Like many 308 owners who don’t like the idea of having the engine rev madly at warm up I want to remove the unnecessary valve Just wanted to ask if anyone has removed the 3 way connection on the pipes and bypassed it with a single piece of hose? It would have to be bent slightly into an “S” shape to fit bit seems relatively easy to do. The other pipe on the lower end in the photo would still have to be plugged i guess unless there’s a bypass pipe can be made for that too? Also wanted to ask if people have removed the solenoid that activates this valve as this would then be useless as I couldn’t find any threads on that, seems to make sense? Image Unavailable, Please Login Sent from my iPhone using FerrariChat
If you want to get rid of the cold start high RPM because you don't like the sound of the immediate 2k (or whatever), that's fine but if you are worried about increased engine wear, forget about it. The critical thing on an engine starting is that oil pressure come up as quickly as possible. Obviously, oil pressure comes up quicker if the RPM is higher. What this means in reality is that the number of revolutions that the engine has to rotate from the instant it starts until pressure builds to a proper level is about the same regardless of the initial idle RPM.
I would just leave it in place and reroute the vacuum line. Cars with all the OE parts are worth more at resale and that gets to be more important with age.
I dont think the motor revving at whatever RPMS at start up, can be considered " mad " or to high. Ferrari has engineered / designed the car to work like it does on cold start up. LIke 996 has mentioned, not to worry about engine wear , and I agree with that. My car has 103 k miles, my fast idle works perfectly, I am of the more "anal " when it comes to all the systems of my car working correctly , other than the AC, which is now rebuilt and working correctly. The fast idle, or cold start RPMs, gives the motor a chance to heat up and to get the 9.5 quarts of oil circulating as it should. I would leave it as it should be, other than replace the unit thats causing the buzzing sound. Thank you
This system is only on 80-83 US 308's. If you are not driving one of those you have not experienced what happens. It was installed to pass US emissions only until the new fuel injection system was available in 1984.
I was under the impression that whichever the system , fast idle , whether on fuel injected or carbed 3x8s was just that particular model years warm up, or cold start system revs , my 89 revs at about 1100 RPMs on cold start up. I usually let the car idle at that rate until it drops, or after a couple of minutes until I drive off. Im not going against you, just asking, I know your just about the most experienced here with Ferrari. My car will not pass smog when tested unless its run on the dyno, it will not pass on static , maybe my car has a problem that I am not aware of. Thank you
1100 RPM would be acceptable for a warm up but 2500-3000 is crazy, and as stated only on US models for emissions so not really necessary as no other car has them Sent from my iPhone using FerrariChat
80-83 is different. Runs about 3000 rpm for about 2 minutes at cold start. The parts in the picture are on no other model.
Connect the hose from the valve directly to the intake manifold port. Then it will work like all the rest.
I agree that any rerouting or removal would be reversible if required in the future, this procedure shouldn’t be difficult to do Sent from my iPhone using FerrariChat
Brian, Can you describe that better or 'paint a picture' so a dummy like me can follow, and what would that 'reroute' change in operation of the car? Posted this before I read your later post but am still lost.
The valve is held closed by vacuum so you need a constant vacuum source. There is one hose from the plenum chamber vacuum port to an electrovalve. There is another hose from the elctrovalve to the additional air valve. Make the hose at the additional air valve go directly the the vacuum port on the plenum.
Decades ago I replaced the above assembly in the picture with the simple tube below. The replacement tube was a correct OEM part, likely for non-USA models of the same era. Image Unavailable, Please Login
On my previous car I put an aluminum plug inside the hose. I put a hole in the center to flow a little air. That hole was maybe 3/16"? It reduced the 2k+ rpm to a much more reasonable 1200-ish RPM while cold, perfect for a cold start and much more normal feeling.
I don’t suppose you have a record of the part number that you bought for it? It’s exactly what I’m looking for Sent from my iPhone using FerrariChat
No, but as I recall at the time I pulled up the factory parts guides for the USA-spec version, and then the Non-USA-spec version, and compared the two. You can then identify the parts of interest between them, and use the guide documentation to get the part numbers.
A lot of manufacturers did this to get the catastrophic converters heated up into their "operating temperature window" more quickly. As such, I believe "mechanical sympathy" took something of a back seat. I would not assume it's a good thing or okay just because they did it.
^ '... catastrophic converters ...' I know it's an 'Auto-Correct' error, But it's quite Apropos at times, too.