I am after some advice please

I have a Sylva J15 running a 1600 zetec se on 42mm direct to head Jenvey Throttle bodies, the engine is transverse mid mounted with the induction right behind the drivers head so space is an issue.
At the moment each airhorn (40mm long 45mm wide) is covered by an individual sock so i would like to improve this with either an airbox or dome type filter.
The baseplate for the filter/airbox would foul the fuel rail above it unless i fit a spacer to push the baseplate further away from the TBs however this would effectively lengthen the airhorn to 50mm overall length and the airbox would probably not fit between engine and bulkhead. It may be better because of the tight fit to shorten the overall length by fitting 20mm long airhorns hence the overall length would be 30mm.
From my understanding either or solution may help/hinder/or leave the engine as is

Anyone have any views or advice

Thanks

Nick M

From my understanding inlet tract length affects torque - longer = more, but not sure you would notice the difference. My bike carbs have a really short inlet manifold and trumpets and seem to work well.

Thanks
Seem to remember reading this at sometime now you have reminded me.
Think i will buy the spacers and fit a shorter air horn and at some stage have a power run to see what the figures say.

Ta

Nick M