Tuner Nerd + EGT vs Plex Knock Monitor

Hello All, I am having a conundrum and am on a tight budget. First of all, I am not a pro tuner. I am just starting to learn to tune my JDM EJ207. Since this is a rebuilt engine with increased bore and stroked size, I am not sure the OEM knock sensor is good enough for the factory ECU.

I can see two options to make sure my engine doesn't blow.

First, I can buy an EGT to monitor the hottest/leanest cylinder #3 and use the tuner nerd to monitor knock, but I won't know which cylinder will knock.

Secondly, I can buy the Plex V2 or V3, and I can see knocks for an individual cylinder.

I appreciate your professional opinion on this.

How much has the bore changed?

I went with JE Ultra 92.5 mm piston.

A 0.5mm bore size change will not effect the knock frequency enough that the OEM ECU will not work.

not sure if its just my setup or other peoples as well - but there seems to be a 0.5sec lag between a knock event and the tuner nerd displaying it on screen or passing the audio to your headphones - it does detect it - but in that 0.5 second "bad things" could happen in a stressed engine situation....

There shouldn't be any lag between the event occurring and the reporting of it. The knock sensor is a piezo crystal stack that generates a small electrical charge based on the force applied to it, the greater to force, the bigger the voltage spike that occurs. The knock detection device in use then amplifies this signal into a usable voltage and displays the value in the require format. If there is lag during this, it would most likely be in the amplifier system.

Maybe it has something to do with how Windows processes the audio signal. Windows is known to add a lot of lag to audio input, especially in Windows 7 and earlier.

The Difference Between the ASIO, WDM and MME Drivers | Sweetwater

I totally blame windows for the lag i experience :)

looks like it runs in java so theres the (audio capture / processing / output) loop - plus windows OS lag - that it has to deal with - and im not able to run my desktop in the car when im road tuning so i dunno how much the old laptop i have adds to any lag as well :)

the audio you hear is post processing and not a direct feed through a hardware circuit from the sensor to headphones, so it goes through windows and its seeing not a full hardware solution like the plex or link one's ive seen - it has a few downsides.

...on the plus side tho :)

it gets updated quite a bit, and its possible to give the software much more features than it currently has, so its not all bad :) Its got a built in dyno type graph for screenshotting for your friends lol and it has some very nice gui stuff that makes it easy to play with and interpret the data, and the dev has been tweaking the filtering code etc a bit since i last used it.... but I pulled it all out when i installed the factory honda knock sensor again and removed the donut one to let me easily swap between the haltech and the factory setup if i want to rip data from the factory ecu. Itll go back in again sometime when i look at fiddling with more timing, but mounted to a different point from the factory sensor location.

overall - for me - I'm pretty dang happy with it tho.

its much better than nothing and you can replay logs as well - in raw or filtered form, so its good for me doing road tuning - and im not going to get every last degree of timing available with my hobby fiddling :)