318 wont rev above 5,300

I have a quick question


I put a turbo on my 318 and used the summit cam SUM-6901

I am having issues with the car running above 5,300 - it breaks up.

I was wondering if anyone had an Idea. I have tried a different coil, but maybe its a broken valve spring. Could the cam keep it from reving above a certain RPM?

THe car runs great up to then. It ran a 12.32 @ 105 short shifting at 5,000 and the car has 3.91 gears so it needs to go through the traps at 6,000. Its puking at the finish line.

Should I get a bigger cam? or do you think its electrical? Im running an MSD and a boost controller.

Thanks for your insight!