Hi There,
We have a 1600cc Std twin port engine and have just fitted duel 40 DCNF's the carbs are in great condition and are just missing the jets. What would be a good starting point for Mains? Idle's? Acc Pump? It has extractors and also running 009 dist. Any suggestion would be appreciated.
Thanks
Jason
What vents???
oh didn't check that, will check out tomorrow.
Thanks
check out my thread if you want to see the jets/gaskets etc. Not sure what sizes are off the top of my head, have a look in the thread 🙂
&, ask Joel, he is a bit of a guru... 🙂
Thanks for your reply colonel mustard. As FROSTY mentioned, the 40dcnf's are in very good condition and they have 28 mm venturi's. Hoping to get some extra performance out of a standard 1600cc. Would these carbs also suit something like a 1776cc ?? Any input would be appreciated !!
I just chucked some DCNs on my 1915 with 28 vents.
Its running rich atm with 50 idles, 120 mains and 180 airs.
Have ordered some 45 idles and 115 mains so see how it goes with them.
You would prob be looking at 110 mains on a 1600 I think
twin DCNFs on a stock 1600 really is overkill
you can make it work but without a better cam its not really gonna make for a good combo
they're ideal for a 1776 though
as Simon said 115 would be around right for your mains with 28 vents and 40-45s would be a good starting point for idles
i think a single is heaps on a 1600.... but the linkage is the fun part.
Twins are way better than single, have done both on stock 1600 with slight head work and 1.25 rockers, trick is to not over scavange the exhaust side of things.
bitten by the bug..........several times
Twins all the way.
My Weber setup guide, actually published by Weber, has the following recomendations.
2 x 40 DCNF stock 1600 Dual Port 32 vent, 4.5 sec vent, 155, F24, 220, 45 idle and pump.
The listing for twins with 28 vents is for DCN's and is; 4.5, 125, F33, 185, 50 idle and 40 pumps.
I always use this book and only occasionally do I need to change anything.
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
Where did you get that book Matt?
Unreal Matt, thanks very much, thats what we'll start with.
Hey, have a good Christmas too.
trickysimon wrote:Where did you get that book Matt?
Can't answer that one.......well I could but then I would have to KILL you
😂😂
No idea actually, think Richard Holzl gave me my favorite reference page that is a photocopy that I use the most, about 20 years ago...... HA. It's really good, has quite a variety of combo's and engine sizes.
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
