No Biturbo Thread? | Page 2 | FerrariChat

No Biturbo Thread?

Discussion in 'Maserati' started by johnireland, Aug 28, 2025.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. staatsof

    staatsof Nine Time F1 World Champ
    Silver Subscribed

    Mar 13, 2005
    96,249
    Fuggetaboutitland
    Full Name:
    Bob
    I know these cars like the back of my hands so is your car typically operated WO the air pump connected and only for smog tests? Answer via PM as you may not want that answer on a public forum.
     
  2. staatsof

    staatsof Nine Time F1 World Champ
    Silver Subscribed

    Mar 13, 2005
    96,249
    Fuggetaboutitland
    Full Name:
    Bob
    Well the air to water design takes advantage of the greater efficiency cooling with the water but there is no free lunch. So if you're pushing the engine hard say around a tight racetrack or flat out for many miles the entire system, heat exchangers and water heats up it with no down time for the water to cool down enough to provide the superior cooling effect it has on more intermittent loads. Typical driving will work very well with the air-to-water system thought you do get what feels like a secondary surge of torque once the very cool water in the radiator up front gets circulated through those Spearco units via the bilge pump which is turned on via the original pressure switch as boost rises. That's one reason why I changed that switch to a vacuum switch to so as to get the pump going earlier on the boost development curve.
     
    Ferraripilot likes this.
  3. Ferraripilot

    Ferraripilot F1 World Champ
    Owner Project Master

    May 10, 2006
    17,922
    Atlanta
    Full Name:
    John!

    Changing to a vacuum switch was a great idea!

    It's an interesting topic, and it's sort of all over the place in F1 with the future pointing to everyone being W2A as most have been. The last dozen years or so, Ferrari have been running water to air, likely because water to air can be so compact. Mercedes also ran a W2A cooler, but Mercedes customer teams chose to run A2A at first. Then in 2022 the regulations allowed 3d printed W2A coolers, so Ferrari, Mercedes, and Alpine all ran W2A, except McLaren who ran A2A. Red Bull have always run A2A with Honda. W2A is heavier, but is overall less volume to install as the radiator doesn't have to be nearly as large as A2A units to be efficient.
     
    staatsof likes this.
  4. peterp

    peterp F1 Veteran

    Aug 31, 2002
    6,699
    NJ
    Full Name:
    Peter
    I've been too scared by the reliability reputation to ever think about buying a Bi-Turbo, but I've always admired them. I love sleeper cars like this that are very subtle in design, while being special and rare, with great performance. A manual seems like a perfect car for to enjoy daily. Are those seats and interior as comfortable as they appear?
     
  5. staatsof

    staatsof Nine Time F1 World Champ
    Silver Subscribed

    Mar 13, 2005
    96,249
    Fuggetaboutitland
    Full Name:
    Bob
    Yes. They are by far the most comfortable seats I've ever traveled in. When you get out of the car after a long drive nothing hurts. They spoil you for all other cars. The downside is that they are conducive to sporty driving. You have to modify these cars and then they are quite reliable but setting valve clearances is a SOB, fraught with potential disasters. You also have to do all the yourselves as there's almost no one who knows how to work on them or have the patience to do the job the way it should be done.

    I've helped to run one of the longest running and earliest website BiturboZentrum and I've seen so many people who buy a nice looking example then end in disappointment, disgust and disaster.
    I am unable to work on mine for a couple of years now and so I'm contemplating teaching my Jag mechanic how to replace the water pump by being there while he does the work. I'm not sure how this will work out but he works on a lot of different stuff. He's a racer, race mechanic and does very well on modern cars as well. You really do need to modify the suspension if you have the liquid inter-cooled car or you'll kill yourself.

    This guy knows how to work on them but he's retired. The shop has been taken over by someone else https://www.daveburnhamcitroen.com/
    He turned an 84 or 85 coupe into a race car.
     
    peterp likes this.
  6. peterp

    peterp F1 Veteran

    Aug 31, 2002
    6,699
    NJ
    Full Name:
    Peter
    Thanks for the detailed info. I think I'd really enjoy owning one, but I'm probably past the point in life where I want to work to maintain a car. Some less reliable older cars can be made better with aftermarket improvements and known remedies, but some remain difficult to fix. Sounds like Bi-Turbos are (like vintage Lotuses) in the latter category.

    My son just got a used Giulia Ti Sport AWD and it's had some stupid issues (plastic radiator & intercooler coolant bleeders, plastic coolant lines), but hopefully will be reliable with the known ares fixed. It's an amazing car otherwise.
     
  7. ArgentoQV

    ArgentoQV Rookie

    Mar 8, 2021
    19
    San Francisco Bay Area
    Full Name:
    Chris
    I had an 84 Quattroporte as well as 3 V6 Alfas. The Biturbo is no more or less reliable than any of them. They are not worth restoring but the survivor cars are definitely worth seeing out and saving. The interiors are simply amazing, even on the older versions.

    Image Unavailable, Please Login Image Unavailable, Please Login
     
    ProCoach, MrMark and peterp like this.
  8. ProCoach

    ProCoach F1 Veteran
    Owner

    Sep 15, 2004
    5,467
    VIR Raceway
    Full Name:
    Peter Krause
    My shop in North Carolina worked on a dozen-plus Biturbos, late Eighties through mid-Nineties. I could get the blow-through cars to work well enough, but the IAW-Marelli FI was MUCH better, obviously. By then, the cars were good, just got hammered with the reputation of the carb cars.
     
    peterp and Ferraripilot like this.
  9. TheMayor

    TheMayor Ten Time F1 World Champ
    Rossa Subscribed

    Feb 11, 2008
    107,102
    Vegas baby
    Yep. Working on the water / air was just a PITA to do anything. Just added labor to the job. I'm really not sure how much it added in HP given so many carbs were out of tune.
     
  10. TheMayor

    TheMayor Ten Time F1 World Champ
    Rossa Subscribed

    Feb 11, 2008
    107,102
    Vegas baby
    #35 TheMayor, Sep 22, 2025 at 11:50 AM
    Last edited: Sep 22, 2025 at 12:02 PM
    No, the Bi-turbo was less reliable by far. It had some inherent flaws in the engineering. And quality control was worse. IMO, its because Qvale (the importer) said he would do the warranty work to get a cheaper price from DeTomaso. Well, the factory didn't care what it sent to the USA after that as long as it got them on the boat.

    Like there's this little temperature sensor literally plastic tied to the radiator hose which was CLEARLY an afterthought / shade tree engineering. It turned on the fans with the temp got to high on the top of the radiator. Most mechanics not trained didn't know to put it back or at the right place-- and the cars overheated in traffic.

    And yes, the Qporte interiors are amazing and extremely comfortable. The Qporte engine was bullet proof. But the fuel mileage --- Don't ask!

    Someone sued Maserati USA for the Window Sticker. It said "suede" interior but "suede" is technically leather. In fact it was Alcantara, which is plastic. He won. Today Alcantara is considered to be better than suede. Back then, it seemed like lying about the materials used.

    Lots of weird stuff happened with US cars.
     
    Ferraripilot likes this.
  11. ArgentoQV

    ArgentoQV Rookie

    Mar 8, 2021
    19
    San Francisco Bay Area
    Full Name:
    Chris
    I should have said *my* Biturbo is no more or less reliable than my QPIII or my Alfas, or even my 308 (which has actually been towed more times). I see good looking Biturbos (Biturbi) on BAT but a lot of potential bidders hold back because of the reputation.

    @johnireland did you ever do the trade for the Alfetta GT?
     
  12. staatsof

    staatsof Nine Time F1 World Champ
    Silver Subscribed

    Mar 13, 2005
    96,249
    Fuggetaboutitland
    Full Name:
    Bob
    Did you ever get a tour of the Biturbo factory in the 80's? Talk about a horror show. The parking lot was full of abandoned, misassembled cars. Once I saw that it explained a lot. I became well acquainted with the technical guys in Baltimore and and Los Angeles, I think his name was Greg Long. He helped me with a lot of the mods/repairs and got me to the right person @ Centerforce Clutches. That was the best clutch I ever had on that car. Both offices were very good to me.
     
    TheMayor and peterp like this.
  13. TheMayor

    TheMayor Ten Time F1 World Champ
    Rossa Subscribed

    Feb 11, 2008
    107,102
    Vegas baby
    Yes we used Centerforce also. MIE was really good in giving feedback to independent service centers about what they were seeing.
     

Share This Page