I would like to know if anyone has put one together has any advice because its kind of a dog (Iam quite pissed off actually) it doesnt have the power that it should it feels more like a ran down 2.8 I was told by some that the computer needs to recalibrate itself which suposedly could take 1000 or more miles. any feedback is appreciated.

From what I have learned about GM computers, they do very little learning and a lot of "compensating"- deviations from the prom info to compensate for incoming data. I would try to adjust the timing and see if the performance changes-for now, disregard the timing mark and move the timing up a little at a time.

I'm hoping that people with a new engine adhere to a break-in routine. It does sometimes takes a few easy miles to seat the rings. Checking the timing was suggested and is a common problem with new engines. Rocker arms being poorly adjusted is another commonly overlooked problem. What kind of head work was done? The valves and seat were ground at least, right?

im not sure, but a while back, a member did a 3.1 and said it kept gaining horsepower up until 500 miles i think. he said it felt like 5 hp every 50-100 miles. once again not sure of any of this, but i do beleive the thread invovled him killing a mustang, then we got this angry mustang flamer....

put a chip in to help the process along...

Any fresh rebuild need time to work in. You should also change the oil after the first 500-1000 miles.

At the very least I put in magnetic oil plugs in rebuilds, heads, etc. Better yet I put a large magnet from and old computer disk drive in the oil pan. The big ones from old 5.25 floppy drive will catch junk for years. The small "rare earth" jobs from hard drives are good too. Just leave them in there till the next time the pan comes off. They will collect huge ammounts of trash before they get "worn out". even them they will never release any of it back into the motor.

The heads were not milled but they were ported along with a valve job GM performance springs (fierostore) new vavle guides and 1.6 ratio roller tips, crane cams. The timing is right at 10 degrees with diagnostic ground and the rockers are relieved of lash.

The ECM should learn each of the block cells within about 20 miles assuming you've gone through each of the conditions (MAP vs RPM).
You need to let it idle, use soft, moderate and high throttle, low and medium RPM's so it can learn the closed loop setting. WOT don't matter since it isn't closed loop.

Yeah, I'd give it until 5000 miles before I decided that something was wrong with the power. Depending on the rings you used (moly are a long wait), it will take some hours to seal them up.

Did you put in a new fuel pressure regulator? Usually a 3.1 upgrade requires more fuel. You can get this by installing larger injectors (like the ones in a small block Chevy) or you can put an adjustable fuel pressure regulator and jack up the pressure a little. Ed Parks (Fiero Factory ((256) 420-5391))could tell you the pressure to look for. Otherwise the engine will starve for fuel and run like a work out 2.8.

Good luck,
Carroll

Ogre,

Are you talking about the read/write head magnet off a hard drive? Do you just drop it in the pan or do you glue it down with something? My dad has tons of crashed or otherwise not working hard drives laying around...

thanks

I noticed the topic review is on the same page now! very cool!

[This message has been edited by Standard (edited 12-01-1999).]

epoxy the magnet in the oil pan.
another good thing to do is to epoxy small
magnets in the heads and lifter valley to
keep valve train trash out of the oil pan.

Don't jump up and increase the fuel pressure. Find someone with a scanner and check the O2 voltage. If it is over .800V to .850V at wide open throttle, adding more fuel will only slow the engine down.

An increase from 2.8L to 3.1L is not that cosmic.

I'll bet it's at least .800V.

The fuel pressure (which can be checked with an A/C gauge set.) Should be at least 39PSI with 45 PSI being optimal for the stock injectors.

Some engines do need more fuel, but rarely is this the case for just a 3.1L displacement change. GM runs too much fuel as it is to cool the cylinders down.

I'm leaving the fuel pressure reg. out for now because I want to see if I really need it (Summit hasn't sent it yet either). If there is a need for more fuel won't the computer automatically richen the mixture? I want all the power I can get, but I'm not sold on pumping a bunch of extra gas into the engine.

Are you sure it was timed properly? I mean, did you use piece of wire or something to jumper the terminals on the ASDL??