Hello everyone,

Monday i installed my GSC S2's cams together with the Kiggly beehive springs.
(Car is otherwise stock except for the S2's and an exhaust).
I started by taking 3 degrees out of the entire timing map, and richened up the whole spool to top-end area by a 1%.
When i logged the car it has 36 counts of knock once above 2500 rpm.
Eventually i got the point i have taken over 10 degrees of timing out, and it's still knocking like crazy.
GSC suggested the cam sensor plate is flipped 180 degrees, i checked timing on that and it's in the correct position. I tried flipping it 180 degrees just to see what happens, but that made it so much worse.

Any tips on what i could try next?



Attached the log.

 

The most common reason for part throttle knock after changing cams is all the extra mechanical noise triggering the stock knock sensor settings. Let's go through the easy stuff first. Do you have noisy lifters? Did you bleed all your lifters during the cam switch? If not pull the cams and bleed them all.

The next most common reason is mechanical noise from valve spring coil bind, or retainers hitting the valve seals due to the extra lift of the S2s. Did you check if the Kiggly beehives, spring seats and retainers you are using actually work with the S2's without interference?

Once you have all the basic mechanical stuff worked out then move on to tuning. S2's are pretty aggressive with a high ramp angle which changes overlap significantly. This affects VE during spool requiring ignition timing reductions from stock and added fuel. S2's on the Evo 9 will need MIVEC table changes to reduce overlap during spool to control part throttle knock. You may also end up having to reduce the stock knock multipliers and filters to reduce false knock counts. This means you will need det cans to detect real knock during spool before deadening the filters. Be prepared to throw some 110 octane in the tank to make sure the knock is real!

Take it easy, use small steps and you will get there.

Looking at your logs - you must start by getting your injectors dialed in at idle and cruise. Read Merlin's guide if you don't know how to do this. Your LT low trims are pegged at +12.5 and your O2 is calling for more on idle. This means your injector latencies are not set correctly for your new cams, the fuel you are running (you don't say what it is), and/or your injectors may be clogged. Your mid range AFR is too lean on throttle tip-in, and this may also be contributing to the knock. It is impossible to tell though because you are not logging boost pressure or MAF Hz so we can't really see what's happening during spool up. Get a 3 bar MAP sensor wired up to your ECU so you can log boost pressure, and log MAF Hz.

There are some other missing facts if you want help from the community to diagnose the knock:
Evo 8 or 9?
What ROM are you running?
What fuel are you running?
What fuel system?
What plugs and gap?
If Evo 9, what are your MIVEC advance settings?

 

Thank you for your reply CDrink,

I did clean bleed the lifter prior to installation.
I am actually using the Kiggly HP-SS Beehive kit. - https://stmtuned.com/collections/mit...lve-spring-kit
From what i've read this kit is compatible with the S2's. A kid here locally runs S3's on them.

They are the stock old injectors, i think they have never been cleaned. Might aswel throw in some new injectors then (i have a set of RC 1200's).
Since this is a UK evo, it does not come with a MAP sensor, the port in the intake manifold is actually never drilled out. I will see what i can do to install a MAP sensor.

It's a 2005 Evo 8, UK Spec.
It's the original ROM that came with it (96530006)
Completely stock fuel system, including the OEM pump that came with the car 17 years ago running 93 (since that's all we have here).
If i remember correctly i used the NGK BPR7ES at the gap it came with.

Thank you again for this very nice response

 

Bump , I’m about to install these cams with kelford value spring & lifers

@CDrinkH2O

if you could please tell me step by step guide would be awesome and help me'¡ how to reflash or custom tune it would help!

 

The best place to start learning how to tune is to read Merlin's Tuning Guide.
There is also a good series of 16 tutorials on YouTube -
Start there and ask questions as you go by posting in the Lancer Evo 1-9 Forums > Evo Engine Management / Tuning Forums. All the information you need is here, and there are many people who can help you.

 

Another great guide would be evans performance academy, I paid for a months subscription and I learned how to fully tune my evo within 2 weeks.