New to me Holley 4160 running extremely rich

[TerrapinWheeler]

Ditched the problematic Powertech injection system and bought a used 4160 off ebay. Cleaned thoroughly and installed stock rebuild kit with 67 jets, 6.5 powervalve, etc.. The motor is a stock 302. Starts and runs great, just tons of fuel rich exhaust filling the air. Set idle mixture with vacuum gauge and no difference. Fuel level is fine so I don't know what to do next. Any help would be appreciated.

 

[Mikey]

Once, I had a warped metering block do that. Does your carb have the small tube in the metering block for the accelerator pump circuit with two O rings? Some do, some don't. If yours does, I've pinched one of the O rings. Also, double check you have the right power valve gasket.

 

[BroncoJimbo]

Hmmm... I'm running a 57 primary and a 8.5 power valve. Runs great but still gets horrible gas mileage. This is on a 470TA and a mild 351W

 

[clintonvillian]

It is a 600 cfm carb?

Take this with a grain of salt because I am new at this, but a 67 seems large for everything I have read. Needs to be closer to 60 or even below that...

 

[TerrapinWheeler]

Once, I had a warped metering block do that. Does your carb have the small tube in the metering block for the accelerator pump circuit with two O rings? Some do, some don't. If yours does, I've pinched one of the O rings. Also, double check you have the right power valve gasket.

No tube on mine. I just used the gasket that came with the kit....are there different styles?

 

[TerrapinWheeler]

It is a 600 cfm carb?

Take this with a grain of salt because I am new at this, but a 67 seems large for everything I have read. Needs to be closer to 60 or even below that...

Yes 600cfm.

 

[Mikey]

No tube on mine. I just used the gasket that came with the kit....are there different styles?

Yes, some came with a tube and the gasket has a big clearance hole for the tube. Ones with no tube have a small hole. If no tube and you used one for a tube....that may be your problem.

Went back into my log book. I'm about 700 feet above sea level. When I ran a 4160 List 6919 600cfm I had 66 for primaries. That emissions carb had too lean of an idle circuit so I changed to a Truck Avenger 670cfm and run 65 primary and 73 secondary. Both had 65 power valves and plain steel secondary springs. Mine's a 302 with 85 Mustang GT aluminum intake and Hooker comp mid length headers, 2.25 dual exhaust. Timing 11-12 deg.

Hope this helps!

 

[Mikey]

Sorry, metering plate gaskets are different. in my prior post. There are two kinds of power valves and two different gaskets for them as well. They need to match. Depends on if the power valve has square hi flow ports or standard round holes.

 

[Mikey]

Hmmm... I'm running a 57 primary and a 8.5 power valve. Runs great but still gets horrible gas mileage. This is on a 470TA and a mild 351W

BroncoJimbo, that 470 is too small.

 

[Mikey]

Hey, two of you guys might be close to me....Lovettsville, VA....northern Virginia near Harpers Ferry.

 

[MS73HD302]

My 600 cfm Holley runs at 3/4 turns out from being seated with the same jets and PV you got. 15 initial timing and squared up transfer slots. 5.5 lb fuel pressure. Motors got original internals

 

[jckkys]

There are dozens of 4160 Holleys. What is the List# on the front of the air horn? A super rich mixture at all times could be a hole in the power valve diaphragm. I simply suck on mine to see if it holds vacuum.

 

[TerrapinWheeler]

There are dozens of 4160 Holleys. What is the List# on the front of the air horn? A super rich mixture at all times could be a hole in the power valve diaphragm. I simply suck on mine to see if it holds vacuum.

This is stamped on the right front of the air horn:

80457
0886

Seems like a pretty old carb.

 

[jckkys]

The 80457 is a universal 600 CFM, nearly identical to the 1850 that Holley has sold since 1958. Those 1850s were OE carbs on Lincoln/Mercury 430 engines. Years later it became the low buck universal 600 CFM. It should be easy to tune with few changes. The age is irrelevant. The primary throttle shaft will wear it's bore eventually with heavy use. Even that is easily fixed. That's the only wear any carb will see. Have you checked the power valve?
The size of the jets in one carb can't effectively be compared with others of the same CFM unless the the air bleeds are the same, and that spec is unavailable. A wide band A/F gauge would be needed.