427 mustang drag car. Number 4 cyl lost power. Had on dyno for 7 hrs. Problem not solved. All cylinders at 60 comp. have done leak down 2 percent ea cyl. 5 per cent allowable. Fairly new engine.smoked engine. No leaks detected.brand new injectors.bench flowed perfect. Replaced 5 plugs this cylinder. Replaced new coil, and wires.camera in intake shows injector spraying perfect.has Morris cam. States cam cannot overlap to cause this problem. This is a blower motor produces 190 comp per cylinder. Took all wires from cylinders except number 4 . This cyl barely fires.engine burns race fuel only.engine screamed on old heads. Old heads leaked. Replaced with trick flow heads. Engine has bombed ever since. Help needed,if you can.
I wonder if the cam is ground wrong or something else goofy that’s not readily obvious at first glance. I’d probably go back and check some basics. You can have good compression, no leakdown, good ignition but if it’s not mechanically timed right, it’ll fall on its face. Any way to get it timed for Cyl1 and then manuallly rotate to check if Cyl4 is in proper mechanical valve timing and ignition position? Is the cam phasing right intake to exhaust? It’s a stretch but seems like you’ve tried most everything else. Something is not lined up right, the injector or ignition timing is wrong. Just one cylinder I keep coming back to the cam…
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