Beta Volumex jetting with dcnf40 carb

[rossocorsa]

My very long term Beta restoration plods along with virtually no progress however in the spirit of misplaced optimism of an early finish I am trying to gather info and parts to perk up the engine a bit.

Basically my intention is to fit the smaller blower pulley, that I know Guy frowns upon, along with a 130TC inlet cam and a 40dcnf, from what I know it looks like it'll be 28mm chokes in the dcnf but what I need is sizes for jets and so on to at least get the engine running before it is set up properly.

Anyone have a set of figures to work from? Before anyone says fit a DCOE I know that is better but I don't want a huge boost in power just a better top end and would prefer to keep it looking standard under the bonnet.

thanks

Alan

[sumplug]

The DCNF is not my choice of carb for the engine. The float gets upset too much due to its location. I would fit the DCOE or IDF. With the volumex, you need plenty of air velocity. Dont now why you need to change the pulley wheel. Why not gasflow the head instead? More mass air you can get in, the better the power across the whole range.

Andy.

[rossocorsa]

Well others have had good results with the DCNF it apparently gets over the problem of the 36DCA being too small I know that a DCOE is better but I'm just wanting a bit more power - I'm not going into it too seriously and want to keep things looking fairly 'normal'.

I had a very rough HPE with a 40DCOE on it it went very fast but tractability was poor below 2000rpm. I never sorted it due to it being a complete and utter mess otherwise! I'm going to try the smaller pulley simply because I already have one.

edited by GC: please read Protocols

[Guy Croft]

The DCNF is fine on the Beta Vx but I cannot remember its jetting in that setup.

If I can find it I will publish.

GC

[rossocorsa]

That would be greatly appreciated if you happen to come across it

many thanks

Alan

[Guy Croft]

This jetting should be pretty close;

DCNF 40
chokes - 28mm
emulsion tubes F24
main jets 150
air correctors 175
pump jets 45
idle jets 50

Get it checked out on Phil Lanes dyno near me if you can. Don't alter that jetting without checking with me first (preferably not after it's all been messed up on a RR session!). if you can road and plug test so much the better, may tend to be lean/rich mid range or top end, we can deal with that quite readily here if I get accurate feedback.

GC

[rossocorsa]

many thanks for the info. I really appreciate it, I need to get the car ready now in terms of finding time to finish the body but this will give me chance to get everything together to get it running asap. I can get on now with stripping the dcnf and assembling to the right spec. with new parts where necessary

Alan