aight, I droped my motor in and tuned a lot, got really close to 128's for BLM's first 100 miles of breakin in period and kept driveing, real good gas mileage, nice responce for not getting on it ... now I try to get on it and it just bogs down massivly and does not accelerate at all. This was a rebuild, nothing changed really, just some head work and grinding of the crank... every thing elce is same as last time, cept new wire and plugs ect. Why would it run so perfect with great manners untill I get on it? Timeing? Did I forget to change something in the chip? What gives?

 

It could be several things, it could be pump shot, or timing, or the main VE tables may be off at WOT. Do you regester any knock counts in the 90+ Kpa cells?

 

You'll need to datalog and scrutinize the results. You should be able to identify the problem reviewing the info, or at least a few tell tales of a mechanical malfunction.

 

Dewey, yeah plenty of knock up high and some around the 90 kpa cells... I droped the spark way down around all the cells where I was getting tons of spark knock, still no better, I went even as far as unhooking the knock sensor momentarly just to see if it was retarding the timing a little to much, no change. The only thing I found that helped at all was when I pumped the BPW constant way up, even though it made the engine extreamly rich again it reved a little better, but not much. I have taken tables constants and things I have never played with before from one extream to the other and gotten the same exact results, zip! I even notticed that nothing changed at all when the ECM was in limp home mode (dummy me turned on my laptop with it hooked to my prominator which eraces the bin) just the idle was a bit more ruff... I can't really imigine it is anything mechanical, everything on that engine came of the running fine 305 that got pulled earlier the same day. I even tried the bin that ran this same exact motor in my other camaro, only thing that changed was now it has an IAC, ran the same way. No error codes, no excessive heat, no leakes, no pings knocks or other weird noises, just massive bog at WOT with or without PE.

 

have you redone your timine? If over richening it helped it bit, you may be masking the knock with all the fuel. It should like you have issues with the spark advance, that would also explain the bad idle. I would also check it for vacume leaks. it may be a leak messing with your stuff, one way I check for leaks, is to look at the IAC steps at idle, if the IAC is closing itself trying to meter things down, that will indicate a leak, you might also try unplugging the IAC, and manualy setting the idle to about 450-500 rpm, but before you do that, you need to make sure you have no leaks.