John's BNR S3 daily driver performance build

I would check the two rear lower control arm bushings (inner and outer), and any other bushings you may have loosened. I had camber arms installed and a front control arm brace so I had a few more to check.

The bounce was also alleviated by dialing in camber properly. I went from -2.3* to -1.8* in the back and had less bounce with more grip once it was all set. Again it's just a thought, something to check if need be.
 
Torque your suspension bushings while loaded...that's an interesting one. I'm having trouble figuring out how any of your suspension bushings got loosened in the first place just to install a set of coilovers, other than the one that's in the lower control arm in the rear that you take off to put the springs in, and I doubt that would have any meaningful impact on the ride. My bushings are all in fine shape as far as I can tell. The front control arms spring back the way they're supposed to and behave the same on both sides. I have thought about upgrading the bushings, but a couple local autocrossers have had longevity issues with one of our only real viable options (Whiteline).

I haven't checked tire temps yet because I have yet to run more than factory camber. Even when I had the GC camber plates on, they were set at the factory position. I know my car will need more camber and will cross that bridge when I come to it.

I'm not surprised the KW's feel bouncy honestly considering the spring rates aren't set up to achieve flat ride.

@Redline I don't mind talking about your setup, but would prefer to talk about it in your thread to keep things organized.
For sure, man. My apologies. I responded late after a long day (wife had surgery) and didn't realize we were in your thread. I'll be more careful :)
 
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My factory camber in the rear has been at -2.5° on the driver's side and -2.2° on the passenger side since day one. Something I plan to correct in the future using my SPC camber arms, which are currently at the factory length. I suspect the camber is excessive since with my RS3's, I have to air down my rear tires to about 30 psi, otherwise the outer edges will not wear. Meanwhile on the front, the outer edges are getting wrecked, so for sure I need more up there.

I didn't loosen any bushings in the suspension other than the outer rear LCA ones, so that I could install the rear springs. I don't understand which other bushings you could have possibly loosened, as nothing else is necessary to perform a coilover swap.
 
Uninstallations.jpg


My car seems to be undergoing a full devolution this season. I have been working on the car, I pulled the turbo and sent it to Bryan for repair. USPS has apparently lost the turbo.

USPS_Lost_turbo.png

RIP_BNR.jpg


A local is bringing me a spare K04 tonight, which I'll install temporarily until I can get the insurance money from USPS to get another used BNR S3. A real shame, as my BNR at 35k catless miles had literally no detectable shaft play and still looked brand new.

After breaking my VTCS actuator, a nator was kind enough to send me a new one. I found out the Gen1 and Gen2 actuators are different. Now I'll need to pick up another one. (Gen2 on left)

VTCS_actuators.jpg


...and my Corksport bypass valve spring failed in two places. CS is sending a replacement that is stronger.

BPV_spring_failure.jpg


Only other thing of note in this update is that installing this methanol injection kit has been, by far, the worst car installation experience of my life, and I will no longer recommend methanol injection kits to anyone. I already spent an equal or greater time just putting the HTP methanol tank in as actually pulling the turbo and IM/fuel rail off (a lazy beer-drinking 6 hours or so), and haven't even remotely started figuring out how I'll run the AEM wiring through the firewall and to the defrost vent. Part of the problem is that there is nobody within 100 miles of me that has done these things before... Part of the problem is that Mazda designed the interior and exterior of these cars to be impossible to service...and then the main problem is that the FSM is useless...it took me two hours to get the front bumper cover off, and that's while damaging it in multiple places. The FSM shows about 1/2 of the actual connections of it to the body, and there is a wiring harness clusterfuck you will need to disconnect from the body in like 4 places.

edit: One cool thing I forgot to mention - 109k miles on the odometer. Zero injector seal failures. Putting new CS ones in.
 
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Uninstallations.jpg


My car seems to be undergoing a full devolution this season. I have been working on the car, I pulled the turbo and sent it to Bryan for repair. USPS has apparently lost the turbo.

USPS_Lost_turbo.png

RIP_BNR.jpg


A local is bringing me a spare K04 tonight, which I'll install temporarily until I can get the insurance money from USPS to get another used BNR S3. A real shame, as my BNR at 35k catless miles had literally no detectable shaft play and still looked brand new.

After breaking my VTCS actuator, a nator was kind enough to send me a new one. I found out the Gen1 and Gen2 actuators are different. Now I'll need to pick up another one. (Gen2 on left)

VTCS_actuators.jpg


...and my Corksport bypass valve spring failed in two places.

BPV_spring_failure.jpg


Only other thing of note in this update is that installing this methanol injection kit has been, by far, the worst car installation experience of my life, and I will no longer recommend methanol injection kits to anyone. I already spent an equal or greater time just putting the HTP methanol tank in as actually pulling the turbo and IM/fuel rail off (a lazy beer-drinking 6 hours or so), and haven't even remotely started figuring out how I'll run the AEM wiring through the firewall and to the defrost vent. Part of the problem is that there is nobody within 100 miles of me that has done these things before... Part of the problem is that Mazda designed the interior and exterior of these cars to be impossible to service...and then the main problem is that the FSM is useless...it took me two hours to get the front bumper cover off, and that's while damaging it in multiple places. The FSM shows about 1/2 of the actual connections of it to the body, and there is a wiring harness clusterfuck you will need to disconnect from the body in like 4 places.

Way to go @CorkSport - Derrick ;)

Also nice Stingray over there John. I might know a guy that works on those....too much fun for the money.
 
CS is taking care of the situation with the spring...no worries.

That is actually a grand sport. It is my roommate's. It is a truly badass vehicle for the money. I think an S3 might be able to give it a run for its money...IF I HAD ONE
 
CS is taking care of the situation with the spring...no worries.

That is actually a grand sport. It is my roommate's. It is a truly badass vehicle for the money. I think an S3 might be able to give it a run for its money...IF I HAD ONE
Around the track.... not likely unfortunately. But in a straight line from a roll...yeah probably :)
 
He got the super sports with his... I told him he should have gotten the sport cups. Oh well.
 
Uninstallations.jpg


My car seems to be undergoing a full devolution this season. I have been working on the car, I pulled the turbo and sent it to Bryan for repair. USPS has apparently lost the turbo.

USPS_Lost_turbo.png

RIP_BNR.jpg


A local is bringing me a spare K04 tonight, which I'll install temporarily until I can get the insurance money from USPS to get another used BNR S3. A real shame, as my BNR at 35k catless miles had literally no detectable shaft play and still looked brand new.

After breaking my VTCS actuator, a nator was kind enough to send me a new one. I found out the Gen1 and Gen2 actuators are different. Now I'll need to pick up another one. (Gen2 on left)

VTCS_actuators.jpg


...and my Corksport bypass valve spring failed in two places. CS is sending a replacement that is stronger.

BPV_spring_failure.jpg


Only other thing of note in this update is that installing this methanol injection kit has been, by far, the worst car installation experience of my life, and I will no longer recommend methanol injection kits to anyone. I already spent an equal or greater time just putting the HTP methanol tank in as actually pulling the turbo and IM/fuel rail off (a lazy beer-drinking 6 hours or so), and haven't even remotely started figuring out how I'll run the AEM wiring through the firewall and to the defrost vent. Part of the problem is that there is nobody within 100 miles of me that has done these things before... Part of the problem is that Mazda designed the interior and exterior of these cars to be impossible to service...and then the main problem is that the FSM is useless...it took me two hours to get the front bumper cover off, and that's while damaging it in multiple places. The FSM shows about 1/2 of the actual connections of it to the body, and there is a wiring harness clusterfuck you will need to disconnect from the body in like 4 places.

edit: One cool thing I forgot to mention - 109k miles on the odometer. Zero injector seal failures. Putting new CS ones in.
Dang, man. Sorry about the run of bad luck. Installing methanol definitely can take some time, especially if you're adding extra components, like various illuminated switches. I've found that the firewall access behind the glove box is by far the best place to pass wires from cabin to underhood. Not sure if it'll help, but:
http://mazdaspeeds.org/index.php?threads/bnr-s3-methanol-awesomeness-i-hope.931/
 
Dang, man. Sorry about the run of bad luck. Installing methanol definitely can take some time, especially if you're adding extra components, like various illuminated switches. I've found that the firewall access behind the glove box is by far the best place to pass wires from cabin to underhood. Not sure if it'll help, but:
http://mazdaspeeds.org/index.php?threads/bnr-s3-methanol-awesomeness-i-hope.931/

Yup, I'm aware, but my AEM wiring is so short, I'd have to extend literally everything to get it to the passenger side. Of course, it's looking likely that I'd have to extend a bunch anyway because all of the wires are too short.

How did you gain access to that plug on the passenger side, and how did you get the wires over there from the driver's side? I can't get the inner glove box out, it seems really stuck in there and there are what appear to be three clips on the bottom I can't get to disengage.

How did you remove the kick panel on the driver's side with the fuse box and everything? I also cannot figure this out. It looks like the trunk release is somehow connected to this section.

Fuck Mazda interiors.
 
Yup, I'm aware, but my AEM wiring is so short, I'd have to extend literally everything to get it to the passenger side. Of course, it's looking likely that I'd have to extend a bunch anyway because all of the wires are too short.

How did you gain access to that plug on the passenger side, and how did you get the wires over there from the driver's side? I can't get the inner glove box out, it seems really stuck in there and there are what appear to be three clips on the bottom I can't get to disengage.

How did you remove the kick panel on the driver's side with the fuse box and everything? I also cannot figure this out. It looks like the trunk release is somehow connected to this section.

Fuck Mazda interiors.
Basically, you have to remove and slide back the whole center console. That's necessary to remove the lower dash on the driver's side. You have to remove the Mazdaspeed plate in front of your seat (which you step over during ingress), then pull back the interior rubber liner that goes all around the door entry, particularly in front of the section by/above/below where the fuse box is to get that panel out. For the hood release latch, pulling/holding it open all the way then sliding a trim removal tool between the top of the latch and the panel will release the clip that keeps it in place. Then, you'll have access to the screw behind it. The lower dash on the passenger's side is a lot easier. But the whole process is like 9-steps for the driver's side. I've gotten quite adept at it, LOL. Here's the page in the service manual that shows the steps and section references (I'm sure you have the manual, right?):
attachment.php

I got the wires to pass through from driver's to passenger's side through a slot that you can see when you unbolt/slide back the center console. It's basically in a spot that's below and behind where the cigarette lighter and cubby rest. Once you pull off the center console kick panels on either side at the front of it, you remove the shift knob, e-brake cover, shifter boot panel, and cubby/cigarette lighter panel (which has two plugs to disconnect). Then, unbolt and slide back the center console (which kind of requires a karate-chop/instantaneous popping it back if it's never been done the first time - I found it useful to sit in the back seat right behind it, grab it from both sides and quickly pull/pop it backwards). Don't forget the bolts underneath the felt in the storage area at the back of your center console! There are various bolts in all sorts of places you may not know about, so refer to the sections above. When you've slid the center console back, you'll be able to see the pass-through I used.

Lemme know if this makes sense. I may be able to easily snap a few pics.
 
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Overlay I put together today after tuning the K04. 2:10 methanol:gas BNR S3 (blue), E33 K04 (red). K04 tune is about as maxed as it gets. BNR tune is semi-conservative. BNR spools later and makes peak power later. Nice to be able to quantify the difference between the two. You can see why the K04 is preferred for autocross, makes a lot more power below 3000 RPM's and also has amazing response down there. You can also see it has miserable torque output after 4500 RPM's.

Identical bolt-on's, logs taken less than 3 months apart.

 
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Overlay I put together today after tuning the K04. 2:10 methanol:gas BNR S3 (blue), E33 K04 (red). K04 tune is about as maxed as it gets. BNR tune is semi-conservative. BNR spools later and makes peak power later. Nice to be able to quantify the difference between the two. You can see why the K04 is preferred for autocross, makes a lot more power below 3000 RPM's and also has amazing response down there. You can also see it has miserable torque output after 4500 RPM's.

Identical bolt-on's, logs taken less than 3 months apart.

Good info, though it looks like you WOT'd several hundred rpms later on the BNR? That'll definitely affect wtq down low. It's clear to see how steep the K04 spool is - very quick. The BNR is just a little less so, angle-wise. Here was my comparison between K04 and BNR S3. It does appear the K04 is more efficient down low as I WOT'd at virtually the identical rpms. From 4,500 on, though, the BNR spanks the K04 very hard:
upload_2016-12-4_22-25-6.png
 

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Good info, though it looks like you WOT'd several hundred rpms later on the BNR? That'll definitely affect wtq down low.View attachment 4587

The RPM I went WOT at with the BNR log is low enough that it spools about as early as it can possibly spool. You can tell by how low the angle is of boost coming on like you pointed out. Bottom line the BNR is going to give you slightly worse times in tight autocross courses. Of course, it also won't throw a rod through your block either.

edit: UPDATE:



This car met its untimely demise when I switched to my RS3's one evening and then decided to take a turn way too fast at 45°F in the middle of the night, and turned in too fast on top of that. Rear end snapped around, hit a guardrail. RIP. Geico paid me out and I bought a new car, which will have its own thread. Totally my fault. Wasn't driving the way I would normally drive and paid the price.
 
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