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Frequently Asked Questions - Gearbox & Clutch
 
Flywheel weights
Clutch slave cylinder spacers
Information about gear change systems
Powershift set-up issues
Queued Gearshifts
How long does the air last in the pneumatic gearchange system?
Sierra 5 speed gearbox vs T5 Sierra Cosworth gearbox
Bellhousing and engine mounts for 2.0L XE in Ford Anglia
Spacer in the hydraulic clutch kit
Bellhousing for 1.6L Ecotec to Type 9 Ford rear wheel drive box
Clutch plates for Vauxhall flywheel & Ford Gearbox shaft
Spigot bearing for Vauxhall crank to Type 9 gearbox
 
Flywheel weights

Question: I saw about flywheel weight and I thought ask you one great doubt that I´ve seeing happening. For Standard cars, with standard car weight, I saw some guys with original flywheel and machined it to reduce their weight and Inertia. For the first gears, like 1º and 2º second, wow, what amazing acceleration! But at the middle of 3º gear and beyond we fill a slow acceleration. Top speed was also a problem, loosing significant km/h. They used to light up about 3 kg from a stand still flywheel with 11 kg. Do you have same idea that it works on a under weighted car?

Answer: The reason a road car has a heavy flywheel is for smooth running, particularly with low emissions where the engine runs lean.  The lighter the flywheel, the faster the engine can accelerate, this does not effect brake horsepower or torque in any way.  When at higher engine speeds and road speeds, it should not effect the engine's performance, if anything since the overall weight of the vehicle is reduced, in theory the car should be faster.

We only deal with motorsport and your problem could be caused by a poor lightened or balanced assembly or a management system that is detecting an error and therefore reducing the engine's performance.

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Clutch slave cylinder spacers

Question: I purchased one of these a while back.  Works great however I'm not sure I got the spacing right.  I noticed some slight scuffing inside the cylinder when I changed the seal.  What is the correct length of the spacers - or at least the difference in length of the 3 spacers?

Answer: There is no correct length a such for a spacer. The hydraulic slave cylinder set up is dependant on each installation. The way we normally set up our hydraulic clutch mechanisms is to assemble the clutch with no drive plate in, so in theory the fingers are as far back as they will go towards the gearbox as in a fully worn out state. We then fit a long spacer onto the hydraulic clutch mechanism, ensure that the release bearing is pushed back on the slave cylinder as far as it can go and then press the gearbox and bell housing against the back of the engine and measure the gap between the bell housing and the block. For example, if you had a 10mm gap, the spacer needs to be shortened by 10mm.

If the bell housing goes all the way against the engine, then you need to look through the release mechanism hole or inspection access of some kind and check the distance between the release bearing and the clutch fingers. If there is a gap when the release bearing is fully pressed as far back as it will go, remove the bell housing, pull the bearing and the slave cylinder forwards by slightly more than the gap you would appear to see through the inspection hole. Then reassemble again, this time the release bearing will be pushed back by the fingers as you assemble the gearbox onto the back of the engine until it stops. You can then remove the gearbox again and check the amount that the release bearing is proud of its stop. Then you will need to add this distance to the length of your existing spacer. This is not the overall length you need for your spacer.

Clutch Release Mechanisms

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Information about gear change systems

Question: I want to revisit the gear change thing. I'm looking on your web site and see: GEAR-PS-D-SHIFTER04 with Standard throttle bodies. Surely this will work on my new loom and change the gears up and down? Is this done with an electronic switch?

There are many systems out there, but it seems silly to have another system when the loom has the plug in option?

When you state on your site “Cable operated paddle” do you mean electric wire cable or Bowden type cable?

Please let me know if a simple system can be plugged into the loom as you state. I can make any suitable mounting brackets and if needed a gear flappy paddle! I assume it will operate from a couple of micro switches one for up and one for down?

Answer: I will give you a little bit more information on the gear change systems and how they work, then hopefully this will give you an idea of what can be done and what the pitfalls are if your system is too simple.

I decided to design a gearbox control system in 2003 and it was ready to run for the beginning of the 2004 season. When we initially tested the car, all seemed fine. But as we got to the first event and subsequent events we discovered the gear changes were becoming erratic and as the season progressed, the changes got worse and worse. I looked at the systems before designing ours to see what everybody was doing and assumed that a Gearchange was simply a question of cutting the spark and then pushing it from one gear to the other. At the end of the 2004 season I removed the electronic system and put a manual system onto the car, similar to that you have seen on our web site using a cable or rod operated system which was connected directly to the gearbox. I logged all the information over the season to discover what was going on. We found out that no two gear changes ever take the same amount of time, no matter what the conditions and if the vehicle happens to be wheel spinning, gear changes take even longer. When you are driving with a gear stick or gear lever or anything where the driver or rider is connected directly to the gearbox, without realising every time you carry out a gear change you actually subconsciously adjust the way you change gear, whether it be foot or hand operated clutch. So when you produce an electronic system to reproduce this, a simple system which we had originally come up with is not capable of doing this. If you simply put a long time for the spark to be cut and the gear changes faster, the gear changes feel as if they take forever and if you put a short time in there, quite often a gear can be missed and the gearbox will become damaged if not straight away over time. So we very quickly learnt that you need to produce full closed loop system which works out drum rotation of the gearbox and therefore the time for the power reduction of the engine can be varied according to how fast the gear change occurs. Therefore making a self-adjusting system. This is just a basic explanation of how it works. Our system is actually considerably more complex than that, so it can actually work out if the gearbox is actually going to change gear, what to do if it doesn’t want to change gear and so on. Next comes the mechanism that you are using to change gear. When you change gear with a bike or car gearbox, you never actually kick it into gear, or smash the gear stick into gear, you actually feel it going into gear smoothly. So the system you use to carry out the gear change needs to be able to give a gentle, yet precise and smooth operation without damaging the gearbox itself. It is not a question of how much power or how fast you can move the stick, as you would simply damage the transmission.

I spent a further 5 years designing and testing our system, so that now that once it is set up it can self-adjust to suit most gearboxes. But this involves quite a few complex components and a powerful ECU that controls not only the engine but the gearbox itself. In fact to give you an idea of how complex it is, if the system senses that the gearbox does not want to change gear, due to the fact that the dogs are jammed or locked for any reason, because the ECU that controls the engine also controls the gearbox, it can do very precise control. So sometimes it fires one spark or removes 1 spark in order to unlock the dogs. This would be impossible for a piggy back system or ECU as it cannot know when each spark is going to be delivered. There are a few high quality systems available on the market which are extremely good, but they are not cheap. The simple system that is listed on our web site which uses the original gear stick of cable is a fairly basic design and allows you to go for faster gear changes, but because of the driver actually being able to feel the gear changing through the lever or paddle, this adjust how the gear change occurs. Any system that is fully electronic e.g. where the driver is not directly connected to the gearbox, would need to be a closed loop design to function correctly in all conditions. With a simple system that simplifies a solenoid or actuator has its limitations and maybe ideal for use with a driver who is disabled or for casual driving where the user understands its short comings.

This is why we only produce the two types of system. Either one where the driver is still directly connected to the gearbox by a mechanical mechanism or a full gearbox control system. Hopefully this all makes sense. If you read through the frequently asked questions for the link to the system you have been looking at, you can see that they state what can and can’t be done with our system.

Gear Control System

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Powershift set-up issues

Question: One of our trade customers was having problems with a powershift set-up on one of their customers cars and asked for some help, he had set up the map using the settings from another car which has worked well.

The car was an Escort with a VX and Elite IL300 box and the description of the symptoms was; "Just been out in the car and it still isn't working correctly, it's very harsh when it comes back on power, not a nice smooth cut at all. It all seems too harsh and needs smoothing out. The setup is just using an ignition cut, cutting the spark, so it's very on and off. The setup allows for torque reduction + recovery, can you tell me a bit more about these settings and also why these aren't been used? There isn't any information available about the MBE settings and if I fiddle with them without knowing their functions, it will end up causing issues."

He also asked: When we have spoken in the past you said you had not found the need to use the torque recovery and that ignition only worked very well.  Hence my using the same options. Could you provide any advice as to possible solutions.  I notice on the paddle shift set ups I have looked at the "Finish Upshift Drum Rotation Threshold" is at 70% but on the flatshifts its 100% - could this be the issue?

Answer: Always make sure you are using the latest software, please check our website.

I suspect you have 2 potential issues; the first problem will be how the power shift is triggered. Quite often some of the gearboxes have an adjustable switch or sensor and what the manufacturer quite often does to ensure the powershift works is to make the switch trigger too early. This means that when the gearstick is pulled that instead of triggering just at the point of disengagement, it is triggered much earlier, this effects both single cut time set ups and full closed loop set ups. When used in the single cut time, it means that the time has to be extended to cover the fact that when the driver pulls the gearstick, there can be quite a length of time from the spark being cut before the dogs of the gearbox are actually disengaging and by the time the gearbox has completed its change, the driver will be able to feel this huge delay making for quite often and uncomfortable gear change. When using the closed loop version the same issue applies, the trigger again will be too early and although the gear change time is able to vary due to the ECU knowing the drum position and able to complete the gear change when it reaches a pre-programmed position, it is extended due to the early trigger.

In order to alter the trigger point, you will need to discuss with the manufacturer of the gearbox how this is done and experiment with the trigger point according to the manufacturer's instructions. This could be done by shims or adjustable screw to move the switch.

Once you have sorted the start point, then you will be able to adjust the cut time if using a single cut set up but because no gear changes are ever the same, care must be taken not to shorten the cut time too much. A single cut is also not suitable for cars that could potentially be wheel spinning during gear change.  It is always best to use closed loop set up using the trigger to initiate the gear change and drum rotation to complete the gear change. This way the MBE system self-adjusts to the variation in time taken for each gear change.

Due to the fact that every manufacturer of gearbox works slightly differently, therefore the gears drum rotation will also vary. You should experiment with the percentage of drum rotation for completing the gear change.  When set to 100%, the power will only re-instated once the gearbox drum has completed its rotation. You can experiment with shortening this value and it will speed up the gear change. Again great care must be taken if the value is set too low, although the gear change would become very fast, if the dogs have only just engaged there is a possibility that damage will occur due to the fact that the power is being re-instated too early. We find that most car gearboxes can go down to 70% of drum rotation and bike gearboxes down to 79%, but it is suggested that you start at 100% and slowly reduce this value due testing.

The difference between cut and retard; cut simply removes all the sparks and retard will retard the ignition so the engine produces no power. Cut is simpler and if all the above are set up correctly, the gear changes should be very nice. If you use retard, it can be smoother but produces other issues; whilst retarded the engine will be producing more heat and if the engine itself is prone to any issues, it could amplify an inherent problem with the engine. Also when the ignition is in a retarded state, the fuel is no longer ignited in the combustion chamber, it will be ignited in the exhaust producing additional noise because of this. A combination of cut and retard can be used but more information, as far as suggested settings are concerning, are within Easimap 6.

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Queued Gearshifts
Question: Does the MBE have an option for queued gearshifts?

Answer: We did consider adding an option for queued gearshifts but have not found it necessary, most drivers who have used our system including those converting from other makes of gearshift systems find ours usually faster on the shifts (mostly due to the integration of engine and gearbox software) and not thought it necessary once tested. My own personal thoughts on queued downshifts is that when you approach a corner, if you don't know what gear you want you would just keep tapping the paddle hoping you would get enough downshift. If you do know which gear you want, you again have to think how many times you have to hit the paddle, if you then approach the corner and something has changed you may have to hit the paddle for more gear changes. All of the these options require additional thought by the driver and these thought trains will be different based on the discipline you are competing in, simple pull and hold means it will only change down safely and if you let go of the paddle, it will stop changing down. If you simply want one gear change, you tap and release the paddle. I have found that if we attempted to queue the gears, if it wasn't safe to downshift when the paddle was hit and a change occurred later, this was very distracting for the driver and he didn't know what point the change would occur. This was particularly uncomfortable if an unexpected gear change happened when the driver was making an unexpected change in direction avoiding another car or obstacle.

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How long does the air last in the pneumatic gearchange system?
Question: How long does the air last in the pneumatic gearchange system?

Answer:The valves used are an industrial design and will slowly leak air over time (as used by everybody). Air loss varies depending on many variables, but I would normally suggest a minimum would be about 2 hours from fully charged and normally fully discharged by the next day, although I have seen cars hold air for over a week. There is no fixed time. I am always paranoid that the air will run out on a run and because of the noise in the paddock you cannot hear air leaks at the event, so I charge the air on my car after every 1 or 2 runs to ensure it never runs out.

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Sierra 5 speed gearbox vs T5 Sierra Cosworth gearbox
Question: I'm looking at replacing the engine in my Mk II Escort from a Ford Pinto Engine to a 2 litre red top. This is going to be a road going vehicle also to be used on track days. It's currently running a 2 litre pinto and a 5 speed Sierra gearbox. I also have a 5 speed 2 wheel drive Sierra Cosworth gearbox which I would like to fit with the red top engine if this is possible?

Answer:We would always recommend the Sierra gearbox you are already using as this is the most common fitment on the XE conversion, it has the widest range of components available, not only for fitting of the gearbox but also if you upgrade later on you can either replace the internals of your current gearbox easily with a range of gear kits available or a large choice of specially manufactured gearboxes which are designed as bolt in replacements in H pattern or sequential form. The problem with the T5 gearbox is that there is only a limited number made, the installation does not have as many components available and the gearbox itself was never ideal and when I used to drive a Sierra Cosworth, this was the first part that was thrown away.

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Bellhousing and engine mounts for 2.0L XE in Ford Anglia
Question: I want to put my 2.0XE (running carbs) into my 67' Ford Anglia 105e using a straight cut/close ratio 4 speed Ford box. Can you please advise me on the correct bellhousing, engine mounts and anything else you produce that I would need?

Answer: We would recommend the same components as people use for the Escort. We have at least a couple of customers using the Ford Anglia with the XE engine in. Both have gone two different routes, one has used the vertical bellhousing and the other has used the 7 degree version (as listed on our web site). The vertical bellhousing means the engine sits bolt up right, but this makes the carbs come very close to the inner wing. You would then require to run very short air horns which would mean your engine sacrifice quite a bit of power. Also the sump pans that are produced normally come from the Opel Manta or Carlton and these are designed to sit at 7 degrees, so you would also need to fabricate a sump. I would suggest you use the 7 degree bellhousing, this would give you more room for your carbs and a wider choice of sump options. I would suggest the chassis mounting kit for your engine mounts and this will allow you to position the engine in the best place and these mounts give you that freedom.

I would look at the club spec exhaust manifold, which is designed for the Chevettes and Escorts and you can look at the many components listed for Escorts. These will in many cases suit your installation.

Links: Bellhousings | Engine Mounts | Exhaust Manifolds

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Spacer in the hydraulic clutch kit
Question: I have a problem with my Westfield. It seems like the car is riding the clutch when you put your foot down. It drives fine at normal speed, but when you floor it you just get engine revs. I have a SBD Standard size lighten flywheel, (the one with posts, a SBD Organic clutch and a SBD hydraulic clutch kit. Some one suggested that as I have been using the car the clutch has worn down so now the spacer in the hydraulic clutch is no longer the right size. So the fingers of the clutch cover do not have the space to come away fully. So do I need to remove the engine and get the spacer removed? Can you offer any advice to me? I have tried bleeding the clutch and it did not help.

Answer: It sounds as if you are half right. When the assembly was fitted, no account was taken to allow for clutch wear. You must dry fit the clutch cover with no clutch plate fitted, then slide the gearbox with the complete slave assembly and spacer fitted to the gearbox. You should then slide the gearbox onto the back of the engine. Now because the spacer is likely to be too long, you should be able to measure a gap between the block and bellhousing face. Say for example, it was 10mm, the spacer should be shortened by 11mm. This means that when the clutch is fully worn the slave cylinder/release bearing can never apply pressure to the clutch fingers. The extra mm is just a safety margin I always use.

Never leave the spacer out altogether, because the clutch slave only has a certain amount of travel. If you were to leave the spacer out completely, the chances are you could fire the hydraulic slave so far out that all the fluid could leak away.

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Bellhousing for 1.6L Ecotec to Type 9 Ford rear wheel drive box
Question: I need a bellhousing to take a 1.6L 16v Ecotec to type 9 ford rear wheel drive box, is it the same as the 2.0L 16v engine?

Answer: Yes, it’s the same as the 2.0L version. We stock four types although only two are really suitable for you installation. They are either 150mm long for the standard length input shaft. We do 170mm long version, which is for the longer input shaft, normally used on the V6 ox (this helps with gear stick position).

Links: Bellhousings

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Clutch plates for Vauxhall flywheel & Ford Gearbox shaft
Question: Do you have clutch plates to fit the Vauxhall flywheel and Ford gearbox shaft & what bhp would the standard pressure plate cope with?

Answer: We produce several different versions of clutch plates for use on the Ford gearbox. The simplest one is a 200mm Kevlar clutch, which has up-rated material and springing with an 1" x 23 spline is a CLT-70-4628. We normally recommend this to people who are fitting the engine into a lightweight car such as a Westfield. We usually reckon it can cope with about 200 - 210bhp in a light car. if you are putting it into something like a rally car, we would recommend you have a paddle type version CLT-76-4628. This has the similar design, but with the up-rated material but still has springs to absorb the shock loads.

Links: Clutch Introduction

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Spigot bearing for Vauxhall crank to Type 9 gearbox
Question: Does the Vauxhall Crank need the spigot bearing machining to fit a for type 9 box?

Answer: Yes, you do need a Spigot Bearing, The type you need go in the end of the crankshaft is CLT-SB1. Due to the fact that the recess in the back of the standard 16V crank is quite short you may need to grind a small amount off the end of your spigot shaft to make sure it does not run aground on the crank.

Links: Spigot Bearing

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Please check our customer cars section which may help answer your questions
 
2.0L Vauxhall Components | 1.4L & 1.6L Vauxhall Components | Duratec Components | Hayabusa Components

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