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Old 10-21-2012, 01:01 PM
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thanks for all your comments.

i have had a great day - took cobalts advise and when i stripped the carbs down the primary throttle plates where open more than the diagram you showed ( in the link ) so i reduce it to where it showed, also i turned the scre in on the base of the carb to open the secoundary plates just so slightly to allow a bit of air flow. i replaced the base gaskets (carb to supercharger ) and replace the pv with the new ones i had - although still being 6.5 ,

the dyno shop are going to measure the vacum first and and try to get it nearer ( if needed ) i also gave the carbs a through clean and blow out , seems to have sorted it as its now idling at 1135 rpm . still lumpy bit is as smotth as i could get due to the high lift cam - i didnt run it for long - prob a couple of minutes . as i dont want to wreck anything - i want the dyne shope to use their lambda sensors and heat sensors etc to see what mix im getting .

i had a few silly problems which wasnt helping - end of sprak plug lead was exposed and shorting onto the exhaust headers .

ok the specs on my carbs are .

- on the top of the carb horn - 1850-5 0209
i have converted them to have sec metering blocks although i cant fit in the rear of the front one due to them being back to back.

primary jets - 70
sec jets - 78

shooters .25
R107 booster

.65 pv ( for now )

both carbs have a orangey brown cam for the acc pump shot

i have a pair of each jets from 70 to 80 .

regarding the ecu not being needed - thats really up to personal prefernece, clearly as long as there is a spark then it will run. however when i go fuel inj the ecu will come into its own. also i can run some much more off of it. electric fans. rev limiter , wide band lambda sensors , water meth , launch control , and i can monitor any faults and the ecu will log these for fine tuning, which is a huge difference with that and a dizzy run engine. i dont want to be some where between by timing light a turening the dizzy a degree or so. with the ecu it can be exact , not a tiny bit out , thats the beauty of the ecu.

t bird , i know you keep referring to a ecu . not sure if you understand exactly it is i have. its not something i have pulled from a efi engine , i cant turn this off. i dont have a dizzy anymore due to the height of my supercharger. it wont fit - i have a dummy dizzy to run the oil pump . i particulay wanted this system due to its huge amounts of options and parameters.

its hard to explain te difference. ( i am sure you know the concept of a ecu ) but i have something that xrays the engine and reports the findings and a dizzy is like a blind massager who relies on hear and feeling, all you can do with a dizzy is stobe to time , pull plugs , and adjust approx. ( i know you can get close ) with the ecu i have a 100% safety net. once set uo this will not allow the engine to break. it will just shut off and repost a error. its what i want after spenging 10k plus on the enigne.

so if you state timing figures can you please be exact - ie. locking timing out , what does that mean ? i cant do that .

i will take a pic of my ignition chart which i can do what i want with and then i think you will be clearer.

thanks for all your help guys. nice to finally hear it idle a a sensible rpm
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