Looking for a tune file for a L31 Vortec 350 with an LT4 Hot Cam ported heads

[Snipescastle2]

Hello everyone!
I want to open up by saying I’m very impressed by the knowledge and experience shown
here by everyone I have read posts from!
I am in the process of converting my ‘96 Trans Am to a 0411 PCM, basically, going to eliminate the
electronics of the LT1 “Optispark” distributor by wiring the engine as a L31 Vortec 350. The dizzy will
function as just that, a cap and rotor to fire the plugs. Since my ‘96 has the reluctor wheel/ crankshaft
position sensor in the timing chain cover,I’ve already got most of the necessary pieces on hand.
the rest is just “Re-pinning” of the harness to the new PCM.
I have built a 383 Stroker LT1 engine for my car with ported Factory aluminum heads that have been milled, should be good for 11.5 compression. I’m going to run the LT4 “Hot Cam” with 1.6 rockers, long tube headers and 24.lb per hour blue top fuel injectors, a Truck MAF and stock Map sensor
. I am reworking my wiring harness to remove all the pollution equipment, rear 02 sensors
and all the Cats.

does anyone have a tune for a L31 Vortec 350 running a mild cam and headers that would get me close
so I can get this combo up and running? I have built an ALDL cable interface to data log once I get it up and running. Any help would be greatly appreciated!!!!
Thank You!
Ben Smith

[dave w]

If I'm understanding the project description correctly, it's going to be based off of the '0411 low resolution 4x crank trigger and 1x cam trigger operating system?

dave w

[Snipescastle2]

That would be correct Sir!
Ben Smith

[dave w]

Stock gearhead-efi L31 .bin files are available here: http://www.gearhead-efi.com/Fuel-Injection/showthread.php?1513-2002-TunerPro-Bin-Files

Posting modified files in the library is not encouraged. Posting a modified file in a thread is OK, hopefully with information about what was changed and / or the base file is also posted.

dave w

[Snipescastle2]

David,
Thank you for pointing me in that direction! I was merely hoping someone else who might have a similar setup could
give me a “jump start” in getting my project going. I’m new to this tuning process, “gotta crawl before you walk” ya know?
Thanks again!
Ben Smith

[dave w]

I understand the desire to get a jump start with a tune.

According to Wikipedia https://en.wikipedia.org/wiki/Chevrolet_small-block_engine#LT4 the .bin from a 1996 Corvette six speed will have the LT4 camshaft parameters. Maybe you can find the .bin file for a 1996 Corvette six speed? Interpolating the the LT4 timing tables into the L31 .bin would help if you need to build a tune yourself.

dave w

[Fast355]

I understand the desire to get a jump start with a tune.

According to Wikipedia https://en.wikipedia.org/wiki/Chevrolet_small-block_engine#LT4 the .bin from a 1996 Corvette six speed will have the LT4 camshaft parameters. Maybe you can find the .bin file for a 1996 Corvette six speed? Interpolating the the LT4 timing tables into the L31 .bin would help if you need to build a tune yourself.

dave w

Interpolating a MAP based timing table into a Cylinder Mass based timing map might get a bit interesting.

LT4 Hotcam also likes a pretty different timing advance table than a stock LT4.

[dave w]

Is MAFless an option?

dave w

[Snipescastle2]

Dave,
I’m open to suggestions! I just want this engine to run good, with minimal issues. What do you
recommend?
Thanks!
Ben Smith

[dave w]

I'm thinking a MAFless tune is a good plan. I own an EFI Live system, which has the special operating system software. The cons to EFI Live is it's not budget friendly and a learning curve for a novice tuner. I'm not sure what HP Tuners offers for MAFless, but likely has similar MAFless system software and cons like EFI Live.

Have you talked to some of the tuners in your area? Maybe it's a good plan to get the 383 started / running on slightly modified stock tune, and complete the tune with a local tuner?

dave w

15966

[Snipescastle2]

Dave,
What, if anything would this cost me to have done? My wife is already on me like
“stains on a shirt” about all the money I have poured into my car, just trying Not to spend
more than I have too. I have Tuner Pro RT now, and I’m planning to get the OBDlink MX
and the ALDL Droid app to program the PCM. Any Ideas how I can make this work with the
equipment I mentioned?
Thanks!
Ben Smith

[dave w]

I'm clueless what a MAFless '0411 tune / flash would cost.

There could be a challenge converting an EFI Live custom OS .tun/.ctz file into a .bin file. It's unlikely there are .xdf files for a custom operating system.

dave w

[Snipescastle2]

Well, i’m gonna start with an express van tune and go from there.
I’ve looked for a stock 1996 LT4 .bin file, but haven’t found one yet.
guess I’ll just wing it once i get all my hardware together.
I did find someone that has a similar setup that sent me a copy of his tune
for a 383 with a hotcam setup, but its an “HPTuner” file, and I don’t
have HPTuners. If I can open a trial version and print off the spark and
fueling tables, might get me close.
Thanks again!
Ben Smith