ClubRoadster.net banner

mrpham's ITB build

Tags
dipstrap
116K views 533 replies 121 participants last post by  asng 
#1 · (Edited)
Hey all.

My previous car was a Nissan S15, built for track and street duties. Served me well but I sold so I could get an RX-7. Well instead of doing that, I've invested the money and bought an MX-5 instead. Should keep me entertained for the next 6 months or so, that's when I'll hopefully get my rotary fix.


Modifications so far:
  • 1.6L Engine from the NB6 (solid lifters, cam/crank angle sensors, etc...)
  • Extensively ported head
  • 280 degree camshafts with 10.5mm lift
  • Oversized valves
  • Stronger valve springs
  • Toda adjustable cam pulleys/gears
  • HKS headers
  • Toyota AE101 ITBs
  • Garage Star/T3 ITB adapter
  • T3 Velocity Stacks
  • UNI filters
  • Outwears filter booties
  • Innovate MTX-L
  • Relocated brake prop valve
  • NB 5-Speed gearbox
  • Lightened flywheel 3.5kg
  • Cusco 1.5way LSD
  • 4.778 diff ratio
  • Every nut and bolt re-zinc plated
  • Painted block
  • MegaSquirt DIYPNP ECU
  • Bluetooth ECU Connection
  • Custom ECU mounting
  • Toyota COPs
  • CNC cut COPs bracket
  • OBX dual feed fuel rail
  • Aeromotive FPR
  • Short shifter
  • Custom wiring harness, body and engine
  • FD3S RX-7 fuse folder
  • Dedicated engine fuse/relay panel
  • Flex-a-lite 16" thermofan
  • 42 Draft Designs Catch Can
  • GarageStar radiator cooling panel
  • 52mm aluminium radiator
  • MX-5 Plus custom exhaust
  • Yellowspeed Racing coilovers
  • Broadway Mirror
  • Frame Rail Braces
  • Low-Profile Headlights
  • Garage Vary front lip
  • Project-G Bikini Top
  • Carbon fibre side mirrors
  • Side Skirt Diffusers - http://omgpham.com/mx-5-miata-side-skirt-diffuser
  • R-Package rear lip
  • MX-5 Plus offset number plate bracket
  • Genuine hard top
  • Hard top brackets
  • KG-Works cluster
  • Vented front window
  • Momo Team 280mm steering wheel
  • Sparco Sprint V fixed back seat
  • MX-5 Plus Tall Boy roll bar
  • Whiteline sway bars
  • Genuine strut tower brace
  • Hankook RS-3 225/45/15 tyres
  • OG-San 15x8 +25mm with 5mm spacers to make it +20mm

My blog - http://omgpham.com/

How she currently sits (page 9):



 
See less See more
3
#100 ·
#103 · (Edited)
Re: mrpham's summer build

Build Update - http://omgpham.com/build-update

Not much has been happening but some updates for the build so far.

I received my first batch of Brake Cylinder Braces, so took some photos of what it looks like installed. It's too hard to take photos of the install, so will be doing it on a bare chassis in a few weeks.


Excuse my dirty engine bay.

I've also decided to ditch the old style CAS and go with dedicated crank and cam angle sensors. They're used in later model BP4W engines as well as NB6 engines.

Started my ECU harness too. Re-used the ECU connectors and just de-pinned the terminals so I could solder new wires on. Was a tedious process but well worth it, sensors/injectors/coils connectors will be installed later.


mmmm so fresh so clean.


Cleaned up all the connectors that I plan to re-use, de-pinned and bought new rubber seals.

Picked up this cool passenger foot well plate from MX-5 Plus. No idea what brand it is, but it looks useful as it'll give me more space for the MegaSquirt and fuse/relay panel.



Made a decision to get rid of the of standard coil/ignitors and go with the very popular "Toyota COPs". Coil-On-Plugs provide a much better spark as well as giving me sequential spark with the MegaSquirt.

 
#104 ·
Re: mrpham's summer build

ITB Assembly - http://omgpham.com/itb-assembly

The enamel paint on the ITBs finally dried, didn't air dry in 7-days like the instructions said. And I actually had it in the oven for a total of 12-hours at 60degrees. That was annoying...

Anyway, I had some time today so I went for a drive in search for new throttle plate screws. The factory screws are M3 which are "mushroomed" from factory to stop them from ever backing out. I drilled these out so I could pull apart the throttle bodies for sand-blasting and paint. Checkout the photos here - http://omgpham.com/itb-strip-clean.

The shop is called Small Parts & Bearings, they stock a huge range of screws and taps. Had a chat with them at the shop and they recommended the M3.5x0.6 Hex Cap screws. I bought the required tap too, total was $18. Not too bad I thought.


First step was to drill out the hole slightly and then tap the new thread.


Just test fitting the new screws, had to cut/shorten the screw too.


The assembly station, used a syringe to apply oil in the tight spots. Also picked up some spare ITBs for parts, was great having them there so I could check how everything went back together.


One throttle body done, three more to go.


All four throttle bodies assembled!

This next part is a bit hard to explain, but basically the Toyota throttle linkages don't really match up with the stock Mazda throttle cable. There's a bit of slack as well as not enough travel in the throttle pulley. The idea is to make more space between the throttle cable stop and the throttle linkages, this removes any slack in the cable. It's quite straight forward to do, just have to move some parts around so that the throttle linkages sit on cylinder #3 and #4 instead of #2 and #3.

After re-assembling the throttle bodies, the service manual outlines the procedures to adjust all four linkages that "daisy-chain" the throttle bodies together. I'll do that in the next couple of days hopefully.


I can't wait to get these on the car!
 
#106 ·
Re: mrpham's summer build

Nice work !
One comment on the screws you used though : the head is quite large and will generate some aerodynamic troubles.
I own a Mini. Carburetor tuning include shaving the head off (not entirely) and reduce the shaft thickness. Can you get some different screws ?
 
#108 ·
Re: mrpham's summer build

Nice work !
One comment on the screws you used though : the head is quite large and will generate some aerodynamic troubles.
I own a Mini. Carburetor tuning include shaving the head off (not entirely) and reduce the shaft thickness. Can you get some different screws ?
Thanks mate. Took your advice and got new screws in, will show you photos soon.

Those AE itbs are coming along nicely! What fuel rail are you going to use? Injectors? throttle linkage?
M-Tuned rail, 1.8L injectors and not too sure about throttle linkage setup yet. Will update as soon as I figure it out.
 
#109 ·
Re: mrpham's summer build

ITB Update - http://omgpham.com/itb-update

In my previous update I posted up about reassembling my ITBs. I had to use new screws to hold the throttle plates as the old ones were drilled out, they were replaced with socket cap screws but I was recommended to use something with a smaller profile head. I've now replaced the screws with button head socket screws.


The screws were also cut down so not much thread was left sticking out on the other side.

Spent some time over the weekend dialing up the ITB adjustment screws, still a few things to sort out and hopefully they won't cause issues down the track.



Stupid little adjusting screws, very tedious!


Finally received my FPR adapter piece for the M-Tunes fuel rail.


Gave the foot-well plate a good clean.
 
#114 ·
Re: mrpham's summer build

Wiring Update - http://omgpham.com/wiring-update

Small update... some wiring parts arrived and picked up a white board to help me scribble down wiring stuff. It's been pretty handy :D



According to the MegaSquirt manual, it's a pretty good idea to shield the TPS and trigger wires. So have been on the search for a flexible 2-core shielded cable, ended up deciding on a microphone cable from JayCar (part no. WB1530).



Terminated the shielding into it's own BLACK wire, this will grounded at the ECU end and left floating on the sensor end. The BLUE wire will be used for sensor return and the WHITE for sensor ground. The +5V/+12V wire will be run externally to the shield.



My awesome PURPLE (and grey) Deutsch connectors, all solid terminals too.


This is the relay block I'll be using, it's all modular so you can expand if needed.
 
#116 ·
Re: mrpham's summer build

Engine Harness & Wiring Parts - http://omgpham.com/engine-harness-wiring-parts

So a few weeks back I started working on the ECU/engine harness, this was re-using old connectors and terminals. Was never happy about re-using those parts...


How it was with the re-used parts.

Fortunately I was able to find the part numbers for new parts, all sourced locally from RS Components too! All parts are manufactured by Tyco/AMP and the part numbers are below:




I also found a very good source for automotive wiring in Brisbane, the company is CECA and located in Geebung. They stock Tycab's full range of automotive cabling.


All new connectors and terminals!



Also started on my Deutsch connectors, love these things!


All terminated... this connector is used for all coil and injector +12V wires.


As a precaution, I also did continuity checks for every wire and terminal used.


These are the parts I picked up to do my dedicated fuse/relay panel. Includes terminal bar, bus bar, fuse block and a relay block.


On the left are the brand new terminals I used, and the right is the FD RX-7 battery fuse block. This is where I'll be relocating all my main fusible links, sits on the positive side battery clamp.
 
#120 ·
#123 ·
Re: mrpham's summer build

Over the last week I've had a few parts cleaned up and also picked up a KG Works gauge cluster



Install photos are below...



So fresh so clean clean.

Since I'm going to be using the later model cam/crank hall effect sensors, I had my NB6 valve cover blasted and powder-coated in satin black. While I was there I also had the shop blast the NB6 water neck too, this will replace the NA6 water neck because I won't be using the fan switch. Megasquirt will control the fans now.

The work was done by Global Powder Coating, price was the lowest I could find and service/turnaround was good.


First step is to remove all four screws and the steering column surround.



There are two more screws holding the gauge hood, remove those and than gently pull the hood towards the rear of the car. It should pop out with little effort.


Unplug the two connectors at the back of the cluster to remove it.


The new cluster installed
 
#124 ·
Re: mrpham's summer build

My new fuel rail finally arrived, had to replace the M-Tuned rail because it had clearance issues with the fuel rail bracket. And I was able to get myself a B6 cylinder head for free. This allows me to test fit all the parts and I can work on the fuel lines and wiring while my NB6 head is away for porting and cams.




Also did a quick test fit of the ITBs to see if there are any issues that need to be sorted out.


 
#126 ·
Re: mrpham's summer build

Last week I posted some photos of my OBX fuel rail that I purchased to replace the M-Tuned one that doesn't fit. Well I picked up more parts over the last couple of days, things like braided hose and the required fittings. Just some notes on the OBX rail... it's utter ****! They didn't even bother deburring the holes or cleaning up any metal shavings left inside the rail, not to mention the threads were damaged!

All fittings and hose I've decided to source from Aeroflow, and I'll be using all -6AN sized fittings/hose for fuel. Purchased all the bits locally from Race Car Engineering, good prices and good service, would definitely recommend them.


My Aeromotive FPR (fuel pressure regulator), and fuel pressure gauge.


The crappy OBX fuel rail...


Some of the fittings I purchased, have more on order too.


Aeroflow's -6AN black braided light weight hose. This stuff is nicer looking, more flexible and easier to work with. Sick of working with the full stainless braided hosing, I like this hose
 
#127 ·
Re: mrpham's summer build

More Parts & No Progress - http://omgpham.com/more-parts-no-progress

Blehhh not much progress lately, BUT I have acquired some more bits for the build. Also been talking with a few guys who are also doing the same ITBs and we've found a few more issues with the T3 manifold... The issue is that the TPS is located towards the firewall and hits against the clutch master hard-line. This is not an issue for all the US guys who have the clutch master on the other side of the engine bay (LHD).


So that's the problem... there are possibly two ways to get around this.


So this is a solution that I'm going to test out, it involves taking 12mm off the end and machining the surface flat. So now I can use a banjo fitting that will let me clear the TPS.


The other solution is to use a braided hose like above, not sure if it'll clear the TPS though. Will figure it out when everything else goes into the car.

When I installed my new KG Works cluster I forgot to mention that my gauge hood also cracked. Was a pain in the ass but I was able to find a brand new genuine replacement . Apparently it was the last one in Australia too! Mazda have more on back order I believe.


So it looks amazing! It does't have the shiny finish like my old one but has a more smooth matte look. Will install this later on when I get a new dash to replace my cracked one.

The next part I found is a duct that is used in cars that don't have air-conditioning from factory. Since I'm removing my AC this part is perfect so that I can remove the ENTIRE AC system and still have functional air/heater.


Wasn't able to get a brand new one but Richard at MX-5 Plus was able to hook me up with this used part. Would prefer a new one but this is pretty decent.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top