i have recently built a y5 block and z6 head with the new style fj I-beams. i have put it together and it runs but when cold it idles real low, which i am assuming is because the coolant lines that are going through the throttle body are not hooked up, but my main concern is that it will idle and idle and idle and i can rev the motor sitting still..... BUT when i go to take off it has absolutely NO power AT ALL. i can be @ full throttle and nothing. it pops back through the intake which i have already checked the timing tons of times i have tore down and bolted the head back multiple times, being i had compression issues because the machine shop didn't do my head correctly and i had to trace the problem down. but i am now @ like 115-125 psi of compression on all cylinders. the motor only has like 2-4 hrs of runtime on it. but me and my buddies are both kind of out of ideas at the moment so any constructive help would be greatly appreciative.

 

well come to find out i retimed and readjusted the valves to be sure again and it did the same thing.......... THEN my buddy said try a different ecu and it worked and i drove it home so the map on the s300 is kinda wrong i guess but thats just the last thing that was wrong i had other events that caused some issues as well but at least the problem is solved for now, thanks everyone for the help

 

ok just let it break-in then push it to be safe

 

...get a real tune.

and its a D.