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Carb Swap Questions: Edelbrock to Summit

4379 Views 97 Replies 22 Participants Last post by  swooshdave
When going from an Edelbrock 1406 to a Summit 600 will the Summit bolt right on? Are the bolt patterns and such all the same? Hoping to place one order and not several. Thanks!

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Yeah, how about a pix from directly above?
If I take it off again I will definitely get better pictures of how the butterflies fit. And I want to compare as to how it compares to the Edelbrock.
Maybe the transition slots are too exposed. Ideally they should only be barely peeking out.
They say to only tighten to 50-60in/lbs which isn't much. I do want to crank down more. I don't think I'll warp the flange unless I get ugly on it. But since the spacer is so squishy I think it can take more.
I use 60 in/lbs. Much more than that and you risk distorting the throttle body which can bind the shafts and throttle plates
Fast idle cam is floppy when choke is open. So screw isn’t in play.
I use 60 in/lbs. Much more than that and you risk distorting the throttle body which can bind the shafts and throttle plates
Is that with a squishy 1/4in spacer?
I think I need to put a torque wrench on mine. I just tightened it until I was sure it was sealing. I bet it's too tight. Don't know if my wrench measures as small as 60 in/lbs.
Will your ft/lb wrench go down to 5 ft/lbs? 12 in/lbs to a ft/lb. kip
Will your ft/lb wrench go down to 5 ft/lbs? 12 in/lbs to a ft/lb. kip
Five is barely finger tight. Like two finger. The littlest ones. No way that seals with this spacer. With a hard spacer? Sure. But not this soft one.
Sorry Dave, I was responding to Clay, he wondered if his wrench would measure as low as 60 in/lbs. I wondered if he had one that would read 5 ft/lbs as that would be the equivalent of 60 in/lbs. kip
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Sorry Dave, I was responding to Clay, he wondered if his wrench would measure as low as 60 in/lbs. I wondered if he had one that would read 5 ft/lbs as that would be the equivalent of 60 in/lbs. kip
Thanks, Kip. I'm sure it does, so I'll give it a shot. I know I"m well past that. As Dave said, the mushy spacer provided with the carb requires more force than that. I'm not so tight I'm bending the flange. Just wanted a good seal.
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Even though I’m currently running a Holley I much prefer the simplicity of the rod and spring setup. Changes take minutes and you don’t end up with gas everywhere.
Even though I’m currently running a Holley I much prefer the simplicity of the rod and spring setup. Changes take minutes and you don’t end up with gas everywhere.
That is the one benefit of the Summit, if you do want to change the jets you can do it wet. I never understood why Holley made the float bowls the way they did. Better chance of leaking and if you do want to make a change on the car you've got a mess.
That is the one benefit of the Summit, if you do want to change the jets you can do it wet. I never understood why Holley made the float bowls the way they did. Better chance of leaking and if you do want to make a change on the car you've got a mess.
I agree and feel like the summit is the best of both worlds. Too bad about the high idle problem some folks have.
I agree and feel like the summit is the best of both worlds. Too bad about the high idle problem some folks have.
I have a feeling I'll get it solved.
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Did you get it it to idle down? What did you find?
I had a high Idle problem at first with my Summit carb. Then I tried turning the stop screw out on the secondaries. You have to remove the carb for this as it is only accessible from underneath. Solved the high idle issue straight away.
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I’ve run both on my car. I would say the Summit seemed to feel slightly better if I had to pick something out between them but not earth shattering. I went back to the Edelbrock only because I have a tuning kit for it. The Summit I forget either was rich or lean at part throttle and a jet kit was like $100. What I was disappointed by theSummit is a lot of rough areas inside the boosters that were not deburred. I feel there’s a lot of room for improvement. Over all the Edelbrock is made and finished much nicer.
Color me stupid: wouldn't rough areas increase turbulence and improve mixture?
Color me stupid: wouldn't rough areas increase turbulence and improve mixture?
Not in the boosters & venturii, no. That said, turbulence is a deeeep rabbit hole 😉
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