[hatzie]

Originally Posted by Chrispbrown36

87 4wd with a 350 TBI and 700R4 tranny. The motor is not the original according to the guy I bought it from but he didn't say what it came out of, how many miles on it, or anything else that might have been useful. I was too blinded by the beauty of the truck to think at the time....let's call it truck goggles.
The O2 sensor is about a year old and I believe it is a house brand from somewhere. I have been trying to stick with AC Delco on everything, but that one I slipped up on. That will probably be remedied soon.
The TPS, idle air control valve, and map sensor are all new (past year to six months) and AC Delco.
Not getting any vacuum leaks at the throttle body base. The EGR was leaking on me but has been replaced....but I went with an off brand locally instead of waiting on an AC Delco to be delivered. I do have a vacuum leak toward the back of the intake manifold, so I am going to redo the intake gaskets in the next couple of weeks.
No slop in the bushings either that I can tell.
.....So the love affair with the truck goes on but the engine and I are barely on speaking terms!

If you can read the block casting number and stamped engine codes on the RH block pad you have a shot at figuring out what the engine was when it left the factory. The early TBI systems needed to be programmed to match mods like cams etc. but you should be able to get away with slight changes.
If you can find out what CAM, heads, and pistons you have you can probably find a tuned EEPROM image for that setup.

You want to keep the TBI setup or move to MPFI if you can. Carbs are easier but don't extract the power that a properly setup EFI system can. Stock 1987 the L05 TBI 350 had 35 HP and 25 ft-lb on the Stock Carbureted 1986 LS9 350. The 1987 L03 TBI 305 had 10HP and 25ft-lb on the Carbureted 1986 LE9 305. The TBI system did this with better fuel mileage and without blowing out huge amounts of garbage from the tailpipe.


USB ALDL interface cables are not expensive... $55 at most and you can build your own for less. Used enterprise class XP laptops are right around $100. WinALDL and TunerProRT are not difficult to use and are either free or donationware.
You start running into real money when you get an emulator like the Ostrich and start building your own custom programs. http://support.moates.net/gm-86-95-obd1-guide-read-me/