Hello, I am new to this site and had a question on my new 08 screaming eagle ultra. Is spark knock a common problem under heavy acceleration? I run 94 octane or better, but do I stil need a booster? Any replies would be appreciated, Thanks.

 

If you're running 94 already, I would be looking into piston slap more than detonation problems. Knock sensing should take the ping out if working. There is a possibility you could be excessively lean as well, maybe from a leaking intake seal. It should run fine on 91 if all is well.
Ron

 

a knock is like having some one hit the top of your pistons with a hammer, not good. also might want to check your timing.

 

Did you have the Campaign done? Check this thread

https://www.hdforums.com/forum/screa...vo-recall.html

also check Here http://www.cvoharley.com/smf/index.p...ic=25324.0;all