hewpt Casual Dubber
34 posts · joined Jul 2008 ·
I need a bit of help with my 40 dcnf , it has a hesitation just off idle anyone got any ideas
Help with a 40dcnf
Adsman Officially Full-On Dubber
393 posts · joined Jan 2007 ·
Do you have a 009 distributor?
What my garage isn't messy........Well chaos is a form of order isn't it?
Joel Now containing 100\% E-Wang
9,368 posts · joined Feb 2006 ·
x2 ^^
most likely u do as DCN and DCNF carbs dont have vac ports
can we get abit more info
is it a problem thats just started occuring? or has it always been so
engine size/ other mods etc
most likely u do as DCN and DCNF carbs dont have vac ports
can we get abit more info
is it a problem thats just started occuring? or has it always been so
engine size/ other mods etc
hewpt Casual Dubber
34 posts · joined Jul 2008 ·
Sorry I was a bit light on with details, yes I do have a 009 with an electronic ignition and yes the problem just started after I put a 1 5/8 header system on. the engine is a 1835 with an eagle 125 cam and head work blah blah blah. I realise the new system made a difference; I am just trying to come to terms with adjusting and working with a webber.
vassy66T1 Wow ... are U reading this?
2,120 posts · joined Jun 2003 ·
What size idle jet are you running?
From my experience when I ran a single 40dcn you need a fairly fat idle jet (maybe a 70 for your combo) but at least a 65.
My guess (from a little experience) is the idle jet. If your idle is big enough then I would look to mains. Depends at what revs the hesitiation is coming in.
The engine I had it in was a little different and only ran the semi-merged empi header set up.
Cheers
Marcus
From my experience when I ran a single 40dcn you need a fairly fat idle jet (maybe a 70 for your combo) but at least a 65.
My guess (from a little experience) is the idle jet. If your idle is big enough then I would look to mains. Depends at what revs the hesitiation is coming in.
The engine I had it in was a little different and only ran the semi-merged empi header set up.
Cheers
Marcus
hewpt Casual Dubber
34 posts · joined Jul 2008 ·
I have too get into it and check the sizing of the jets , i have also found the local webber guru who has agree to impart some of his wisdom. I have been dragging my feet a little on this one due to the arrival of my second daughter 3 weeks ago , the little ones are the greatest time wasters.
johny rotten Officially Full-On Dubber
366 posts · joined Apr 2004 ·
Do you have the manifold pre-warmer connected ?
Joel Now containing 100\% E-Wang
9,368 posts · joined Feb 2006 ·
what header did u have b4 the 1 5/8" ?
tahts a biggish header are the heads ported to match?
u may just need to bump up the jet sizes a smidge now and see what size vents u got in there
as johnny said manifold icing will make it run like a POS to
a dcn manifold that still has preheaters intact is the pot of gold thats for sure
tahts a biggish header are the heads ported to match?
u may just need to bump up the jet sizes a smidge now and see what size vents u got in there
as johnny said manifold icing will make it run like a POS to
a dcn manifold that still has preheaters intact is the pot of gold thats for sure
hewpt Casual Dubber
34 posts · joined Jul 2008 ·
The pre heat tubes have gone . the heads have been done and I ran the motor in on the heaterboxs and a extractor
johny rotten Officially Full-On Dubber
366 posts · joined Apr 2004 ·
Sounds like u might need a
I.M.D.I.U 😏
That is like a small electric heater.
I.M.D.I.U 😏
That is like a small electric heater.
Joel Now containing 100\% E-Wang
9,368 posts · joined Feb 2006 ·
ive got 3 manifolds with them all gone too
an electric heater elemernt around the manifold under the carb made it a totally different car to drive
night and day difference and the fuel economy improved drastically
once i get abit more time im gonna try and market some more
an electric heater elemernt around the manifold under the carb made it a totally different car to drive
night and day difference and the fuel economy improved drastically
once i get abit more time im gonna try and market some more
colonel mustard Son of Jim - Creator of Good
2,829 posts · joined Feb 2009 ·
Hey..... Joel.
This picture answered like 3 questions at once for me... the main one being, SO thats which way it goes on!!! haha. I was so confused.
will i need to run a heater like this, or just let it warm up more? do i need to run heat risers?
Where can i get a DCNF manifold!!!
This picture answered like 3 questions at once for me... the main one being, SO thats which way it goes on!!! haha. I was so confused.
will i need to run a heater like this, or just let it warm up more? do i need to run heat risers?
Where can i get a DCNF manifold!!!
hulbyw Insano Dub Head
819 posts · joined Sep 2009 ·
Joel
I have a 40dcn to go on a 1776 that is still a work in progress. It came on the manifold the other way around (fuel inlet on drivers side) with a pulley for the accelerator cable. Does installing it the way you have cause any issues apart from making the mixture screws a bit harder to access? Would certainly make life easier. Also, if my heat risers are blocked, where did you get the electric heaters?
I have a 40dcn to go on a 1776 that is still a work in progress. It came on the manifold the other way around (fuel inlet on drivers side) with a pulley for the accelerator cable. Does installing it the way you have cause any issues apart from making the mixture screws a bit harder to access? Would certainly make life easier. Also, if my heat risers are blocked, where did you get the electric heaters?
Joel Now containing 100\% E-Wang
9,368 posts · joined Feb 2006 ·
heater came with the manifold when i bought it but theres a mob called helios electro heat or something like that that can supply it
the mixture screws are still fairly accessable with it turned around, just made the throttle linkage so much easier
the mixture screws are still fairly accessable with it turned around, just made the throttle linkage so much easier
Joel Now containing 100\% E-Wang
9,368 posts · joined Feb 2006 ·
oh yeah jason, only DCNs can be put on backwards not DCNFs
hulbyw Insano Dub Head
819 posts · joined Sep 2009 ·
Joel. Any suggestions for dcn jet sizes for a 1776 with mildly ported dual ports, 149 cam, 009 and small bore extractors (using heater boxes)?
colonel mustard Son of Jim - Creator of Good
2,829 posts · joined Feb 2009 ·
Ah.. I will post a mock up photo in this thread soon Joel (or mms you.) I'm not sure my manifold is tall enough to clear the alternator. Also, the manifold has no bracket for mounting to the case.... Any idea's?? Also no heat risers left just the top pipe on one.
Joel Now containing 100\% E-Wang
9,368 posts · joined Feb 2006 ·
jason, mine didnt have a bracket either, most dont.
all i did was made one that went from one of the carb flange bolts down to the case bolt
i think its still bolted to one of my old engines somewhere
hulbyw, do u know what size venturies it has?
as a starting point with those specs depending on the size of the vents id start with 140 or 145 mains, 60 or 65 idles and 180 airs
all i did was made one that went from one of the carb flange bolts down to the case bolt
i think its still bolted to one of my old engines somewhere
hulbyw, do u know what size venturies it has?
as a starting point with those specs depending on the size of the vents id start with 140 or 145 mains, 60 or 65 idles and 180 airs
colonel mustard Son of Jim - Creator of Good
2,829 posts · joined Feb 2009 ·
Interesting/interested....🙂Joel wrote:all i did was made one that went from one of the carb flange bolts down to the case bolt
i think its still bolted to one of my old engines somewhere
hulbyw Insano Dub Head
819 posts · joined Sep 2009 ·
Joel- venturis appear to be 30mm.
hulbyw Insano Dub Head
819 posts · joined Sep 2009 ·
Had a closer look. They are 32's
colonel mustard Son of Jim - Creator of Good
2,829 posts · joined Feb 2009 ·
How can you tell. ? Darn Mazda taught me nothing about carbs.
Joel Now containing 100\% E-Wang
9,368 posts · joined Feb 2006 ·
its stamped on them
a 149 is bout the same grind as a W110 yea?
32s will be alright, on the smaller side of the scale but will make it more driveable, id see how it goes with them and that jetting
a 149 is bout the same grind as a W110 yea?
32s will be alright, on the smaller side of the scale but will make it more driveable, id see how it goes with them and that jetting
hulbyw Insano Dub Head
819 posts · joined Sep 2009 ·
Thanks Joel. A 149 cam is a Porsce Super 90 grind. Would expect it to be somewhere between a 100 and 110 grind. Have been told I can use 1.25 ratio rockers with it (havn't bought them yet) so must be fairly mild. Will see how it goes with your recommendations
colonel mustard Son of Jim - Creator of Good
2,829 posts · joined Feb 2009 ·
Joel Now containing 100\% E-Wang
9,368 posts · joined Feb 2006 ·
Jason, this is the linkage on my old engine thats now in a mates splitty
he bought a linx universal weber linkage kit and made this up with it and some alumnium angle from the hardware store
looks wild but it works
he bought a linx universal weber linkage kit and made this up with it and some alumnium angle from the hardware store
looks wild but it works
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Joel Now containing 100\% E-Wang
9,368 posts · joined Feb 2006 ·
this was the kit
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colonel mustard Son of Jim - Creator of Good
2,829 posts · joined Feb 2009 ·
think i could make that work???
colonel mustard Son of Jim - Creator of Good
2,829 posts · joined Feb 2009 ·
anyone have any other ideas on linkage???
colonel mustard Son of Jim - Creator of Good
2,829 posts · joined Feb 2009 ·
just hitting this with a bump for linkage ideas..