EFI Rewiring: Bad vs Good Idea

Decided to overhaul my EFI wiring this week since it's getting on my nerves. Half of my injectors stopped working a few days ago, the fuel pump wires were smoking, the cable terminal block were melting and tonnes of other stuff made me sick and went to rip and re-did the whole thing.

Using terminal strips as wire junction, i gotta admit, was a bad move. Actually, it's not really that bad idea. DIYAutoTune, Megasquirt's official retailer, whose idea i copied, uses similar stuff on their MS Relay Board kit. It's actually nice that you can undo sensor wires individually with ease. The problem relies on your placement of the terminal strips under the hood. Here's what a bad location could do to your strips.

As you can see, those strips are melting all over the place. What's wrong? Here's what's wrong:

When i first placed the terminal strips there, i was still running NA. There's was no turbo to cause the extra heat to melt the strips. So, if you decide to go with terminal strips, make sure you plan ahead and place them away from exhaust.

I decided to get rid of those strips and use connectors instead. I can't find one rated for automotive use being sold near to where i live so i had to compromise with DB25 computer connector. I made sure it's placed far enough from the turbo. Let's see if it can withstand under-hood temperatures.

I also made sure correct wire thickness are used. When it comes to wire thickness, you can never go too big. Your limit is only space availability. No one would blame you for using 14 AWG on MAP sensor harness but that's overkill. On the other hand, 22 AWG on fuel pump or injector wiring? Be prepared for catastrophic failure. I'm going slightly overkill on the main power wire as it will supply all the EFI components, fuel pumps, injectors and ECU included. I even used a battery cut off switch so my EFI system is now separated from the ignition key turn. Here's the cut off switch, not yet mounted properly.

Nanung's 4A-GE 20v Carb'd Charmant

Nanung, i believe, is the owner of an autoshop called Ennergi Motorsport, situated in Jogjakarta, Central Java. This Charmant is a fine proof of what his workshop can do.

First, some specs:
- Fully restored body work
- Sikkens paint and clear coating
- 4A-GE 20v Blacktop head over 4A-C engine block. Fully rebuilt internals.
- Weber 45mm 4-barrels carb
- Crane Cams PS91 ignition coil
- Crane Cams HI-6 ignition module

Though going for carbs instead of retaining the EFI doesn't really tickle my fancy, i can honestly say i'm drooling all over the body work result. As a proof of how good the restoration work is, this Charmant won the "Best Retro Car" on Auto Black Through contest in 2010.

100,000+ Page Views! Woohoo!

Not bad..

Here's something to celebrate

Toothpick T50

I've been to online forums many times and read that T50 gearboxes as "strong" as toothpicks and will break even with a bit of harsh treatment behind a stock 4A-GE. Never really believed that.. until just recently. A few days ago, i went to Jakarta to attend my sister's wedding. It was about 250 km of driving with the 4A-GE boosted on stock TD04H actuator. This was The Dog's first long ride after the turbo was running.  At first, everything went smooth. I shifted at moderate to high RPMs under full boost, enjoying how easy it was to overtake slow trucks and old-men drivers. Hell yeah, turbo FTW!

Then, after about two hours, the gearbox started to sound funny.. whining and popping occasionally. Gears would suddenly turn neutral when decelerating. Three hours in and it just got worse, there was horrible gear grinding sound and shifting gears got even more difficult. Finally, just 10 about more minutes left before i reach home, the gear was stuck on 4th! There was no way i can get home now. Called dad and he helped me tow the car to the nearest autoshop. It was 4AM in the morning so the shop was still closed. I left The Dog in front of the shop and left a note.

At 8AM the shop called me. I lazily woke up of bed and took my spare T50 gearbox (Oh yes, i have one. Everybody should have a spare gearbox lying on their front yard, right?) and head to the shop. Explained what happened and they started the swap.

Here's the spare already in.

Here's the KIA box. Resting in pieces.

With me having no more spare T50, mini-project W5X series gearbox conversion has officially started. These W55-W58 gearboxes are much stronger than T50. The input shaft are about 50% bigger and best of all, they're cheaper here than T50s! I'm now on the phase of gathering ideas from online forums to find the best way to tackle this.

Budget Oil Catcher

Ghetto el-cheapo oil catch tank using old AC drier.

Manual Boost Controller

I have no idea what is the spring rate on my turbo actuator but since this is so cheap, less than 12 bucks to my door steps, bought it anyway. If the actuator spring's 0.8 Bar, then this is useless. If it's less, then it's good.

Oh, here's a little tip just to brighten up this boring post.

Close Enough

Result

The real deal