Lancia Motor Club

Model Technical and Interest => Fulvia => Topic started by: Caracad on 10 October, 2015, 07:16:31 PM



Title: S3 Air Filter Question.
Post by: Caracad on 10 October, 2015, 07:16:31 PM
As a new Fulvia owner I am still learning so bare with me.
The air filter on my car has 3 parts to it. Outer cover and casing fixed to carbs and also an internal "baffle" type of thing.
Can't work out what this is for but it must restrict air flow. Actually I can't work out the engine gets any air at all.
Anyone know what this does and if I can just remove it?


Title: Re: S3 Air Filter Question.
Post by: fay66 on 10 October, 2015, 09:55:44 PM
As a new Fulvia owner I am still learning so bare with me.
The air filter on my car has 3 parts to it. Outer cover and casing fixed to carbs and also an internal "baffle" type of thing.
Can't work out what this is for but it must restrict air flow. Actually I can't work out the engine gets any air at all.
Anyone know what this does and if I can just remove it?

Do not dispense with the baffle as it's an essential part of the airflow to the carburettors,
Don't understand what you mean by you "can't work out the engine gets any air at all" ???
there should also be two rubber spacers that stop the baffle rattling.

Brian
8227 8)


Title: Re: S3 Air Filter Question.
Post by: lancialulu on 11 October, 2015, 06:53:16 AM
Just to clarify the rubber spacers (little tubes c15mm x20mm) sit between the outer case and the baffle on the m6 studs. As Brian says this not only is designed to produce good airflow but also acts as a flame barrier should poor tuning make the carbs spit back. Not intuitive at all but that's Lancia!


Title: Re: S3 Air Filter Question.
Post by: Caracad on 11 October, 2015, 09:00:00 AM
Thanks for replies guys. As you say, Lancia powertrain engineers had good reason to design it that way.
I suppose I was thinking it was possibly there to reduce induction noise on the later cars, in which case I could do without it.

My car does feel a little strangled at higher revs. Not driven it much yet but that was my impression especially given the power on these small engines is at the top end of the rev range.

Anyway I will check the timing and put some decent fuel in the tank and not mess with the airbox.

I have to say working on this car is a joy. These little cars are beautifully designed and made. I am completely smitten with the thing.



Title: Re: S3 Air Filter Question.
Post by: Richard Fridd on 11 October, 2015, 09:25:21 AM
A new timing chain can perk things up


Title: Re: S3 Air Filter Question.
Post by: dhla40 on 11 October, 2015, 02:07:30 PM
If your car is a later model it may have 115 main jets which are a bit marginal with todays dodgy fuel. I have changed my air correctors from 180 to 150 to compensate but next time the carbs are off will put 120 main jets in to be on the safe side.

Sean


Title: Re: S3 Air Filter Question.
Post by: davidwheeler on 16 October, 2015, 01:54:23 PM
Yes, bigger jets are needed and also high octane fuel is essential.  They just don't go on 94 octane!    I have increased the intermediate jets to improve low speed pickup but need to go another side up really.(But that's on a series 2)


Title: Re: S3 Air Filter Question.
Post by: Caracad on 17 October, 2015, 08:58:27 AM
Thanks for the replies.
Interesting about carb jets. Last car I had with carbs was an Alfa which if anything was over fuelled. It didn't need choke when cold.
Do I need to remove the Solex carbs to fit new jets. I'm sure with Webers removing the tops gave access to the jets.


Title: Re: S3 Air Filter Question.
Post by: Neil on 17 October, 2015, 10:00:05 AM
On Solex carbs, you need to remove them as the jets are accessed from the underside to my knowledge, unlike Dellortos DHLB35 (& Webers) are accessible from the top.


Title: Re: S3 Air Filter Question.
Post by: lancialulu on 17 October, 2015, 10:04:49 AM
The idle jet is accessible from the top?? Only the main needs removal which is a bit of a fag and on 42 up this can introduce air leaks at the manifold to compound the job.

Get a setting and live with it is my advice.

I had a weird behaviour on a 42 setup which only went away when I changed the exotic exhaust manifold for a Group 4 (less exotic) - and I wasnt even looking to cure the carb fault.... Seriously!!


Title: Re: S3 Air Filter Question.
Post by: Caracad on 18 October, 2015, 09:17:40 AM
I won't be messing with the carbs just yet.
I haven't had the car long (hence all the forum activity) and like most cars that have been little used it probably just needs driving.

My Gamma was much nicer after I took it on some long drives and started using regularly.


Title: Re: S3 Air Filter Question.
Post by: Jai Sharma on 18 October, 2015, 09:32:14 PM
I agree with what has been said here so far. You might also find lots of crud in the bottom of the carbs- just a thought


Title: Re: S3 Air Filter Question.
Post by: RobD on 25 October, 2015, 08:51:44 PM
I won't be messing with the carbs just yet.
I haven't had the car long (hence all the forum activity) and like most cars that have been little used it probably just needs driving. 

I think that's what's known in the trade as an "Italian tune-up" ;D  Usually involves a quick blast at max revs down the nearest dual carriageway, usually in the vain hope it will dislodge or unblock whatever is causing the carbs to misbehave...

No point in messing with the carbs until you know the valve timing and ignition timing are correct. After many years of messing about with old cars and bikes I've come to the conclusion fully reconditioned or new carbs are the way to go when looking for a set up. I've wasted hours and hours trying work around and compensate for worn out carbs. You'll be amazed at how easy it is to get an engine running well if you start off with decent carbs.
A good tip I got from a well known engine guru was to make large incremental changes when setting up carbs, this applies to jetting and also to adjusting air or mixture screws. When you do this you get a real feel for what the changes are doing and then you can back track in small increments until you achieve the required result.