Author Topic: Need a little help...  (Read 1924 times)

Offline Maintenanceman

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Need a little help...
« on: February 13, 2009, 02:27:59 PM »
Ok I just recently bought an edelbrock performer 750 carburetor. Ill need one that big for future plans but  for now I think Ill probably have to jet it down a little bit (probably to a 600-650). How to I figure out what size jets I will need to do this? and are holley jets the same as an edelbrock jet? By the way, I dont know that much about carburetors lol.


TIA
1985 Silverado K20- 355 SBC Vortec heads and a lil' cam...

Offline joesgarage71

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Re: Need a little help...
« Reply #1 on: February 13, 2009, 03:50:35 PM »
I dont know that much about carburetors lol.

Then run it as it came out of the box
78' K-20 355/SM465/twin stick 205 6" on 36's
14 bolt FF/big bearing Dana 44 4.56 gears

92' GMC C-1500 454/4L80E/14 bolt

Offline eventhorizon66

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Re: Need a little help...
« Reply #2 on: February 13, 2009, 04:02:33 PM »
You cannot jet a carburetor down in cfm (ie: from a 750 to a 600).  The size of your throttle blades and venturi are fixed and, in addition to the flow restriction posed by the boosters, are what determine the cfm rating.  What you can do is adjust the the jetting to achieve the appropriate A/F ratios.  You are in luck, because Edelbrock carbs have to be the hands down easiest to tinker with.  Get a hold of an Edelbrock carb owners manual and read it thoroughly; it contains everything a beginner needs to know to get started tuning.
'85 C10 SWB 350 700R4 TKO600

Offline Maintenanceman

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Re: Need a little help...
« Reply #3 on: February 13, 2009, 04:09:10 PM »
I dont know that much about carburetors lol.

Then run it as it came out of the box

Thats my plan as of right now and hopefully I wont have to do anything but Im just wanting to get all my ducks in a row on what Im going to have to do before I get new heads.
1985 Silverado K20- 355 SBC Vortec heads and a lil' cam...