Anyone using Summit 600cfm carb?
Thread Starter
Racer
Joined: May 2013
Posts: 421
Likes: 6
From: Chicago IL
Anyone else tune a Summit 600cfm carb?
If so, have you messed with the jetting?
I noticed a rich condition at WOT (11.5) on my wideband. Dropped secondaries from the stock 73 jets to 71 - no changes. Went down further to 69 - still around 11.7!!! At the same time, the primaries were running leaner than I'd like - anywhere between 13.1 -14.9 after pump shot. I took the stock (67) jets to 68 and the car was leaner - had no power accelerating...very flat. I heard stories of variances within specs on jets so I figured maybe that was it. Went to 70 jets and never got over 12.5 to 12.7 after shot - sometimes richer. Car ran a lot better. Thinking 69 might be the ticket. That would mean my jets are gonna be the same at 69/69. I might even drop the secondaries even more to lean it out to at least 12. That would mean my secondaries would be smaller than my primaries. Is that normal?
I noticed a rich condition at WOT (11.5) on my wideband. Dropped secondaries from the stock 73 jets to 71 - no changes. Went down further to 69 - still around 11.7!!! At the same time, the primaries were running leaner than I'd like - anywhere between 13.1 -14.9 after pump shot. I took the stock (67) jets to 68 and the car was leaner - had no power accelerating...very flat. I heard stories of variances within specs on jets so I figured maybe that was it. Went to 70 jets and never got over 12.5 to 12.7 after shot - sometimes richer. Car ran a lot better. Thinking 69 might be the ticket. That would mean my jets are gonna be the same at 69/69. I might even drop the secondaries even more to lean it out to at least 12. That would mean my secondaries would be smaller than my primaries. Is that normal?
Last edited by Jartanyon; Aug 13, 2015 at 08:40 PM.
Race Director
Joined: May 2006
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I know this is a Ford article but they dropped the primaries and just changed the secondary spring not the jets.
http://www.fordmuscleforums.com/indu...road-test.html
http://www.fordmuscleforums.com/indu...road-test.html
