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Question: Holly help

Bo Dillingham

Well-known member
Joined
Jun 23, 2001
Messages
121
Location
Cortland, NY, 13045, USA
Corvette
1965 crimson pearl (2002 cadillac?)
It's been years since my gearhead days, but I have a 65 Stingray with a 327 smallbock, highrise, tube exhausts, and a "Holly". In my former life, I had a 327 powered Chevelle with a "Holly 650 Speadbore" on a similar engine setup which I dearly loved. The Holly on my Corvette doesn't have any adjustments on it (like mixture adjustment screws). I don't like this carb, and I don't remember enough about old Hollies to just buy one and bolt it on. The "Holly 650 Speadbore" is all I remember about the one in my former life, but I do remember tinkering with the adjustments to maximize performance as well as fuel mileage. There seems to be a vast supply of used Hollies out there, and wondered if you have any suggestions as to what I should look for. Perhaps "Holly 650 Speadbore" is all I need to know?

Any advice will be appreciated,

BoDill
 
Have any idea which Holley is it?

Is the high rise aluminum and if so, is it a Winters intake? Do a search for Winters snowflake manifold. Once you know what to look for, they are pretty easy to identify.
 
Best guess

Thank you for your response.

(By the way, long ago I knew my way around an engine compartment, but haven't worked on cars for about twenty-five years. It will take me awhile to get back up to speed, and to learn about the new stuff out there. This engine setup was done long ago, and not by me.)

The manifold is marked "Edlebrock Performer 2101", and my best guess on the Holley is a model from the 4150/4160 series. I have a very old "Holley" book (from H.P. Books printed in 1972), and the photos in the 4150/4160 section look the closest to mine, although any adjustment screws, ports, etc. are blocked or non existent.

My objective is not to set a new world land speed record, but to be able to make adjustments to maximise fuel economy, or performance, etc. depending on my mood. I am now retired, and would like to get back into fooling around with my car.

Again, any help will be appreciated.
 
Do a search for holley 4160 4 bbl and how to adjust the idle air mixture. You'll need a vacuum gauge.

YouTube is your friend ;)
 
It's been years since my gearhead days, but I have a 65 Stingray with a 327 smallbock, highrise, tube exhausts, and a "Holly". In my former life, I had a 327 powered Chevelle with a "Holly 650 Speadbore" on a similar engine setup which I dearly loved. The Holly on my Corvette doesn't have any adjustments on it (like mixture adjustment screws). I don't like this carb, and I don't remember enough about old Hollies to just buy one and bolt it on. The "Holly 650 Speadbore" is all I remember about the one in my former life, but I do remember tinkering with the adjustments to maximize performance as well as fuel mileage. There seems to be a vast supply of used Hollies out there, and wondered if you have any suggestions as to what I should look for. Perhaps "Holly 650 Speadbore" is all I need to know?

Any advice will be appreciated,

BoDill

All Holleys have the same range of adjustments - what's the "LIST" number and the date code below it stamped on the forward side of the driver's side of the choke tower? That will positively identify the carburetor.

Holley "spreadbores" are replacements for Rochester Quadrajets, and won't work with your intake manifold. :thumb
 
Edelbrock 2101 - Edelbrock Performer Intake Manifolds for Chevy Details

Chevy 262-400ci Small Block V8

1955-86 Small Block Chevy 262-400
4-bbl Spread Bore Carb Flange (non-EGR)

John, if his manifold is a 2101, according to Jeg's it is a spread bore.
 
Holleyhelp

In answer to johnZ, the numbers on the choke tower are, 62 10-3 and 2629. Also, since there were at least a few owners before me, I have no idea how original any of the equipment is.
 
Holley help

To all,

After the response from "Toms007", I went to Ebay to look for a carb similar to mine (what I should have done in the first place!). In a matter of seconds, I found two;

I hope the links below will get you there if you're interested.

Holley Carburetor 6210 Spreadbore 650 CFM Double Pumper Mechanical Secondary | eBay

Holley Model 4165 Carburetor PN 0 6210 650 CFM Double Pumper | eBay

These carbs look very similar to mine, at least in outward appearance, Of the two, the "4165" is the best match. At any rate, now my curiosity is up as to the origin and "tunability" of this model carb.

If I'm better off just leaving it alone, I may want to replace it with one that I can fool with.

As usual, any advice is appreciated,
BoDill

P.S. To Toms007, by the way, the carb that you found on e-bay does NOT resemble mine.
 
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Bo,

I have a spreadbore on a 327 with an Edelbrock performer intake (the intake had models for either spreadbore (Quadrajet), or square bore carbs). It does have idle adjustment screws on the primary metering block, but outside of idle speed, choke pull off, secondary shaft "closed" setting, accelerator pump cams pick and hole (#1 or #2), those are about the only adjustments that can be made externally. If it has the center inlet bowls, fuel bowl level can also be adjusted.

Jet or power valve adjustment requires removing fuel bowls.

If the car does not run well, consider these issues I found on my car (after about 39 years of relatively trouble free 4165 operation) I found my car did not run well. It surged under constant throttle, would only run for about 7 minutes at highway speed (but would restart after sitting a few minutes), and did not start well. Eventually, I chased the problem down to a failed fuel pump. Due to mid-years elevated fuel tank level, fuel will gravity flow to the carburetor even with a weak or failed fuel pump. Not enough fuel to run perfectly, but sufficient for around town driving as long as the gas tank is relatively full. Needless to say, after chasing a bunch of what I thought the problem was, it really was the failed fuel pump. Also, since I had a center inlet fuel bowl conversion kit, the bowl fuel filter (the small sintered brass filter in the bowl inlet) was also pretty well clogged (found by trying to blow through it, when compared to a new one). So, you might consider starting there if your car does not run very well and is hard to start.

Give me an idea of what the issues are and maybe I can help. As indicated by other responders, there is a lot of information available on the internet, some of which I have found during my searches.
 
To All,

I have been away from this thread for awhile, and have around 70 responses to my other thread (Warm engine misses). Since I am trying to clear up the "misses" issue within the next few days, or weeks!!, I'm not going to do much more on this one until I get some results on the "misses".

However, I have learned a couple of things while on the other thread: 1.) My manifold is NOT a high-rise, and 2.) My Carb is a Holley 4165; that is a 650 Spreadbore Double Pumper.

Since one of my next moves was going to be a rebuild of the Holley, I have been looking around the Internet at articles, blogs, etc. etc. about the 4165 model Holley, and it seems that the news is not good. The first thing that nobody likes is the fact that the floats are not externally adjustable. The next thing is that they seem to go downhill after about ten years, as in they are not rebuild-able (this doesn't make sense to me, but that's what they say). So now I am concerned as to whether or not to try to rebuild the Holley, or get another model (perhaps even a good used one?). I remember from the old days (when I actually worked on cars all the time) that I really liked the Holley external float adjustments that my carb lacks.

Since the Holley website's "Carburetor Recommendation Page" came up with 20 carbs for a 327, I wondered if you folks have any suggestions. By the way, I am perfectly happy with the world land speed record being what it is, so I am not trying to set a new one. I just want a reliable ride around town and for road trips.

Let me know.... and Thanks,

BoDill
 
To All,

Tonight I spent some MORE time on the Internet looking at various sites regarding Holleys, and found opinions about Holley vs Q-Jet to go to the extremes in BOTH directions. Now, I remember from the old days that I liked Holleys, and found them easy to work on, (but as I said, this 4165 has NO exterior float adjustment) so I am wondering if there isn't a spreadbore configuration that would fit my manifold, and yet have the exterior float adjustment. If I Google images for "Holley Spreadbore" I get a lot of photos that look like mine, and a few photos that look a lot like mine but with external fuel bowl adjustment screws. Can anyone tell me if some carb other than the 4165 will fit my manifold while still being a Spreadbore, and having the Double Pumper functions? I will do a lot of research on this topic, but I thought one of you might give me place to start (like a 4160??).

(I think that I can contact Holley for an answer to that question, but I'm always leery of asking someone who wants to sell me something).

Thanks..... and more later,

BoDill

This is an edit on 08/06/16: From post #10, a quote from SJC, "since I had a center inlet fuel bowl conversion kit", I THINK answers my question as to whether or not one can convert a 4165 to have external float adjustment. If this is the case, does anyone out there recommend this switch of fuel bowls for external adjustment, or is not worth it? Will the same air cleaner base fit over the new bowls?
 
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If you have a 650 Double-Pumper on an engine with an Edelbrock Performer–which BTW is NOT a high-rise intake–you have a terrible mismatch. Also, DPs are poor choices for street use because they run so rich at idle and part throttle. You can make a DP run on the street, but it's a major project, requires a wide band O2 sensor in the exhaust and a lot of modifications.

If it were me, I'd put the 650 DP on eBay and buy a new vacuum secondary Holley for a street application. I'd say a 600-cfm would be good.
 
If you have a 650 Double-Pumper on an engine with an Edelbrock Performer–which BTW is NOT a high-rise intake–you have a terrible mismatch. Also, DPs are poor choices for street use because they run so rich at idle and part throttle. You can make a DP run on the street, but it's a major project, requires a wide band O2 sensor in the exhaust and a lot of modifications.

If it were me, I'd put the 650 DP on eBay and buy a new vacuum secondary Holley for a street application. I'd say a 600-cfm would be good.

Why would a double pumper run rich on the street? Is the secondary accel pump discharged like a fuel injector nozzle even though the secondary butterflies aren't being opened?

The Edelbrock Performer is higher than the old GM cast iron intakes, about 1/4" shorter than the Winters aluminum intakes used between 1962-1967. I'm not sure what constitutes a "high rise" intake? Maybe anything taller than the cast iron ones? Can you call the Performer an "almost high rise"? The Performer RPM is at least 1/2" taller than the 1962-67 Winters intakes and about 1/4" taller than the LT1 intake, so that might be called a "super high rise" intake.
 
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To All,

First, in post #12 I mentioned that I had learned that my manifold was NOT a high-rise, and I apologize for the confusion. Someone told me a long time ago that it WAS a high-rise, and I just plain believed them.

Next, I have had no problems with the carburetor before, and I'm not sure that I have problems now. As I said I would, I dropped the car off this morning at my favorite shop (C.A.R.S.) and will wait until I hear from them regarding the electrical stuff. My next move will depend a lot on what I hear from the C.A.R.S. shop.

With all that in mind, I will be reading and asking about "carburation" for the next few days with two things in mind; 1) I have always enjoyed the carb that I have (Holley 4165 SB DP), and 2) Since I have been away from "backyard mechanics" for a couple of decades or more, I am listening (read "paying close attention") to all the inputs that I am receiving.

Believe me, you all have my gratitude and respect. I vividly remember when I knew a lot about this stuff, and giving advice to people who ignored it. I don't intend to fall into that category.

As usual, thank you.....and more later,

BoDill
 
n the street, but it's a major project, requires a wide band O2 sensor in the exhaust and a lot of modifications.

If it were me, I'd put the 650 DP on eBay and buy a new vacuum secondary Holley for a street application. I'd say a 600-cfm would be good.

Hib,
I've heard DPs are poor street carburetors. I guess I'm dating myself. However, back in the day everything from a Z28's 302, 396-375, the Corvette 396-425, and the HO 427s came with a DP Holley.

Back then, a DP Holley is what they came with from the factory and we drove them on the streets. I didn't have any issues running them; even center shooters on a tunnel ram. Or the gear drives on the choke side.

By your mention of a wide band O2 sensor; is it modern engines that have issues? I do know, back in the day we sure didn't. Is this a modern thing?

 
There is nothing wrong with a double pumper unless it is too large for the engine. Plenty of nice street ready double pumper carbs on the market. I've run a few and never had issues.
 
I have a Quick Fuel 750 dual inlet race carb on my 327. Doesn't have a choke horn. One pump cold and the engine starts and runs immediately with a turn of the key (say, 1/4 of one crank), with some feathering of the throttle for the first 20 seconds until things warm a tad.

Plugs run perfect color, no fuel smell, no rich exhaust. WOT from a dead stop in 1st gear and the engine roars and the tires go up in smoke and revs hit the limiter immediately. No hesitation, no bog. Mash to WOT in 5th gear @ 2000 RPM and the engine pulls smoothly and steadily with zero hesitation.

What's not streetable about that? Plus 20 plus MPG @ 75 MPH with the 5 speed.

If a carb is properly tuned with suitable jet, power valve, and air bleed sizes, then all will be well. This issue about mechanical secondaries not being streetable is hogwash.

As mentioned above, SIZE is important. A mild 327 or 350 will be very happy with a 600-650 single feed carb because of the small throttle bores. A 750, single or dual feed can be appropriate as well, because the 750 uses downleg boosters, which make it more sensitive and responsive to low manifold vacuum than a 600-650 which use straight leg boosters.
 
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