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  • #91
    Originally posted by Def View Post
    You can probably reduce drag slightly with some little fences in front of the front tires. They are sticking way out there, so any bit you can do to shield them will likely help, especially now that your fenders aren't vented (can you put some small cut-out vents in the panel you made?).

    Also, any reason why you're going up in brakes so much up front? Or are you going to a Z33 track rotor or something?

    Any thoughts to engine mods?

    Definite yes on the front fences/canards or the equivalent. A splitter/front end treatment is on the short list before the next race at Calabogie in Canada (8/3-5). I also need to seal off the cowl area on the new hood as I think that was contributing to higher than normal engine temps (220F range). We ran out of time to get that done.

    As for adding ventilation on the panels I made, yea it's a good idea. I just need to find the right vents for my eye that will actually work. I was thinking about making a punch/die and doing something myself at my work also.

    As for the brakes, I'm experimenting more than anything else. Having the same compound front and rear with my rear kit and your fronts (12.2" OD front) was a hair too much rear bias. It's very close, but I'm erring on the side of caution for the endurance racing aspect. The 11 and 97 compounds aren't too far off in CoF though. The bigger front rotor does move bias to the front barely 1% so it was more for a "feel" change than anything else. I also picked up a 15/16" BMC based on my very long conversation with an engineer at PFC, so there were many changes (pads, BMC, rotor size, slotted rotors) which makes things more difficult to pinpoint.

    Balance was better for my application for sure. Pedal travel was definitely longer, but we weren't necessarily fond of it and the feel. Pad wear seems to be very good also and the pad/rotor combo is way quieter (I'm sticking with these PFC compounds for awhile I think). But, the caveat is, we lost some fluid and I think I see leakage at the BMC to booster interface for whatever reason. Brand new BMC also (Centric). I think I'm going to try a 17/16" BMC next. OR, I'm going to fab up a dual BMC setup that I have brewing in my brain.
    Core4 Motorsports
    CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
    S14 VQ AER Endurance Racing Team


    • #92
      Oh and as far as engine mods, this is something I struggle with because I do want them very badly, but doing so will put us in the next fastest class (the fastest) for sure, but still won't be quite enough power to compete for the overall win if there's no attrition. The last race we were in class 4 and we very happy to be so because we're at the pointy end (still need to share result from last race) there.

      If I do anything, I think it'll be either an UpRev tuner cable/software or a Link G4+ standalone so I can possibly make a "fuel efficiency" map and/or squeeze a few more HP out. We can squeeze out ~1hr25min from a full tank on track with no yellows with the current setup. That leaves us basically no strategy in regards to pit stops in a 9 hour race which requires 5 mandatory pit stops. More power will require fuel cell modifications and I don't want to deal (pay) with that change at this moment in time. Plus, the S14 tank is in such a great spot within the chassis and gets no starvation until the very end.

      When we're ready, we're all thinking a VQ37VHR and possibly give that "400bhp" Z1 motorsports package a shot. Even if it's only 375bhp, in the S14 at 2500-2600lbs, it'll move quite nicely.
      Last edited by gills; 06-07-2018, 08:02 PM.
      Core4 Motorsports
      CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
      S14 VQ AER Endurance Racing Team


      • #93
        On the brakes - I'd definitely go 17/16" MC. The pressure required for lockup still didn't seem very high on track with the pads up to temp IMO. Have you thought of shimming the MC prop valve and putting a proportioniing valve from Wilwood inline? I did it, and it wasn't hard. Very easy to tweak bias as you need. Then if it rains you can push bias back some to account for less weight transfer.

        On the power thing, is it peak power that you're rated on, or average power? Maybe you could up the VE a little bit, then flatten the peak to make your peak HP over a wider window?
        '18 Chevrolet Volt - Electric fun hatch for DD duty!

        DefSport Koni Sleeve and Spring Perch Buy!!!


        • #94
          Good to hear. Last time I had a 17/16 MC was on my S13 with full Z32 setup and an automatic S14 booster I believe. Touchiest damn brakes I ever used. But, that was definitely attributed to the booster as going to the B13 sentra one made a huge difference for modulation.

          I did have the MC prop valve shimmed, but I've also removed all shimming for the time being. Thinking of this, wouldn't it be best to just remove the internal prop valve completely to run an inline prop valve?

          We are classed based on lap times between the drivers on the team during qualifying. Then throughout the race, lap times are monitored closely to watch for sand bagging.
          Core4 Motorsports
          CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
          S14 VQ AER Endurance Racing Team


          • #95
            OK, long overdue update. I've had PRD (post race depression) and have been very busy at work since the last race, which was a rough one between the weather, bad luck, and poor decision making.

            Before getting into the results of the NJMP race, a bit of pre-race prep:

            At Watkins Glen while following a very well driven and setup E36 M3 (while I set my fastest lap time), I noted that he would lightly tap the brake pedal a couple of times on every straight away prior to a heavy braking. A lot of guys do this as an "inspection" so they know they'll have (or won't have) brakes prior to the braking zone.

            Many drivers do it to return the brake pads as close to the rotor as possible because of flexing in the wheel hub/bearing. The system under racing loads causes the rotor to push the caliper pistons back into the caliper a bit. This is called "pad knockback" as I'm sure most of you know. A few companies sell knockback springs to install inside the caliper to combat this. It is something that I experienced very much in my old 2004 STi that had the older 5x100 wheel hub and bearing assemblies.

            I never thought I'd need to do it on the S14 because it is fairly light car and things seem to be robust. But, I figured I'd test it out while following this guy as he was giving me a constant reminder. Much to my surprise, the pedal travel reduced notably vs when I didn't do it. The hubs/bearings on the car have been on it since the beginning so I figured it was probably best to the change them anyway and inspect them. So I procured new OEM hub/bearing assemblies all around, new ARP extended wheel studs (M12x1.25 all around ....more on this later), and new Muteki SR48 lug nuts, just to cover all bases.

            And to top it off, I purchased some of that fancy NEO Synthetic wheel bearing grease that I'm sure most of you read about in the ubiquitous MotoIQ article. Since I'm endurance racing, I figured that this is probably can't hurt.

            The process that the MotoIQ article goes through is pretty accurate, although he doesn't make mention of the outer seal on the inboard side that needs to be removed in order to pull the balls out. It's not difficult, but you need to take care with a small flathead screw driver slowly working your way around to pry it up and out. Only then, can you remove the inboard balls. This is probably the "hardest" part.

            Anyway, here's a brand new OEM bearing. Same yellowish, waxy grease is still used. You can see the seal that needs to be removed that I referred to:

            Practice run on spare hubs I had on the shelf:

            And here's a hub/bearing that was on the car since I've had it:

            I still have yet to pop the balls out of those bearings, but at the very least the inner races and the balls look fine. I have yet to fully inspect the outer races. I was also expecting to see the OEM grease not be yellow, but rather cooked, greyed, and darkened. As you can see, that certainly isn't the case. There's significant racing and track time hours on those bearings. To top it off, I don't run any brake ducting either so these aren't getting cooled off much at all.

            And if you're wondering about re-greasing the rear bearings, I didn't, but the process will be nearly identical. I just ran out of time.

            Ready to go. Now I have full spares for hubs/bearings, wheels studs, and lug nuts:

            About those ARP extended studs. Apparently you used to not be able to get ARP M12x1.25 studs all around for S-chassis, only M12x1.5. If you want M12x1.25 all around, for S14 you get Subaru WRX ARP kit 100-7716 for the front, and for the rear you get these from ConceptZ, which they had ARP custom make a few years back: click here (use these all around for S13).

            I really wanted to go with ARP vs. the other random brands you can get off of ebay.

            Other big-ish changes were with the brakes. After a conversation with a PFC engineer, we went with 11 compound front, 97 compound rear and as per his suggestion, we tried a 15/16" BMC (from a 1"). Also moved to slotted rotors all around, and bumped up the rotor diameter in the front to 12.72" (from 12.2); the max diameter available with a 8 x 7" rotor bolt circle from Wilwood. The slots can potentially help combat squeal/noisy brakes.

            Rocking Defsport:

            Threw some temperature indicating paint all over stuff also. Was curious if things were reaching dangerous temperatures:

            My teammate was determined to get rid of the hot-air intake we had. Definitely cost some power in the middle of a hot 9 hour race. Used some HDPE sheet we had sitting in the garage forever to construct an airbox of sorts, and some G35/Z33 tubing/adapters from Z1performance to extend the intake. Considering the time crunch, he did an awesome job. Although not measured, it must be an improvement for IAT.

            "CAD template" (if you haven't yet, go watch the "Project Binky" video series. If you appreciate fabrication and car stuff, you will most likely love this: Bad Obsession Motorsports:

            Lastly, had another oil analysis done after Watkins Glen to see if things were healthy and if the oil could go another weekend. After 27 hours of racing, going to give this batch another go:

            Also trying a different tire out. Went with a set of the Hankook RS4 as this race's fresh tire. Still have Falken RT615K's as backup.

            Race update coming next....

            Last edited by gills; 07-24-2018, 12:45 PM.
            Core4 Motorsports
            CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
            S14 VQ AER Endurance Racing Team


            • #96
              Any idea how much that 12.72" assembly with Defsport hardware weighs??


              • #97
                New Jersey Motorsports Park, 5/2018

                Saturday's 9 Hour Race

                "Please don't rain, mommy"

                The one picture that basically describes this entire day:

                We qualified 17th overall with a 1:59.8xx which was FINALLY good for class 4 (Reminder, we don't want to be in class 5, which is the fastest class and what we always end up in). All it took was a sh!t ton of rain! That lap time is basically 30 seconds slower than a proper dry lap in our car.

                So all this time we've been gambling on the weather and just hoping that it would never rain on us. Well, the hope finally wore off. With no 'real' rain setup, our car was a handful in the wet stuff. And by handful, I mean scary AF. By the time we realized we'd be screwed with rain, it was too late to make any significant setup changes (softer springs, small tire, better tire, etc..). Combine that with human foot ABS and traction control (unlike some of the fancy teams that are gracing AER with their presence) and it's a recipe of butt puckering. The only thing we did was add lighting to make sure people would see us.

                I took out front camber (down to -2.5), removed gas pressure from the shock reservoirs, and went to almost max soft on compression and rebound damping. It was also somewhat cool out so I took out some tire pressure in an effort to get the tire to squirm some more heat into the carcass. To top it off, RS4's are not good in cool, wet conditions, which we can definitely confirm! The track was insanely slick on the dry line, to the point where it literally felt like driving on ice when crossing over it then finally getting grip in the rain line.

                Heading out for the parade laps through monster puddles:

                In hindsight, not so sure that was the best idea (low tire pressure) in the type of rain on this day. It was a lot, and hence there was a bunch of standing water. Higher tire pressures are better for hydroplaning resistance, which became the more important factor in many parts of the track.

                Green Flag! Hey look, at least the lights are working well...


                So the goal of this day was not to crash and not get crashed into, and we were successful. 2 drivers had significant off road excursions and luckily were able to come back on track. We were also almost successful scoring a 3rd place podium finish as well. But, the Race Gods just weren't having it. Using a window squeegee to defog the windshield while going 100mph down the straight just wasn't enough for the Race Gods.

                (some video from the live stream to give you a moving pictures idea of the poor visibility)

                About 30 minutes out from the finish, in 3rd place with no more stops to go, I got a flat tire. Looks like a rivet from a piece of body work that was ripped off from the deep puddles did us in:


                Would've been an amazing ending to a terrifyingly fun day.

                Not surprisingly, a turbocharged FWD car (Chevy Cobalt) won class 4 for the day.


                Team fastest lap: 2:03.2
                Overall fastest lap: 1:53.7 (IMSA driver Al Carter in a worked E46 M3)

                (Some good "racing in the rain" reading material from Grassroots Motorsports Magazine:

                Core4 Motorsports
                CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
                S14 VQ AER Endurance Racing Team


                • #98
                  Sunday's 9 Hour Race

                  In the back of our minds we were all thinking about Sunday as the radar and forecasts were showing a drier and warmer, more humid day. I set the car back up with dry front camber settings, rechecked toe and reverted back to typical dry tire pressures and damping settings Saturday night. We obviously also had to switch back to our set of Falken RT615K tires due to the RS4 flat. We know them well...

                  Beginning of the day, the track started off wet from the previous day's rain. Took about an hour to get within 4-5 seconds of the car's/track's typical dry pace. The car may be terrible in the rain, but it can certainly haul ass in the dry.

                  Green Flag (need to build out some fences/fenders for the front tires, eh?):


                  Midway through the day it was apparent that we were a favorite to win class 4. We focused on being strategic with pitstops, i.e.-pitting during full course yellows/safety car laps. So much so, that we gambled on bringing in our 3rd driver about 15 minutes earlier than normal to take advantage of a fairly lengthy full course yellow. Based on what we knew of fuel consumption of the car at the time, it seemed like a winning decision. That certainly came to bite us in the ass later....

                  Dry weather, WOOHOO!:

                  BUT, not without something else coming to bite us in the ass first. During the 3rd pitstop, my brother (who was getting in the car to drive) forgot to lower his visor once over the pit wall. All visors must be down and no work can be done on the car during fueling. The stewards saw the violation and handed us a drive through penalty. Even with that drive through penalty, we were still 1st in class.

                  We thought that perhaps the organizers had something against us since we were handing many BMW's their asses. Then we checked the vid.....caught red handed:

                  So as much as that sucked, one really cool thing about AER is that they send out team specific and mass text messages throughout the weekend giving you information about violations, pit stop times, number of pit stops, the current driver in the car, general race updates, other teams needing parts, etc. Information about the race is shared instantly in real time and direct. It's very efficient. They are definitely ahead of the game in this regard.

                  Fast forward to my stint, which started at 2:54pm. Race was ending at 6pm with one required pit stop remaining to do in that time span. With the knowledge that we can squeeze out 1.5 hours per tank, it was cutting it close on paper. I usually do a double stint to finish the day, although it typically ends up being more like ~1.75 stints most races. But, we were being more aggressive with the earlier pit stops this time around.

                  We obviously wanted to max out my first stint, so fast forward about 1:10 and I'm communicating with pit about when to come in. One curveball that we weren't ready for was that I was starting to get heat exhaustion in the car. I regrettably didn't drink as much water/liquid as I usually do before getting in the car this time around in an effort to not have to piss like a race horse during my stint like I always do. Probably wasn't a good decision. I was also having an issue accessing the camelback during my stint so I also didn't drink enough in the car also.

                  (Video of me struggling to find camelback)

                  We've survived all this time without a rain setup and we've also survived without a Coolsuit setup. But, this time, there was no way I was going to be able to do a double stint without one. There wasn't a single yellow flag during my stint and I was in it to win it almost the whole time. Hot and humid southern Jersey that started getting to me this day. I let the team know that someone else needs to get suited up to go in for me.

                  (I managed not to put 4-off on the previous day's ice rink of a track. But, the heat got to me, and of course, it was while getting pointed by a team that we are very friendly with:
                  Heat Exhaustion 4-off video clip)

                  The Volvo team that we always pit next to at New Jersey and who pointed me by in the video:

                  Inevitably it turned into a scramble in the pits. The driver I wanted to go in wasn't suited up yet as we all thought I had another 15 minutes of fuel in the car and I was ok with going that much more time. As I was insisting on them to all be ready ASAP because I was overheating, I got fuel cut a little before pit in. I immediately made the decision to pit so I didn't run out of fuel on track, which happened to me on Friday practice very shortly after hitting fuel cut. I informed the pit. They were barely ready. I was out on track for a total of 1:24. Not a single full course yellow contributed to this shortened stint. We were in 3rd overall, 1st in class at this point by a comfortable margin.

                  During the scramble, the driver going in wasn't able to get his ear buds for communications in on time. He informed me of the situation and we were relegated to using pit boards to communicate with him. He went out and we still had 1st in class, dropped down to 4th overall. We had about just under a lap lead over P2 still after this. Because of my surprise early pit stop, it meant we had to bring the last driver in for an extra pit stop for a splash of fuel. He went out at 4:22, which left 1:38 left on a tank of fuel...not going to happen.

                  What took place from that moment on was riddled with indecision. We had the win in the bag, but it was our race to lose. It should've been simple, but only in hindsight is it ever. The second place car behind us was a 'detuned' E36 S54 swap (#955 Just For Fun Racing) with basically no aero like our car. These guys have been a juggernaut with winning Class 4 for consecutive races. Where we screwed up was not letting our driver know to push as hard as he can to build a larger gap. He was in a more conservative mode to try and stretch the fuel out. That's all he wanted to know when he was out there, whether to push or conserve. We failed at parlaying that information to him.

                  The next failure was when we pulled him in for the "splash" of fuel. We ended up putting in about 1.5 jugs of fuel where we could've easily have gotten away with 1 jug. Filling that extra 1/2 of jug of fuel eats up about a good 15-20 seconds. Far too long in the instance we were in. While he was going down to pit exit, #955 passed us. We were released back on track about 16 seconds adrift at 5:27.

                  At that point it was no holds barred. Our driver managed to cut the gap to 7 seconds. He was steadily gaining on #955 and would've passed them...until the unthinkable with about 15 minutes left in the race....RAIN. The heavens opened up with a sporadic downpour that basically vaporized our chance of winning. #955 was already setup with softer springs and smaller tire for the rain from Saturday. There was no chance in catching them at that point. Unfortunately I have no good pictures of that moment when it started down pouring.

                  #955 took P1.

                  Core4 Motorsports took P2:

                  Team Fastest Lap: 1:32.8
                  Overall Race Fastest Lap: 1:28.7 (Nelson Canache, Mustang BOSS 302R)

                  Core4 Motorsports
                  CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
                  S14 VQ AER Endurance Racing Team


                  • #99
                    Originally posted by RalliartRsX View Post
                    Any idea how much that 12.72" assembly with Defsport hardware weighs??

                    I'm usually a stickler with that type of stuff, but I didn't get around to weighing it before and after. I will weigh it when I have it off the car again.
                    Core4 Motorsports
                    CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
                    S14 VQ AER Endurance Racing Team


                    • When you say fuel cut, your engine as starving for fuel? Or you have some kind of setting with your ecu?


                      • Originally posted by clotuning View Post
                        When you say fuel cut, your engine as starving for fuel? Or you have some kind of setting with your ecu?

                        Yea, that's a good point. Fuel cut due to fuel starvation. The S14 tank and pickup does an admirable job for an OEM setup. We can take it pretty low.

                        OH, and I forgot to give you a shout out for coming on down on practice day that weekend and trying to help me out with the PodiumConnect. Much appreciated!
                        Core4 Motorsports
                        CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
                        S14 VQ AER Endurance Racing Team


                        • So, about them brakes....

                          We've gone through a few combinations of calipers, pad compounds, and rotors. But, the one thing that has remained constant is the brake master cylinder size. For the Waktins race this year (and all prior races) we were on a 1" BMC (shimmed, not shimmed, and kinda shimmed...). Even with the caliper upgrades, rotor sizes increasing, etc, the biggest complaint (if we are to split hairs) has been about feel and modulation.

                          So, we decided to [subjectively] test the old argument of whether a larger or smaller BMC will aid with feel and modulation. The general consensus is that usually a smaller BMC aids in modulation because it makes for longer pedal travel with a smaller amount of pedal force for a given system pressure. That longer pedal travel gives you more 'resolution' of sorts through the pedal stroke. Vice versa for a larger BMC.

                          I've always been in the "you don't modulate your brakes based on pedal travel" camp so I've been skeptical of going smaller. But, after conversations with PFC and a few others, I decided to try the 15/16" BMC for the NJMP race.

                          The result was just 'meh.' I could definitely feel the longer pedal travel when compared to the 1" BMC, but the modulation and feel was similar to the 1" BMC to me. My co-driver thought it was worse.

                          Next up was the 17/16" BMC that we just ran at an open test day last Friday. No other changes on the car except for that. It was a unanimous decision; we have a winner! Everything about the change was positive. Higher pedal force threshold to lock up the brakes, shorter travel, easier to modulate. It really addressed most of our complaints (until we get bored and try to find more) about our Frankenstein braking system.

                          Not only that, it also confirmed my suspicion about the smaller BMC provides more feel/modulation mantra. At least in my case.

                          My current setup which is the best the brakes have felt yet all around. And to top it off, they don't squeal. Huge fan of the PFC compounds so far:
                          • B13 Sentra non-abs booster (this is important)
                          • 17/16" brake master cyclinder (not shimmed)
                          • Stainless steel brake lines
                          • Front (Defsport hats w/ Core4 radial bracket)
                            • Wilwood FSL6R Calipers (4.04 in^2 piston area)
                            • 12.72" x 1.25" Wilwood Spec37 HD slotted rotor rings
                            • PFC 11 Compound
                          • Rear (Core4 rear BBK)
                            • Wilwood Forged Narrow Dynalite Calipers (1.98 in^2 piston area)
                            • 12.2" x 0.81" Wilwood Spec37 HD slotted rotor rings
                            • PFC 97 Compound

                          If this was a track day only/TT type car running R-compounds or slicks, I'd get more aggressive PFC compounds.
                          Core4 Motorsports
                          CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
                          S14 VQ AER Endurance Racing Team


                          • Did you ever get a chance to weigh the front 12.72" floating setup (atleast the rotor)?? Curious to see how much the rotor setup weighs.


                            • Originally posted by RalliartRsX View Post
                              Did you ever get a chance to weigh the front 12.72" floating setup (atleast the rotor)?? Curious to see how much the rotor setup weighs.

                              I didn't yet. I will be sure to do that. I haven't had the need to pull anything off yet, but will soon.

                              You test out your brakes yet??
                              Core4 Motorsports
                              CLICK HERE for Wilwood FSL6R Radial Bracket & Rear Wilwood BBK GROUP BUY
                              S14 VQ AER Endurance Racing Team


                              • Oh. No need to hurry or pull them. Thought you had them off and measured.

                                Wont be testing my brakes until (fingers crossed) late September. I am moving on to the last big project (wiring) then waiting on one last part (which is making me impatient as its been almost 2 months to get the custom oil pan baffles made.....grrrr). Will report back once complete. Still need a set of track wheels and Konis prior to lowering it on all fours.