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Hank's GR Build - From an Engineer's Perspective

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31K views 105 replies 33 participants last post by  Hank  
#1 · (Edited)
For those that may not know, I have a similar build thread on FocusRS.org [here] and personal Build Diary website for my 2016 Ford Focus RS (weekend/autox). www.HanksRS.com.

This thread will be dedicated to my 2023 GR Corolla Circuit Edition (daily driver).
Follow along at my personal Build Diary website: www.HanksGR.com

Build Date History:
Build Date: 04/17/23
Arrived at Dealer: 06/13/23
Trailered home: 06/22/23, 06/23/23

Goals for my GR:
1. Bring a smile to my face each time behind the wheel.
2. Make total strangers come up to me and ask questions.
3. Run 12s in the 1/4 mile on 93 octane gas and street tires.
4. Survive weekend trips around the Louisiana countryside on its crappy roads.

Planned future mods:
1. More power
2. Tasteful weight reduction

Completed so far:
1. Window Tint (07/08/23)
2. First Detail + PPF (12/23/23)
3. Wheel Locks (12/27/23)
4. Blackvue Dashcams (12/28/23)
5. V1 Radar Detector (12/28/23)
6. Modern Spare Tire Kit (01/09/24)
7. LED Rear Bumper Reflectors (01/16/24)
8. Longer Rear Wiper (01/26/24)
9. Delta X Pitch Mount (02/02/24)
10. First Oil Change (02/02/24)
11. 2024 Model Year Updates (02/04/24)
12. Eventuri Engine Cover (03/10/24)
13. Eventuri Intake (03/10/24, 03/23/24)
14. ECUTEK Flash Tune (03/17/24)
15. ProClip Cellphone Dash Mount (04/02/24)
16. Forge Motorsport Intercooler Kit (04/06/24)
17. P1660-14 DTC Fix (04/23/24)
18. Delta X Pitch Mount V2.0 (06/15/24)
19. Ethanol Content Analyzer (07/14/24)
20. Front Bumper Fix (07/12/25)

Current Cost of Mods = $6,837.50 [Spreadsheet Link]

Current Datalog Results = ECU Connect App [Spreadsheet Link]

Current Certified Weight = TBD (x/x tank of fuel)
Current Race Weight = TBD (1/4 - 3/8 tank of fuel)

Current Total # of Launches (UniClutch Track) = 7 [Spreadsheet Link]
*Note: I never launched on the stock clutch. It slipped with my E30 tune and I replaced it.

Best 1/4 mile pass while modified:
12.703@110.92mph [Details Here]

Pictures along the way:
Trailered her home.

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#41 ·
Pictures along the way:
Eventuri intake installed. More information here.

Notes:
1) Undertrays don't need to be removed unless you drop something and you don't have a magnet retrieval tool.
2) Several wiring plugs need to be disconnected (MAF sensor, intake valve/flap, PCV sensor).
3) The factory airbox vacuum solenoid plug is disconnected and tucked away not to be used for the Eventuri intake.
4) Do NOT overtighten anything touching the carbon fiber. It is brittle and can be crushed!
5) Arrow on the MAF sensor points towards the firewall.
6) Total of (95) images on my personal build site with tons of information to complete the install.

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#43 ·
Pictures along the way:
Eventuri engine cover installed. More information here.

Notes:
1) Easy installation. Tug on the (4) corners of the factory engine cover. Swap over the (4) grommets from old to new cover.
2) Very easy to steal. I would not leave my engine bay unattended during a car show with this bling.
3) Total of (13) images on my personal build site with tons of information to complete the install.

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#44 ·
The intake is a pretty piece, but I think for that coin I would abandon the bolt-on-ability and instead extend that nice wide snout forward and under the radiator support cover to access a larger intake area of air from behind the grille and eliminate the path to underhood warm air. I understand that folks generally don't want to cut the cover though.
 
#45 ·
Pictures along the way:
DIY modified sunshade installed. More information here.

Notes:
1) Temporarily install sunshade. Mark interference with dashcam using sharpie marker. Trim sunshade. Sew black trim material.
2) Total of (17) images on my personal build site with tons of information to complete the install.

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#47 ·
I'm not sure the pictures reflect this very well, but the dashcam sits behind the modified sunshade. I had the same dashcam setup in my previous vehicle, a Scion iM, and had no issues with the 3M adhesive strip that Blackvue provided in ambient temps as hot as 100+ F. Mind you, the Scion had a much cheaper sunshade, but it still did the job.
 
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#49 ·
Pictures along the way:
Forge Motorsport Intercooler Kit installed. More information here.

Notes:
1) Several wiring plugs need to be temporarily disconnected in the front bumper (radar behind Toyota emblem, both fog lights, ambient temp sensor, and horn).
2) Note this installation is slightly different than a stock GRC because I already have an Eventuri intake installed. Your mileage may vary.
3) Total of (142) images on my personal build site with tons of information to complete the install.

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#51 ·
Thanks for the positive feedback. I went with the Forge Motorsport intercooler kit because it is very similar to the ETS fmic on my Focus RS. Not too thick, not too tall, and it comes with all of the piping. With some of the other GRC intercooler kits there are folks waiting months for the piping. I also like a stealthy, black fmic. No spray painted logos or shiny metal intercoolers for me please.
 
#52 ·
Preliminary datalogging results thus far. New Forge Motorsport intercooler kit is doing its job. Stratified keeps tweaking the 93 octane map. Will jump to E30/E40 soon.

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#54 ·
Pretty amazing thus far. Sent a few logs while stock. Then I added the Eventuri intake and sent a few more. This last tune revision includes the Forge Motorsport intercooler kit. Stratified has continued to tweak the 93 octane tune (final timing adjustments). Drivability is outstanding. This is my daily driver. Puts a smile on my face every time I'm behind the wheel. Feels like a mid 12 second car.

Absolutely can't wait until the E30 tune. My Focus RS picked up 40 lb-ft of torque and 42 hp (based on Cobb AP calculated numbers) switching from 93 to E30.
 
#56 ·
E30 or E40 is just a blend of E85 and pump gas?
For my Focus RS and my GRC, I will make E30 by blending E85 + 93 octane at a local gas station. Stratified lists E30 on his GRC tune video and dyno chart. Other tuners have posted they used E40. I'll update this thread with what he tells me to use since we're still on 93 octane tune revisions.

In this separate thread, I've been asking for anyone local to Boise, Idaho to let Fuel-It take a look at their GRC so they can develop an ethanol content analyzer kit. No takers yet.
 
#57 ·
Pictures along the way:
ProClip cellphone dash mount installed. More information here.

Notes:
1) Use the plastic trim tool (if necessary) to aid in tucking the ProClip mount on the driver side of the infotainment center surround.
2) Don't force anything. I had to send back the first ProClip mount as it was bent and cracked from the previous dufus trying to force it.
3) Be safe. Only look at your phone when there's a gap in traffic or it's safe.
4) Total of (21) images on my personal build site with tons of information to complete the install.

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#62 ·
Pictures along the way:
P1660-14 DTC Fix installed. More information here.

Notes:
1) This resistor may become warm/hot while the engine is running. Keep it away from anything combustible.
2) Existing air intake control valve solenoid resistance is 40.5 ohms.
3) New resistor resistance is 39.2 ohms with short wiring extensions soldered on.
4) R = V / I. R x I = V. 40.5 ohms x I = 12 volts. I = 12 volts / 40.5 ohms. I = 0.296 amps.
5) R = VxV / P. P = VxV / R. P = 12x12 / 40.5 ohms. P = 144 / 40.5 ohms. P = 3.56 watts.
6) Since the power required is 3.56 watts and the resistance is 40.5 ohms, I chose a 5 watt, 40 ohm resistor.
7) Total of (15) images on my personal build site with more information to complete the install.

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#63 ·
Pictures along the way:
ECUTEK Flash Tune started on 03/17/24 (still on-going). More information here.

Notes:
1) Before connecting to the ECUTEK dongle, your cellphone must have 20% battery or it will not start the tuning process. I plugged mine into the car charger.
2) The tuning process took about 12 minutes. Communication was tested to the ECU. Then CPU 1 and 2 were wiped and overwritten.
3) GRC Mileage: 2,368 miles on first tune (93 octane V1.0).
4) Will install E30 tune after 93 octane tune is finished.
5) Total of (17) images on my personal build site with more information to complete the install.

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#64 ·
Added the spreadsheet link below to my first post in this thread for my Datalog Results from Tuning. The link is also posted towards the top of the modifications page on my personal build site. Still tuning for 93 octane at the moment. After that is done, I will transition to E30. Flex fuel might be in my future if a kit is built.

https://hanksgr.com/HanksGR_Datalog_Results.pdf
 
#65 ·
Hank love the detailed tuning results you are posting and love your attention to detail on your build! Your car is performing very well from both the modifications installed and the fuel you are using - you have good 93 and we are very close to switching over to the E blends.

If anyone has any tuning questions, please don't hesitate to also reach out directly!
 
#66 ·
Stratified sent my first E30 tune file last week. I don't feel comfortable blending my own fuel without a gauge to monitor the ethanol content, so I ordered a Fuel-It universal ECA kit. It should come in next week. After install, I will monitor the ethanol content via Bluetooth. When ECUTEK has an update for flex fuel, I will connect that same ECA to the factory ECU via CANbus.
 
#72 ·
A few days ago when bad weather hit Texas, lightning struck the data center for my web server, killed power, and even took out the diesel backup generator too. Power was restored just a few mins ago. Try my site again.
 
#74 ·
Pictures along the way:
Delta X Motorsport pitch mount V2.0 installed. More information here.

Notes:
1) Follow the same instructions from my original pitch mount installation.
2) Torque was lowered ~20% on the OE subframe and pitch mount bolts due to medium threadlocker application.
3) Total of (14) images on my personal build site with more information to complete the install.
4) MUCH LOWER NVH compared to V1.0.

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#76 · (Edited)
Pictures along the way:
Ethanol Content Analyzer installed. More information here.

Notes:
1) Installed a Fuel-It Universal Bluetooth DIY Flex Fuel Kit for 5/16" fuel lines.
2) Purchased a factory low-pressure fuel supply line to scavenge the end connectors. Kept OE fuel line to reverse mod if needed.
3) Took 24 mins of idling after pulling EFI-MAIN No.2 relay and disconnecting HPFP wiring harness to stall, thereby relieving fuel pressure.
4) Total of (64) images on my personal build site with more information to complete the install.

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#80 ·
checked out the full writeup on your site. well done. you make this simple looking enough that I would feel good about giving this a shot. awesome work!
 
#82 ·
Finally found the sweet spot for calculating fuel level % when filling up to achieve E35 for my Stratified Tune. Unless I'm missing it, there is no parameter found through ECUTEK's datalogger for fuel level % like there is for my Focus RS via Cobb's AccessPort.

First, get down to 15-20 miles to empty.
Load the online calculator tool using your phone while at the gas pump = [LINK]
Gas tank size = 13.2 gal.
Gasoline Ethanol Percentage = 8. Tested local fuel with my ethanol content analyzer.
E85 Ethanol Percentage = 70. Tested local fuel with my test kit.
Target Ethanol Mix = E35.
Current Fuel Level % = 15.
Current Ethanol Mix = E37 (verified with my ethanol content analyzer).

Online calculator tool told me to put in 4.82 gal of E85 and 6.40 gal of 93 octane.
I put in 4.820 gal of E85 and 6.395 gal of 93 octane.
I drove a few miles and my ethanol content analyzer dropped from E37 to E35.