So the car is getting close to finished. Waiting on pushrods from Manton and when they arrive I'll finish the motor and drop it back in the car. I'd like to be able to fire the car up when finished and do the break in 2000-2500 rpm to temp for about 20 minutes then shut it down, drain the oil and check the filter. Once everything looks ok I'll refill it and fire it up to load on a trailer to take for dyno tuning. What I'd like to be sure is the tune I have now will suffice do the break in and load on the trailer. If anyone well versed in tuning could take a look and give me some feedback I would appreciate it.

The original tune was done by Vengeance Racing for a stock displacement and compression LS3 with Vararam Intake, 227/239 .612/.612 112+4 cam, ARH 1 7/8 headers, TR6060, Lingenfelter 9.5" diff with 4.10s.

New engine is LS3 based ERL 427, 11.5:1, Vararam Intake, ported LS3 TB, Ported FAST 102, Bosch 60lb injectors, ported TFS 255 heads, bigger cam (high 230's intake and high 240s exhaust, .620s lift and 113 +1), ARH 1 7/8 headers with no cats. I took the tune from Vengeance and adjusted the IFR, Injector Voltage Correction, Default Pulse Width, Injector Short Pulse, Small Pulse Adder, and Injector Offset. These adjustments were made using date provided by Fuel Injector Connection for their injectors. All this was done on EFI Live. I am by no means a tuning guru but trying to learn. Final tune will be done by a professional. I have dual widebands so I can monitor AFR to make sure I don't get dangerously lean or rich during the break in. I do not plan to run SD tune.

So any help from the knowledgeable ones is much appreciated. Thanks again.

UPDATE: So looks like I can't add a ctz file so I guess the big question is will modifying the injector tables for the larger injectors be enough or are there other tables that will need to be changed just to fire it up and runn at low throttle for the break-in. Thanks.

 

Can't imagine that the tune for a stock head 6.2 with a small cam will be even remotely close to one that's needed for an aftermarket head 427 with bigger cam. I'd get a base tune for that displacement before even starting it.

 

change the base parameters. IE cylinder volume, injector size, base idle set high for now(1000ish), and add a bit of timing at idle speeds should get i started and idling. Driving NO but enough to do a quick warm up. you may need to add some to the RAF to get idle to stabilize. That again is JUST for a start up. Pro tuning is a must after its ready.

 

I agree a base tune is best option. I'll work on that just in case but if I can do it on my own I'd like to. I'm going to take a look at some of the other parts of the tune and see if I can dial it in a little closer. Wish I could post the damn tune so it could be seen first hand though. Thanks.

 

^^^ This !!!
Without adjusting that up, you will be extremely lean. (A MAF might account for that, but MAF output has to agree within reason with other calculated values.)
The injector values are critical, but sounds like you have that covered.

 

Everyone seems to have you covered pretty well. If you are using the same intake, tubing and MAF, and it was properly tuned before, and you used correct information for you injectors, then you could put it into MAF only and it should be good to go. Thats just a lot of if's.

 

Yeah, its a lot of "if's", but it should work.
Also, keep your HPT scanner running as you start it up to monitor everything.
It will also let you override the commanded AFR to force the wideband AFR into a safe range.

 

Make sure you have the proper injector data in before you start it. You don't want to wash down the cylinders.

 

Get the injector data in there. Otherwise you'll wash your cylinders down.

 

Ok I adjusted the cylinder volume to reflect the new engine size. Was .77 and now is .88.

Idle is set to 1000 when cold and 950 warm.

All the injector data was set in accordance with and using data from Fuel Injector Connection.

Also, I am using EFI Live.

Seems things I need to be concerned with include washing the cylinders which I have taken care of.

Increased idle speed. Done.

What I am concerned with still is adjusting for the ported TB and ported FAST intake. Essentially keeping the motor from running away from me.

Anything else I should be looking at?

Thanks again for dealing with the noob tuner. Pushrods showed up tonight so might be starting the shoe horn back in place this weekend.

 

You could post your tune here; tell us what model and size injectors you have.

 

Would like to but it's a .CTZ file and wouldn't post.

The injectors are FIC 631cc 60lb 3 bar long body.

 

Why would the motor "get away from you"? Also the raising of the idle is a bandaid that your tuner can fix later. I'm unfamiliar with efi live do they have something like the HPT vcm controls? They allow you to set a desired RPM, set an IAC position, command different amounts of timing, change stoich AFR, all in real time just for situations like this.

 

So I've read some stuff where guys did not account for the increased airflow and subsequently the engine idle shoots extremely high. Seemed to be tied to MAF settings, changing TB's, Intakes, etc.

All the things you speak of can be adjusted via EFI Live and yes they have the ability to do it in real time using RoadRunner VCM but I do not have that so ECM needs to be programmed correctly, or at least close, the first time.

All I am trying to do is get it close enough to fire it up, do the 20 minute up to temp break-in of the motor, then load it on a trailer to take it for professional tuning. My concerns are running too lean/rich, excessive knock, extremely poor idle, etc. Love the power and drivability that comes from EFI but in this case, I miss just being able to change metering rods, jets, and twist the distributor a little for timing. That being said, I do want to learn to do this effectively. Been reading and tinkering as I learn best that way. Thanks for the feedback thus far.

 

Values changed from stock LS3 tune to New ERL 427 tune. Just striving for a base tune to be able to fire it up.

Ok, I figure this would give a decent representation of what has been changed thus far. This screenshot shows what has been changed from the stock 2011 LS3 tune to now. Open for opinions and I can screenshot individual table of the new tune as well. Thanks.

 

There's a bunch of stuff in there that you didn't need to mess with to accomplish your goals. None of it should hurt anything as far as I can tell. If anything the changes you made in the min airflow, idle airflow might make it idle higher than nessesary.

 

Some the changes are actually from the first tune for the intake, Vengeance Racing Stage 2 cam, and headers. Changes were made to prevent the CAGS from activating as well as to reflect a change in rear gear ratio. I imagine that is some of the things you were referring to.? Changes I specifically made for the new motor were injector related and cylinder volume.

 

Gotcha. Carry on.

 

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.

 

That's a personal preference. If you look at different stock files you'll see GM didn't change it ever. As far as I have noticed.