James II - The lightweight ITB NB build
#1
James II - The lightweight ITB NB build
Hi guys!
Last summer I picked up an titanium headerback exhaust for a NB and decided to buy a car and make it as light as possible. I'm pretty far along and have already reached the 900kg mark with 2/3 tank of fuel. The weight savings are getting expensive as I spend every bit of free time to think of other places to shave off weight,
Here is a spec list of the car so far.
Engine:
Stock BP4W
Techno Toy Tuning ITB manifold
Toyota AE101 ITBs
Custom vacuum block / IACV
ITG JC50 domed sausage filter 100mm
ITG JC50 carbon tray 30mm
3D-Printed velocity stacks and gaskets
Skidnation coolant reroute
Rev9 coolant reservoir
MSLabs MS3 Basic
14point7 wideband
Innovative 60A Engine mounts
Supermiata lightweight 1.6 flywheel
Stock 1.6 clutch
MX5parts 42mm radiator
Boundary Engineering billet oil pump (2shims)
I.L. Motorsport oil sandwich
Oil cooler delete
Olive Ball Titanium header-back
Drivetrain/Misc:
Kaaz 1.5 way LSD
Duraflex 80A differential bushings
Power steering delete
Antigravity ATX20 battery
Suspension/brakes/wheels:
VST custom valved coilovers (from twguru over at miata.net)
Racing Beat front sway bar
949Racing end links
Keisler drop spindles rear
Rear sway bar delete
Duraflex 80A bushings
Titanium lug nuts
Wilwood Powerlite
Custom aluminium caliper bracket
MMP custom brake discs
Weds TC0-05 14x7 ET20
Toyo Proxes CF2 185/65-14
Interior:
Car Make Corns seats
Garage Star seat rails
Custom door panels
Nardi Deep Corn steering wheel
3D-Printed center console delete
3D-Printed shift ****
Manual windows
Polycarbonate side/quarter/rear windows
AWD "Into The Blue" cluster
Polycarbonate side windows
Polycarbonate hardtop window
Ididit Billet steering column
*GCFabrications GCR2 Rollbar
*GCFabrications door bars
Exterior:
Mazda Miata small Tupperware kit
Autokonexion carbon trunk
RX-7 FD APR mirrors with 3D-Printed adapters
Aerocatch hood latches
R-Theory tow hook with numberplate mount
Weight savings:
Part Weight reduced in kilograms
Soft top 20
Seats and mounts 14
Carpets 10
Doors 10
Exhaust. Ti header back 20
pare tire, jack, mounts 12
Center console/interior trim 5
Flywheel/clutch 5.5
Sound deadening 4
Front crash bar 3
Rear crash bar 7
Power steering delete 4
Steering wheel 2
Carbon canister 1
Air bag 5.5
Battery 9
Wheels. TC05 (10.6kg) 21
Lug nuts 0.7
Steering column 2.5
Hardtop latches 3
Lexan side/quarter windows 4
Stereo and speakers 3.3
Passenger seat 8
Lexan rear window 3
Total 177.5 kg (391lbs)
I picked up the car around summer 2020 and enjoyed it a fair bit with the stock 1.6 engine. But the heavy wheels and cheap coilovers made this a rather harsh and sluggish ride.
How it looks now. Fall 2021
Last summer I picked up an titanium headerback exhaust for a NB and decided to buy a car and make it as light as possible. I'm pretty far along and have already reached the 900kg mark with 2/3 tank of fuel. The weight savings are getting expensive as I spend every bit of free time to think of other places to shave off weight,
Here is a spec list of the car so far.
Engine:
Stock BP4W
Techno Toy Tuning ITB manifold
Toyota AE101 ITBs
Custom vacuum block / IACV
ITG JC50 domed sausage filter 100mm
ITG JC50 carbon tray 30mm
3D-Printed velocity stacks and gaskets
Skidnation coolant reroute
Rev9 coolant reservoir
MSLabs MS3 Basic
14point7 wideband
Innovative 60A Engine mounts
Supermiata lightweight 1.6 flywheel
Stock 1.6 clutch
MX5parts 42mm radiator
Boundary Engineering billet oil pump (2shims)
I.L. Motorsport oil sandwich
Oil cooler delete
Olive Ball Titanium header-back
Drivetrain/Misc:
Kaaz 1.5 way LSD
Duraflex 80A differential bushings
Power steering delete
Antigravity ATX20 battery
Suspension/brakes/wheels:
VST custom valved coilovers (from twguru over at miata.net)
Racing Beat front sway bar
949Racing end links
Keisler drop spindles rear
Rear sway bar delete
Duraflex 80A bushings
Titanium lug nuts
Wilwood Powerlite
Custom aluminium caliper bracket
MMP custom brake discs
Weds TC0-05 14x7 ET20
Toyo Proxes CF2 185/65-14
Interior:
Car Make Corns seats
Garage Star seat rails
Custom door panels
Nardi Deep Corn steering wheel
3D-Printed center console delete
3D-Printed shift ****
Manual windows
Polycarbonate side/quarter/rear windows
AWD "Into The Blue" cluster
Polycarbonate side windows
Polycarbonate hardtop window
Ididit Billet steering column
*GCFabrications GCR2 Rollbar
*GCFabrications door bars
Exterior:
Mazda Miata small Tupperware kit
Autokonexion carbon trunk
RX-7 FD APR mirrors with 3D-Printed adapters
Aerocatch hood latches
R-Theory tow hook with numberplate mount
Weight savings:
Part Weight reduced in kilograms
Soft top 20
Seats and mounts 14
Carpets 10
Doors 10
Exhaust. Ti header back 20
pare tire, jack, mounts 12
Center console/interior trim 5
Flywheel/clutch 5.5
Sound deadening 4
Front crash bar 3
Rear crash bar 7
Power steering delete 4
Steering wheel 2
Carbon canister 1
Air bag 5.5
Battery 9
Wheels. TC05 (10.6kg) 21
Lug nuts 0.7
Steering column 2.5
Hardtop latches 3
Lexan side/quarter windows 4
Stereo and speakers 3.3
Passenger seat 8
Lexan rear window 3
Total 177.5 kg (391lbs)
I picked up the car around summer 2020 and enjoyed it a fair bit with the stock 1.6 engine. But the heavy wheels and cheap coilovers made this a rather harsh and sluggish ride.
How it looks now. Fall 2021
Last edited by Teejay187; 04-02-2022 at 06:18 PM.
#2
The titantium exhaust showed below 3kg on the scales and it fits nicely!
I pulled the engine and interior and did a spit-shine over the winter while rebuilding an 1.8. I should have done the rings when I was in there lol. All sound deadening was removed and the interior and engine bay was stripped and painted. Doors were gutted, ECU was relocated, and only the most necessary things were added back.
Final revision of the ITB kit. 3D-Printed velocity stacks were made as long as I could get away with and still fit a decent filter.
Car at the scales. This was with 1/8 tank.
How it sits currently. At around 880-890 with 1/4 tank. I still got polycarbonate side windows and hardtop window to mount. Currently researching lightweight brake kits that fit under 14" wheels.
I pulled the engine and interior and did a spit-shine over the winter while rebuilding an 1.8. I should have done the rings when I was in there lol. All sound deadening was removed and the interior and engine bay was stripped and painted. Doors were gutted, ECU was relocated, and only the most necessary things were added back.
Final revision of the ITB kit. 3D-Printed velocity stacks were made as long as I could get away with and still fit a decent filter.
Car at the scales. This was with 1/8 tank.
How it sits currently. At around 880-890 with 1/4 tank. I still got polycarbonate side windows and hardtop window to mount. Currently researching lightweight brake kits that fit under 14" wheels.
Last edited by Teejay187; 10-10-2021 at 04:39 PM.
#3
As much as I enjoy IG updates, it is always a pleasure to see a proper build thread. Your weight savings so far are impressive; I am all about gram strategy as well, but I cannot live without some of the stuff you removed. Regarding brakes, I believe FM had something called "little big brake kit" using Wilwood powerlite calipers; a guy I know used to run 13" wheels on his NA using these. They will also save you a decent amount of unsprung mass. I would also look at brake booster removal (mainly for brake feel, but also weight). Presume you do not run ABS as well?
Care to give some feedback about your coilover setup? Not a lot of info out there (besides m.net), but the guy building these seems really knowledgeable!
Care to give some feedback about your coilover setup? Not a lot of info out there (besides m.net), but the guy building these seems really knowledgeable!
#4
As much as I enjoy IG updates, it is always a pleasure to see a proper build thread. Your weight savings so far are impressive; I am all about gram strategy as well, but I cannot live without some of the stuff you removed. Regarding brakes, I believe FM had something called "little big brake kit" using Wilwood powerlite calipers; a guy I know used to run 13" wheels on his NA using these. They will also save you a decent amount of unsprung mass. I would also look at brake booster removal (mainly for brake feel, but also weight). Presume you do not run ABS as well?
Care to give some feedback about your coilover setup? Not a lot of info out there (besides m.net), but the guy building these seems really knowledgeable!
Care to give some feedback about your coilover setup? Not a lot of info out there (besides m.net), but the guy building these seems really knowledgeable!
The coilovers have served me very well the year I've had them on the car. They're something completely different than the TA Technix, V-Maxx, BC and Maruha coilovers I have had. These respond well to setup adjustments. I could spend days and days just tinkering with the setup in small increments. Now it's a tad understeered on corner exit on partial throttle, but settles right down when I apply power and the LSD properly locks up. Plus they hold up well to the abuse I put them through.
#5
This weekend I aimed for reducing the weight by another 10kg, but I had to settle for around 7kg.
I started by removing the old hardtop window (which was a ******* pain in the *** with just a razor), clean up everything, apply Sikaflex 291i, and put in a polycarbonate window and quarter windows.
Stereo removed and some speaker covers I fabbed up. I was inspired by JDM aftermarket slogans when I designed them.
I started by removing the old hardtop window (which was a ******* pain in the *** with just a razor), clean up everything, apply Sikaflex 291i, and put in a polycarbonate window and quarter windows.
Stereo removed and some speaker covers I fabbed up. I was inspired by JDM aftermarket slogans when I designed them.
#8
I received the screen yesterday. High res and it seemingly works well. I'll get my hands on a Pi4 to start testing. Anyone running a CarBerry on their Pi with success?
#9
Got the race dash ready. I found a Asus Tinker Board laying around at home. Put a heat sink on it and now it is as responsive as a computer. I'm now only missing a mini-HDMI to HDMI-cable.
Started researching lighter brakes. It seems like I can get my hands on a set of ventilated 10 inch two piece discs and some super light calipers. The weight of the caliper, disc and adapter should be just over 9 pounds. That should net me a weight saving of 9 pounds each side in the front. Ordering up the parts next month to start building the kit. Long term the plan is to move from 14" wheels to 13" centerlock wheels.
Also wondering in anyone has a set of Xida dampers complete with springs that they could weigh? That should be the next low hanging fruit. My current coilovers are steel body and I'm betting the aluminium Xidas can save me tens of pounds.
Started researching lighter brakes. It seems like I can get my hands on a set of ventilated 10 inch two piece discs and some super light calipers. The weight of the caliper, disc and adapter should be just over 9 pounds. That should net me a weight saving of 9 pounds each side in the front. Ordering up the parts next month to start building the kit. Long term the plan is to move from 14" wheels to 13" centerlock wheels.
Also wondering in anyone has a set of Xida dampers complete with springs that they could weigh? That should be the next low hanging fruit. My current coilovers are steel body and I'm betting the aluminium Xidas can save me tens of pounds.
#11
It looks like the brake setup should clear 13's. Barely. Now to get the parts in house. Two piece rotors intended for a VW and GP320 calipers from Wilwood.
#14
Turns out i actually had the weights in my phone still.
Xidas: Race singles w/ dual springs and spherical hats
Billies: MSM shocks w/ dual Hyperco springs and Maruha hats
Rear Xida: 6.4lbs
Rear Billy: 8.6lbs
Front Xida: 8.0lbs
Front Billy: 10.8lbs
Xida total: 28.8lbs
Billy total: 38.8lbs
Xidas: Race singles w/ dual springs and spherical hats
Billies: MSM shocks w/ dual Hyperco springs and Maruha hats
Rear Xida: 6.4lbs
Rear Billy: 8.6lbs
Front Xida: 8.0lbs
Front Billy: 10.8lbs
Xida total: 28.8lbs
Billy total: 38.8lbs
I did the last weighing of the car after the last mods. Ididit steering column, polycarbonate windows with light bronze tint from plastics4performance, and passenger seat removed. Only fumes left in the tank and I'm right around 860. Now the car is parked for the winter and more extensive mods can begin.
#16
If it's strictly street use and will never be driven hard, more for show, then those brakes should work. You'll need a 205/60/13 tire to get the gearing right for a Miata.
Nice work so far!
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#17
I didn't see any mention of how the car will be used, but if it will see any sustained high speed or track use, those from calipers aren't really big enough for a Miata. Even a very light one. 1.03" pad volume is significantly less than stock. There is probably a Wilwood caliper with bigger pads that will fit your smaller rotor.
If it's strictly street use and will never be driven hard, more for show, then those brakes should work. You'll need a 205/60/13 tire to get the gearing right for a Miata.
Nice work so far!
If it's strictly street use and will never be driven hard, more for show, then those brakes should work. You'll need a 205/60/13 tire to get the gearing right for a Miata.
Nice work so far!
#19
So I decided to play it safe and get one of the Wilwood Powerlite calipers. On the scale they are 1.6kg / 3.5lb with pads. So around 2-3kg off the original caliper. And then the bracket should save some weight along with the 2-piece discs. If I can get close to 15-20lb saved in the front I'd be stoked!