| Author |
Message |
Gordon Hollingsworth (Gordonh)
New member
Username: Gordonh
Post Number: 14
Registered: 5-2002
| | Posted on Sunday, September 21, 2003 - 12:29 pm: | |
Thanks guys! This has been very helpful. |
Peter Barbin (Sophia)
New member
Username: Sophia
Post Number: 31
Registered: 8-2003
| | Posted on Sunday, September 21, 2003 - 8:13 am: | |
Gordon, here's some reading of interest for you on this subject:
http://www.ferrarichat.com/discus/messages/256120/70384.html
http://www.ferrarichat.com/discus/messages/256120/2014.html
http://www.ferrarichat.com/discus/messages/256120/132921.html |
Terry Springer (Tspringer)
Member
Username: Tspringer
Post Number: 802
Registered: 4-2002
| | Posted on Thursday, September 18, 2003 - 2:14 pm: | |
The air injection nozzles themselves, if left in the head, offer a pretty good sized impediment to optimal airflow through the exhaust port. Overall... obviously a "quick and dirty" solution to the US emissions problem. Removing the nozzles has to help power as it will definitely remove a restriction and free up the exhaust flow.
I removed the nozzles using a gear wrench. Some of the ones on the front bank were a real pain. I also had lots of other stuff off the car.... typical Ferrari repair procedure really: step 1, disassemble car.
Having the proper plugs made to replace the nozzles is critical. If they do not have the correct machined "nub" on the end.... you will indeed get a wierd chirping sounds. Very annoying. Ask me how I know! |
Philip Airey (Pma1010)
Member
Username: Pma1010
Post Number: 438
Registered: 7-2002
| | Posted on Thursday, September 18, 2003 - 12:43 pm: | |
Gordon, Peter
I took mine off (at least partially). Here's what I did and my experience over the last season.
Front bank. Removed the pump, clips/clamps and hose through to the steel AI manifold adjacent to the #5 cylinder. Left the AI manifold inplace. Capped off the end of the manifold with a cap sourced from a plumbing supply house (it's a standard size). Rationale: access hard; removal hard; re-fitting hard. No visual imparement. No performance impact/miscellaneous other noises. Just seemed easiest.
Rear bank (better access). Pulled the pump et al. Dropped the exhaust header. Pulled the AI manifold (need crows foot wrenches). Pulled the stainless injectors. Had to replace one (Maranello/Ted Rutlands has them, about $70 each I think). Bought a set of brass caps from NAPA. Wound these on to the injector threads. Not quite the right thread but the brass is maleable enough that it'll conform. Tight. Replaced the now capped injectors back on the car. Re-connected the header (new gaskets). Put everything else in a box in the basement. All told, done about 6 months ago. No issues/noises/chirping or anything else. Just looks cleaner.
HTH |
Peter Barbin (Sophia)
New member
Username: Sophia
Post Number: 29
Registered: 8-2003
| | Posted on Thursday, September 18, 2003 - 12:29 pm: | |
Gordon, I'm in the process of researching and pulling the system off as well. I have some archive information I'll be able to post 9-19 in the eve...but Peter Rychel and Steve Magnusson have extensive information in the archives if you wish to search on your own.
More to post later! PeterB
The nozzles are stainless steel, they can warp under excessive heat...if air isn't blowing through them this could be a problem.
As for removing them, I'm going to pull the exhaust system off to the heads...If I have a warped nozzle, I can cut off the air tube from the exhaust port, then remove the threaded portion from the head. Soaking the nozzle area with "Mouse Milk" or "Liquid Wrench" is advisable, heat as well will help.
Plugs: Norwood Performance has them, but they lack a protrusion necessary to fill in the void in the head where the nozzle used to be... a 'chirping sound' could result. Thus, I'm going the route of SteveM & PeterR and getting plugs made with the void filling "tip."
Also check the archives, and start looking for a post by Terry Springer on 'chirping noises in the 308'...read on.
|
Gordon Hollingsworth (Gordonh)
New member
Username: Gordonh
Post Number: 13
Registered: 5-2002
| | Posted on Wednesday, September 17, 2003 - 7:19 pm: | |
I need advice concerning the air injection system on a carb 308. Is it really true that the air injection nozzles themselves will deteriorate from heat damage if the air pump is removed? The nozzles look like they would be difficult to remove. Are they made of brass? Is it better to crack them loose when the cylinder head is warm, or cold? Does anyone have a source for �plugs� to replace the nozzles, if removed? |