What size is my carb?
January 19th, 2009, 02:49 PM
#1
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Join Date: Nov 2008
Location: Colchester,CT
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What size is my carb?
My 63 F85 with a 215 has a rochester 4 barrel on it, Its not the original one, I'm trying to figure out how big it is so I can decide weather a new one would be benificial, or if rebuilding this one will be fine. I'm not sure if its too big for my motor.
The number on the tag is
7025054
From decoding I know
70= Rochester
25= 1965
0= 49 state monojet
5= Oldsmobile
4= Automatic Tranny
None of it told me size, and the applications I found it listed for were either a 330 or a 400
If anyone posseses this knowledge, it would be grately apretiated. Thanks guys
-Ryan
The number on the tag is
7025054
From decoding I know
70= Rochester
25= 1965
0= 49 state monojet
5= Oldsmobile
4= Automatic Tranny
None of it told me size, and the applications I found it listed for were either a 330 or a 400
If anyone posseses this knowledge, it would be grately apretiated. Thanks guys
-Ryan
January 19th, 2009, 03:34 PM
#2
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Join Date: Jul 2008
Location: Manhattan, Illinois
Posts: 123
I have this information from HPBooks "Rochester Carburetors" by Doug Roe @1986
Model 4G: Throttle bore -- venturi size in inches
1-7/16--1-1/8 primary; 1-7/16--1-1/4 secondary = 486cfm
1-7/16--1-1/8 primary; 1-11/16--1-15/32 secondary =553cfm
1-9/16--1-1/8 primary; 1-11/16--1-15/32 secondary =692cfm
Your carb is off of a 64-65' 330cid. Carb # as per rebuild kit site says #'s7023054, 055 for 63' 215cid.
http://www.carburetor.ca/carbs/kits/CK515.htm
I would bet the one you need is the 486cfm. The 692cfm is probably for the 394/425 engines.
The 215cid only needs 400cfm @6000rpm though.
Model 4G: Throttle bore -- venturi size in inches
1-7/16--1-1/8 primary; 1-7/16--1-1/4 secondary = 486cfm
1-7/16--1-1/8 primary; 1-11/16--1-15/32 secondary =553cfm
1-9/16--1-1/8 primary; 1-11/16--1-15/32 secondary =692cfm
Your carb is off of a 64-65' 330cid. Carb # as per rebuild kit site says #'s7023054, 055 for 63' 215cid.
http://www.carburetor.ca/carbs/kits/CK515.htm
I would bet the one you need is the 486cfm. The 692cfm is probably for the 394/425 engines.
The 215cid only needs 400cfm @6000rpm though.
Last edited by Wireman134; January 19th, 2009 at 04:01 PM.
January 19th, 2009, 04:04 PM
#3
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Join Date: Nov 2008
Location: Colchester,CT
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Thanks wireman
Through one of those carb size calculations, the optimum size is a 372cfm, and the closest I can find is a 390cfm, so I'll probly rebuild the rochester on it now, and If I feel its too big i'll spring for the holly 390cfm (if funds permit)
Thanks again, and if anyone has anymore input, I'm still listening.
-Ryan
Through one of those carb size calculations, the optimum size is a 372cfm, and the closest I can find is a 390cfm, so I'll probly rebuild the rochester on it now, and If I feel its too big i'll spring for the holly 390cfm (if funds permit)
Thanks again, and if anyone has anymore input, I'm still listening.
-Ryan
January 19th, 2009, 04:23 PM
#5
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Join Date: Nov 2008
Location: Colchester,CT
Posts: 123
Ok, I'll have to see how its doing next time I see it. Its at my grandmas in here garage for the winter because I'm in colledge at the moment. I just found a vaccume leak to the carb when I started it sunday, so when I replace the split hose, i'll see what she needs. I'm pretty sure the throttle to venturi sizes are that of the 486 cfm.
January 19th, 2009, 04:58 PM
#6
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Join Date: Jul 2008
Location: Manhattan, Illinois
Posts: 123
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