GC8 Engine Rebuild – Part 3

Life has become busy again, so this post is a bit late and lacking!

Dug the tiny torque wreck out and did all the camshaft caps.

Intake gaskets fitted and cam covers refitted.

Intake back on.

Putting the timing assembly back on

Cam gears back on.

Torqueing the cam gears to a crazy 98Nm…

Locking the gears for the job.

Covers back on and buttoned up.

Oil cooler, cleaned, flushed, then cleaned and flushed again!

Sump getting gooped and being ready to be fitted.

Sump and engine mounts bolted back on.

Legnum Major Service – Part 14

Getting closer.

Time to sling it back in the car.

Picked up one of those engine balance beams, but it’s chains were stupidly short, so I had to dig out some rustic chain from a box.


Lets do this!

Just need to clear the subframe with the alternator as well as the gearbox.

And it’s hanging!

Till next time.

Legnum Major Service – Part 13

Time for heat shields! Front all armored up.

Rear heat shields, all 4 pieces of it!

Magically the front timing covers, alternator and some other ends have appeared!

Adding the pipe work back on (this will bite me later….)

Fitting the thermostat housing and cross over pipe.

Finally, the cam cover rubber washers arrived so I could replace the old ones.

I might have lost a few of the bolts during this project…. On go some shiny 304 stainless bolts.

Looks spiffy.

Till next time.

Legnum Major Service – Part 12

Brand new brake lines arrived to replace they old assed stock ones which look like they have seen better days.

They fit really nice and look fairly factory.

Brembo’s looking spiffy.

Some copperlok nuts for the turbos and manifolds.

Rear manifold back on.

Turbo and gasket fitted.

Snugged up nightly, surely no chance of leaks now!

Fitting all the coolant and oil lines.

Dump back on as well.

Time to start on the front turbo now. Putting the heat shield back on for the oil filter dongle.

Turbo bolted onto the manifold, then loosely bolted to the head to allow a bit of movement to start doing up the turbo lines.

All buttoned up.

Till next time.

GC8 Engine Rebuild – Part 2

While the motor was apart, the missus decided she wanted to add some color to the engine bay.
Purple is her color and wow, engine bay is going to stand out now….
The cam covers have now been shipped off to get the same treatment.

A stark contrast when bolted to a filthy motor…

This has been a long time coming! Side feed injectors are hard to find decent upgrades for a most are not E85 friendly. I was looking to make my own rails using some universal fuel rail and TIG weld some tabs and spacers, but really, for the cost of the Radium Engineering conversion kit, it was just easier to open the wallet.

I had been keeping an eye on Raceworks 980cc injectors for a while as there are affordable (compared to the recommended Injector Dynamics injectors which are $1200/set!!), I priced them up at my local AutoOne who stocks them and they were $155ea. I decided to do one last google pass before committing and found that EFI Solutions was selling genuine Bosch 980cc injectors with plugs for $93ea! So in the shopping cart they went!

They are actually a 1/2 long snout injector with an adaptor over the snout to turn them into 3/4 length injectors.

They fitted perfectly with the Radium kit!

Next up I’ll be ordering some parts to make some -8 hoses for the fuel rails to the Turbosmart FPR1200 I have.
Till next time!

Legnum Major Service – Part 11

More parts arrived for the Legnum, so it was time to crack on.

New exhaust manifold gaskets.

Still awaiting new manifold nuts, so just a couple of old ones to hold it together for now.

New timing belt tensioner pulley arrived

Started aligning the timing and putting the belt on. I like to use zip ties to keep the belt in place as I go.

All done, several laps of the belt done and the tensioner pin has been pulled.


Looking forward to start buttoning this motor up now and getting it back in the car. Once I have the new manifold nuts and a couple of new copper washers for the banjo bolts on the turbos, they can all go back together. The thermostat hosing is looking like I will need to weld a new fitting on to replace the rusted one, more on that next time.

Legnum Major Service – Part 10

Time for the water pump.

Old on was pretty worn and leaking.

Pump gooped and bolted.

Timing gears back on. As I was bolting the new timing kit on, I noticed I was missing the new tensioner pulley that bolts to the hydraulic tensioner. Flipped the shed over and emptied all the random boxes but couldn’t find it, so I’ve had to order another one. This will delay this part of the job for another week or two.

With the timing belt stall, time to tackle some other small bits. Brand new plugs.

The coolant bridge pipe and thermostat housing is a mess and leaking, it needs a good cleaning and to find where the leaks are.

I found the source of one of the leaks, along with an old crunchy hose. I’ll have to decided if it’s worth reaming the old fitting out and welding an alloy barb fitting on.

Quick brake clean and a scrub of the lower intake manifold before plonking it back on.

Legnum Major Service – Part 9

Time to open another box of goodies to add to the motor.

Camshaft seals being fitted.

There front turbo was coated in grease and shit since the front cam cover gaskets were leaking, so I removed the front turbo and started cleaning the block, the oil filter mount and turbo drain

Some brake cleaner and a nylon brush to loosen all the shit up.

Looking better!

Clean Turbos!

Yeah…. I got a brake cleaner addiction >.>

Time for the cam covers. Spark plug seals and perimeter seal.

And fitted.

Legnum Major Service – Part 8

Picked up some ARP studs and kicked off the rebuild.

Started cleaning the pistons and deck

Studs in.

Head gasket on.

Unwrapped the heads and began preparing to slap them on.

Head on, ARP washers and nuts fitted, just needs torqued.

Time for the next side.

Cleaned and studs in

Gasket on.

Head on and washers/nuts fitted.

Dug out the old torque wrench and torqued the studs to spec.

GC8 Engine Rebuild – Part 1

Well the engine has been broken for long enough, I hummed n harred over various options and what to do with this (weighing everything up from a slap job to a $10k full forged rebuild) engine. In the end I decided it was time to dig out a spare bottom end (A $750 STI bottom end I picked up years ago for this situation), throw on some new head gaskets, ARP studs and send it. I was planning to service the block and heads, including some basic machining, but COVID and lock down has prevented me from transporting the parts over to my usual engine builder.

I missed a few photos at the beginning which mostly included me putting the motor on the stand and then cleaning a bunch of shit off it.

Motor on the stand, ARP studs fitted.

The deck cleaned up with the nylon brush.

Head gasket on

The head is filthy AF.

Lots of brake cleaner, razor blading and the nylon brush to clean these (this is half way done)

Head on

ARP studs torqued to 90ft-lb.

Cams back in for the short term, I need to order new cam cap bolts as a few are starting to round off and will likely fail to torque spec

Half the side done.

This head is also filthy AF.

So it got the brake cleaner, razor and nylon brush treatment as well.

Block cleaned

Head gasket on

Torqued to spec like the other side.

Cams added to that side as well and it’s starting to look like a motor again.

While the VF34 turbo is off the motor, it’s a good time to remove the P20 rear housing. (Legnum’s cute little TD03 rear turbo to the left)

I’ve had this smaller P18 housing ceramic coated and waiting for this opportunity. Hopefully we can reduce the spool down to the low 3000rpm range and improve the transient throttle response.


Till next time!