4150 or 4160?

[Brandy]

I have a Holley dual feed 750 CFM elec choke carb. I was reading an article which stated the 4160 carbs have side hung floats and the 4150's have center hung floats. My carb is a 3310-3 list # and has center hung floats in both bowls. Which is it? 4160 or 4150? To further confuse the issue it has a Elkton 12R-4470B base plate. Primary has a metering block, secondary a metering plate.
I was under the impression that the 4150 has two metering BLOCKS. Am I wrong? Or am I missing something? Like this carb is a mashup? Or what?

EDIT:::: After reading more of the article I must have a 4150 carb.

 

[R/T Boy 67]

A 4150 carb has two metering blocks. A 4160 has one block and one plate. 3310 -1 was a 4150. All other 3310 carbs that came after 1 are 4160

 

[Larrywre]

R3310-3 is a 4160 from holley techlibrary_carb_numerical_listing.pdf
Not sure on the second question.

 

[Brandy]

Okay, why does the Holley disassembly guide state that all 4160's have side hung floats and all 4150/4500 series have center hung floats like mine has? And center top needle seats. And 1 block and 1 plate? Is this a carb that has had 4150 bowls added to it? Perhaps?

 

[R/T Boy 67]

That information is just plain wrong. All 3310 4160 type carbs that I have seen have center hung float bowls. I have a3310 -2 on my own car. It is a 4160 that I added a secondary metering block to.

 

[Brandy]

That information is just plain wrong. All 3310 4160 type carbs that I have seen have center hung float bowls. I have a3310 -2 on my own car. It is a 4160 that I added a secondary metering block to.

Oh I don't doubt it. But what I'm reading is straight from Holley. With pictures. In color. They must have screwed up somewhere... oh, and the rebuild kit I got is missing the base plate to carb body gaskets...

 

[66Satellite47]

I had a couple of 3310-2 that were center hung float bowl with secondary metering plates.

 

[lewtot184]

secondary metering plates (no jet block) is 4160. has nothing to do with bowls.

 

[33 IMP]

A 3310-any# is NOT a double pumper. It does have a double fuel inlet. If you truly have two accelerator pumps, you definately have a mashup.

 

[Brandy]

AhhhHA! Thanks.. 4160 it is....

 

[rlem1977]

Found the following from this site:
http://www.rodauthority.com/tech-stories/fuel-cooling/historic-holley-carburetor-milestones/

In 1965, the new list number 3310 (a model 4150 carb), made its smash debut on the 375-horsepower 396ci engine that came in the 1965 Z-16 Chevelle. It only lasted for one year as an OE production carburetor, but it had been such a huge success as a performance carburetor that Holley released it as an aftermarket carburetor in 1966, available to the masses. The 3310 started out as a 4150 model with primary and secondary metering blocks and in the 1970s, Holley changed it to a 4160 model with a secondary metering plate.

And this:

https://www.musclecardiy.com/tech-tips/complete-history-of-the-holley-carburetor/

The 4150 series is the original 4-barrel modular design, which features metering blocks and replaceable jets on both the primary and secondary sides. The 4150 series is available with either mechanical or vacuum secondary operation.

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.

 

[moparwacko]

If its a 70's era 3310-3 you've struck Holley gold.
It's the quintessential performance street carb ( in it's day), infinitely tuneable and customizable. It is my go-to for B applications.
Good find!

 

[33 IMP]

I'm curious about your bowl screws. Somewhere along the way, holley changed from screwdriver slot screws to capscrews,so that amateur carb tuners could more easily warp main bodies and strip out bowl threads. The picture of moparwhacko's 3310-3 brought the subject to mind, as my -1 has screwdriver slots. Does anybody here know when the crossover was, as an indicator of age of a carb?

 

[Brandy]

If its a 70's era 3310-3 you've struck Holley gold.
It's the quintessential performance street carb ( in it's day), infinitely tuneable and customizable. It is my go-to for B applications.
Good find!
View attachment 611539

1970/1980/1990/2000. So yeah. a good one. I can simply add another metering block to the secondary side and it becomes a 4150. Add a fuel bowl with an accelerator pump and it becomes a double pumper. The date code is 4 digits so it's newer than 73 and the code is 2400. So August of one of those years...

 

[Brandy]

As far as screws go, mine has 'em. Don't have a clue when they began though...

 

[Brandy]

So, the Holley tech guy says this is a 1990 Holley 4160 dual feed, vac secondary, Quick Change Vac pump spring cap, elec choke, one check ball in the vac pump body, no check ball in the nozzle, and the fuel bowl needles have been swapped out for another kind that has no adjusting nut and screw but has the screwdriver slot in the top and a lock down nut. He says it's a good performance carb for street duty and is customizable through bowl changes, adding a secondary pump, changing metering plate to a block, different nozzles, needles etc. Thought it was cool that somebody had added the quick change cover.

 

[Brandy]

Question? I have an electric choke but also parts for a manual choke. They all came off the same carb. WTF?

 

[old guys rule]

the 3310 and 3310-1 have secondary metering blocks rather than metering plates and are 780 cfm. the -2 and above are 750 cfm. likely someone has changed to a metering block on the secondary side. Either way you are good for a street vehicle. A metering block on the secondary side just gives more tunability for the secondaries if you are seriously racing.

 

[hangn0ut]

Can't make a double pump. Has no provisions for squirters. Among other things.

 

[old guys rule]

you probably wouldn't be happy with a double pumper on the street anyway, they are terrible on gas mileage and will prematurely wear out your rings. adding a metering block to the secondary side won't make it a double pump anyway, just more tuneable. make sure you get the right block, not from a double pump carb. you can convert a 3310 4160 to a 4150 by adding a secondary metering block with kit no. 34-6.