With sufficient air moving past this orifice, it will pull vacuum on the channel. Convert That 4160 to a 4150 So you bought a newer 0-3310 vacuum secondary 750 Holley for a great price, but later you realize it is the 4160 style with the secondary metering plate. Install all four screws, taking care not to tear the rubber diaphragm. If you tune the other way around using first or second gear as the base line , additional torque multiplication from the gearing exists. Following the part number is —2, which indicates that this is the 12th update or change for this carb; this likely means that the dies have been renewed 12 times. In some carburetors, you might find a small check ball in the diaphragm body. This is where the vacuum gauge and tach can really help.
The transfer slot adds fuel to compensate for increased throttle opening before the main metering system kicks in. This era also saw the introduction of the Holley three-deuce multi-carb setups on 427 Tri Power Corvettes and 440 Six Pack Mopars. A 4160 can be converted to a 4150 by adding a secondary metering block in place of the metering plate and swapping to center—hung-float fuel bowls. An O-ring seats onto the top of the housing. Holley itself has a huge website at Holley. Boosters help to pull fuel from the bowls as air passes through them. So much of the Holley carburetor romance has to do with an old-school look that includes that retro zinc chromate appearance.
Since this carb was recently purchased, I assume that it was built in 2004 or 2014. Place the rubber diaphragm into the lower housing and then set the base on your vise with the steel shaft extending through the jaws. The 1950s saw the introduction of the Holley Series 4150 4-barrel on the 1957 Thunderbird. When they are opened too late the spring is too heavy , you might not run into any drivability issues, but performance will be hampered, and the engine will feel a little sluggish. There are some other Holley parts not shown which included. Depending on the model, 4-barrel carburetors have either vacuum-operated secondaries or mechanical secondaries.
The 4160 series is a slightly less-expensive variant of the 4150, featuring replaceable primary jets, but with a thin metering plate on the secondary side and no replaceable secondary jets. These engines typically have four throttle blades four barrel. If it pops loose, be sure to reinstall it into its groove. The factory sometimes put both on and other times just the block number. A quick-change vacuum housing cover allows changing the vacuum spring without the need to disassemble the entire housing unit. The conversion kit foreground replaces the metering plate like on the 4160-style carb on the left and replaces it with a metering block like the 4150-style carburetor on the right.
Murphy brought it right back to life with a rebuild and a dip in his acid etching process that makes it look like new. This kit contains several different secondary diaphragm springs. Cars with automatic transmissions may need a slightly richer idle mixture setting to allow the engine to idle smoothly in gear. We wrote the first of many electronic fuel injection stories way back in 1988 in which we proclaimed that the carburetor, if not dead, was on the clear path to antiquity. Some carbs, such as the Avenger, have this as standard equipment. Where it gets interesting is that sometimes service carbs can have rare parts to them. Holley carburetors power every nascar sprint cup team and every nhra pro stock champion.
This prevents excess fuel spillover from sloshing out of the vent tubes. The lineup is quite extensive. The primary side has a metering block with jets, but the secondary side has a thin metering plate with pre-sized orifices. Much of this is determined by the tightness of the converter. We need to determine the areas of the jets and the power valve restrictors. Note this is an older factory carb with the vent linkage on the primary fuel bowl. Street Avenger carbs were designed and calibrated specifically for optimal street performance, with features including a secondary metering block, four vacuum ports for positive crankcase ventilation, power brake, spark, and vacuum accessories.
The fuel bowls will bring a little too. The classic Dominator has an aluminum main body with contoured venturi inlets for balanced airflow, a high-flow metering system, and annular boosters. Reducing the main jets from 75 to 70 is equal to a 13 percent reduction in flow area. The Series 4160 carbs also have a square-bore pattern but with more basic features. Basically, the larger diameter the wire, the stiffer the spring and the later the secondaries will open. This tends to disguise overall performance, particularly when the car is in high gear and you hit the throttle hard. Payment options paypal, visa, mastercard, american express, and discover.
For instance, a build date might be 1954. This side-by-side comparison of fuel-bowl styles makes them easy to identify. There is a Corvette service carb out there and I can't remember it's list. The Ultra is lighter for those concerned with minimizing weight and comes in several anodized colors. Make these changes very slight and note the effect on the engine. This can be repaired but will require new throttle blades.