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Jdog's G37 RWD AT Sedan - Journey into the 12s (Nitrous Project)
Hello folks, this post is well overdue. I would like to thank the active members for their posts over the years. The information I have found here has been a tremendous help. I been modding my car for almost 4 years now. Done 90% of the work myself. Lots of trial and error, swapping intakes, exhaust, tuning, re-tuning and etc. My best quarter mile time at the Auto Club Speedway in Fontana, California was 13.224 @ 105.35 (DA 1906ft, .70+ slope, 60 foot is typically in 2.0X secs). Probably could hit 12s on a level track and good DA. My first time at the same track it was running 14.2s with SRIs and a tune... I cut a second off the 1/4 mile, but that's not enough... My goal has always been to get into the 12s and I have decide to go the Nitrous route . I am taking my car in next month to get it tuned with 70hp shot. Wish me luck!
Performance Mods:
- ECUTEK @ Tuned by Seb
- HKS 1 step colder plugs
- Z1 VQ37 Intake Plenum Power Mod
- Stillen Grounding Kit (removed, caused charging problems)
- Kinetix High Flow Cats
- Motordyne XYZ Exhaust Y-Pipe, Resonated (replaced Tanabe Y-Pipe)
- Tanabe Medalion Touring Exhaust
- Custom Mid Pipe with used Coupe Resonators 2.5" in 2.25" going out (no rasp/droning)
- Injen Long Tub Intakes (replaced SRIs)
- Ported/Polished OEM Throttle Bodies
- Ported Lower Intake
- GTR Injectors
- Specialtz - 370Z/G37 Flex Fuel Kit
- Deatschwerks DW300 Fuel Pump
- CJ Motorsports Bullet Fuel Pump Hat
Drag Racing:
- NST Pulleys / Gates Racing Belt
- VLSD 3.69 Diff swap (from 2013 G37s M/T Coupe)
- Nismo Diff Cover / WL Bushings
- Drilled & Slotted Rotors
- Custom Carbon Fiber Single Piece Drive Shaft
- Paddle Shifters
- Bell rear differential brace (removed, modded, reinstalled)
- Nitrous Outlet 370z kit
- Nitrous Outlet WiMax Controller
- Nitrous Outlet 10 Bottle with NHRA blowdown x 2
- Nitrous Outlet Purge
- Nitrous Outlet Bottle Heater
- Nitrous Oultet Bottle Pressure Sensor x 2
- Nitrous Outlet High Flow Filter
- NX Maximizer Ez Progressive Nitrous Controller
- Custom Nitrous Bottle Holder
- 4 x 17X8 KOSEI K5R (7 pounds lighter than stock)
- Nitto NT555R 245/45R-17 in the rear (replaced with M&H 275/45/17s)
- B&M Line Locks
- AAD W1 Catch Cans
- IPT Valve Body
- IPT Torque Converter
- Fast Intentions Flex Plate
- Z1 Urethane Motor and Transmission Mounts
- 2 x Jegs Exhaust Cutouts 2 3/8 in. OD
- Secret Sauce
Appearance:
- Tail as Turn LED Module
- Carbon Fiber Trunk Spoiler
- JDM Style Lip / Spoiler
- Fully Torqued Racing Aluminum Front Splitter Lip Support Rods
- TBW Aluminum Under Tray SILVER
- TBW Aluminum Diffuser SILVER
- Custom Engine Cover
- G35s Sport Rear Rims paired with Michelin SSs - 18 x 8.5 in the rear (match 18 x 7.5 premium G37 rims pattern in the front)
You are probably asking why there's no headers, test pipes, larger exhaust pipes, larger intakes, why is not lowered, on stock rims and etc on this list... I live in California and Smog, CARB, Roadside Inspection Programs are a PITA. This car will and has passed smog at STAR stations without removing anything. I always kept it looking and sounding like stock (sleeper) as much as possible to avoid any unwanted attention
Had to fix a small exhaust leak on a weld the other day. This was a great opportunity to take a few pics underneath of my custom exhaust. Heat wrap is there to protect carbon fiber driveshaft on both ends. Look closely enough and you can see the carbon fiber drive shaft. Reinstalled diff brace
Last edited by jdog78; 10-17-2019 at 08:52 AM.
Reason: Revised
I had to re-do the grounding in the engine bay and inside the car. Nitrous Outlet thinks the purge fried due to how I was grounding things. They replaced it free of charge! Make sure all your grounding wires are home runs, lesson learned, and the purge works great now. I also re-did some of the hose and wire management while I was at it. Now to the fun part, I finally got to do some Nitrous testing today! My tuner sent me over a map to try and I have been dying to test it. The goal this weekend was to see if things are firing off and if I had any leaks anywhere. Nitrous Outlet setup worked as expected. But there was a few issues. 1. My n2o map was causing injector duty to drop to 5/6% which caused it to lean out during shifts. 2. I wasn't getting enough fuel when n2o kicking in (leaning out a bit). Turns out part of the problem I was using the wrong size fuel jets (55 psi). My fuel pressure drops to around 36 psi WOT (idle at 58 psi). Figured it out with my gopro... Youtube video below and some pics. I'll be dropping in 45 psi fuel jets this weekend. Verified both problems by running/logging with/without spraying. I did my spraying from 5.8K / 5.9K while testing, checked for DTCs afterwards. So far so good. I’ll leave the tuning magic to Seb @ Specialtz. Hopefully I'll have better luck next weekend.
Thanks man! Will do, I ran into some fuel pump issues that has stalled things (literally). Turns out it's not supposed to drop pressure like that and it was causing my car to lean out when spraying... Spent the whole weekend troubleshooting it... I was able to get my N20 controller working though. I'll do a video on how I setup that up later.
Still working out the fuel pressure issues, here's the latest:
I have been doing some testing and I am getting closer to a solution. With the OEM pump / different assembly in there it was running leaner (13.0 AFR average from 4300 RPM on to 60 MPH), target is 12.38 at WOT. With the DW300 pump it was running 12.5 at WOT a month ago when I noticed it. But there was a small leak in the tank causing it to lose pressure when it was turned off. When I put in the OEM pump I discovered that it held pressure and that the leak was in the tank. Now that the DW300 pump is back in there with no leak (holding pressure when off) it's at 12.1 at WOT now (running rich). I am getting a new pressure gauge in a few days to test out. Even with 12.1 at WOT the needle is bouncing around going under 40 PSI (regardless of pump/assembly). It's going on the DYNO in the week for further tuning and I am hoping to get this all sorted out before then... Note I am not spraying during AFR examples above.
Notes on test runs: Fuel Tank of Gas New Battery (voltage runs about .2 higher when charged) Drilled 12 small holes at the bottom of the canister on the DW300 assembly
No leaks!
Well I think I can finally say I am ready for tuning this Wednesday The fuel pressure saga appears to be over. Thankfully I did get my AFR richer / more pressure by doing the following:
1. Replaced my cheap Walmart battery with a Bosch Platinum Series AGM Battery Group, Size 35
2. Removed the Stillen grounding kit from the car. Turns out it was preventing my alternator from charging at full capacity. With it on my car it would charge at 13.2 volts, with it off 14.4 volts... Probably is the reason I have had to replace my battery twice with it on... No joke.
3. Found that the Fuel Pressure Adapter Fitting that had my gauge and fuel pressure sensor were threaded into far going up into the fuel solenoid. Which was slightly narrowing the feed going up to the fuel solenoid and possible causing the fuel pressure reading to be off.
4. Replaced the fuel pressure gauge, readings are now at idle 56 PSI and drop to mid 40s PSI. The fuel pressure gauge is not going directly to the fuel injector rail, it's going up to the fuel solenoid. So the pressure readings are probably not 100% accurate to begin with. But better non the less.
5. Drilled 12 small holes at the bottom of the canister on the DW300 assembly. I am not sure if this helped or not. But since I have pulled the pump like a dozen times, it couldn't hurt.
6. Isolated / fixed the fuel pressure drop with the car turned off to the fuel filter hoses in the tank.
With these recent changes my AFR has dropped from 13.51 to 13.12 pulling from 3rd to 4th with N2O spraying. Target is 12.89 currently (N20 tune), fuel trims are all at 100 and injector duty is not tapped out (50-70 during spraying). Overall the car went from running lean at WOT to rich without N20. Leaving everything else to Seb @ specialtz to figure out.
Well it's been a journey to get this far and I have to say this was a huge success! The day started off with a Nitous refill gone wrong. I will not be bashing the business who made the mistake . They let me borrow one of their bottles since they empty my bottle instead of filling it up 15 minutes before my tuning session... Which I ended up macgyvering with my bottle pressure sensor on my other bottle. I also had a APS wire come lose when Seb @ Specialtz was trying to connect his knock headset / inline adapter into ECU for tuning. This threw us through a loop for an hour. I was able to make the repair on the dyno... After that we finished tuning for Nitrous. We ended up stopping at 402 whp, with a conservative map with only 26 degrees advanced @ 7200 RPM. Seb things we could hit 420/430 if we max out timing and spay to 7500 RPM with our are little 70 shot! Which could be done with e85. But we both decided it was best to see how the car does on the track first. All and all a 70hp shot resulted in 80whp and 100tq! Dyno results below.
Speical thanks to Seb @ Specialtz, Nitrous Outlet, and Deatschwerks for putting up with my craziness, providing outstanding support, and replacing parts without any fuss.
Next steps is hitting the drag strip!
Troubleshooting APS issues in the middle of getting it tuned... Had borrow a bottle of N20 ... Finally on the dyno, after 4 months of planning and prepping Dyno results NA vs 70 shot.
Last edited by jdog78; 10-03-2019 at 12:27 PM.
Reason: minor update
Today I changed my wheel color on my drag setup to Adamantium (Wolverine's claws color). This should be good for a least 10 whp and will strike fear to those that race me at the drag strip! I also filled up with some e85 that was almost 2 buck cheaper than premium. Got to love California gas prices... Tomorrow I am installing a few fans for additional cooling. Looking good New wheel color Old wheel color The good stuff Can't bet that...
So this mini-project turned out to be a success. This idea came to me while I was camping a few months back. I don't use the fog lights ever... Those fog lights each draw 35 watts @ 12 volts. So I did some digging and found some fans that run at 30 watts each on Amazon. Snipped the wires and rewired them to the fans, strapped the fans to the lower vented area of the grill for the time being. Now I have switched fans I turn on and off in the staging lanes! Install took about an hour.
Update: Relocated them to the stock intake locations. One is pushing air in and the other is sucking air out. This should help improve air circulation under the hood while sitting in the staging lanes. Where I had them before didn't do much, it was only place I could put them at the time... See last two pics for new placement.
Last edited by jdog78; 12-01-2019 at 09:45 AM.
Reason: Update
So I took my G out early last Sunday with drag radials on, prep the tires with a few burnouts with water. Launched at 1300-1500 rpm, the moment Nitrous hit at 3500 rpm my tires would just spin all the way into 2nd (not moving)... Once it hooked after going into 2nd, it still managed to hit 85-89 mphs in 8.2X - 8.3X seconds. Both runs I was breaking towards the end of the run. I am using draggy to capture my times. Screen shot below, you can see the acceleration just drop, speed go flat and breaking at the end. Yesterday I decided to reinstall my diff brace. I doubt it will solve this at all, but it couldn't hurt... The first time I had it on there, my diff started leaking. I later found out it wasn't sitting flat against the diff (bowing inward a little facing the diff). I hand sanded it down flat and added a washers to help disturb pressure points. I also added some locktite this time around to make sure nothing loosens up.
Thursday night I am hitting the 1/8 mile track in Irwindale. If I can hook when spraying I should have some pretty nice 1/8 miles times. I also plan on going this Sunday to Fontana. I'll be posting my time slips later this week. Wish me luck!
Results are in for the 1/8 mile. About what I expected with room for improvement. My biggest challenge is traction now. I am still spinning through the first few gears... I have a lot to figure out before Sunday's 1/4 mile drag. So far lowering my tire pressure to 19 lbs and lessening the spraying window (from 3.5K - 7.2K RPM to 4K - 7K RPM) help improve my times. 8.11 in 1/8! Not too shabby Wheel spin / acceleration dips
I am officially in the 12s now, only took 4 years to get here! Still in disbelief! I still have some traction issues (spinning into 2nd) and I need to work my 60 foot (they suck). The last few pass I tried manual shifting, which was a lot smoother than D or DS. If I can hit 2nd gear perfectly, I could knock off .20+ off easily. That's where I have a huge acceleration drop (ecu cuts throttle until rpm drops under 7500). But I was able to hit 12.606 @ 112.20 on my first pass, then a few other 12.6XX out of 6 total runs (testing other maps / AT modes, tire pressure and etc.).Two runs were against a gen six SS Camaro, took it down both times!!! See slips below and youtube links where you can see their number written on the side of their car. Man it was a great feeling taking down something that's stock 455hp / 455tq!
09-01-2019, 10:21 PM
Jdog's G37 RWD AT Sedan - Journey into the 12s (Nitrous Project)
. I am taking my car in next month to get it tuned with 70hp shot. Wish me luck!
Mission Accomplished
I also had a APS wire come lose when Seb @ Specialtz was trying to connect his knock headset / inline adapter into ECU for tuning. This threw us through a loop for an hour. I was able to make the repair on the dyno... After that we finished tuning for Nitrous. We ended up stopping at 402 whp, with a conservative map with only 26 degrees advanced @ 7200 RPM. Seb things we could hit 420/430 if we max out timing and spay to 7500 RPM with our are little 70 shot! Which could be done with e85. But we both decided it was best to see how the car does on the track first. All and all a 70hp shot resulted in 80whp and 100tq! 
