Lancia Motor Club

Model Technical and Interest => Fulvia => Topic started by: Clyno on 26 November, 2012, 12:26:08 PM



Title: S1 Tuning
Post by: Clyno on 26 November, 2012, 12:26:08 PM
Gentlemen I’m in need of your advice..........i have a standard Series 1 coupe Rallye 1.3s and am contemplating changing the standard Air Box & filter for either foam air socks or my preferred option, a set of Gauze fitted trumpets. I understand that there may be issues with warm engine air circulating within the engine bay, and that this can be overcome with ducting cold air to the carburettors, but I was wondering if anyone has done this modification and what their findings were.

This also leads me on to another question....... I like to tune the engine to a fast road specification, but without spending a small fortune. Would anyone be able to advise me an how best to go about this. Thanks Trev.


Title: Re: S1 Tuning
Post by: lancialulu on 26 November, 2012, 01:41:58 PM
hi

Lancia already tuned it for fast road use!! ;D you could spend a lot of money and gain5bhp.....

best area to look at is to get the exhuast to breath better and going to gp4 with ported head is the simplest way...

re air box agian Lania worked hard to make this one work and has the added benefit of a fire trap. problem with open trumpets is spitting back can cause an engine bay fire. some racers gut the box and fit a big bore hose to the inner wing with a k and n filter....

tim


Title: Re: S1 Tuning
Post by: ncundy on 26 November, 2012, 04:18:25 PM
I wouldn't be too keen on running it with only gauze filters, you'll risk accelerated bore wear with no filtration. I'd agree with Tim, exhaust, cams and carbs. For anything meaningful I would think you'll want a budget of £1000+.


Title: Re: S1 Tuning
Post by: neil-yaj396 on 26 November, 2012, 06:05:36 PM
Surely a S1 would be better left in standard spec? Not one to tinker with I would say and gauze covered trumpets have been a no-no for years.


Title: Re: S1 Tuning
Post by: roddy on 26 November, 2012, 11:29:12 PM
Hello Trev

Just to reiterate what has been written - not a good idea to pick up the warm air from the radiator into the carbs, nor to run without good filtration.  Suggest that some benefits can be gained on the inlet side by ensuring that the inlet manifold ports blend on to the head ports and there are no flange faces showing, and similarly with the ports of the metalastic gasket.  The ports of the inlet manifold can sometimes have sharp edges where machined, and they can be blended and polished.

Big gains can be obtained on the exhaust side and a Fulvia engine can breath much better with some exhaust changes.  Although expensive, a proper Group 4 style manifold and system is worthwhile.  My own experience is with the one offered by Omicron (admittedly on a 1600cc engine), and a middle pipe for a Series 1 car is available (it is straight whereas the Series 2 is curved round the different subframe rear cradle of the 5 speed gearbox).  The system also offers good gains in torque, and that is important :-

If you make the engine very 'peaky', you will find that it will drop off cam with the wider ratios of the 4 speed box, hence the importance of keeping good torque.

Regards - Roddy


Title: Re: S1 Tuning
Post by: Clyno on 28 November, 2012, 10:53:12 AM
Gentlemen,
Thank you all for your valid constructive advice. It’s much appreciated.
Trev.


Title: Re: S1 Tuning
Post by: angelorange on 31 December, 2012, 03:32:55 PM
Weber do a double mesh (very fine gauze) trumpet covers which (outside of a harmattan storm) work as well for filtration and air flow.  Main issue is getting cold air past the upright radiator.  Race cars often had rads made lower such as the F&M one off machines.