I have been playing around with my tune and learning how the stock BCS works. I did a few logs today using Evoscan. I'd like to get some feedback, especially regarding the boost taper I am seeing.

Mods: EvoIX
Buschur 3" TBE/HFC/Billit Muffler
Works panel drop in filter
JDM Map Sensor (logging boost only, no direct boost control)
100% stock BCS


I have my ECUFLash setting MWGDC to 127.5 at each RPM point, and the TBEC table is zeroed out. BCLO is set at 80 and BDEL is 159.4 at each RPM point, so I'm shooting for 240ish load across the board. Basically I wanted to see what the stock BCS boost curve looks like with WGDC maxed out at all times. Temperature was 72F and the runs were made in 3rd gear.

Is the boost curve shown in the logs typical for this situation? It seems to peak at just under 19psi around 3400rpm and taper to just under 14psi by 7500rpm. I understand the boost restrictor pills etc. are going to limit boost to around 20psi anyway, but is dropping to 14psi by 7500 normal?

 

can you provide neccessary data like TPS, wideband A/F... and group them together (all those columns next to each other) so that it's easy for us to read the log.

 

+1

-E

 

With a 100% stock system with the stock pills, yes.

 

Well the TPS was 100% for the entire run because my foot was on the floorboard. I do not have a wideband... yet. My main concern is the boost curve for the purposes of this post.

 

Thanks razorlab!

I'm wanting to shoot for as flat a boost curve as I can with a target of no more than 20psi. Should I ditch the restrictor pill on the solenoid line, tune my BWGDC as needed, and go back to using the BDEL/TBEC tables to smooth it out? I want to play a little without changing things too drastically. I plan on adding a WB so my AFRs don't get me in trouble. Trying to crawl before I walk here.

 

One thing I don't understand is how my boost readings can stay in a close range for a certain RPM (for example in the 3500-4000rpm range it's around 18psi measured on the JDM MAP) while the 2-byte measured load varies greatly (200-227ish and the JDM MAP reads in the range of 18psi).

Also, my load error is always 19.8 and the math doesn't work (desired 240 vs. 2-byte measued). What am I missing there?

 

Well after doing more research it looks like I could get the GST Motorsports Boost Pill Assembly and level out my boost.

razorlab-

How is the taper at redline using that setup? I see it allows around 26 psi of boost, which is way over what I want. I just want to level it out as much as possible at 20psi.