I've posted recently about having removed my BCS line pill. After doing this (only other mod my car has is a Jestr M1 EFlash) I was seeing knock as high as 9 when logging with EvoScan. I have added fuel and reduced boost (via Max WG Duty) and after logging tonight here's what I've got...



My question is, should I be satisfied with this level of knock? I've searched and the consensus tends to be that less than 3 is pretty normal. But should I keep adding fuel/pulling timing/lowering boost to try and get to 0 knock? Will I ever get there?

Thanks for your input guys!

 

You need to do proper logging. One log is not enough to tell you about knock. You need to do at least 3 back-to-back logs and see if there is consistent and increasing knock in the same rpm areas.

If after doing 3 logs you get the same 1-2 counts that you are getting now, then I would not worry about it.

Another thing you must do when you log is have the log start @ 2500-2700 rpm and end @ 7500 rpm. Your current log is too short.

 

+1 looks fine to me.... if it knocks more then add some fuel.. timing looks fine, dropping the boost isn't needed since its very minor knock

 

under 3 is normal, but if its really cool where u are right now. when the weather gets much warmer you may find it knocking higher..

 

Thanks for the feedback...

I have done at least 10-15 3rd and 4th gear runs. Sometimes I've started lower and sometimes I've started like the log you see above. With this tune I've never seen any more knock than what you see here. So the log that I posted is what I'm seeing consistently.

I plan on installing a full 3" TBE with race pipe, and then of course the weather will get warmer. So I these things change I will continue to log and may have to add some more fuel back in to keep things safe and happy.

Thanks again everyone for your feedback!

EDIT:

I just did some more logging, if I'm seeing calculated load values of 240-250, can anyone tell me what that approximates to in boost?



EDIT2:

I found this post in another thread...

So if I'm seeing 250-252 peak and then tapering down to 240-230 that means I'm approx. peaking at 1.5-1.6 bar (or about 23 psi) and tapering down to 1.4 (about 20 psi). I realize that basing boost on what load cell you're in isn't exact. But it gives me an idea until I get my JDM MAP sensor.

 

Calculated load reads roughly 10% higher than real load. Boost is usually a 2-7% less then real load divided by 10. So, if you are seeing a calculated load of 250-260, that's more like a real load of 225-235, and a boost level of around 21.5-22.5 psi.

Like nj1266 said, it would be a good idea to start your logging run at 2000-2500 rpm, and end somewhere between 7000-7500 rpm. Its also a good idea to get some logs of slamming the throttle to the floor at various rpms (say from 3000-5000) to see whether the boost spikes are under control.

 

Thanks 'mrfred'... I plan on continuing to log to make sure knock stays in check as I add things like my TBE.

Because I'm not really a 1/4 mile guy and more of a road course guy I want to make sure that the tune can stand up to prolonged full throttle running without developing any knock.

I'll definitely do some more logging runs with stabbing the throttle and also rolling on at as low a RPM as practical (like ~2500 RPM).

Thanks everyone for your great feedback!

 

I read somewhere that some DPs that run to near the cross bar or Trans can cause a tapping or knocking under acceleration. Can that be read via the KNOCK Sensor?

 

UPDATE:

Here's a full 3rd gear pull I did from ~2500 RPM to red line...



(Sorry for the small print, but wanted to get the whole pull in a reasonable size image)

Knock looks really good. However, in the same log I noticed that when I was pulling on to the highway I did see a random 4 knock sum show up. But this run seems to make things look OK.

I might see if I can narrow things down a little bit and add a little fuel yet.

 

I think the problem is the poor rpm signal from the open port. The signal is very steppy and that makes the Calc load inaccurate. I log my rpm with the innovate LMA-2 as well as the the one from the open port and I do the load by airflow formula on both and the difference between the two is about 20 points. The LMA-2 rpm signal is much faster than the one from the open port. Since my airflow does not clip, it does work for me.

I applied your 2-7%/10 boost formula to the load by airflow that I calculate from the LMA-2 and it was very close to the actual boost that I log with the MAP sensor. The peak load was 228.4-16/10=21.2. The actual peak boost was 20.91.