How do I make engine run richer or leaner???
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Joined: Dec 2007
Posts: 65
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From: LEESBURG VIRGINIA
How do I make engine run richer or leaner???
I have a 75 L48 with a q-jet. Edlebrock performer manifold, 2 1/2 inch true dual with flowmaster 2 chamber. Thats it.
Engine is backfireing on deceleration or basically when driving and take my foot if the pedal. Backfire through exhaust pipes.
How do I make It richer and/ or leaner?
Thanks Dino
Engine is backfireing on deceleration or basically when driving and take my foot if the pedal. Backfire through exhaust pipes.
How do I make It richer and/ or leaner?
Thanks Dino
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
You need to open the carburetor up and see what primary jets and rods it has. If it's stock it should be something like 72/44 or 72/46 (per Lars' tech paper). You can get a set of 74 main jets that will richen the primaries up across the board. This should take care of the lean popping in the exhaust.
BigBlockk
Later.....
BigBlockk
Later.....
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
An exhaust analyzer would be a good tool to see which way to go. Popping in the exhaust just might be from a rich condition not lean. Lean is normally accompanied by popping in the carb. Similar to situations with superchargers blowing or exploding on race cars. Check the tail pipe, a dirty carbon finger would indicate a fat condition not lean.
Burning Brakes
Joined: Apr 2007
Posts: 1,028
Likes: 1
From: SOUTH ELGIN IL
Will this help at all? I've never owned a QJet:
http://vetteworks.tripod.com/qjet.htm
Mixture info near the bottom. Lars' paper probably better from what i've heard. Good Luck
http://vetteworks.tripod.com/qjet.htm
Mixture info near the bottom. Lars' paper probably better from what i've heard. Good Luck
