Maserati Ghibli II V6 2L - Simulator data

[alpa]

Seems like the article has about the same as me overall opinion about the open road behaviour of these cars: it's OK, not more.

Funny excerpts:
Race derived braking and track developped chassis (Brakes are not good, to be polite, and the chassis is the same as on the GT. My GT went to the track, you can see its pictures in my thread: totally destroyed. Perhaps someone mentioned the Open Cup chassis and they forgot to write down "open" ?).

(The drawing of the suspension architecture shows a wrong front antirol bar. How do they do ?)

The Cup's extra gear ratio (Do I undestand correctly that Cup had a 7 gear transmission ?)

It seems hard to believe that the same bunch of engineers responsible for the misguided QP (I guess QP4) also conceived, developped and eventually signed off the chassis of this car (I'd be currious to know differences between both except for the front struts, an improved floor reinforcement under the firewall and a longer QP body. I'm pretty sure that even front bearing hubs are the same, despite the different struts).

 

[Nayf]

Seems like the article has about the same as me overall opinion about the open road behaviour of these cars: it's OK, not more.

Funny excerpts:
Race derived braking and track developped chassis (Brakes are not good, to be polite, and the chassis is the same as on the GT. My GT went to the track, you can see its pictures in my thread: totally destroyed. Perhaps someone mentioned the Open Cup chassis and they forgot to write down "open" ?).

(The drawing of the suspension architecture shows a wrong front antirol bar. How do they do ?)

The Cup's extra gear ratio (Do I undestand correctly that Cup had a 7 gear transmission ?)

It seems hard to believe that the same bunch of engineers responsible for the misguided QP (I guess QP4) also conceived, developped and eventually signed off the chassis of this car (I'd be currious to know differences between both except for the front struts and a longer QP body. I'm pretty sure that even front bearing hubs are the same, despite the different struts).

Funny how we can interpret the article in different ways - this is a very positive review, I feel. The negatives are largely the brakes and the interior. You seem to have a very negative view about the Cup in general; as someone who has driven the GT and Cup back to back regularly, I cannot understand how you’re unable to tell the difference in steering feel, grip and performance.

 

[alpa]

The quality of my 97 GT assembly.
These are lateral bars that are supposed to strenghten the front of the body under the floor, where the engine frame connects to the main body.
Once the later and the factory putty are removed we can see that the bars were not fully welded to the floor. The factory weld points are visible on the white factory painting (the car is blue).
I'm absolutely sure this part was never repaired. Everything looks stock.
All the traces of welds are by me. There was a hole in the floor on one side and I heavily modified these parts of the body so the floor is welded to some additional sheets of steel.
I should have removed putty before starting any repair. But the car was lifted on these points so I didn't have access. Now I have to weld and paint again.

 

[alpa]

Funny how we can interpret the article in different ways - this is a very positive review, I feel. The negatives are largely the brakes and the interior. You seem to have a very negative view about the Cup in general; as someone who has driven the GT and Cup back to back regularly, I cannot understand how you’re unable to tell the difference in steering feel, grip and performance.

The first article says that the engine "struggles to put its ferocius 330hp down neatly off the line", the gearbox stick is "neither as accurate nor as light as we'd have liked", and that handling is not so good on the route. The second says the M3 does not have soul, which is not a technical consideration. 0 to 60 timings are quite useless notions for road cars, they give an idea about the performance, nothing more. The Cup steering is precise and feels good, but it's the same for all 5 bolt biturbos, including 430, 222 and so on.

I haven't driven the Cup but I can't see how it can be radically different from GTs given the fact they were assembled from exactly the same parts (except Cup springs). I've driven GT, Primatist (which is a GT, I spent 50 hours repairing the car and mapping the engine), 2.0 and 2.8 non abs ghibli. And I owned a qp4 v8 otto. I do all the mecanic work myself, restore/modify biturbo chassis (which are all quite the same) and engines (18 and 24v), havily modify the distributor engine computer firmwares, own a quite large stock of parts of all these models.
And a friend runs a maserati workshop in France, we often talk about disasters he sees and repairs, most frequently ghibli and qp4. When you see the damages these cars have when driven (from time to time) on the route you can easily imagine how bad they would be after a track session.

My opinion is negative about that kind of articles that people use as a reference. If authors were NOT talking about technical aspects they don't understand these articles would be much better.
To me a Cup is just a better tunned GT. And I've never found any ghibli as performant as people pretend they are. They are heavy (non abs ghibli were much lighter), suspensions are soft and imprecise, they don't brake well and the engines are slow to react. But all that is not due to fundamental problems, except for the soft bodies made of chewing-gum black steel. It's due to many small imperfections and weaknesses that once put together give not "finished" cars.
The engine mapping on all biturbo is a disaster. It's better on static ignition versions. Install a wide band lambda kit and you'll see how lean are transients. This is why turbos are so slow to spool up. The mapping is very approximative.

I love these cars, that's why I'm using them as daily drivers. But they need heavy improvements (including front seats on 2 door models) to be really safe and performant if driven as sport cars. Engines and transmissions are ok/good/excellent, depending on the models, even though some parts are of poor quality.

 

[Nayf]

I haven't driven the Cup

Ok.

 

[stormrider123]

 

[alpa]

Looks much more realistic: both engine response and suspension. For the body roll a x1.5-2 speed playback is handy.
Would be interesting to try on a slower track with tight left-right turn passages. And a run with accelerations starting from 3000rpm.

 

[stormrider123]

Looks much more realistic: both engine response and suspension. For the body roll a x1.5-2 speed playback is handy.
Would be interesting to try on a slower track with tight left-right turn passages. And a run with accelerations starting from 3000rpm.

Thanks Alexis, I like the idea. Gonna try that tonight at Magione, I think it fits your description of slower track with tight left-right turns.

I'm still struggling a bit with the springs, I haven't been able to calculate their rates yet and the anti roll bar's complex shape is driving me crazy. I decided to try a different approach, going directly into solidworks and modeling variable pitch springs and then into a FEA simulation platform to work out the spring rates.

My calculations were giving me some big variability. Very low front arb rates, and very stiff front spring rates (wheel rates). The rear spring is easier in that it has 9 coils, but 3 of them are dead and the natural frequency makes sense.

Yesterday while searching for a supposed Ghibli's workshop manual, I discovered that Maserati never made one, but instead, refered to the Quattroporte's. I tried searching around, but could not find a pdf. Does anybody has one to share or at least to scan a few selected pages?

Does anyone of you lucky Ghibli owners play Assetto Corsa?

Cheers

 

[alpa]

The front antirol is not stiff. I don't think Cup had a stiffer one. To me it does not make sense to have stiff front springs and soft antiroll on sport cars. It should be the opposite. But they did this way.

The rear antirol is soft on all biturbo (means racing, 222 4v and all ghibli/qp4).
I have sets of not Cup springs off the struts, I could do measures and then you'd extend to Cup springs. Not sure this could help.

Ghibli workshop man exists. I don't have it but a friend runs a Maserati garage and has all mans. Tell me what you want to know, he could send photos of few pages. He won't take 100 pictures.
Quattroporte 4 front struts are specific to QP4. You can't use them for ghibli that had same struts as all previous 5 bolt biturbo.
Rear shocks are the same on all biturbo including 4 bolt ones. Of course they are supposed to have different dumping numbers, but given the precision of all the rest I'd say they are the same. I drove my 430 with qp4 v8 rear shocks and springs and it was just right, while the qp4 v8 is 300kg heavier.

 

[stormrider123]

The front antirol is not stiff. I don't think Cup had a stiffer one. To me it does not make sense to have stiff front springs and soft antiroll on sport cars. It should be the opposite. But they did this way.

The rear antirol is soft on all biturbo (means racing, 222 4v and all ghibli/qp4).
I have sets of not Cup springs off the struts, I could do measures and then you'd extend to Cup springs. Not sure this could help.

Ghibli workshop man exists. I don't have it but a friend runs a Maserati garage and has all mans. Tell me what you want to know, he could send photos of few pages. He won't take 100 pictures.
Quattroporte 4 front struts are specific to QP4. You can't use them for ghibli that had same struts as all previous 5 bolt biturbo.
Rear shocks are the same on all biturbo including 4 bolt ones. Of course they are supposed to have different dumping numbers, but given the precision of all the rest I'd say they are the same. I drove my 430 with qp4 v8 rear shocks and springs and it was just right, while the qp4 v8 is 300kg heavier.

Thanks Alexis, the measurements of the cup springs would definitely help. Were those the same as the "Kit Sportivo"?

For the workshop manual, specific the pages that I'm looking for are the Ghibli equivalents pages below:
Edit: Do you have the anti roll bars off the car?

 

[stormrider123]

2nd video with shorter bumpstops.

I think I finally found the right spring rates. Now I need to improve the suspension travel range and anti roll bar rates.

Cheers

 

[Ewan]

Ok.

Well said!

I‘m now just waiting to be told that the MC Victory drives the same as a 4200 coupe, by someone that’s never driven one!

 

[Ewan]

Stormrider - loving your work. Well done. I had no idea such research went into making these games. Impressive.

 

[stormrider123]

Stormrider - loving your work. Well done. I had no idea such research went into making these games. Impressive.

Thanks Ewan, it's incredible how much these mass market simulators have improved over time. It reached a point where you can, most of the time, input real data and expect it to behave within a reasonable margin of error.

 

[alpa]

Well said!

I‘m now just waiting to be told that the MC Victory drives the same as a 4200 coupe, by someone that’s never driven one!

So you are basically saying that it's impossible to analyze phenomena or objects if you don't personnally take part of them ? Engineers can't analyze structures if they are not on the bridge when it breaks, transmission quality can't be qualified if you don't call from the exact place with your phone, and so on ?

There are facts. In case of the Cup the facts are that it's exactly the same body (made of the same chewing-gum steel sheets as the first biturbo), same steering, same suspension as other GTs. The only difference are springs, engine tune up and possibly antiroll bars. So how can steering be much more efficient ?

Can a Cup have a better balanced suspension : yes. Especially because biturbo suspension adjustment has always been very approximative. Faster spooling turbos : yes, even a better engine mapping could do that. Be a radically different car on the road : no. In that case I'd suspect the Cup body was in a much better condition because many ghibli are cracked on the front.

And I did not say a Cup does not "drive better". I said it's still the a GT with all its weaknesses.

 

[alpa]

2nd video with shorter bumpstops.

I think I finally found the right spring rates. Now I need to improve the suspension travel range and anti roll bar rates.

Cheers

Looks realistic.
I've just realized: it's a 2.8 engine model, right ? Does Cup rev up to 7000rpm ? All other 2.8 were rev limited at 6300.

Ps: the friend does not have suspension data for ghibli. Only ghibli engine and electric stuff manuals.

Btw, do you know the thinkness of the Cup antiroll bars ?

 

[stormrider123]

Looks realistic.
I've just realized: it's a 2.8 engine model, right ? Does Cup rev up to 7000rpm ? All other 2.8 were rev limited at 6300.

Ps: the friend does not have suspension data for ghibli. Only ghibli engine and electric stuff manuals.

Btw, do you know the thinkness of the Cup antiroll bars ?

Thanks Alexis. I knew that the 2.8 engine had a lower rev limit, but I didn't know exactly how. I'm gonna fix that ASAP. It was currently at 6500 with perhaps a visual error on the 3d dash.

For the Arb rates, the information I have is that the stock Ghiblis had 14mm front, 13mm rear, while the Cups had 18mm front 14mm rear. Is this correct?

 

[alpa]

On my GT 2.0 it's 17.3mm front 13.5mm rear. With painting of course.
For the rev limiter on 2.8 I guess the soft one is at 6300, the hard cut 6500. I will check if I have the tunerpro config for these eproms.

 

[Ewan]

Having owned a 2.0 lt. Ghibli ABS, a 2.8 lt. Ghibli GT and two other 2.0 lt. Ghibli Cup cars, I am happy to confirm that they all three models had different performance, different handling and generally different characteristics.
Just as my QP4 Otto drives differently to my three QP4 Evo V8s.
I suppose that's part of the fun of owning cars that are partly hand built, and to varying degrees of quality.
The one thing we know for sure is that no two Maserati's from that era are identical, no matter what the generic spec sheets says.

 

[alpa]

What's the Cup final drive ratio ? On my GT there is a huge stamp 3.45. I still need to check if it's true