Carb I.D.

[GottaJet]

First off let thank all of you who have mastered these most complicated of cotraptions. As you have probably guessed by now I am completely ignorant when it comes to them. Oh yeah my question,I recently purchased this carb for 150 bucks and I would like to know what I have. All I know is that it is a Holley 750 4 barrel vac. secondaries elec. choke. I was also wondering if it would be worth putting on my boat (18' jet BBF) or if I should reach for my summit catalog and order a double pumper without the elec.choke. The only numbers I can find on it are 6R 6931 B1'
P-80 and the ones pictured below. Any help you can provide will be greatly appreciated. Thanks GJ:D
PIC 1http://www.***boat.com/image_center/data/500/1043carbsize-med.jpg
PIC 2http://www.***boat.com/image_center/data/500/1043carbsize2-med.jpg
PIC3http://www.***boat.com/image_center/data/500/1043carbsize3-med.jpg

[LakesOnly]

Don't know about your carbs details and I don't know what you've done to your 460 Ford, but I can tell you right now that even if it is stock with OT headers, you can get away with a Holley 850 DP mech secondary List 4781.
LO

[Hotcrusader76]

I will say that you're better off getting something that flows more fuel. That carb is a 4160 Vacuum secondary good to about 300HP. Without a rear jetting adjustment it would be very risque running here at WOT. Most of the time those stock rear plates are fix jetted at 76-78. Most BBF set-ups jet around 75P/84S. Also without a four corner idle on that carburetor you will have noticeable bog off the line considering it's stock circuitry.
Your best bet is to look up in Jegs and get yourself a 4781 as Lakes suggested or better yet an HP950, something with four corner idle for starters.
Good luck.
Note---I would not run that carb on a Marine BBF (WOT application), stock or not. Even aka"Hallet19"s Jetboat had a fairly mild BBF that ran a very warmed over vacuum secondary with secondary adjustable jetting and even that was borderline.
Could you rework that current carburetor you got for $150.00? Sure...it's a very common core for a performance build.
~Ty

[LakesOnly]

Here's a fair retail price on a brand new 850 list 4781:
New Holley 850 Carb On Ebay (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3183672701&category=317)
LO

[GottaJet]

Thanks for the info guys.I appreciate it..:D

[Moose]

Hotcrusader76, can that 4160 750 be converted to a 4150 750dp
w/ mechanical secondary's?. Also can a 4150 750dp be made to be boost Referanced?.
Moose

[Hotcrusader76]

You can boost reference all Holley carburetors, vacuum or mechanical.
The 4160 is very good budget core for a performance overhaul. Add a secondary metering block, convert it to four corner idle, knock the boosters out (install drop-legs), knock the horn off, add some acc.shot to the primary, rear notched float, and some good gaskets with a trued up face from a mill and you're sitting golden...
I do this modification about 40% of the time on overhauls.
Yes I could convert the vacuum over to a mechanical with an actual secondary squirter...but the time and labor far exceeds the cost of a true double pumper. Matter of fact the only components that would not be retained for the modification are the primary bowl, metering blocks, and mainbody..everything else would be tossed.....
~Ty

[Moose]

The reason I ask is, I have a 4150 750dp mech and a 4160 750
dp vac sec. I also have a HP830. I am looking to add a 8-71 to a
489ci bbc @ 4-6 lbs boost. and was wondering what would be the most cost effective? and best set up?.
Moose

[Hotcrusader76]

Well....at least all of the fuel bowls are interchangeable....:D:D
You have a start on two good set-ups...either dual HP830s or dual 4779 DPs.....the next step is getting them matched up with some new ones.
~Ty

[wbrenw]

This is starting to sound farmiliar. I too bought an inexpensive e-bay 4160. After trying to look up the numbers without any luck, I finally wrote an e-mail to Holley though their website. Not only could they tell me what it was, but what size jets, power valve, needles, the works.
Just taking a quick poll of Holley carb users with small block V-8's: What size primary jets do you have? I put an E-bay Holley 4160 on my 350 Mag (alpha) that has 66's on the primary side. The plugs are telling me I'm rich. I've got a stock motor, rebuilt to .030 over, on a 4800 lbs bow rider. I'd rather not have to start a collection of jets. What is everyone else running?
WW