TLDR: I'm looking for a solution to have valves fully open all the time like pulling the fuse in the old Vantages. Does something like this exist?

I have Velocity AP Secondary Cat Delete on my 2020 Vantage. I do notice some improvements in sound, mainly idle burble is a bit more present, but it's a pretty subtle change and I'd like even more volume. My stock GT350R and wife's 2014 Cayenne NA V8 GTS with secondary cat deletes make the 2020 Vantage sound a bit like a pussycat. I fully understand Aston's are not designed to be "overly" loud, but the heart wants what the heart wants...

It does seem, and the manual says this as well, that there are three stages of valve opening in relation to Sport/Sport+/Track modes. I prefer the general driving characteristics for commuting of Sport+, but really prefer the sound level that Track mode offers. I understand the pops/bangs and downshift blips (which I enjoy) are a factor more so of the much higher rpm Track mode keeps, but Track mode seems louder across the board to me. So are the valves less open in Sport+ than track? Listening near the pipes at idle, it seems to me that gasses are always flowing through all four tips, so it's never really a straight pipe option from the cats back and the valves are only partially diverting flow away from the mufflers?

I find that Track mode offers my preferred exhaust note/volume, but I don't always want to use the paddles and track mode holds gears too long for most street use (ie don't love holding 4,000 rpm on a long 35mph road if I'm holding a cup of coffee in one hand just to get the desired exhaust note).

I'm looking at Velocity AP's exhaust option https://www.velocityap.com/product/aston-martin-vantage-amv8-2018-on-4-0tt-valvetronic-exhaust/ but $3k is a big chunk of change and I have to pull the bumper off to install it for what I'm presuming is not very much gained in volume since it's still valved and controlled by the car's computer (if anything the X pipe quiets the volume a bit while smoothing the tone / plus the mid pips already had two H pipes stock). Unfortunately, Velocity AP cannot keep the valves open at all times via their tune option.

I guess what I'm really looking for is a solution to have valves fully open all the time like pulling the fuse in the old Vantages did, mechanically (without error codes) or electronically. Does something like this exist? I know for my Shelby there is a Valvetronic product that can do this for like $400. The only thing I'm seeing with the 4.0L Aston is a Capristo system which is $7k+... https://capristoexhaust.com/product/new-vantage-amr-valved-exhaust-carbon/

 

Also interested in this mod . . . I did not do the Cat Delete (Cali), I did go the Velocity AP Valvetronic path, I was concerned that it might be too much, but I love it. Agree, I hear the difference in Track mode and prefer not to hold my RPMs at the maximum at all times. KH

 

Hello guys,

The exhaust valves are a serious advancement from the older (pull fuse 22) days, where those valves are vacuum operated. With those valves there were a couple simple and easy always open workarounds.

Now, the EMS completely controls the opening of the valves, via the ECU, based on numerous operating conditions as well as various driver selected options such as sport modes. The flaps use a servo type motor rather than a vacuum and there is an infinitely variable opening % given numerous engine/trans situations.

I quit tuning as these new systems were coming onboard, but a tuner who knows what he is doing should be able to make modifications. Here are just some examples of what a tuner is going to see in some of the data tables of typical systems which so many performance car models now use.






There are a couple of companies out there, Renntech and Cete, that have developed an aftermarket intervention on the MB M177 platform that overrides the ECU controllable functions and keep the valves at 100% open. When you hear an exhaust using one of these devices, you realize there is no time in the factory program that has the valves opened 100% at idle ,startup or cold start. It's that much louder.

These devices are pretty complex. They intervene in the system as a node on the CAN-BUS.

Here is a pic of the Renntech



I couldn't begin to describe where this could intervene on the AM platform, and would take a willing engineer at one of these two companies. They should step over and make an AM option since these systems are the same.

Hope this helps.

 

Excellent information BWings! I absolutely do not understand why manufacturers will not give us 100% control over the exhaust valves (along with leaving settings in the place we left them after driving). These cars should have a menu for exhaust that lets you control settings that stick, and a quick change button INDEPENDANT of other drive mode functionalities. Thankfully the new Vantages at least let you keep dampers soft while changing to Sport/Track mode, as my 2014 went into rock hard road ride with a sport suspension if you wanted the sharper throttle response/features of Sport mode.

If Aston is using the same muffler/valves as MB does with the M177, then I would think the Renntech product you mention could work (and this is exactly what I'm looking for)...

As a related example, in 2019 I wanted a valve controller for my Shelby GT350R. While this car does at least have a stock toggle switch to open or close valves, it still does 2 very annoying things (I simply don't understand why manufacturers don't give us actual control of the valves???) (1) Regardless of mode/valve setting, the valves close in 6th gear unless you are at ~90mph then they open -- this means all highway driving gets closed valves unless you are speeding big time and takes away the glorious exhaust note and (2) I have a local track that has a DB limit that I get flagged if I don't short shift and let off the gas at the sound station, and regardless of the closed valve setting in the car, at WOT the valves will always open. At the time, AWE made a remote valve controller for the Focus RS, but not for the Shelby GT350's. https://awe-tuning.com/products/switchpath-exhaust-remote which I installed in my car and it worked perfect: Open for ALWAYS OPEN and closed for ALWAYS CLOSED, no more dumb *** factory overrides on the settings I chose. Unfortunately, I melted two of these units during extensive track use from super hot exhaust temps and gave up on them, but I'm confident for road use they work perfect and I still miss having that control, particularly to keep the valves open in 6th gear when for some dumbass reason Ford decided to close them even in Sport/Track mode or with the Exhaust Valve toggle to open...unless you are above 90mph. Idiots.

I see this controller which looks the same install/functionality as my Shelby, which is just plug in at the exhaust for $780: https://www.renntechmercedes.com/index.php/products/mb/amg-gt/gt-2018/gt-2018/evm-190-detail . Unfortunately, I suspect you'll need to pull the rear bumper to get access to the plugs on the Aston.

 

Well scratch that, I just got off the phone with an engineer at Renntech who says they have lots of Astons in and he promised me this https://www.renntechmercedes.com/index.php/products/mb/amg-gt/gt-2018/gt-2018/evm-190-detail controller will not work with Aston's valves. He said he's unaware of any ecu flash or product that will offer valve control in the Aston.

My local dealer is also of no help with this.

The AMG GT sounds fantastic in that Renntech video on idle, really sucks if there is no way to have the Aston in a true open valve all the time setting, especially since IMHO the secondary cat delete did not do all that much to overall sound level increase.

 

Hi Mike,

I've just listed my turbo back setup in the classified section, it may just be what you are looking for in terms of sound for your Vantage!

 

Appreciate the heads up, but international shipping won't be cheap and I'm very hesitant to put that kind of money into difficult to install primary pipes (CEL issues without a tune?) or another valved muffler I haven't heard in person to make sure it's a big enough difference to justify the cost and effort of removing the bumper to install. I literally don't want valves, just open flow! If it was possible to demo this stuff somehow, I'd be more open to it. GLWS!

 

https://quicksilverexhausts.store/co...xhaust-2018-on

More expensive than Velocity, but might be more on par with what you're looking for. You'd have to contact them to see if you can use their "key fob" to control the exhaust valves. In the videos, they show it being operated by the drive select button. However, this exhaust seems to have the most distinct difference between Sport and Sport+/Track.

 

most dealerships these days won't modify a car. as most features are associated with federal laws that mandated their existence in the first place. for the most part, shops that claim their mods are for racing are the only ones that will venture to do any significant mods.

some aftermarket companies that have done their homework do have products that comply, but even then, dealerships will tend to avoid installing them.

 

Agree on dealerships, and ime experience a lot of third party shops won’t modify exhaust stuff either which is partly why I am less interested in stuff that is not a diy for me. I did the cat deletes fine but not sure about pulling bumper for the muffler or snaking primary pipes in somehow.

 

Hi Mike,

Yeah, the EPA has really been getting stronger and stronger with emissions devices mods. They don't pursue you and me, but they get pretty heavy handed with businesses. Muffler shops can get fined taking CATS off cars even at the customer's request. Car dealers are getting hit too, taking trade ins with emissions devices defeated then reselling. EPA holds the dealer accountable so many are now doing deep inspections on trade in cars, especially CAT deletes. I know of a couple of guys with AMGs that did primary CAT deletes and dealers refused to accept the car on a trade in.

This was one big reason I gave up tuning. Even though I didn't run a business and never charged for a tune, it became more than I wanted to think about.

Best,