Hey guys, i have just recently finished building an lsvtec high comp motor a few months ago and am at over 1500 miles, ive been to the track with it 3 times and posted times at 15.0 first time then 14.4 the second and with some cam and dizzy timing at the dyno i hit a 13.9 yesterday, now my problem started yesterday when i tryed to hit a 13.8 before i got caught for not having a helmet i hit first and second no problems as usual hit 3rd shifted great as it was going through the rpm i head a ding sound so i let off hit a 14.6, i pulled into the lot and opened the hood to find the motor misfiring but after a quick look i found that the plug to the dizzy popped off, i put it back on and after 10 minutes and a few engine on and quick offs it cranked over and stayed running as usual, i said lets try again and my girl says we better have a ride home, so same thing through 1st to 3rd and then at 7500 it stops giving power i kept on it and in 4th it was the same thing so i stopped im thinking it mite be valve float im running itr cams with itr valve springs on the intake side and b16 valve springs on the exhaust side any clue as to what the power loss would be

 

update just found out that im actually running type r valve springs on both sides sorry for the misquote

 

had the builder take it for a drive he thinks it might be an issue with the cat causeing a back fire, which explains why the plug popped off and also the sudden loss of power at a decently high rpm, but if anyone has info on what else it could be it would be much appreciated

 

im going to through in a omni power straight pipe and see how that works out but im off to training for the next two weeks so ill let you guys know how it acts after in case anyone else is haveing a problem like this