40 trumpet/air filter query

[John]

Right, what's the optimum length for trumpets on a1.3 on 40's? Has head work and unknown cam. Can you run filters and trumpets, or just socks? I'm after some nice trumpets that don't look chavvy anodised yo! Any pics of "aesthetically pleasing" ones fitted? lol :thumb:

[paul james]

I have 48mm trumpets on my twin 40 cammed 1.3, they were fitted by the previous owner who worked for SBD, so I guess he knew what he was doing :)
You can run filters with trumpets, I originally had a SBD 'sausage' filter on mine but swapped it over for individual filter socks, as they are much easier to get on and off as theres little space between the carbs and firewall.

[John]

Any pics of your bay chap?

[paul james]

Sure, here you go:

http://homepage.ntlworld.com/paul.james21/SDC10550.jpg

http://homepage.ntlworld.com/paul.james21/SDC10552.jpg

[cornish]

Anyone know whether the Irmscher air box is any good in terms of flow? Or am I better off with the traditional trumpets and sausage filter set up?

[mowgli]

well, a decent cold air feed will be better than none, & the irmscher one was designed with rallying in mind & sock filters really weren't about in the early 80's.. the f1 cars used mesh!!!

[Royston]

Irmscher airbox was tuned for torque iirc

[chimp007_uk]

The trumpet length is determine by what rpm your tuning the engine to. Have a look a pulse tuning, you'll be able to work out what intake length you want. Obviously depends on whether the manifold is short or long.

[John]

@ Paul, what spec is your engine? :)

[paul james]

@ Paul, what spec is your engine? :)

Sport weber twin 40's, Irmcher manifold, Kent AST2 cam, 4-2-1 exhaust manifold etc. Rolling road tested a number of years back at a bit over 100bhp.