BNR S3 Slow Spool and Low Max Boost

[qkrthnu2]

I've been struggling to hit my boost targets with my BNR S3.
I'm currently targeting 20psi (3 Bar Map sensor is on the way)

Here's what I've done recently:

- Stock EBCS I was hitting 20psi until about 4500rpm then trailing off down to 15psi.
- Installed a Grimmspeed 3 port EBCS, initally in bleed mode just like stock. That held a little better, but not much.
- Installed Guardian Angel, tested and is now set at ~21psi.
- Switched Grimmspeed over to Interrupt mode
- Removed the restrictor pill I had been using

Spool is slow, e.g. I stomp it @ 3k and I don't hit 20psi unti 4200RPM.
20psi can be held until 5k, then it starts dropping off down to ~18psi above 6k

With the compressor connected directly to the wastegate it looks like spring pressure is only ~9psi. Is this adjustable?

I'm not sure if it's the wastegate, my stock CBE, or something else that is keeping me from hitting targets.

Just to show how bad it is I've attached a log where the boost source line popped off the EBCS (uncontrolled boost situation ) and I still wasn't hitting high RPM targets. You'll see where the line popped off because WGDC drops to zero with no effect.

[qkrthnu2]

I'm thinking it's just my Corksport SRI and stock cat-back that is limiting flow.

Does that make sense with the flow rates I'm seeing, or am I not flowing enough for that to be the problem?

[aaronc7]

SRI or catback shouldnt limit your boost by any meaningful amount. I suspect wastegate/boost control here but don't have any specific advice for you since I have been out of the Mazda game for awhile. I bet if you remove the vacuum line completely to the wastegate she will make plenty of boost...... gotta be a boost control solenoid/wastegate/tuning issue.

[Code Monkey]

How long have you been running the BNR?

When my BNR took its time to boost, my primary cat was gone and clogged. But even then, once in boost, it would hold 21 psi until redline so you have an extra issue to solve.

[Kor3y101]

Here's a link to someone who had a similar issue ; My experience installing and tuning BNR stage 3
They adjusted the preload (wastegate actuator) and changed the restricter pill (which granted, isn't relevant to you with a 3 port) But have you tried changing the preload?

[Easter Bunny]

Some people have also had air leaks at the turbo housing.

Check for boost leaks.

[MD1032]

It's gotta be something with the WGA not closing fully, or opening too easily for some reason (failure), right? Gotta remove the top of the downpipe and make sure the flapper is closed and the WG is working properly.

[qkrthnu2]

Which 2871 compressor map (Google images search) matches the BNR S3 the closest? The various 2871 maps are vastly different. I figure I could rule out a boost leak by comparing MAF g/s to what the turbo should be moving.

No vacuum leaks for sure.

I'll definitely try adjusting the preload on the WGA, anyone have experience doing that? i.e. Two turns tighter would have how much of an expected effect? It's a fair bit of work to do a lot of trial an error, so I'd like to get it close to correct the first time.

[CFI2008]

Check your fuel trims for boost leaks. There was a thread on here about adjusting he bnr preload with a how to. If I recall 1 full turn is 1 psi adjustment.

[qkrthnu2]

What's the typical range of adjustability?

My trims are all pretty close to rock solid < 2

[CFI2008]

BNR Stage 3 WGA adjustment

[qkrthnu2]

Thanks CFI2008! That's an awesome thread, just what I needed.

[qkrthnu2]

Just checked my turbo. Hard to see with the heat shields in the way, but it looked like there was quite a bit of room for more preload. Went back to the pics from the install and....

[qkrthnu2]

Since I'm only seeing 9psi for spring pressure and I have the Guardian Angel in place, I think I'll pull the WGA and tighten it 4 turns.

This looks like it'll take more time than I want to spend this weekend, and I may as well wait for my 3 Bar MAP sensor to get here, so I probably won't get to this until next weekend.

[qkrthnu2]

Wish me luck.

[Mike@Stratified]

Before you go making pre-load adjustments, 3rd gear, in those temps from the first log, with your small intake, the turbo is going to struggle to spool up. I would try a 4th gear log starting at 3k and post that up. If you give too much pre-load you are going to fight boost spikes.

[qkrthnu2]

Everything is apart, so it's getting adjusted LOL. I have a bunch of 4th gear logs, same results. I'm planning on moving to a 3" intake before too long, or should I go 3.5"? I'm thinking 3" will be fine since that would be significantly larger than the BNR inlet already.

[Mike@Stratified]

3" should be plenty.

[aaronc7]

That's what she said

[Easter Bunny]

Originally Posted by aaronc7 That's what she said

She was being nice to you.

[JgamB]

Who is tuning the car? These WGDC values / responses don't look like anything I've ever seen, plummeting from 80% to zero in 1 second and then trying to recover to 100% just as quickly. That CHRA is probably just losing too much inertia to do what is being asked of it. These timing values look incredibly low, 4° from 3.9K all the way to 5.5K without knock.

Something is fucky.

[qkrthnu2]

Originally Posted by JgamB Who is tuning the car? These WGDC values / responses don't look like anything I've ever seen, plummeting from 80% to zero in 1 second and then trying to recover to 100% just as quickly. That CHRA is probably just losing too much inertia to do what is being asked of it. These timing values look incredibly low, 4° from 3.9K all the way to 5.5K without knock. Something is fucky.

I'm tuning it. The EBCS boost source hose blew off in that log, and I was slightly over target so the computer was trying to bring it down but there's nothing it could do with the hose popped off.

My boost error ramp is higher than the OTS maps so that's how it moved so quickly.

[JgamB]

How about a clean log - and I've never seen a base map with spark advance dialed back that far at 5.5K. I'm a bit concerned you might be really heating up the exhaust valves and it might've contributed to your knock.

[ms6mil]

Or post the map.

[qkrthnu2]

Since I've been dealing with boost issues I haven't begun to tune timing, so yeah it is really low right now.

Got the car all back together, didn't lose the clip!
Installed a 3 Bar MAP sensor and swapped out brake rotors today too.
And I just ordered a HTP 3" intake from @EdgeAutosport.com!

Zero'd out my base WGDC table, made the MAP scalar adjustments and took it for a spin. My Boost error ramp hit its max at 20, so it wasn't quite zero'd out, but still looks like a good result from the preload adjustment. 4 turns tighter and spring pressure is now 13-14ish.

Short log attached. I'll get the boost dialed in tomorrow so that I can finally start tuning timing.

[JgamB]

Looks a whole lot more logical now. That 2.1 KR lift throttle knock might be a good idea to look for loose shit on your RMM / FMM.

[ms6mil]

Still interested in the map.

[cshunter]

Originally Posted by ms6mil Still interested in the map.

^ This brownie......









































































































Post your shit up, he is helpful regardless of color.

[qkrthnu2]

Originally Posted by cshunter ^ This brownie...... Post your shit up, he is helpful regardless of color.

I wasn't ignoring him, some of my best friends are brownies, I swear.

Not sure why y'all want to see my fugly azz map, it needs A LOT of work still. Timing is flat up top while sorting out boost. WGDC is flat since I'm basically starting over after adjusting WG preload, so basically not much to see. Here it is, laugh away.

I showed mine now show me yours.

[qkrthnu2]

Well, it's holding boost above 5k now , but it's still taking more WGDC than I was hoping for, and spool hasn't really improved much.

I'm hoping the 3" intake will help.

[JgamB]

No one wanted to laugh at your map - we just want to make sure you don't blow up your car. I'll take a look after the UFC fights tonight.

And I've seen a BNR S3 tuned on a 68mm intake, that isn't your primary issue.

[qkrthnu2]

I apologize for getting defensive. I just know my current map is going to get heavily criticized, and rightly so, it's no where near finished or close to anything someone would want to run. I definitely appreciate any help!

Here's a good example of the intermittent KR I'm seeing, which is why I initially reduced timing to 4 degrees up top while tuning boost, although it doesn't seem to have helped, so I guess I should just go back to something closer to OTS values.

These are back to back logs (and the map I was running at the time).

The first is an uphill on-ramp 3rd gear, nasty KR. Next is a downhill on-ramp a few minutes later, 3rd gear as well as some 4th, nothing but a few 0.35 KR counts.

Notice that downhill my WGDC went up to amost 100 to hold 20psi up top. Is that in part because of the low timing values? I would think if anything that would build more boost...

[Easter Bunny]

You have something mechanically wrong fucking your couch.

[JgamB]

I'm not familiar with Surefire remanufactured motors. (Google suggests sourced via Autozone?) Was the BNR installed along with the new motor, or had it already been running strong with a K04? I'd like to see how it behaves with stock timing and 0 WGDC since you've adjusted the WGA preload.

In other words roll it back to a base map.

And contrary to popular belief, we're usually here to help. It's not like you're asking about oil or front lips.

[qkrthnu2]

Yeah AutoZone, there are only a few major sources for remanufactured engines. I installed the BNR on the original motor after the K04 was smoking for a while. The original engine (135k) let go while I was still running spring pressure on the BNR.

I can certainly load a stage zero OTS map. What are you expecting to see?

[ms6mil]

Just to go along with the PM I sent and what J is sayin, I too recommend starting with a fresh OTS map. As far as what to expect.... It's just to eliminate any possible factors that are and most likely going on with whatever hardware issues you may have.

Your WG, boost tables need a lot of work. You can see the behavior of your WG here...


Go back to a OTS map (with the obvious sensor edits) and zero out the WGDC, the ramp limiter (High) and the under side of the BEC table. Leave everything else OTS. Take some logs then post em.

[qkrthnu2]

Ok I can do that. Just to be clear, stage zero OTS (load based) or a stage 1 (boost based)?

[ms6mil]

1,2 or 3 doesn't matter as you will be neutering the WG/comp tables. As long as you have the supporting mods, ie hpfp and IC.

Focus on one thing at a time. Start with the OTS, boost based, zeroed out map. confirm proper functionality of spring pressure. Post logs. Then we'll go from there.

[JgamB]

Originally Posted by qkrthnu2 Yeah AutoZone, there are only a few major sources for remanufactured engines. I installed the BNR on the original motor after the K04 was smoking for a while. The original engine (135k) let go while I was still running spring pressure on the BNR. I can certainly load a stage zero OTS map. What are you expecting to see?

I want to see if the timing on your reman is off and what kind of spring pressure boost your WGA preload adjustment created, and it should give some indication of whether or not the motor is healthy. Minimal boost + mild spark advance shouldn't yield any knock.

[qkrthnu2]

Ask and ye shall receive, fresh map and logs attached.

I Started with COBB Stage1+SF+DP 93 v234, zero'd out all of the boost target, comp and WGDC tables. Added in the 3 Bar MAP settings and my MAF cals.
The two logs attached were taken on the same stretch of road as the previous two runs I posted. First log is the 3rd gear uphill run, second is slight downhill 3rd and 4th.
Fuel is Costo (Top-Tier) 93 octane E10. Mods in signature are accurate.