Car - AE86

motor / part in question - Fresh smallport 4AGE

problem - frustrating scary noise

occurs/started when - Fresh rebuilt smallport with new rings & bearings and everything blue printed and honed etc. The motor then unfortunately sat around for a couple years dry (no oil or coolant) before anything happened. It was turned by hand now and then, and eventually when progress was made - run in oil was filled and the motor turned over by hand quite a lot, and then on the key without ignition and eventually when the microtech install was completed - she fired up. Unfortunately we were faced with this noise which inconsistently got better or worse without pattern irrespective of RPM or anything - it just came and went.

Now.... Oil pressure sensors (like all of the microtech sensors on the motor) are showing adequate pressure and everything operational/flowing and seemed to be perfectly fine. However. The scary noise gremlin is hangin around...

Is theoried to be something to do with shims and the valving maybe? Or perhaps a manifold leak? I havnt pulled plug wires off to see if it goes away with a cylinder; someone suggested that the noise sounds bottom endy mainly due to the speed? The suggestions that have been made to me i havnt checked yet as im hesitant to start the motor again until I get it looked at. Im no mechanic unfortunately but the engine builder & handy mate of mine is. The car goes in for exhaust weld up and a dyno run in and dyno tune in the next week or two - but if we can throw ideas around and possibly trial and error eliminate potential issues before the car goes in to their workshop it may save some dramas and stress for my mate.

I have attached a link of the running of the motor - unfortunately the upload i made to youtube is of lower quality than the original and the second half of the video theres a second noise that happened but is hard to listen to on this upload.



Thanks in advance everyone