Vacuum Reading from a Vacuum gage should show if you have a valve to tight. Cam being off one tooth can cause a dramtic loss in power. Most of the time when a firing order is wrong the car back fires but every once in a while they just seem like they fight themselfs you may want to double check that also.

Last and I hope least likely. I had a friend that was given the wrong rings by a machine shop. He had really low compression. Even tho it was a 10-1 .030 over it was only hitting 100 PSI on a compression test. Car should have been a monster but it ran like a 305. If you pull the oil cap you would know if that is the case.

 

Valves have been adjusted 3 times. Opti was frI'm summit. Throttle position sensor is new icm new coil new. No codes for miss fire for the motor wouldn't I have that is opti was bad? Knock sensor is just disconnected so far because it wouldnt allow the car to run once unplugged and car car change from cold start it would die car was adjusting timing and it would die. Knock sensor unplugged fixed that. Still getting crankshaft position sensor code p0335 and p0336. Along with O2 codes 140 and 160.

 

when my knock sensor was not plugged in right and got no connection my car ran bad. the computer will go to a set timing that will allow the motor to run but will retard the timing to insure no pre ignition.

 

did you change the crank sensor? if you're getting a code for it, try changing it and see what happens. also, did you tune out ALL your o2 sensors? or just the rear 2? did you put new ones in the front positions? the coating from the headers can cause o2 sensors to go to crap right away. most people allow the car to get to temperature with the old ones still in, then change them afterwards. perhaps that will help out

 

Usual sign of a bad opti is a low res code.

 

Replaced the crank sensor. No avail. Knock sensor plugged in car runs fine in cold start won't run at all after reaching temp. O2 removed. 2 front o2's brand new. Only thing not new is alternator water pump and power steering pump. Everything else brand new except PCM

 

The LT4 uses roller rockers witch make more "knock noise" then the LT1 non-roller rockers.
Also with a high lift cam and springs the valves hit the valve seat much harder "knock noise" and may
cause the PCU to retard the timing also.
REF: HP books on how to rebuild a LT1-LT4 engines.

 

WHEN did you put the new O2's in? if you put them in before you started the car with the new headers, its possible they have been ruined from the coating of the headers

 

Sounds like you might have two parallel problems that are common during a break-in:

• You need to go back through and do a preliminary diagnostic of the engine and forget the dyno readings for now. It seems two things are happening, you are not getting sufficient air/fuel or you do not have sufficient compression. I would first compression check each cylinder to eliminate any internal issues with the piston / ring set up, then check the head setup doing both the valve lash test and then vacuum test for each cylinder, then check the fuel pressure and flow rate of the injectors. You had not mentioned your air delivery, is it still stock? Check the MAF as well. Do all this with the original O2 sensors installed and then test with the new O2s installed.
• I too have had problems with both the MDS and Accell Opti’s failing within hours after installing when I did my ignition upgrade and finally went back to the Delco Opti based on the advice of experienced LT1 users and hadn’t regretted it. I would put a Delco Opti on to eliminate the problem of the Accell one not performing while you are doing your troubleshooting. If the rough idle has not improved, then again check your timing chain / cam set up. The point is to eliminate enough possible causes without having to replace parts or tear into the engine.

 

One Phrase Static Compression is 95 on all cyl and the internal troubles begin sigh.....