Donor Vehicle and Parts Required

According to Tiger, the Cat is a single donor kit car. This is actually untrue. The majority of the donor components come from one donor. However, a few parts are required from other vehicles as well.

The main donor vehicle is the Ford Sierra in either hatch or saloon (Sapphire) variant from any two wheel drive mainstream model. Though certain components from the estate or performance models can be used. The Sierra was introduced to the UK in 1982 (Y postfix) and replaced in 1993 (K prefix).

Throughout its life, the mainstream Sierra models had several engines fitted including the Pinto, CVH and DOHC. There were also several different manual gearboxes fitted including the 4 speed Type-3 and Type-E (also called to Rocket) and the 5 speed Type-9 (also called Type-N) and MT75.

For the Cat, Tiger recommend you use the Type-9 5 speed gearbox. Though, with a custom made prop shaft, there is no reason why any of the 4 speed gearboxes couldn't be used. The Type-9 gearbox was replaced across the model lineup in around 1988 by the MT75, though you may find later models with the Type-9. The MT75 isn't suitable for use in any of the Tiger models due to the size and location of it's rear gear housing.

When you are looking at a prospective donor vehicle, it is quite easy to tell which 5 speed gearbox it has without crawling underneath the car. On the Type-9, reverse gear is found by pushing the gear lever down, to the left and forwards. On the MT75, reverse gear is found by pulling the collar on the gear lever up, pushing the gear lever to the right and backwards behind 5th gear.

Once the gearbox has been identified, the choice of specific donor vehicle largely depends upon which engine you are using and whether you are going to rebuild the engine from your donor or buy a reconditioned unit. If you are going to rebuild the donor engine, you will need to look for a Sierra with a SOHC Pinto engine, ideally in either 1.6 or 2.0 litre guises as the 1.8 is more difficult to find tuning parts for. If you are buying a reconditioned engine or fitting a different engine, then the engine in the donor doesn't really matter as it will be replaced anyway.

With a wide choice of donor vehicles for low prices you can afford to be picky, though there are a few things to look out for:

• The 1.6 models have smaller diameter (8") and consequently lighter rear drum brakes than the 1.8 or 2.0 models (9").
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• It was widely believed that the 1.6 rear end was slightly narrower than the 1.8 or 2.0 rear end, but having since measured both, they are exactly the same width.
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• Some 2.0 variants have disc brakes at the rear. These aren't really required as the drums provide enough braking power, though rear discs do look good.
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• These however, are around 15mm wider than the drum braked models and may cause SVA problems with the rear wheels protruding from the bodywork.
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• More recent versions have front vented disc brakes replacing the solid disc brakes of the early variants.
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• Some models have an adjustable steering column. Tiger say this cannot be used, but at least one builder has managed to use it.

As I was fitting a Zetec engine, the engine in my donor didn't particularly matter and I managed to find a 1989 F registered Sierra 1.6 L (ie trim spec L) for £30 which had a 5 speed Type-9 gearbox and vented front discs as well as the smaller rear drums.

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Parts required

When stripping the donor, it us useful to have a bucket or box in which to put all unused nuts, bolts and washers removed from the donor. These occasionally come in very handy during later stages of the build. If in doubt about an items usefulness, and you have space, keep it, it can always be thrown away at a later date.

The following components are required from the donor vehicle, though I replaced many of them with new or reconditioned items during the build:

• Engine and ancillaries (if reconditioning donor engine)
• Gearbox
• Rear gearbox mounting plate (drill out rivets and keep centre section)
• Prop shaft (if not buying new Tiger prop shaft)
• Entire rear suspension assembly including diff, rear brakes, hubs etc.
• Steering column upper section including lock, stalks and wiring connectors
• Front hubs
• Front brake calipers, brackets and discs
• Track control arms
• Sierra pedal box assembly
• Master cylinder
• Brake regulator
• Handbrake
• Handbrake cable (if replacing, keep adjuster off old item)
• Windscreen washer bottle and pump
• Interior mirror
• Horn
• Gear knob
• Wheels (useful for moving the rolling chassis around)

The following components from the donor vehicle need to be exchanged with Tiger:

• MacPherson struts (front legs)
• Steering column lower section with rubber donut
• Gear lever (if using Tiger remote)

If you are using the Stuart Taylor floor mounted pedal box, you will not require the Sierra pedal box, master cylinder or brake regulator.