Welcome to Bamford Rose and it’s forum chat time. This week it’s yet more discussion about the twin plate clutch. Uninformed people turned car experts on forums, specialists who have zero clue what they’re talking about. If you’ve got a 4.3 or 4.7 V8 Vantage and you can’t be bothered to watch the rest of this video, then really yes there is no point. Just replace your single plate clutch with a twin plate clutch and jobs are good end off. This episode of clutch chatter was triggered by this buyer’s guide in this stated publication. Picked up a lot of criticism, saying that the buyer’s guide was pretty much a waste of time.
One poster said, ‘The buyer’s guide doesn’t include any costs, and even states that cars with upgraded clutches drive horribly and should be avoided. The guide doesn’t point out any of the common issues other than timing cover and gaskets.’ One poster then says, ‘The buyer’s guide was provided by McGurk’s who suggest not to change anything from factory spec.’ So, now the uninformed comment of twin plate clutch cars driving horribly starts to make a little bit more sense. Sales outlets make that comment of keeping the car standard, because they think that anything non-standard is going to affect them selling a car, that’s because the naive buyer is going to think that anything modified is bad and only the franchise dealer stamp in the service book is good.
It’s not until you spend five seconds within the Aston world that you realize that both of those are wrong. Look at any post which says, hey I’ve just bought my Aston, what are the essential things I should do and every man and his dog is going to be saying, ‘Delete the tracker, take out fuse 22. Upgrade your cats, remap the engine management system to get better drivability out of it. This is because the emissions devices are taken out and they always compromise drivability. So, we can delete those emissions devices, increase throttle responsiveness and get the car revving and responding and driving a bit better. And upgrade the single plate clutch to the twin blade clutch.’
For the sake of protecting your own wallet on selling a car, then saying keep the cars standard is really flogging a dead horse. Because that message really isn’t appealing to the audience of current buyers and current buyers are enthusiasts that actually want the cast to work for them. I can understand why some places might make comments like that. It’s because fundamentally they’re not engineers, they don’t understand evolving, they can’t do evolving. So, therefore that scares them and they can only really operate under the guidance under the mentality of a parts broken. Go to the shelf and get a new part, which is a direct replacement.
Look at all the cars in the private world being advertised and the ones trying to attract and do should attract a premium, are the ones that are saying, ‘Hey, I’ve got a twin plate clutch I’ve got a manifold and cat upgrade’. A list of evolution and improvement is being marketed rightfully as attracting a premium. That’s why any of these magazines that are doing a buyer’s guide, if they get in touch with notable sellers the buyer’s guide is going to end up being garbage. Bamford Rose channel is now close to 200 videos. There’s your buyer’s guide, not a buyer’s guide given by non-engineers who make comments to protect their bottom line. So, let’s talk clutches and let’s put a little bit of data to the discussion.
As this post says in the same thread, ‘My car is on 42,000 miles and so far, the clutch is okay. I will however be replacing it with a standard clutch as I don’t want the side effect associated with the twin plate clutch and light and flywheel.’ In terms of being able to modulate the clutch pedal, control or pull away get slicker interaction with the gearbox. Then the twin plate clutch hands down beat a single plate clutch and even beats a new single plate clutch. It’s true that a twin plate clutch and lightweight firewall can amplify increase a little bit what is termed as gearbox chatter. And this is pretty much the only downside. Gearbox chatter is the uneven firing pulses from the engine being transmitted down the torque tube.
Which acts as a megaphone and that results in the input shaft gearbox chattering. And when your foot is off the clutch in neutral maybe you can hear this slight gear chattering and below about 1500 RPM if you labor the engine say coming out of a junction or around about 1,750 RPM, the noise goes away like a switch. Now this problem affected standard cars and some cars standard drive in with no gear chatter whatsoever have the twin plate clutch and still have no gear chatter. Other cars will drive in standard quite noisy and be a tad noisier after the upgrade. In the aftermarket world, well here anyway we have a lightweight flywheel for cars that don’t gear chatter. And we have a heavier weight flywheel that mounts the twin plate clutch for cars that do exhibit gear chatter and the owner doesn’t want to increase that noise.
So, here gear chatter as a side effect is eliminated or is not downside of the twin plate clutch. Neither is there any noticeable increase on gear chatter on the factory’s own twin plate clutch upgrade, the AMR kit. But the AMR Kit has the same rotational inertia as a standard clutch, so you don’t get the improvement of throttle sharper on throttle responsiveness like you do with a lightweight flywheel. So, going back to the screenshot of this poster’s comment. I will be replacing it with a standard clutch. Well, let’s just sanity check that on price. You’ve got a 4.3 V8 Vantage and your clutch outer cover plate and friction plate is going to retail for 12 to 9.
You need a flywheel that will retail for 752 and you need a slave cylinder which will retail for 248. Give or take a few quid and with B80 that means that your 4.3 weak single plate clutch retails at 2,675. Let’s have a look at the AMR clutch kit. You get the flywheel, the clutch, the slave cylinder and with a V80 give will take a few pounds. That retails for 2,565. Now whether you fit an aftermarket upgrade twin plate clutch, which is arguably higher quality than the air market or you fit the factory’s own AMR kit. Just fit a twin plate clutch. By fitting a single plate clutch, you are actually spending more money than what you could buy the factory’s twin plate clutch for. And you are just continuing that cost down, that was applied to your car by the factory at point of sale.
The V8 Vantage was a twin plate clutch leading into production. It shared the driveline identical to DB9. The DB9 manual has the same gearbox, same torque tube and the V8 did have the same clutch and slave cylinder as the DB9 manual. As we’ve said in videos gone by that was cost down the single plate clutch came in and DB9 manual and V8 manual then had different clutch assemblies. At 2,675 for your single plate clutch, you’re paying more money than what it would be to buy the twin plate clutch from the factory. Whereas the single plate clutch is actually a cost out. The irony in that is just unreal. Just be careful where you get your twin plate clutch fitted if it’s outside the dealer network. When the dealer network opens that AMR clutch kit box there’s an envelope with a piece of paper in it, which is inviting them to log on to the dealer communication system. Put the car’s VIN number in that they’re working on and they’ll receive a config file back to download to the body module. Which takes into account the different inertia and the misfire monitoring that will be different on the twin plate clutch.
We go further than that here. And when we perform a twin plate clutch upgrade, we take away the unnecessary emissions devices on the car exhaust gas recirculation. This is where approximately 5% spent exhaust gas is put back through into the inlet manifold in an aid to reduce emissions. Well, we don’t need that to pass the annual MOT, that was only needed to sell the car. So, we can delete that feature, and when you get rid of that in a gas in the inlet manifold you know the gas has already been spent so it’s not going to combust for you. So, you’ve got 5% dilution of fresh oxygen which results in a bit of lethargic throttle response.
So, we have the lightweight flywheel increasing responsiveness, increasing the engine to rev up faster. We also take away those unnecessary emissions devices again improving on throttle responsiveness. And of course, we switch those diagnostic lights off which would indicate a problem with misfire. I’ve had a few phone calls from people that have had twin plate clutch upgrades done not here, not at a dealer network but somewhere independent somewhere generic. And I know those garages have not got the ability to remap with the body module. So, they’ve suffered some electronic crammings as a result of getting a clutch fitted by someone who wasn’t really capable of performing the job.
I mean just to go back to the comment where the poster says that he’s got 40K odd out of his current clutch so he’s quite happy with it and he’s going to carry on with the single plate. Now when that car was built with the flywheel and the clutch that that guy is using, then the components were probably straight and true. And 100% of the width of the friction material on the clutch. Friction plate was contacting the flywheel. He’s driven it in a very mechanically sympathetic way and he’s managed to get 40, 50, 60,000 miles out of it. You hear these mileages being accrued by some people. You then go and replace it with a new single plate clutch when it does wear out, but this time you’re really unlucky. You’ve got a flywheel which isn’t quite true, it’s a little bit distorted. And now it’s not contacting 100% of the width of the friction material.
I’ve seen this on lots of forum posts where people post pictures of their friction plate and you can see that there’s a very narrow band that is actually contacting the flywheel. There’s a big portion of the friction material, which is relatively unworn and not touched. And then you can look at a picture of their flywheel and the cover plate where the friction disc is running between and you can see that there are blue high spots on both flywheel and the cover plate. So, someone that’s got high mileage out of their clutch. If they’re unlucky to buy an assembly that’s not quite straight, not quite true is wearing only on a thin band of the clutch. Well, you could be lucky even if you drive it mechanically sympathetic to get half the mileage out of it. Because now you have got an assembly which is compromised.
That and even where is going to create heat that is going to create distortion and that is an ever-decreasing circle of wear. Ask one question on these forums and you get a million answers by people who are really not qualified in any way shape or form to make a comment. In that fog, it must be quite difficult as a new owner, new to the Aston world, doesn’t know what choices to make to decide what components are right for you. Any twin plate clutch design is superior to a single plate clutch design. So, if the factory were selling a twin plate clutch, it’s better than the single plate clutch. The factory retails their twin plate clutch 42565, they retail their single plate clutch for £2,675. No matter what you read on forums, those two pieces of information have to guide you to the obvious conclusion of fitting the twin blade clutch.
Hope you like that form of chat and we’ll see you on the next one.