jeep cj wit a vortec 350

[annandaleoneton]

Hi all, I will be installing a L31 in my CJ in place of the old school 350 that is in it. I converted it to a TBI last year and will be using that unit on the new engine. I will have to look to see what computer it has but assume i will need to replace it or the chip for the new engine to run. I know nothing about how to tune one so would love to know someone that does that can hook me up. The Jeep is a rock crawler on 40's with a sm465 trans and 5.38 gears so its not gonna be a race car but id love it to run its best !

[dave w]

I often wonder why "Myth Busters" would not broadcast an episode on TBI tuning and the associated myths about TBI tuning.

Myth 1. A chip from a similar vehicle / similar engine will work correctly for my vehicle .... Plausible?
Myth 2 A chip programmer only needs to know the engine build specs for a "tuned chip" .... Busted!
Myth 3 The 1227747 computer "runs its best" without a VSS .... Busted!
Myth 4 The 1227747 is the "Best" TBI computer ... Busted!
Myth 5 TunerPro RT is the "Best" TBI tuning software ... Confirmed!!
Myth 6 Wide Band O2 (WBO2) is the best tuning tool ... Confirmed!!
Myth 7 The 16197427 computer is the "BEST" TBI computer ... CONFIRMED!!

In my humble opinion, to achieve TBI to run at its best, a TunerPro RT collaboration between the vehicle owner and tuner is required.

Are you up to speed with TunerPro RT to get hooked up with a tuner?

dave w

[annandaleoneton]

Not at all up to speed. I have confirmed i have the common computer. I have read a little about tuner pro rt. Still all looks like greek to me. I wont get the engine swapped until Jan. But want to have all my ducks in a row come time to fire it up for the first time. I would live to give my specs to someone that could tune my chip for me. At lest the first time. Seeing how my rig is no race car im just wanting it to run nice and smooth without backfires and misses and stuff.

[dave w]

There is lots of good 1227747 ECM information here: http://www.gearhead-efi.com/Fuel-Inj...Information-42

TunerPro RT can be downloaded here: http://www.tunerpro.net/downloadApp.htm

I use ALDL data logging cables from: http://www.aldlcable.com/products/aldlobd1u.asp

dave w

[annandaleoneton]

Man I'm a little overwhelmed so far, thanks for all the great info. Im still trying to get my head into it. From what i can tell, my engine will run best after loging info and adjusting as needed. Im still not sure how . Looks like from a piece of hardware of some sort. So until i really get more reading in, it sounds like lap tops hooked to my computer to read the info with tuner pro. Alot more involved than i expected to get involved in. Id love a known plug and play method to make the engine run without major flaws. If i leave 5/10hp on the table im ok with that as long as it runs smooth. Like I said ,not a race car so im not trying to beat my best time .

[dave w]

I agree, tuning is overwhelming.
Tuning the TBI is similar to tuning a carburetor and an adjustable vacuum advance distributor. The TBI computer controls both fuel and spark advance. The TBI computer will report back rich / lean fuel conditions and spark knock. The data log is really a recording of the engine running, that can be exported to a Microsoft Excel spreadsheet. Tuners like myself and other gearhead-efi.com member will "crunch" the spreadsheet to determine what correction are required in the chip for rich / lean and spark knock. The chip also controls things like "Choke" "Acceleration Enrichment" (carburetor pump shot) and "Power Enrichment" (similar to a 4 barrel carburetor secondary opening).

Short of taking your Jeep to a "tuner", I don't know of any Plug-n-Play tuning method.

dave w

[1project2many]

Id love a known plug and play method to make the engine run without major flaws.

Make friends with someone who can tune it for you. If you put the TBI and 4 speed on that engine you won't find a stock calibration that fits exactly. There is a calibration for a Vortec engine with TBI used in exported vans in 1996-97. BRDW It's fairly mild but it will work with the 16197427. I don't remember if anyone has released a Tunerpro definition but a stock cal is designed for use with a 4L60E and will throw codes if used with a manual trans.

[annandaleoneton]

I have 1227747 with a sticker showing AMUR4092 on it. So my next question is, who lives near DC that can help me tune it come January I would be in thier debt. I think I'm still WAY to new at this to pull it off myself I do believe. Oh and Merry Christmas!!!!

[dave w]

I would be willing to help remote tune your Jeep, when you are able to data log and burn chips 27SF512 chips with the Moates.net Burn2 chip programmer (http://www.moates.net/burn2-chip-programmer-p-197.html).

I would be willing to modify your 1227747 for a 27SF512 chip, see related thread http://www.gearhead-efi.com/Fuel-Injection/showthread.php?172-7747-Flash-Chip-Conversion-%2827SF512%29

Send me Private Message (PM) if you have questions.
dave w

[annandaleoneton]

So im going to need the cable, the chip burner,a chip,and the chip socket and install it into my 1227747. Ok. All seems do-able. Could I buy any good 1227747 computer off ebay and install the chip socket in it then just swap computers come time to run it? I assume installing the chip socket doesnt effect the way the unit works so it can run and gather data to know what to burn a new chip to?

[dave w]

You have figured out the tuning process.

When the 27SF512 ZIF socket is correctly installed, and the 27SF512 chip is correctly, flashed the 1227747 computer will operate like it did with the old chip. The old chip can not be erased and burned with the Moates.net Burn 2, which is why the 1227747 is modified for the 27SF512 chip.

The tuning process is basic; the tuner will send a chip file that will be set up to the your engine specs. You will you burn the tuner's chip file into the 27SF512 chip using the Moates.net Burn 2. After you get the engine running and driving you send a data log file (via email) to the tuner and tuner will send a chip file (via email) that you flash into the 27SF512 chip. Rinse and Repeat until tuned.

dave w

[annandaleoneton]

Im catching up. So just in case i do something wrong i think i will try to install the socket on second unit. Any recommendations on a reliable source for a used one. I see them on Ebay for like $45. Or should i get one somewhere else?

[dave w]

Ebay is a good source for a 1227747. Sometimes it can be hit or miss at a salvage yard finding a 1227747. Sometimes salvage yards will add fees to the price of a 1227747, like core charges and environmental fees.

dave w

[annandaleoneton]

Man, thanks for all the help. Once I get closer to to needing to tune I will be getting in touch. You said you would provide the first chip with a general tune to get started right. Whats the cost of that?