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Snowboat
09-09-2002, 06:00 AM
Hotcrusader76. Or anyone else for that matter. Can you elaborate on the reason for jetting square or staggered. Is one better for blowers than the other?
Dennis Moore
09-09-2002, 02:48 PM
Staggered jetting is only done with big block Chevys and only when naturally aspirated. The big block has four intake ports that are short and four intake ports that are long. This requires a little creativity to get the correct air/fuel mixture to all of the cylinders. I would say that staggered jetting can only be accomplished correctly on an engine dyno with thermocouplers on each exhaust port.
Mercruiser comments in one of the service manuals to disregard staggered jetting whenever jeting a carburetor (for altitude or any other reason)so it must not be that important even to them!
Sincerely
Dennis Moore
Clown
09-09-2002, 03:05 PM
Dennis what if you are running a tunnel ram on a motor that makes almost 800 hp , I've had the motor on a dyno and always squired the jets!!!
Clown
09-09-2002, 03:08 PM
Almost forgot the motor is a 547 bbc on pump gas :D
Dennis Moore
09-09-2002, 04:51 PM
Sounds lie a real monster motor! If you have a large open plenum (like most tunnel rams) I don't think that you CAN stagger jet the carbs and tell the difference. The engine really can't tell if it has one large carburetor barrel or eight smaller barrels, it is simply pulling air/fuel from a large plenum. If you have a very small plenum or an individual runner manifold stagger jetting the carbs would probably become very important!
I hope you agree!
Sincerely
Dennis Moore
Hotcrusader76
09-09-2002, 06:38 PM
Dennis Moore:
Sounds lie a real monster motor! If you have a large open plenum (like most tunnel rams) I don't think that you CAN stagger jet the carbs and tell the difference. The engine really can't tell if it has one large carburetor barrel or eight smaller barrels, it is simply pulling air/fuel from a large plenum. If you have a very small plenum or an individual runner manifold stagger jetting the carbs would probably become very important!
I hope you agree!
Sincerely
Dennis MooreNeed I say more? That just about covers it!