Astra H VXR Sprint

The Odyssey lightweight motorsport battery came about for a couple of reasons. Firstly the battery on the road car died, and needing a battery for it in a hurry I ‘borrowed’ the Yuasa battery that was originally fitted to the track car.

So the option was to either replace it with another heavy wet cell car battery for about 50 quid or to justify the additional expense of a smaller much lighter weight motorsport battery. Simple choice really!

The Odyssey PC680 has enough capacity to run a 2.0 engine is much smaller than a ‘normal’ battery and weighs only 6.65kgs (despite the battery label stating 7kgs!), compared to a typical car battery at 16kgs or so. The weight saving is ideal, especially because of the additional oil cooler and pump that have gone in.

So, one Odyssey Extreme Motorsport Battery was ordered. The PC680 battery is only about 10mm taller than an original car battery meaning there is plenty of clearance on the bonnet and to make fitting simpler I specced it with SAE brass terminals to take the factory clamps, meaning no requirement to alter any of the cabling:

Odyssey PC680 Motorsport Battery

The next problem to be solved was how to mount the battery into the engine bay. There are plenty of functional battery clamps around for motorsport use for when a battery is mounted inside a vehicle, but very few visually appealing ones. Not wishing to have to make something from scratch, a search online discovered a hold-down clamp designed and sold by Odyssey.

Odyssey Battery Clamp

Unfortunately despite searching I could not find it available in the UK but not wanting to be defeated kept searching and found it available online in the USA so went about importing it. Possibly at US$110 it could be considered expensive, but I felt that for something well manufactured and ideal for the job worth every penny!

So I set about trial fitting the clamp and the battery into the car. The great thing with this clamp is that it sits on the factory battery support (which is integrated into the chassis leg) and the bottom left hole in the battery clamp lines up perfectly with one of the original M8 battery bolt fixings.

Odyssey Battery Trial Fit

To support the battery and clamp securely, Pro Alloy Motorsport made up a couple of additional supporting brackets to my supplied patterns. The first one, secures the bottom right fixing point to the OE pickup point on the chassis leg:

Mounting Bracket

The second bracket is a U shaped one and bolts to the clamp in 2 points and across onto the remaining pick up point on the chassis leg:

Mounting Bracket

All mounted securely, just the battery leads to be connected:

All Fitted – Just needs connecting up

And there is plenty of clearance between the battery clamp securing bracket nut and bolt closest to the chassis leg (which is at the top of the picture) and the clutch feed pipe which runs underneath just in front of the gearbox mount.

Clearance on Clutch Pipe

Over the winter I have decided to do something about the gearbox oil temperatures, which when on track can get seriously hot, one of the downsides of the M32 is its inability to dissipate heat effectively. So installing a gearbox oil cooler was the logical upgrade.

So why am I installing an engine oil cooler if the engine already has one? The simple answer is because the engine oil cooler is a small water cooled laminova core, mounted to the rear of the block just under the inlet manifold and cooled by the engine coolant. Whilst this is good enough at keep oil temperatures in check for fast road and track use at 280 or so bhp, potentially it will start to struggle more as more and more power is added, so worth looking at upgrading as well.

By installing a gearbox oil cooler I will need to add an additional external cooler. The thought process is to use the original laminova core (originally the engine oil cooler) to act as a gearbox oil cooler because the gearbox only has 3 litres of oil, so if I am adding an extra oil cooler I though I would make it for the engine and use a bigger external oil cooler because I am getting to the limits of the factory oil cooler’s capabilities. By doing this I am still only adding one external cooler (for the engine) and re-using the exiting engine oil cooler for the gearbox oil  rather than having to add two (one for the engine AND one for the gearbox.)

So after a conversation with Think Automotive here is the chosen Mocal Oil Cooler, more than adequate for a 2.0 Turbo engine:

Mocal Engine Oil Cooler

And a selection of black anodised aluminium oil cooler fittings:

Oil Cooler Fittings

also supplied by Think Automotive, who really know their stuff when it comes to this sort of thing.

I chose aluminium anodised over steel because I didn’t want any surface degradation and they look much better finished in black, albeit they are a more expensive fitting.

I also needed a selection of banjos and banjo bolts:

Banjos and Banjo Bolts

These are again aluminium anodised and somewhat expensive, however well worth the money (I couldn’t get them in black as they were out of stock and when I ordered them the lead time was too long). Supply came from Earl’s Performance in the UK, again very helpful. I chose these banjo fittings so that everything will screw together neatly. I did not want banjos with tails that have to be secured on with hose clips (however this type of banjo fitting is much cheaper in comparison!).

Finding somewhere to mount an additional oil cooler is great fun on an Astra where space is somewhat limited, but with the aircon condenser gone (it used to sit between the intercooler and water radiator) there is some available space. I mocked up the mounting brackets and then sent the Interooler to the guys at Pro Alloy Motorsport and asked them to fabricate some mounting brackets for the oil cooler, which would use Mocal rubber bobbins, and to also weld on a couple of additional bosses on top of the intercooler to securely locate the oil cooler.

And Pro Alloy produced four alloy mounting brackets:

Mounting Brackets and Bobbins

And a pair of bosses welded onto the top of the intercooler:

Bosses added to Intercooler

Top work as always from the guys at Pro Alloy Motorsport 🙂

Next was to start to make up the oil hoses and fittings. I am using Aeroquip push on or socketless hose, which has a temperature operating range of -40 to +150 degrees C. Fitting is very simple and pretty straightforward. Construction is AQP elastomer inner tube & outer covering with textile braid reinforcement finished in black.

Oil Hose Fitting

For the oil hoses I managed to track down some OE heat shrinkable fabric sleeve which is designed to protect from abrasion. Black Heatshrinkable Fabric Sleeving for additional oil cooler lines, to retain an OE look. Highly flexible heatshrink woven fabric tubing, Polyolefin/Polyester construction for excellent abrasion resistance 125°C operating temperature (excellent abrasion resistance to 135°C), Heat shrinkable to grip substrates tightly without additional fixing, Easy to install, Designed primarily to provide mechanical abrasion protection for components such as rubber hoses, plastic pipes and harness wiring bundles.

Heatshrinkable Fabric Sleeve

The easiest route for the engine oil cooler pipework is from the original take off plate above the oil filter and along the inner wing and past the headlight. This meant that the edge of the headlight housing had to be trimmed to give some additional clearance:

Headlight Assembly Modified for Clearance

Headlight Assembly Modified for Clearance

And then a suitable cover piece was cut from polycarb and painted black, then bonded onto the headlamp housing using RTV to give a water tight seal.

Cover Piece

The oil cooler pipework routed alongside the headlamp unit to the new oil cooler:

Oil Cooler Hose Routed Past Headlight

Oil Cooler take off plate which is thermostatically controlled to regulate oil flow to the cooler, with banjos and banjo bolts fitted with new oil seals:

Oil Cooler Take Off Banjos

And here is the oil cooler fitted to the top of the intercooler, just waiting for its pipework. The top 7 rows of the new oil cooler will get direct air through the upper grille:

Oil Cooler Mounted to Intercooler

Provision has also been made for an oil temperature gauge sender, which has been installed into the spare fitting at the back of the oil pump. I had the plug drilled and tapped to take a ⅛th NPT oil temperature fitting:

Engine Oil Temperature Fitting

More about this in the Oil Temperature Gauge post.

Courtesy of Pro Alloy Motorsport, I have a gearbox breather tank to add to the gearbox. Fitting one allows about an extra half litre of gearbox oil to be run in the gearbox, allowing for better lubrication and a larger volume of oil will dissipate more heat.

First the batter, and battery tray have to be removed. This give access to the top of the gearbox. The fill plug is removed and replaced with the supplied fitting to convert the fill plug into a breather point. Here it is fitted into the top of the gearbox. The second breather point can be seen top left of the picture:

8mm Fitting for Gearbox Breather

The breather tank is to be bolted to the bulkhead, so an M6 jack nut was installed into the bulkhead and tightened securely:

M6 Jack Nut Mounting

A hole was then made in the bulkhead sound deadening with a soldering iron to allow the bolt to pass through and into the captive nut:

Mounting Hole Through Sound Deadening

Both lengths of hose (one 10mm and one 8mm) were then measured and cut and then fitted to the two breather points with hose clips and then onto the breather tank on the bulkhead:

Gearbox Breather Points

And here is the breather tank bolted to the bulkhead:

Black Breather Tank Fitted

The OE radiator lower support brackets (minus rubber inserts – top) and the Pro Alloy Intercooler mounting brackets (bottom) have had a fresh coat of paint to tidy them up.

Radiator and Intercooler Brackets

Pro Alloy Intercooler (in Stealth Black finish) returned from Pro Alloy after having had the outlet (right hand top) opened up to 60mm from 50mm, plus the addition of a 60mm outlet pipe with map sensor boss (not shown).

Pro Alloy Intercooler

New Pro Alloy Water Radiator, in Stealth Black finish.

Pro Alloy Water Radiator

Black Intercooler Hoses to replace the original blue hoses, plus black alloy 90 joiner pipe (top left).

Intercooler Pipework

Water Rad fitted.

Water Rad Fitted

Water Rad and Intercooler fitted.

Water Rad and Intercooler Fitted

Water Rad and Intercooler Fitted

Water Rad and Intercooler Fitted

Intercooler

Track Spec Air Guide Blades added to the intercooler.

Intercooler Air Guide Blades

Air Guide Blade

Air Guide Blade

Fan Relays relocated to the water rad. They usually sit on a bracket on the front fan which sits on the air con condenser, which has all been removed for track work.

Fan Relays Relocated

The first thing to do is to get the bumper off and remove the intercooler and water radiator, zircon compressor and turbocharger.

Bumper Off

Intercooler Removed

Water Rad Next

Water Rad Removed

The intercooler is being sent to Pro Alloy Motorsport for them to modify the outlet to the new spec 60mm outlet. When it goes back together the factory water radiator is being replaced with a Pro Alloy enlarged water radiator, ideal for track day use due to the larger capacity thicker core all aluminium unit.