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Greg Rodgers (Joechristmas)
Member
Username: Joechristmas

Post Number: 644
Registered: 3-2001
Posted on Tuesday, January 28, 2003 - 11:41 am:   

I do too.
Jerry W. (Tork1966)
Member
Username: Tork1966

Post Number: 388
Registered: 7-2001
Posted on Tuesday, January 28, 2003 - 11:35 am:   

That is the only thing that I dislike about my '79 308 is that when I'm done with my drive, I stink like exhaust!
Mike Procopio (Pupz308)
Junior Member
Username: Pupz308

Post Number: 58
Registered: 10-2002
Posted on Monday, January 27, 2003 - 9:11 am:   

Burning is oil seems to be one issue I *don't* have, very fortunately--the car is farily frugal on its oil use...

Barring that, and any misfires, is it more likely the carbs, or the timing? Can you have bad timing that still provides no misfire, but just lousy combustion?


...thanks for the help...

'75 308 GT4 (Peter)
Intermediate Member
Username: Peter

Post Number: 2430
Registered: 12-2000
Posted on Sunday, January 26, 2003 - 12:01 am:   

Burning oil would contribute to higher HC levels. Maybe there's some weak rings in there...
Mike Procopio (Pupz308)
Junior Member
Username: Pupz308

Post Number: 56
Registered: 10-2002
Posted on Saturday, January 25, 2003 - 8:32 pm:   

Thanks, Barney, for the link, and to all for the help.

It's clear that 1200ppm HC emissions, without cats, means some major tuning problems somewhere along the lines.

This car has no misfiring problems--but it does feel sluggish. With that the case, what is most likely causing the excessive HC emissions?

Bad plugs, bad timing (single point), or bad carb tuning (running too rich?).


Thanks again for your help--

Mike
Barney Guzzo (Trinacria)
Junior Member
Username: Trinacria

Post Number: 88
Registered: 8-2002
Posted on Saturday, January 25, 2003 - 6:29 pm:   

Mike, look at this too:
http://www.ferrarichat.com/discus/messages/112/192809.html?1043445151
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas

Post Number: 635
Registered: 3-2001
Posted on Saturday, January 25, 2003 - 4:31 pm:   

Now if a car is to be set at 1% CO before the cat and is tested without cat at the tailpipe and it gets 1% CO is that ok/the same result?
JRV (Jrvall)
Member
Username: Jrvall

Post Number: 699
Registered: 11-2002
Posted on Saturday, January 25, 2003 - 3:39 pm:   

No ...these would be at the tailpipes -no cats- or before the cats.

The only testing after the cat is done by the inspectors for stickers.

Any other testing for tuning or to check condition have to be done pre cat.

For example...pre cat 300ppm....after cat considering cat is working efficiently...would be 100-150ppm. A good cat will only scrub 50%-60% of the incoming HC's and about 80%-90% of the incoming CO.

1200 is very poor running condition before or after.
Steve Magnusson (91tr)
Intermediate Member
Username: 91tr

Post Number: 1352
Registered: 1-2001
Posted on Saturday, January 25, 2003 - 3:38 pm:   

When you say "timing adjusted" do you mean "timing modified" or "timing reset to stock values and all the stock stuff is working"?
With regard to the "upstream-of-cat (or no cat) AND air-injection-disabled CO content", there should be a metal plaque in the engine bay with the numbers (IIRC -- which I probably don't -- it was something like 6% or 7% CO +/- 1%, but someone with a US '78 308 please state/confirm/deny). There are also "at the tailpipes if stock" HC/CO numbers too I think (which I believe are the HC/CO numbers JRV listed).
Mike Procopio (Pupz308)
Junior Member
Username: Pupz308

Post Number: 55
Registered: 10-2002
Posted on Saturday, January 25, 2003 - 3:29 pm:   

JRV,

Car's still in the shop (alternator)--I remember seeing those specs (they're also printed in the manual).

I don't recall if those are the emissions data with the cats installed, or without them... These are with the cats, right?

JRV (Jrvall)
Member
Username: Jrvall

Post Number: 698
Registered: 11-2002
Posted on Saturday, January 25, 2003 - 3:24 pm:   

The Factory specs should be on the Tune-Up Spec tag in your engine compartment.

1.5% +-.05% CO

300ppm HC's
Mike Procopio (Pupz308)
Junior Member
Username: Pupz308

Post Number: 54
Registered: 10-2002
Posted on Saturday, January 25, 2003 - 3:12 pm:   

Passed emissions where? And what where the specifications on HC emissions that you had to meet?

I'm not sure if the 308s have an EGR (Exhaust Gas Recirculation) system--I don't believe that it does...

Barney Guzzo (Trinacria)
Junior Member
Username: Trinacria

Post Number: 84
Registered: 8-2002
Posted on Saturday, January 25, 2003 - 2:54 pm:   

Does this car have an EGR system? Mine passed emissions with brand new stainlees exhaust and test pipes in place.
Mike Procopio (Pupz308)
Junior Member
Username: Pupz308

Post Number: 53
Registered: 10-2002
Posted on Saturday, January 25, 2003 - 2:46 pm:   

Hi guys,

My friend has a 1978 308 GTS, Carbed US model, really the identical car as mine except his car has the two catalytic converters removed.

The exhaust analysis is very concerning. With the cats on, the car's emissions were under control: <600ppm HC (hydrocarbon / unburned fuel), and reasonable CO%.

The cats came off, and the carbs / timing were also adjusted extensively.

The CO% is fine (1.5% to 3%, depending on idle/2000rpm respectively).

The hydrocarbon output was an INSANE:
It was greater than 1200ppm!


Even without the cats, should any carbed 308 be putting out unburned fuel like this? I noticed that my friend's car actually feels MORE sluggish after this service where the cats were removed and carbs/timing adjusted.

Is this normal? Anybody know of anybody's emissions specs on a carbed 308 without the cats?


Thanks,

--Mike




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