Super Old Edit: Problem was not the MAF, it was a bad connection. One of the locking terminals on the ECM for the MAF had broken, and the pin would back away from the ECM randomly, just enough to give random contact, but not enough to notice just by glancing at it. **update update** Well, thanks to a super nice guy (Ryan B) my truck is now deemed "driveable"! Turns out my main problem WAS the MAF. Didn't really want to spend big dollars on one when you can't physically test the MAF (or not without an electrical bench anyways, the manual flow chart said bad MAF, but it was wrong before) and Ryan noticed what I was going through. He PM'd me, offered to sell me his old one (he's now MAP) at a really great price, including his old ECM. I should have just bit the bullet, but for $60-150 (and I couldn't find the $60 one locally, not easily anyways) I really didn't want to. From the shape the box was in that the original MAF was shipped in (with other stuff that was visibly broken) I should have figured the MAF was bad off the bat. Got it tonight, just couldn't wait, threw it in, cleared the code from the ECM, fired it up, and no code! No surging idle, no hesitation, nothing that it was doing while it was throwing the bad MAF code. Let it warm up/think about how it should run itself, and took it for a few spins around the block. If the 465 could be shifted faster, it might even be deemed quick lol. 35MPH in 1st gear, (lots to go, just not safe in this area) and it will bark the tires from about 15MPH. Not bad for a "mild" 350 I figure! Certainly better than my carb, even though that ran good. Front end actually starts to lift under accleration, the old 350 sure didn't do that. Still got some major chip tweaking to do, (still running on a 305 ECM) but I think it just might be ready for the Western US tour we plan on taking at the beginning of August. Will get it insured now, and start doing some test drives locally, eventually putting some serious miles on it to see what crops up after it gets more "broken in". As a side note, anyone else running the comp pro magnum (steel) full roller rockers and/or aftermarket roller lifters? This thing almost sounds like a diesel underhood (not so loud it's audible in the cab) with all the ticking going on. I'd suspect a bad lifter if it weren't equal on both sides of the engine, and sounded a bit different. *old update* If anyone cares, here's an update. No start condition solved. Pays to have a friend helping out...he noticed the remote coil was arcing, and although the service manual test "proved" it was an ECM fault, a junkyard test coil off of a 4.3 Astro (same part) fixed it. Took it out for a spin around the block (no plates on it) and she runs pretty good. Pretty sure I can "feel" the difference of having the computer think it's controlling a 305 though...tends to surge a bit while cruising slowly, and a bit of a "chuggle" when trying to accelerate from a low speed in 2nd gear. Lack of a cold start injector ('87 used, my setup doesn't) is also evident in the amount of crank time to start. The 2 engine revolution delay inherent in the 8 primary injector function on startup is pretty evident, takes a second of cranking (I think the carb started a bit easier) but it is reliable, always fires up after the same amount of cranking. Hot or cold, no difference in how hard it is to start. The new 3 core radiator EASILY keeps the engine cool. (straight water for now) During initial firing it got up to 210* (based on ECM coolant temp sensor readings) but now that the engine is broken in, and the coolant level is up to the top, it sits at 194* (195 t-stat) solidly. Still throwing MAF and EST codes, but I need to clear the codes and see if they come back. Some of the causes of those are likely to be the 305 vs. 350 issue. Combination for anyone following is 355, 1989 TPI setup off of a Camaro, (but 1987 ECM, no VATS) 64CC heads, "flat top" pistons (right around 9.2:1 CR) SDPC TPI base, Mild Crane Roller cam, (.454 max lift, 112* LSA) Comp Pro Magnum Roller rockers, and hedman elite headers. Got a set of Accell "make your own" plug wires, a neccesity IMO with the headers and TPI setup. Going to finish those up tonight. As soon as the codes are cleared, and I get the chip burning equipment, I will start on clearing up the 305/350 differences, lack of cold start injector, and the timing/fueling differences due to the engine setup. Just had to post to say that after all this time, my TPI setup finally ran! Of course, after the initial engine firing (9.2:1 350 w/Vortec heads, Vortec TPI base, Camaro MAF TPI with no cold start injector, Crane Roller cam, Comp Roller Rockers) I had to shut it down because of a spark plug that was leaking compression. (note to self: pull plugs when test-fitting headers, they don't like being bumped) Also decided to fix the brand new radiator that was leaking fairly well because of an errant drill bit (hey, that wood didn't slow down the bit at all!) before firing it back up. Anyways, fix all that, now engine won't fire. /forums/images/graemlins/smile.gif Wasn't nearly as cheerful at the time of course. Needed new battery, got that, need new plug wires, going to make my own because of length and the way I want to route them, after those are in place, try to crank it up one more time, if that doesn't work, troubleshooting time. But I can say that even with one bad cylinder, it settled into a fairly smooth idle no problem, and throttle response once off of idle was fairly impressive, no lag whatsoever, and this ECM is off of a 1987 305. /forums/images/graemlins/smile.gif Really going to be interesting to see how she runs with all 8 cylinders working correctly. After I get it running again, going to start burning PROM's until it's running as good as possible. With the Vortec heads, bigger cam, and 350 instead of 305, there should be plenty of performance to be gained from PROM mods. Pics here of random stages of the engine build/install, have to take some more once I get the wiring all tidied up. random TPI pics Don't be surprised if the site gets locked down, they don't allow much bandwidth for free. It comes back up in a day. Oh, and the picture of the engine that has "EVIL" on it is in reference to exhaust manifolds, not how bad I think the engine is lol. Oh, and I can't let anyone think that I acually used zipties to hold the fuel lines in place...those were used for mockup until I could find metal to make the brackets shown in some of the other pictures.