timing does affect the VE table, and therefore should be set, after some experimentation, before final tuning of the VE.
So if I am tracking, what's important is to know the intake valve open at .050. In my case that is 7 BTDC on a 113+1 cam.
So knowing that, what table should I be looking at and what should I be looking for?
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We should not have starting talking about Injector timing in your thread.
I suspect the vast majority of people do not change it, regardless of their cam.
The stock values will be just fine for starting your engine and performing break-in.
Once you complete break-in and have your VE table tuned within 10%, then you might
consider experimenting with injector timing before the final VE tuning.
I suspect the vast majority of people do not change it, regardless of their cam.
The stock values will be just fine for starting your engine and performing break-in.
Once you complete break-in and have your VE table tuned within 10%, then you might
consider experimenting with injector timing before the final VE tuning.
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Will It Work? Can I fire it up on this tune?
Originally Posted by mrvedit
We should not have starting talking about Injector timing in your thread.
I suspect the vast majority of people do not change it, regardless of their cam.
The stock values will be just fine for starting your engine and performing break-in.
Once you complete break-in and have your VE table tuned within 10%, then you might
consider experimenting with injector timing before the final VE tuning.
I suspect the vast majority of people do not change it, regardless of their cam.
The stock values will be just fine for starting your engine and performing break-in.
Once you complete break-in and have your VE table tuned within 10%, then you might
consider experimenting with injector timing before the final VE tuning.
I am going to zip the tune this weekend and post if anyone is willing to take a look at it that would be great. Thanks.
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Will It Work? Can I fire it up on this tune? You should be able to zip it by creating a Windows compressed/zip folder and copying the ctz file into it...
or you can use something like 7-zip (free) or WinRar or WinZip.
or you can use something like 7-zip (free) or WinRar or WinZip.
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You wont need to worry about it.
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Zipped Tune Attached Ok guys, I've attached the zipped file so let me know if that works. Looking forward to some feedback on what I have so far. Again, the goal at a minimum is to be able to safely fire this thing up, run it to 2500 RPM at no load for about 20-25 minutes for a break in. Just want to get rings to seat, check for leaks, get a good heat cycle so I can re-torque heads, headers, etc. Then it needs to run good enough to load on a trailer to head for final tune.
Details on the build can be found here:
https://ls1tech.com/forums/generatio...all-motor.html
So let me have it. Thanks!
Details on the build can be found here:
https://ls1tech.com/forums/generatio...all-motor.html
So let me have it. Thanks!
Just throwing this out there. If your start up tune dumps fuel, make sure you change your oil after the tune.
On mine the oil pressure dropped off, and when I drained the oil it smelled like gas. Fresh oil, and pressure back to 45 at idle.
I knew it was dumping gas, so no surprise but wanted to save you a panic attack
On mine the oil pressure dropped off, and when I drained the oil it smelled like gas. Fresh oil, and pressure back to 45 at idle.
I knew it was dumping gas, so no surprise but wanted to save you a panic attack
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Just throwing this out there. If your start up tune dumps fuel, make sure you change your oil after the tune.
On mine the oil pressure dropped off, and when I drained the oil it smelled like gas. Fresh oil, and pressure back to 45 at idle.
I knew it was dumping gas, so no surprise but wanted to save you a panic attack
On mine the oil pressure dropped off, and when I drained the oil it smelled like gas. Fresh oil, and pressure back to 45 at idle.
I knew it was dumping gas, so no surprise but wanted to save you a panic attack
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Code:
LABELS Injector Flow Base (Grams/Second) Delta MAP kPa Value 128 5.133056 148 5.520019 168 5.881103 188 6.220947 208 6.543945 228 6.851074 248 7.145019 268 7.427978 288 7.699950 308 7.962890 328 8.217040 348 8.464110 368 8.704101 388 8.937011 408 9.165038 428 9.386962 448 9.604003 468 9.815917 488 10.022948 508 10.226073 528 10.426024 548 10.621093 568 10.813964 588 11.001952 608 11.187987 628 11.370116 648 11.550048 658 11.727050 688 11.901122 708 12.072997 728 12.241942 748 12.408934 768 12.573973
Last edited by joecar; Aug 30, 2015 at 04:26 PM.
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Yep, factory fuel system. Only this different is bigger injectors and installed a ZL-1 fuel pump to provide more volume though still at 58 psi returnless. This is an all motor car also. No boost or spray.
Ok, this is his IFR table (if he has the factory returnless 400kPa/58psi system then: vacuum is roughly above 408 and boost is roughly below 408kPa):
Code:
LABELS Injector Flow Base (Grams/Second) Delta MAP kPa Value 128 5.133056 148 5.520019 168 5.881103 188 6.220947 208 6.543945 228 6.851074 248 7.145019 268 7.427978 288 7.699950 308 7.962890 328 8.217040 348 8.464110 368 8.704101 388 8.937011 408 9.165038 428 9.386962 448 9.604003 468 9.815917 488 10.022948 508 10.226073 528 10.426024 548 10.621093 568 10.813964 588 11.001952 608 11.187987 628 11.370116 648 11.550048 658 11.727050 688 11.901122 708 12.072997 728 12.241942 748 12.408934 768 12.573973