328 exhaust route | FerrariChat

328 exhaust route

Discussion in '308/328' started by SpiderBen, Jan 31, 2020.

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  1. SpiderBen

    SpiderBen Rookie

    Jan 31, 2020
    18
    Full Name:
    Benjamin VB
    Got a 328 with original exhaust and the CO2 on the right is too high. Do these gases come from the front or back cylinders? Because of the big difference in emissions I guess it’s not mixed.
     
  2. moysiuan

    moysiuan F1 Rookie
    Silver Subscribed

    Nov 1, 2005
    3,628
    Canada
    Where/how did you measure this?
     
  3. Tubi Sales

    Tubi Sales Karting

    Jul 5, 2019
    172
    PHX
    Do you have a US Spec 328 or Euro Spec 328?
    Depending on which spec you have the exhaust path differs.

    The US Spec both manifolds connect to a Y Pipe that goes to the Catalytic Converter.
    While the Euro Spec has an independent left and right side to the muffler.
     
  4. nerofer

    nerofer F1 World Champ

    Mar 26, 2011
    11,968
    FRANCE
    Yes, on the euro cars the front bank discharge into the (OEM) exhaust box on the right (=passenger's) side, and the rear bank on the left (=driver's) side; HOWEVER, the gases from both banks are mixed inside the (OEM) box. So the exhaust pipes, either on the left or on the right, do not expell gases from either the front, or rear, bank each: they each expell mixed gases from both front and rear banks. The inside design of the OEM (euro) exhaust box explains that pipes from one side discharge more gases than pipes from the other.
    Cut one exhaust box open and it becomes evident. I have already posted such a pic in the past.

    Rgds
     
  5. nerofer

    nerofer F1 World Champ

    Mar 26, 2011
    11,968
    FRANCE
    Re my above post, look at the picture enclosed in post #40 of this thread:

    https://www.ferrarichat.com/forum/threads/the-9000-exhaust.375076/page-2

    You have an OEM standard EURO exhaust box open.

    Rgds
     
  6. SpiderBen

    SpiderBen Rookie

    Jan 31, 2020
    18
    Full Name:
    Benjamin VB
    Many thanks for the replies. It’s a 1989 non kat euro, originally delivered to Germany.
    The emissions were measured during the annual vehicle inspection at idle. 4,69% on the right side (well above what is allowed) and around half that on the left. They even repeated the test. There was also more smoke/damp coming from the right.
    5 months ago there was a sudden loss of power. Took it to a local workshop, they replaced some parts of the injection system and later the distributor for the front bank, haven’t driven since then. Now, after the inspection they are going to replace the other distributor. By the way, I am a Dutch guy, living in Spain, previously named Treventotto here.
     
  7. mike32

    mike32 F1 Veteran

    May 13, 2016
    5,828
    Isle of man- uk
    Car has been sitting doing nothing so fuel will be a bit old. Try running the fuel down as far as possible and refill with 10 ltrs, put a full bottle of redex or other injector cleaner . Give it a good run to see if it helps your emissions.
     
  8. Iain

    Iain F1 Rookie

    Jan 21, 2005
    3,257
    UK
    Don't be distracted by the fact that you get a higher reading out of one side than the other at idle. That is just because at idle the thing will just put more gas out of one tail pipe than the other, its just the path of least resistance. As the revs rise the pressure in the system builds up & it evens up the flow, as Nerofer said, its all linked inside anyway. Use the side with the best /highest reading as your guide & just ignore the other one.

    Its possible that in the past the car has had an air leak in the injection system & someone has cranked the mixture screw up to compensate. Fix the air leak and suddenly the car is way too rich - this is what happened to my car before I bought it but I would go back to the shop & find out what they did when they "replaced some parts in the injection system" and ask them what else they did/adjusted.

    Otherwise, if it loses a bank (which will produce a sudden loss of power) then the usual culprits are either the coil to distributor ignition lead or the ignition amplifier module that sits on top of the coil.
     
  9. SpiderBen

    SpiderBen Rookie

    Jan 31, 2020
    18
    Full Name:
    Benjamin VB
    You are the best, guys! I will pass on the feedback to the workshop and look forward to burning fuel.
     
  10. thorn

    thorn F1 Rookie
    Silver Subscribed

    Aug 7, 2012
    3,322
    Tallahassee, FL
    Indeed. Be sure you have no vacuum leaks and proper ignition before you play with the mixture adjustments.
     

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