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Author Topic:   Hey,KPLUGNUT?
steamatic racer
Dirt Full Roller

Total posts: 35
posted July 31, 2002 01:40 PM
I just had a carb. built for my motor,(C&S Specialties-St.charles MO.)They asked all about the spec.of the engine,gastype,track & etc.My ? is when I received the carb. it came w/ 76's jets. A paper for fine-tunning the carb. said("There are jets in the carb. now.Starting jet size is (76). Plug readings will get jets correct within two or three sizes foroptimum jetting.") Does that mean I should start w/ their 76-jets or since I know I had 84's in my "old" carb.,those?
THANKS TERP

KPLugnut
Dirt Freak

Total posts: 408
posted July 31, 2002 01:54 PM
Start with what they put in the carb. The reason for that is that they've (hopefully) flow bench tested EACH carb and set it up with exactly the right jet size it needs based on it's airflow readings. Don't just assume that since your old carb (whatever it was) had HUGE jets in it, that you should throw out their info and start there.
That is where the R&D of carb builders comes in handy. They do much of that work for you so you don't have to do much jetting 'guesswork' after getting the carb.

Hope that helps.

KP

steamatic racer
Dirt Full Roller

Total posts: 35
posted August 01, 2002 07:23 AM
Forgive me for asking is this,but your saying that the jetting that is in the new carb. is where I should start & adjust acording to the plug readings? And what does (R&D) mean? Trying to take all this stuff in!! THANKS AGAIN TERP

KPLugnut
Dirt Freak

Total posts: 408
posted August 01, 2002 07:28 AM
Yes, the jets that C&S sent in the new carb are there for a reason. They obviously did enough calculations based on the info you gave them about your motor to know that is what the new carb is going to need as a close starting point. That is why us carb builders always ask for so much info from our customers up front before building a carb for a racer.
And "R&D" is my way of saving my fingers from having to type out "Research & Development".

KPLugnut

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