Hey guys, I started having trouble with the carburetor on a car I recently picked up and I have no plans to rebuild it at this time. I want to replace it. I also have a fuel regulator question I will post at the bottom. The intake is a Holley Street Dominator and the current carb is a Holley 8047-2 4160 600cfm. Engine is an unknown year re manufactured 350(assumed) with a th350 trans. It does have the kick down cable connected to the carb. Since it has the cable do I order a carb with the ford kick down or is that something else? Will this intake take a square or spread bore carb without adapters? Would the 4175 be a good upgrade or should I stick with he 4160 or something else all together? Intake What goes where the block of plate is? Carburetor bottom (square bore?) Stack of assorted gaskets I found under the carb Fuel regulator question: To eliminate high fuel pressure as being the problem I picked up a Holley regulator. After receiving it I found it had 3 ports.. one in two out. I assumed it was for a dual feed but now I think the extra port is for a return line? I plugged that outlet and ran the other to the carb with a gauge between. I'm getting 4.5 into the carb. Am I defeating or harming the system by blocking off and not using a return line? I don't think the aftermarket tank I have has a place to return to. Once I get the new carb installed I am going to check to see what pressure I have without the regulator but I still wanted to know about the return line. Here is the one I purchased http://www.summitracing.com/parts/HLY-12-803
That regulator is a non return style. The 2 outlets can either feed both ends of a single 4150 or each separate to a dual carb setup. Plugging one outlet is fine. The intake has the square/spread bore flange. It should work with either 4 barrel config carb without adapters. Neither of those gaskets appear to be the correct one which is likely why they were stacked as a band aid. Check out an Edelbrock 9266. Correct shape and helps keep fuel bowls cooler. For a Chevy tranny I believe all you require is the appropriate bracket that mounts to the intake. Sounds like you already have it. The blocked off port on the side of the intake is for running a heat tube up to an OEM style air cleaner for a stock type application. Preheat the incoming air. Not something you want in any performance application so most guys block it off when installing an aftermarket intake on their rides. 4175's being spread bore style carbs will typically give a little better mpg at the expense of some bottom end power. The primaries are smaller and during street driving you are on the idle circuit and primaries most of the time. A square bore typically sacrifices some mpg but gives you bigger barrels up front to get the car up and moving harder. On a stock small block motor this might not be very noticeable. So it's really a matter of preference and what your intentions are with the car. The 600cfm 4160 you have is probably the most common first time upgrade to a stock sbc performance minded folks tended to do when I was younger. That and a set of headers. If your sbc has a mild cam, headers, etc. you could see some hp improvement running a Holley 750cfm vacuum carb 4150. The 600 you have would probably give better throttle response however. Depends on what you're after.
If you are using a stock mechanical fuel pump you won't need a regulator. If flooding is your problem it is most likely one of two things, either the floats are not adjusted right or there is crap in the needle valves. Have you tried adjusting the floats? if so and you can't get the flow to stop just pull the float bowl and clean the needle seats out. Other then that yes I would stay with the 4160 carb it is a good carb and simple. A carter AFB will also bolt to that intake if you don't like holley carbs. You don't need a ford carb with your chevy transmission, just hook the kick down cable up the same as it already is and call it a day.
Thanks guys this is exactly what I needed. .... It has an electric pump. The engine is mounted using the old style front hurst mount and I do not know if the mech pump would fit or I would most likely change back to it. porknbeaner how likely is it the power valve is malfunctioning? At any rate I will most likely play with this carb or sell it as is. This carb is dumping a ton of fuel into the intake and has already fouled the gas. The more I fool with adjustments etc the more afraid I become of damaging the engine.
If it is dumping a ton of fuel it is most likely a float problem, that carb with good needles and floats should take 5-7 psi easily. I have one here that I built with center hung float bowls that handles 7.5 PSI (checked with more then one gauge) but it is not your common everyday out of the box Holley 4160. If it is not a newer Holley with a power valve protector there is a good chance that the power valve is blown, it only takes on good belch back through the carb to pop one. A new carb like yours should run you about 250. best thing you can do is pull the float bowls and check it out. I know you can do it my granddaughter does it. Give it a whirl and let me know, you'll do just fine. Check your messages.
Sudden onset Holley vacuum secondary carb problems can usually be traced to one of two things: power valve or accelerator pump diaphragm. Parts are available at your local parts store and changing them out only requires the removal/replacement of the front bowl and metering plate. Like P&Ber said, any kid can do it. The problem is the alcohol in today's gas which stiffens the diaphragms in the power valve and accelerator pump. Happens sooner or later, but most often after the engine has not been run in a while. If the car was running okay before chances are it'll run just fine again after changing out these two parts. Use IDENTICAL parts to what's in there now, don't go for larger capacity parts which are for race cars. Won't help your street car one bit.
I must have ordered something different before checking back here... I ordered one from Summit but it wasn't that cheap! http://www.summitracing.com/parts/hly-0-80450 It looks pretty much like the one I have. Except mine doesn't have the little cover plate next to the valve adjustment. I went ahead and ordered a rebuild kit and the gasket mentioned above. I have rebuilt a couple before (2 barrel Ford and a 4 BBL Carter) so no fear of doing it, I just don't have the patience for it right now LOL I should be back up and running by tomorrow evening! P&B I got your message too late! Thanks for the offer though!
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