How do I tune TBI for Nonstock Performance?

[78 Chevyrado]

The only real way to tune an older OBD1 Vehicle is to get a pre-made Chip and just swap chips.  you'll have to find a chip maker you think you trust and tell him as much about your truck as you can, leave out no details as far as the engine is concerned, and they'll take that and burn you a chip like you want.  They used to sell "flip chips"  that had a toggle you mount somewhere and had two tunes inside, you could switch between the two any time you wanted.   My dad has one on his truck, on one setting its higher performance (you can feel it) and you have to run 91 octane in it.  the other setting is basically stock.  he has it like this so he's not stuck buying 91 octane when he doesnt want to.

[xCaliC10x]

Well, I will tell you this, I am new to the Chevy world, but I have been around the euro VW/Audi BMW scenes for a LONG time. Working on and modding cars for a living, I would NEVER sell something under false pretenses, or sell my customers something I think would be problematic, or less then I would put on my own car. You should thank him. Seriously. He probably is frustrated, like most of us here, about a customer that wants his cake, and to eat it too. 87 octane and high good performance do not go together. If you are worried about economy, go get a Honda Civic. .20 cents on BOTH my 16 gallon tanks on my C10 is about the price of a burger from Carls Jr. Big deal.

[Blue 82]

You can spend $350+ for custom tuning
Which consists of:
Burn a chip
datalog*
burn another chip
datalog
repeat till you get it right.....

Or you can do it youself with one of these
http://www.dynamicefi.com/

*datalog
http://winaldl.joby.se/aldlscreen.htm

[Da67goatman]

I have that program already, but have no idea how to use it.  I know I am going to end up doing it myself, I always do, but I always ask first, just in case there actually is an easier way.  I guess I'll take my truck and Laptop to the local college and get a group of students together and see if we college kids can figure out how to tune this old pig.  Thanks guys.

[Da67goatman]

I really like this idea of doing it myself with this:

http://www.dynamicefi.com/EBL_Flash.php

Anyone ever used this before?

[Blue 82]

I'm thinking about getting one for my 89 K1500 vs getting a over the counter chip from TBI Chips
I installed a fresh engine in it 6000 miles ago,
and just finished installing a new single exhaust on it.
Prior to the exhaust it will outrun my buddies 2007 F250 Powersmoke diesel from a 20 mph rolling start (1 truck length @ 70) and he's got the 60hp chip/tune whatever the heck they have for Fords. (it pulls better with the new exhaust)
I want to get all the engine mods in place before I attempt to tune it.
No use getting it tuned only to make changes to it, which would require re-tuning

The truck runs good now, but I know it could run better
At full throttle runs I'm getting steady 780mv at the O2 sensor with the new exhaust
with the true duals/glasspacks I was getting high 800's


All work is on hold till after the holidays

here's the build
TBI 5.7 2 bolt block
H345 +.030 pistons/ speed pro moly rings
ZZ4 balancer/ balanced stock rotating assembly
193 heads (ported) LT1 valves (new) Serdi valve job, decent valve springs, stock retainers and Felpre seals.
L98 roller cam/lifters/pushrods/ new Stamped 1.5 GM rocker arms
LT4 timing chain
Stock TBI intake
Ebay stainless shorty headers
Magnaflow Y pipe w/high flow cat
Thorley (Jardine) 3" single exhaust.
Stock (untouched) GM throttle body with unknown milage injectors

It idles so smooth you could stand a nickel on the air cleaner
I built for low end torque to pull my boat

After the holidays, I'll look into getting the Dynamic EFI unit

[grinder1989]

Just go buy a carburetor.  No chips, no technology, no problems.  Once you learn how to tune them, they are cake.

[VileZambonie]

Just go buy a carburetor.  No chips, no technology, no problems.  Once you learn how to tune them, they are cake.

No problems? I know how to tune a carburetor but there are plenty of problems. A carburetor will never be able to outperform a computer for versatility and fuel economy. TBI is about as simple as EFI gets so if you understand carburetion you should have no problem with TBI.

Do me a favor - all of you guys who scrap your tbi systems for a carburetor, save them for me. I'll give you $50 bucks for them 

[grinder1989]

Just go buy a carburetor.  No chips, no technology, no problems.  Once you learn how to tune them, they are cake.

No problems? I know how to tune a carburetor but there are plenty of problems. A carburetor will never be able to outperform a computer for versatility and fuel economy. TBI is about as simple as EFI gets so if you understand carburetion you should have no problem with TBI.

Do me a favor - all of you guys who scrap your tbi systems for a carburetor, save them for me. I'll give you $50 bucks for them 

I'll gladly hand them your way.  I do not like TBI at all.  I prefer Vortec spider injectors over the TBI units.  Carbs are easily adjusted and maintainable.  To each his own really.  I do agree with the bold though.

[VileZambonie]

OK-

I'll take them 

CPI's were the most problematic GM ever mass produced

[fitz]

  What happened to "the customer is always right"? 

As the owner of a small used car lot I have to tell you that in todays Lawsuite crazy world you cannot turn a proffit assuming the "customer is always right".