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Need Help with weber jetting starting point

Old 09-07-13, 03:07 AM
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Need Help with weber jetting starting point

hi everybody im sorry if theres allready alot of threads about this. im from Denmark and somethings is lost in translation when im reading page after page in here about tuning a weber.
I have a 48 mm weber ida on a stock 4 port 13b engine with racingbeat exhaust.
the weber have been disassemblet ultra sound cleaned and all the surfaces been redone so everything is tip top and i have done the 3 progressionhole 0.8 mm
The engine is in a rallycar sa22 and i am doing dlidfis with 4 pin gm .

the thing i dont know is what setup i should start off with in the carburator because the previous owner hasent been very good at this either.
i have the following things in my drawers but i will order what i need to get a good starting point for jetting my weber.

aux ventury 45
chokes 42
e-tubes f-7 and f-16
main 150 and 250
air 165 and 195
idl ejet 70 f10
idle jet holder 120
needle 300.

Can i use any off this. and if not what should i buy insted.

and as a extra questin what spark plugs should i run the denso iridium ore the normal ngk.

Best Regards Rasmus Andersen Denmark
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Old 09-07-13, 05:48 AM
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an maybe whats a good starting point in timing the dlidfis

Rasmus
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Old 09-07-13, 10:15 AM
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for timing, start stock.

your jetting actually looks like it could be ok. i think with a 70 idle, it will be rich, but it should run. i would start with the F7 E tube, although i would test the F16 later.

for the main, i would start with the 250 fuel ,and 165 air, it should be very rich. the 150 main is probably going to be too lean

it is very hard to say what is optimal, as there are a lot of variables, but i would expect an idle jet that is 60-65, a fuel jet that is 180-210, and the air to be 130-165
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Old 09-07-13, 01:23 PM
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thank you but is there anyother jets i should order what about the f-3 ore f-11 e-tubes arent the f-3 supposed to be better?.
I actually also have som 55 f8 idle jets would that be better than the 70 f10
i also just got some 190 fuel jets
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Old 09-07-13, 02:48 PM
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use f11 to get it running. then switch to F2-F4 til you find the best for your motor. i will use a lower air jet 150 or below. make sure to check the bypass jet in the bottom of fuel bowl..it has to be zero
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Old 09-07-13, 05:01 PM
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Originally Posted by sa22rally View Post
I actually also have som 55 f8 idle jets would that be better than the 70 f10
i also just got some 190 fuel jets
try the 55's and the 70's and see what works better.

try the 190 fuel jet too, it actually should be closer than your other two choices.

personally i wouldn't spend money on an F11 etube, try it if you can, but the engine will probably want something else
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Old 09-08-13, 09:11 AM
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hi again guys so if im correct i should start with
f-7 e-tube
55 f8 idle jet 120 holder
190 main
and 165 ore should i begin with a 150. air.
is lambda 1 aka 1:14,7 the optimal mixture for a wankel engine.
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Old 09-08-13, 10:30 AM
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Originally Posted by sa22rally View Post
hi again guys so if im correct i should start with
f-7 e-tube
55 f8 idle jet 120 holder
190 main
and 165 ore should i begin with a 150. air.
is lambda 1 aka 1:14,7 the optimal mixture for a wankel engine.
i would start with 150 air.

for idle, you will want 12.2:1 to 13:1

part throttle cruise, 14.7:1

and wide open you will want something like 12.5-13.2:1
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Old 09-08-13, 11:40 AM
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great i think its pretty hard to find the answers you guys are giving me and its just what i needed. now as i recall the stock timing is 20 before and 15 after am i right ? with the dlidfis wouldnt it be better to do like 25 before and 5-10 after?
im using 99 oktane fuel
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