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knock after engine rebuild..

Posted: Mon Jul 11, 2011 3:01 am
by contectr
After my engine build (9:1Rc) i have 5-6 knock at 4300-4500 rpm at 14.7 psi of boost.

Before the engine build with stock engine (11:0 Rc) at the same pressure of boost and same ignition-afr kalibration i don't have any knock.

The afr is pretty flat at 11.8-12 with my plx wideband controller...


Yesterday night i have try to retard the ignition in the Knock zone at about -3° and it's knock the same.
i have try with premium fuel (100 Ron) and it's knock same..

After this i have try to reduce the boost pressure with the boost control at 12.9 psi-11.4 psi and at 7.1 psi (wastegate spring) and the knock are the same. Only with 7.1 psi sometimes knock ant sometimes no knock..

The build is:
- Wiseco 86.5 pistons rc 9:1
- Pauter Rods
- Honda Oem main bearing
- Honda Oem rods bearing
- new chamshaft chain
- new oil pump Honda Oem
- GT3582r Twinscroll tubolar manifold setup with 2 38mm TiAl wastegate

I have a little pistons slap at cold engine at low rpm (low than 1250 rpm) but when the engine is hot all run perfect without any noise..

It's possible the knock are false because with forged internals the engine is a little noise than stock?

I attach the datalog with the Knock..

Re: knock after engine rebuild..

Posted: Mon Jul 11, 2011 9:59 am
by Spunkster
With forged pistons it may just be engine noise that is reading as knock.

Re: knock after engine rebuild..

Posted: Mon Jul 11, 2011 4:03 pm
by contectr
Ok Spunkster..I had the same thought
The solution is to reduce the sensitivity of the knock with the release 1.5.1 Kmanager?
I could see from the tables of the knock that the sensitivity is very high in the area between 4000 and 5000 rpm in the calibration Honda.

Re: knock after engine rebuild..

Posted: Thu Jul 14, 2011 12:56 am
by contectr
Last night i have try to reduce the IGN at 10 ° for 14.7 psi of boost..
See the datalog,..