Cdv removal clutch delay valve OMG!

thanatu55 · Post by **thanatu55** » Sun Oct 22, 2017 11:51 pm

I currently have a Sprint Booster installed and set about mid way in race mode to negate laggy standing start. I don't race, it just helps it to set off like a normal car by adjusting the throttle response rather than clutch. Presumably without the CDV it would have the same effect but with much better fuel economy, and the Sprint Booster would just be a kind of 'sport' mode.

Smartbear · Post by **Smartbear** » Mon Oct 23, 2017 12:15 am

I’m not sure how removing the cdv could improve fuel economy? Tell us more

Rob

thanatu55 · Post by **thanatu55** » Mon Oct 23, 2017 12:19 am

I mean by not having to use such an aggressive throttle response as I am at present when moving from a standing start. Or not having to use the Sprint Booster at all.

Smartbear · Post by **Smartbear** » Mon Oct 23, 2017 12:20 am

Ahh!

Rob

thanatu55 · Post by **thanatu55** » Mon Oct 23, 2017 12:26 am

Basically I think I'm trying to say that because I already have a solution of sorts, I might not notice that much of a difference by removing the CDV, but it should be more fuel friendly and therefore wallet friendly!

kis · Post by **kis** » Mon Oct 23, 2017 8:29 am

Rusky wrote: ↑Sat Oct 21, 2017 6:36 pm Is the cdv on the SMG as it is a manual gearbox?

Glad you asked... lots of people commenting / threads about this ATM!

Post by **srhutch** » Mon Oct 23, 2017 9:01 am

thanatu55 wrote: ↑Mon Oct 23, 2017 12:26 am Basically I think I'm trying to say that because I already have a solution of sorts, I might not notice that much of a difference by removing the CDV, but it should be more fuel friendly and therefore wallet friendly!

Removing the CDV will have no effect on fuel. What it will stop is clutch slipping which is what the CDV induces.

thanatu55 · Post by **thanatu55** » Mon Oct 23, 2017 9:36 am

srhutch wrote: ↑Mon Oct 23, 2017 9:01 am
thanatu55 wrote: ↑Mon Oct 23, 2017 12:26 am Basically I think I'm trying to say that because I already have a solution of sorts, I might not notice that much of a difference by removing the CDV, but it should be more fuel friendly and therefore wallet friendly!
Removing the CDV will have no effect on fuel. What it will stop is clutch slipping which is what the CDV induces.

Again yes I understand, the effect on fuel would come from not using the Speed Booster as a means to negate the lag from a standing start that the CDV causes. With the Speed Booster set as high as it is at present it is bound to use up more fuel, for example; in an extreme case I could easily set off in second with it as s quickly as I could in first by adjusting the throttle resistance. Remove the cause of the lag and you remove the need for the Speed Booster.

Post by **srhutch** » Mon Oct 23, 2017 10:31 am

It really isn't going to make that much difference that you'll notice when pulling away.

aarsavage · Post by **aarsavage** » Mon Nov 06, 2017 10:43 pm

Was under the car the weekend, am I right in thinking my CDV has already been deleted?

Ducklakeview · Post by **Ducklakeview** » Mon Nov 06, 2017 10:46 pm

Hard to tell from that angle, but looks like it's gone, need a pic from the other side to be sure.

Mike

Ducklakeview · Post by **Ducklakeview** » Mon Nov 06, 2017 10:49 pm

thanatu55 wrote: ↑Mon Oct 23, 2017 9:36 am
srhutch wrote: ↑Mon Oct 23, 2017 9:01 am
thanatu55 wrote: ↑Mon Oct 23, 2017 12:26 am Basically I think I'm trying to say that because I already have a solution of sorts, I might not notice that much of a difference by removing the CDV, but it should be more fuel friendly and therefore wallet friendly!
Removing the CDV will have no effect on fuel. What it will stop is clutch slipping which is what the CDV induces.
Again yes I understand, the effect on fuel would come from not using the Speed Booster as a means to negate the lag from a standing start that the CDV causes. With the Speed Booster set as high as it is at present it is bound to use up more fuel, for example; in an extreme case I could easily set off in second with it as s quickly as I could in first by adjusting the throttle resistance. Remove the cause of the lag and you remove the need for the Speed Booster.

There is NO way you could get away as fast in 2nd as in 1st, especially in a 2.0, sprint booster or not. Those sprint boosters are a waste of time and money, all they do is "move" the throttle map, they don't make it any "quicker" you get exactly the same effect by pressing further on the accelerator. Try pulling away quickly in 2nd and you'll see exactly what the CDV does, the clutch WILL slip..

Mike

MrPT · Post by **MrPT** » Mon Nov 06, 2017 10:51 pm

aarsavage wrote: ↑Mon Nov 06, 2017 10:43 pm Was under the car the weekend, am I right in thinking my CDV has already been deleted?

Yes.

rally-chris · Post by **rally-chris** » Mon Nov 06, 2017 11:07 pm

thanatu55 wrote: ↑Mon Oct 23, 2017 9:36 am
srhutch wrote: ↑Mon Oct 23, 2017 9:01 am
thanatu55 wrote: ↑Mon Oct 23, 2017 12:26 am Basically I think I'm trying to say that because I already have a solution of sorts, I might not notice that much of a difference by removing the CDV, but it should be more fuel friendly and therefore wallet friendly!
Removing the CDV will have no effect on fuel. What it will stop is clutch slipping which is what the CDV induces.
Again yes I understand, the effect on fuel would come from not using the Speed Booster as a means to negate the lag from a standing start that the CDV causes. With the Speed Booster set as high as it is at present it is bound to use up more fuel, for example; in an extreme case I could easily set off in second with it as s quickly as I could in first by adjusting the throttle resistance. Remove the cause of the lag and you remove the need for the Speed Booster

You could try pulling away in second gear with loads of torque.....but don't expect your clutch to see out the week! The main reason that first gear ratios are set at the ratio they are in any sort of car is to manage the thermal energy of pull away, allowing for likely gradients that you might encounter. Most cars will pull away in 2nd but the thermal loading from increased torque load downstream of the clutch will quickly destroy a standard road car clutch if repeated regularly.

Chris

MACK · Post by **MACK** » Mon Nov 06, 2017 11:39 pm

Ducklakeview wrote: ↑Mon Nov 06, 2017 10:49 pm
thanatu55 wrote: ↑Mon Oct 23, 2017 9:36 am
srhutch wrote: ↑Mon Oct 23, 2017 9:01 am

Removing the CDV will have no effect on fuel. What it will stop is clutch slipping which is what the CDV induces.
Again yes I understand, the effect on fuel would come from not using the Speed Booster as a means to negate the lag from a standing start that the CDV causes. With the Speed Booster set as high as it is at present it is bound to use up more fuel, for example; in an extreme case I could easily set off in second with it as s quickly as I could in first by adjusting the throttle resistance. Remove the cause of the lag and you remove the need for the Speed Booster.
There is NO way you could get away as fast in 2nd as in 1st, especially in a 2.0, sprint booster or not. Those sprint boosters are a waste of time and money, all they do is "move" the throttle map, they don't make it any "quicker" you get exactly the same effect by pressing further on the accelerator. Try pulling away quickly in 2nd and you'll see exactly what the CDV does, the clutch WILL slip..

Mike

I don't understand why your trying to compensate for the cdv with a sprintbooster. Having a partially slipping clutch is still having a partial slipping clutch whether you use a BMW sport button (If installed),sprintbooster, remap
or even turbo/supercharge it. The clutch issue will still detract from the performance so you really want to fix that with the CDV removal rather than try to compensate or mask it in some way.

I don't understand why the sprintbooster gets such a bad rap. I can understand some loving and some loathing the sharpened throttle response. but what I can understand is why their sneered at yet It does to the throttle exactly what the BMW sport button does and folks seem to like that. In fact sprintboosters allow you an even sharper throttle response than the sport button does which really livens up the car. Its the same trick a lot of remappers employ on normally aspirated cars, thats why do many folks rave about their remap afterwards despite the headline gains being marginal. My biggest issue these days with sprintboosters is they've become so damn expensive, you might as well pay a little more for a proper remap.

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