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The Ups and Downs of a 5 Speed Gearbox - Chis Laycock
 

This article is aimed at the Locust owner with an existing built car with a 4 - speed gearbox and a X-Flow engine. I have for sometime, considered replacing my 1700 X-Flow's 4 - speed gearbox with a 5 - speed box. The reasoning behind this was after several long trips on the Motorways, e.g. up to Stoneleigh etc. the engine revs at around 4000 rpm @ approve 70 mph. Now as we all know, the X-Flow engine is 30 year old technology, which in those days was never designed to operate for long periods at high revs on today's road systems.

Most of the Pinto engine Kit Cars, etc. go for the Ford 5 - speed box as it's a solid bit of kit which can take a bit of bhp, and can mate up with a lot of engines, but in this article I am dealing with the X - flow engine as this is in most Locusts. I must stress that I have NOT put the 5 - speed in my Locust, for reasons which I have stated at the end of this article, but I have gathered a lot of research on it, and are passing it on to you to make of it what you will. I hear that one or two of you are attempting to install 5 - speed boxes, and I am sure that any thoughts on the matter will greatly be appreciated by other club members on how you have done it.

Here is the 4 & the 5 - speed box side - by -side, taken from a top view so you all know what you are looking for.

The top gearbox is the 4 - speed, ( looks nice in it's new coat of paint ) and on the bottom is the 5 - speed box.( Not looking as good as the 4 - speed, I wonder what the inside is like? Still never judge a book by its cover or should that be gearbox.) The black thing under the 4 - speed box is a car jack.

Distance in cms. from front of Bell Housing 4 - Speed Box 5 -Speed Box
Overall Length 692 777
Speedo Output 380 610
To the centre of gear stick 648 730
Underside mounting point. 445 533

The box to fit is the "Type 9", Fords first RWD 5 speed box, based on the Type E. This is the most commonly used box for 5 speed conversions on older vehicles. Some versions were available with integral bell housings (same as the 4 - speed box ) although they are more commonly found with removable bell housing.

A 4WD version of the box is also available for the early XR4 x 4 models. ( Has any one build a 4WD Locust yet? The club would very much like to hear from you, pictures PLEASE.) You can find the Type 9 box in Ford Capri 1.6/2.0 up to 1983 and also the 2.8. Ford Sierra 1.6/1.8/2.0 up to 1988 also in the Sierra XR4i & XR4x4 2.8.

There is a TYPE N box which looks the same but is off a later Sierra, sorry no pictures and information on it yet, but it has different casing around the gear box area.

The 5 - speed box on side view, complete with oil leak. Good old Ford's they don't make um like this anymore. Still think it will fit in?

The Sierra is now about the most common place to find a box in a breakers and expect to pay about 60.00 - £125.00 and you take a chance on the condition. Most spares are available but you can also buy remanufactured ones from people like Mitchell Cotts Transmissions, Weston-Super-Mare 01934 428003 or Burtonpower.com, but expect to pay 400- 800.00.

There is also a hybrid 4-speed gearbox known as Type C or single rail fitted to early Sierras and also fitted to the Mk3 Capri with Pinto engines. The ratios are better spaced than the Escort 4 speed and the box is capable of taking more engine bhp. The box looks the same as the Escort but is longer and is distinguished by the bolt on bell housing as opposed to cast one piece, plus the gear lever is further back than the standard box.

So on to the Ups and Downs of a 4 or 5 speed gearbox. First, the argument FOR a 5-Speedbox.

1. As I mentioned above, to "cut down" engine revs on high-speed long runs. Fifth gear should reduce revs by 600 - 800.

2. To improve fuel economy. ( Is this really a valid " for" as most of us only drive our Locust's at the weekends. I know someone will write in and say "I use mine all week").

3. Your existing 4-Speed box is passed its sell buy date.

4. Now I'm struggling to think of other reasons, O I've just thought of another.... You want to carry on doing more work on the Locust, as a Kit Car is never finished off. There is always something you can improve on!

Now the argument against fitting a 5-speed box.

1. WEIGHT. The 5 speed is considerably heavier. The 4-speed box is 52 lbs, the 5 -speed box is 86 lbs.

2. The 5 -speed box is 3" longer.

3. The propshaft will need to be shortened.

4. The gear lever will be coming up through the transmission tunnel in a different place.

5. The 5-speed uses a 3 bolt pre-engaged starter, which means juggling around the starter to connect with the starting ring.

6. The 5 - speed main output shaft is a larger diameter with a different number of spines, 23 No. also on the input side you will need the clutch friction plate from the Sierra to match the Crossflow, also you will need the OUTPUT universal joint.

7. There are two types of boxes known as the Type 9 and the N type., with deferent input shaft lengths. The Type 9 has a 8.1" shaft length and the Type N has a 6.9" length. You will require a 1" spacer plate to fit between the bell housing and engine on the Type 9.

8. You will need to change the rear gearbox support plate. If you are buying from a breakers yard, make sure the plate comes with the box.

9. As the 5-speed box is longer and subsequently so is the bell housing, the drivers side footwell may well require shortening, with the lost of foot space. (Not good if you are over 6' like me).

10. The Speedo cable distance.

11. The Speedo cable will be very close to the chassis rails and may require a right angle drive adaptor.

12. The Speedo accuracy will be OUT, approx 14% over. I had my Speedo calibrated to my car which cost 50.00

13. Change the reversing light switch (if buy second hand from breakers) back to the one out of the Escort box. The sierra switch is different.

GEAR RATIOS 4-SPEED 5- SPEED
1st. 3.656 : 1 3.656 : 1
2nd 2.185 : 1 1.97 : 1
3rd 1.425 : 1 1.37 : 1
4th 1.000 : 1 1.000 : 1
5th N/A 0.820 : 1

14. As you can see from the chart, the Gear Ratios are slightly "taller" in 2nd & 3rd which in a 1300 engine might make accelerating slower.

There you have it. I have opted out of changing my 4 - speed into a 5 - speed.

Why...? I hear you ask.

If I was building the Locust from scratch, I could make all the changes to the body tub, welding up the gearbox support plate etc.
I also like the acceleration that I have with the 4 - speed box in top gear, and I also don't really do a lot of Motorway driving Lets faces it, with gull wings, and any thing over 75 mph, the Locust gets very exciting, specially when most of the roads are full of potholes, but that another story.

PS. If any Locust owners have recently put in a 5 - speed box, can you let us know in the club, or if you disagree with any of the above, I will not be offended.

PPS. I'm looking foreword to hearing from the builder of the 4WD Locust. See you all at some shows soon, and happy Locusting.

Chris Laycock.

 

 

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