Beaker Posted January 7, 2010 Share Posted January 7, 2010 Anyone got tips, or good at Tuning a DCOE Weber in Chch? Ive had no end of stress trying to get mine to run right, I had it Tuned on a Dyno, and they got the Mains and Air correctors right, but seem to have completely ignored the idle progession and trying to drive it at a steady speed under 2500rpm is near on impossible smoothly. The car is a 1275Gt Mini. The Carb is a single 40DCOE18 with 30mm Chokes, F16 Emulsions, 180 Air Corrector, 145 Main Jet, 35 Pump Jet & 40F8 Idle Jets It runs semi OK on the 40F8 Idle jets, but the Idle Mixture screw has to be about 8-10 turns out to get a smooth run, but it runs so rich the car is fumey to drive. Normally they should only be 1.5-2.5 turns out, according to experts the 40F8's are too small, so ive tried 50F6, 55F8 & 55F9 Idles Jets, They tend to idle nicer with 1.5-2.5 turns out (the 50F6's at best) indicating the size is about right, but the car is undriveable and difficult to get even up to the progression of the main circuit without missing and backfiring. Ive spent months trying to get it right. any ideas? Quote Link to comment Share on other sites More sharing options...
EFI_LC Posted January 7, 2010 Share Posted January 7, 2010 Anyone got tips, or good at Tuning a DCOE Weber in Chch?Ive had no end of stress trying to get mine to run right, I had it Tuned on a Dyno, and they got the Mains and Air correctors right, but seem to have completely ignored the idle progession and trying to drive it at a steady speed under 2500rpm is near on impossible smoothly. The car is a 1275Gt Mini. The Carb is a single 40DCOE18 with 30mm Chokes, F16 Emulsions, 180 Air Corrector, 145 Main Jet, 35 Pump Jet & 40F8 Idle Jets It runs semi OK on the 40F8 Idle jets, but the Idle Mixture screw has to be about 8-10 turns out to get a smooth run, but it runs so rich the car is fumey to drive. Normally they should only be 1.5-2.5 turns out, according to experts the 40F8's are too small, so ive tried 50F6, 55F8 & 55F9 Idles Jets, They tend to idle nicer with 1.5-2.5 turns out (the 50F6's at best) indicating the size is about right, but the car is undriveable and difficult to get even up to the progression of the main circuit without missing and backfiring. Ive spent months trying to get it right. any ideas? See me if you like as I have a heap of info including start up setting calculated by the experts for the engine sizes and usage etc. I'm at work at present but have all sorts of info. I will see if I can get it and give you a calculated startup tune..... Heres a list of some of the tunes racers use . D = choke size E = auxiliary venturi F = main jet, controls fuel mixture in the emulsion tube as cruise circuit is activated G = emulsion tube H = air corrector jet, affects only performance at high RPM I = idle jet, affects idle and progression circuit J = accelerator pump jet K = accelerator pump inlet valve with exhaust orifice (also called a discharge bleed). L = needle valve, affects fuel flow into the float bowl Reference D E F G H I J K L ----------------------------------------------------------- Weber (0) 30 4.5 120 F11 160 50/F11 40 50 ? Haynes (0) 27 4.5 130 F2 160 50/F11 45 0 2.00 Fitzgerald (0) 27 4.5 120 F11 160 49/F9 60 ? 1.75 TriumphTune (0) 28 4.5 115 F16 175 50/F9 35 ? - TriumphTune (0) 30 4.5 125 F16 180 50/F9 35 ? - Phillips 30 4.5 155 F11 200 45/F9 50 ? - C. Kantarjiev 28 4.5 110 F2 160 45/F9 - ? - A. Nugent (1) 28 4.5 120 F16 175 50/F9 35 ? - A. Nugent (2) 30 4.5 120 F16 180 50/F9 35 ? - A. Nugent (3) 33 4.5 125 F16 185 50/F9 40 ? - L. Bickel (4) 28 - 120 F11 160 -/F9 - ? - B. Mains (5) 30 - 120 F11 160 60/F9 50 ? - R. Lang (6) 28 4.5 125 F16 160 55/F12 45 ? - R. Lang (7) 28 4.5 120 F2 165 55/F12 45 ? - S. Ingate ( 30 - 120 F11 - 50/F11 40 ? - 40 DCOE-151 (9) 30 4.5 115 F11 200 45/F9 40 100 1.75 S. Ingate (10) 45 C. Arnold (11) 140 F11 160 55F9 Quote Link to comment Share on other sites More sharing options...
Beaker Posted January 7, 2010 Author Share Posted January 7, 2010 Thanks for the info, Ive based most of the settings from the 'Tuning the A Series Engine' Haynes book, by David Vizard, but really havent been overly successful Im short of a few different Jets to have a good set, I buy most of them direct from Italy so they take a while to get here Im quite happy to take it somewhere and pay for a bit of time to get it right See me if you like as I have a heap of info including start up setting calculated by the experts for the engine sizes and usage etc. I'm at work at present but have all sorts of info. I will see if I can get it and give you a calculated startup tune..... Heres a list of some of the tunes racers use . D = choke size E = auxiliary venturi F = main jet, controls fuel mixture in the emulsion tube as cruise circuit is activated G = emulsion tube H = air corrector jet, affects only performance at high RPM I = idle jet, affects idle and progression circuit J = accelerator pump jet K = accelerator pump inlet valve with exhaust orifice (also called a discharge bleed). L = needle valve, affects fuel flow into the float bowl Reference D E F G H I J K L ----------------------------------------------------------- Weber (0) 30 4.5 120 F11 160 50/F11 40 50 ? Haynes (0) 27 4.5 130 F2 160 50/F11 45 0 2.00 Fitzgerald (0) 27 4.5 120 F11 160 49/F9 60 ? 1.75 TriumphTune (0) 28 4.5 115 F16 175 50/F9 35 ? - TriumphTune (0) 30 4.5 125 F16 180 50/F9 35 ? - Phillips 30 4.5 155 F11 200 45/F9 50 ? - C. Kantarjiev 28 4.5 110 F2 160 45/F9 - ? - A. Nugent (1) 28 4.5 120 F16 175 50/F9 35 ? - A. Nugent (2) 30 4.5 120 F16 180 50/F9 35 ? - A. Nugent (3) 33 4.5 125 F16 185 50/F9 40 ? - L. Bickel (4) 28 - 120 F11 160 -/F9 - ? - B. Mains (5) 30 - 120 F11 160 60/F9 50 ? - R. Lang (6) 28 4.5 125 F16 160 55/F12 45 ? - R. Lang (7) 28 4.5 120 F2 165 55/F12 45 ? - S. Ingate ( 30 - 120 F11 - 50/F11 40 ? - 40 DCOE-151 (9) 30 4.5 115 F11 200 45/F9 40 100 1.75 S. Ingate (10) 45 C. Arnold (11) 140 F11 160 55F9 Quote Link to comment Share on other sites More sharing options...
EFI_LC Posted January 7, 2010 Share Posted January 7, 2010 Best place in Christchurch is Palmside Autos on Hoonhay road where they are the South Island agent for everything Weber Quote Link to comment Share on other sites More sharing options...
Beaker Posted January 7, 2010 Author Share Posted January 7, 2010 Best place in Christchurch is Palmside Autos on Hoonhay road where they are the South Island agent for everything Weber Might give them a go, will probably bust the bank account tho.. lol. Last time I took it to Harman's and I wasn't pleased with what i got for me $200 odd it cost me for them to put it on a Dyno and tune it Hope they dont charge $12 /jet $2.20 USD is what I normally pay Quote Link to comment Share on other sites More sharing options...
grdwalker Posted January 7, 2010 Share Posted January 7, 2010 wat r some good ones in auckland. preferably waitakere Quote Link to comment Share on other sites More sharing options...
EFI_LC Posted January 7, 2010 Share Posted January 7, 2010 Best place in Christchurch is Palmside Autos on Hoonhay road where they are the South Island agent for everything Weber Might give them a go, will probably bust the bank account tho.. lol. Last time I took it to Harman's and I wasn't pleased with what i got for me $200 odd it cost me for them to put it on a Dyno and tune it Hope they dont charge $12 /jet $2.20 USD is what I normally pay Thats where I buy my avgas from, they have a pump there. Dunno if you have heard of Dean Buist the rally driver but they run it and service all sorts of older rally cars which od course run webers so know there stuff. The other place would be Hawkes Motors or something like that on opawa end of Wordsworth st. I may have to look for a larger idle jet for mine to try as well but i have to get 6 at a time Quote Link to comment Share on other sites More sharing options...
Beaker Posted January 7, 2010 Author Share Posted January 7, 2010 Get your Jets from Gabriele David italiancarburetors@hotmail.com $2.95 USD for Idle Jets $2.50 USD for Main / Air Corrector Jets $5.00 USD for Pump Jets $12.00 USD for Chokes Weber Rebuild Kits are about $12 USD And only charges $5.00 USD for Shipping Ex Italy, takes about 1 week. Quote Link to comment Share on other sites More sharing options...
smokin' joe Posted January 7, 2010 Share Posted January 7, 2010 for baseline jetting, i have used Dave Andrews programme very sucessfully : http://www.s262612653.websitehome.co.uk ... ETTING.EXE if you are only using one carb, multiply engine volume Quote Link to comment Share on other sites More sharing options...
EFI_LC Posted January 7, 2010 Share Posted January 7, 2010 Ok I found my calculations sheet.... I need true max power revs - you used a dyno so this is easy. and need to know if its a mild engine - medium or race. cheers Graham Quote Link to comment Share on other sites More sharing options...
EFI_LC Posted January 7, 2010 Share Posted January 7, 2010 Remember before calculating things you need good spark, good even compressions and absolutley no vacuam leaks. Heres a guess at what I would try as a start up: 40DCOE18 with 30mm Chokes, F15 Emulsions, 180 Air Corrector, 135 Main Jet, 35 Pump Jet & 40F9 Idle Jets Heres what you have: 40DCOE18 with 30mm Chokes, F16 Emulsions, 180 Air Corrector, 145 Main Jet, 35 Pump Jet & 40F8 Idle Jets Heres what I run: 45DCOE13 with 38mm Chokes, F2 Emulsions, 200 Air Corrector, 145 Main Jet, 50 Pump Jet & 55F9 Idle Jets Heres what I calculated would run: 45DCOE13 with 38mm Chokes, F2 Emulsions, 200+ Air Corrector, 155 Main Jet, 50 Pump Jet & 60F9 Idle Jets I feel I would like to try the 60 Idle jets now I have my spark, I did try 65 ile which ran ok but my spark was weak and I had trouble running them. Hope this helps Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted January 19, 2010 Share Posted January 19, 2010 Easy to get larger jets for Webers? Quote Link to comment Share on other sites More sharing options...
VAGRANT Posted August 27, 2010 Share Posted August 27, 2010 HI there. i've been having probs with getting my carbs running right.... someone else set them up and im in the process of stripping them.. to see what setup ive got.. The carbs are twin 40 dcoe's and their on a toyota 2t-g 1600... the cams have been worked and the pistons are only slightly oversized. not sure of cams (i've lost the spec sheet...) currently the engine just gurgles under 3000 rpm but then takes off after 3000. The carbs did have 34mm chokes and ive got hold of some 30's to try.. Have you got any further tips? Quote Link to comment Share on other sites More sharing options...
Unclejake Posted September 1, 2010 Share Posted September 1, 2010 Yes. Check that the main jets are not too rich. Quote Link to comment Share on other sites More sharing options...
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