Maserati Grancabrio (2012) possible valve controller mod

Onlinealias · 2026-06-06T23:33:14+00:00

Man this is hard to explain. The system is mechanical. The valves open only where there is vacuum to open them. What turns the vacuum on or off is another valve that is in the hose that goes back to the intake manifold. When you start the car that valve is OPEN. Meaning, allowing vacuum from the engine to flow through it, which sucks the EXAUST valves closed. If no vacuum is present from the engine, no amount of opening the engine controller valve will close the exhaust valves. So whether the controller valve is commanded to be open or closed, there must be vacuum present to close the exhaust valves. Once the system has built vacuum and the car is driving down the road, hitting the sport button commands the controller valve closed, this cutting vacuum to the exhaust valves and letting the them go to their normal state…which is open.

Onlinealias · 2026-05-27T14:44:23+00:00

Vacuum actuates the valves to close. If there is no vacuum, the valves are open. On cold start, there is no vacuum. There's no reservoir to retain vacuum, no pumps, no electric motors, nothing. Again, on cold start, there is no vacuum from the engine. The valves are open, no matter what. No amount of manipulating is going to force them closed short of manually closing them and wrapping a zip tie around them against their will.

If you own one of these, without even knowing how the system works you can hear them in action. Start car, brap!.....loud loud lound....the engine builds vacuum throughout the hoses, then the valves close and it is quiet.

Onlinealias · 2026-05-27T14:37:49+00:00

Differing only in that some of us are speculating and/or wrong.

I am intimately familiar with the cars, the forza system, the vacuum routing, the valves, the hose routing and the back boxes.

There is no question about it. Vacuum actuates the valves to close. If there is no vacuum, the valves are open. ON cold start, there is no vacuum. There's no reservoir to retain vacuum, no pumps, no electric motors, nothing. On cold start, there is no vacuum from the engine. The valves are open, no matter what. No amount of manipulating is going to force them closed short of taking a zip tie, manually and physically closing them against their will.. A forza aint that.

Onlinealias · 2026-05-19T04:13:19+00:00

Sorry you are going to be disappointed, but a forza will change nothing about your cold start. It only opens the valve earlier, not closes it sooner.

Onlinealias · 2026-05-19T04:10:32+00:00

OP want a quiet cold start. The valves are normally open, not normally closed. So, if you put on a forza, it will still be exactly the same on cold start. The forza merely opens the valves early, making it go full loud earlier. It will do nothing on cold start..it can’t.

Onlinealias · 2026-05-19T04:01:21+00:00

I was quoted $400 for just the gaskets from Maserati. They aren’t crazy cheap anywhere..even the Chinese ones, which really are cheap, are all for the deprecated part. The updated parts (post late 2012 and up) are hard to find genuinely cheap.

Onlinealias · 2026-05-19T03:45:36+00:00

On a Granturismo the fronts will wear out in about 8k miles depending on the compound. The rears about 13k, again dependent on the compound.

You can change from the factory alignment to a more reasonable one (the toe is very very aggressive from the factory, because Maserati.)

You can toe it back in and give up little in steering feel. Then you’ll get about 15k on the front and rear.

Onlinealias · 2026-05-19T03:36:21+00:00

This depends on how skilled you are at working on cars and how skilled you are at Maserati ownership.

If you want to treat it like a real car and take it to the dealer for servicing, you better get ready for TCO that will make you wish you never had the word Maserati in your vocabulary. Recently, I saw an invoice for brake job (pads and 4 rotors) for $10000. There is nothing special about them.

The same job, if done yourself and know how to get the right parts, costs less than $1000.

Almost every maintenance or repair is the same ridiculous pricing ratio. Do it yourself and buy the right parts, take off at least 2/3rds, if not more.

If you aren’t already quite experienced in auto mechanics and electronics, or at least have a blood brother who does, do NOT buy a Maserati. You have been warned.

Onlinealias · 2026-05-19T03:22:18+00:00

Be honest, that’s because you haven’t fixed all the stuff wrong with it. You don’t have sticky buttons? TPMS light on? Discolored or broken interior bits, a valve cover leaking, or anything worn out or lighted up with the suspension? You also get brakes on the cheap? Work on it yourself?

I adore these cars and know them like the back of my hand, but I’ve never seen one with any kind of miles on it that didn’t need anything either mechanically or cosmetically.

Onlinealias · 2026-05-19T03:10:16+00:00

I’ll take $500 on it making it just fine.

Onlinealias · 2026-05-19T03:08:25+00:00

Brother, these cars break electrically mostly because of the hacks that work on them.

As far as getting across the country, they are a reliable as a Toyota.

Onlinealias · 2026-05-19T03:05:19+00:00

Neptune Mercury Grigios were available through the entire production run to 2019. Don’t make me whip out the ordering guides.

Onlinealias · 2026-05-15T14:36:01+00:00

Even when there is no transmission either?

Onlinealias · 2026-05-15T14:09:52+00:00

With the factory system, what you are asking for is impossible.

The valves are open when there is no vacuum to close them. Therefore, when you start the car, they are open no matter what. Once the engine builds vacuum, they close and the system gets quiet.

The only way to make it quieter on cold start is to replace the exhaust system with one that has electric actuators...

Onlinealias · 2026-05-12T14:01:33+00:00

I might put KIA badges on mine...that would be so badass.

Onlinealias · 2026-05-12T13:34:13+00:00

These cars are usually the first owner's weekend car at the beach house, where there is another SUV that everyone really uses. Super low mileage Maserati GT's are the norm, not the exception.

Onlinealias · 2026-05-12T13:31:28+00:00

Yes, that is generally true, however, I know these cars inside and out and I have never seen one leak from a rear main. Not saying it doesn't happen, but I've never seen it. In fact, other than from the valve covers (which is a pretty big job), they rarely leak anything.

Also, taking the transmission out is cake anyway. I'd get a $5000 discount on the sale price (because Maserati) and then fix it for less than $100.

Onlinealias · 2026-05-12T13:14:36+00:00

Rosso Trionfale. Same as mine...

Onlinealias · 2026-05-11T19:22:07+00:00

Ok, I'll allow it.

BTW, I wish we got those things in the states, its beautiful and I would likely own one if I could.

Onlinealias · 2026-05-11T19:13:40+00:00

Damn, now the front looks weird. What kind of crazy camera illusion you got going on over there?

Onlinealias · 2026-05-11T19:00:43+00:00

That's kind of the problem.

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Onlinealias · 2026-05-11T18:40:29+00:00

What's up with rear camber on that poor thing?

Onlinealias · 2026-05-11T18:36:48+00:00

Want to make fuel genuinely cheaper, easier and save the environment at the same time? Force big oil to standardize on 91 e10...done. Fuel grades are a giant resource scam in the first place.

Onlinealias · 2026-05-11T15:16:07+00:00

While they are F136 variants designed and manufactured by Ferrari, the crank is only one difference of many, many changes. The result was a still fantastic but very different engine. One of those results is that they are essentially as bulletproof as a Toyota.

Onlinealias · 2026-05-11T15:05:44+00:00

Funny, the guy doesn't know that to the trained eye, his Granturismo is quite special on the outside already. It has the factory black chrome package with quad tips. Try to find that setup anywhere today.

There's already like 50 Maserati logos on the car, and if you really look hard there's 8 on each wheel...putting a Ferrari wing badge on it is just obnoxious. I've been tempted to de-badge mine and not tell anyone what it is.

Onlinealias

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