Holley Confusion

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It’s easy to tell if the shafts are leaking air, they either are and causing a problem or they’re not. With the engine running grab the primary throttle linkage and wiggle it hard while keeping it in contact with the idle stop screw. If the rpm changes the shaft is leaking. Holley sells bushing kits to fix that. For your engine a 600 classic 1850 vs will be a perfect driver carb. Classic has no adjustable air bleeds or emulsion or anything else, Just jets. Forget the slayer and brawler they are borrowed from the quick fuel line and for your application not necessary. The street warrior is a similar carb to the classic 1850 but is in a shiny modern finish. If I were in your position I’d use a 3310 750vs with electric choke. My 318 ran killer with that carb. You’ll have to tune whatever carb you put on there so pick one that you’re comfortable with.

Thank you! THAT’S the information I was asking for. You have provided the info to eliminate two of the four I was specifically asking about.

Am I correct in thinking the Classic has center hung floats? The Warrior looks a lot like my 1850 which has the side hung floats.

Thanks again.
 
Thank you! THAT’S the information I was asking for. You have provided the info to eliminate two of the four I was specifically asking about.

Am I correct in thinking the Classic has center hung floats? The Warrior looks a lot like my 1850 which has the side hung floats.

Thanks again.

The 1850 always has side hung floats. Not a thing wrong with those.
 
Thank you! THAT’S the information I was asking for. You have provided the info to eliminate two of the four I was specifically asking about.

Am I correct in thinking the Classic has center hung floats? The Warrior looks a lot like my 1850 which has the side hung floats.

Thanks again.
See post 30
 
What do you think is causing the wear? Dirty driving environment? I know I’ve seen them worn out but some guys run enough return spring that at a cruise your leg starts to throb because the pedal is pushing back on your foot so hard.

Come to think of it, I don’t think I’ve ever seen worn throttle shafts with billet base plates. The few I’ve seen were zinc or whatever materiel Holley used back in the day. They were pretty soft.

All of the above. Dirt, soft carb body material, heavy springs could accelerate that depending on the set up. Ultimately, it's a metal on metal interface with two dissimilar metals that doesn't get lubricated and isn't sealed or supported by bearings. If you drive enough, it will wear out eventually.

Which is not to say it's common, because it's not really common to drive enough to wear the thing out. But if it's an old carb, it's a legitimate concern.
The same reason every shaft wears prematurely, lack of lubrication and crud.

Exactly. And time.
 
They both have a single fuel inlet, side hung floats, and are classic 1850 style carburetors.
From Holley’s own web site

HOLLEY CLASSIC CARBURETOR - FACTORY REFURBISHED​

PART # FR-80458SA

Features:​

  • Vibratory polished aluminum for good looks, weight savings and long lasting shine
  • Performance upgrade for stock to mildly modified vehicles
  • Universal calibration for easy bolt-on performance
  • Factory preset electric choke for easy startups
  • Vacuum secondaries for use on wide variety of vehicles. Compensate for all vehicle weights, gearing & transmissions to allow smooth opening of secondaries.
  • Dual feed fuel inlets for constant high volume fuel delivery
  • Compatible with GM, Chrysler, and Ford A/T kickdown linkage. Additional parts may be required.
  • Power valve blow-out protection
  • Clear fuel level sight glasses
  • 100% wet-flow tested by Holley technicians to assure it arrives ready to run!
 
C’mon guys, this is a mild 318. With a 7-1/4 rear end and 2.76 gears I’ve already blown up twice. A double pumper isn’t what I need or want. Just want opinions on the four I listed.

I had discovered Holley’s refurb carb offerings a couple weeks ago and would like to save some cash, but the only 600 cfm carb in stock is a Street Warrior. But I don’t know how it compares to the other three I asked about.

The shafts on my current 1850 have a lot of slop. If carb cleaner is spayed near them the rpm’s go way up. It also never goes back to within 150 rpm of the original idle speed when the throttle is blipped. Transfer slots are square, mixture screws are 1.5 turns out and the floats are set correctly. I’ve been fighting with this thing long enough. I think a new carb is in order.

I would just like an opinion on the 4 carbs I asked about.

Thanks.

On my 360 I have an ancient Holley 750DP. It was old already in the mid 70s when I got it used. Yes the throttle shafts are pretty sloppy loose, so what; I'm not trying to idle it down to 500 rpm.

My guess , from your description, is that you got too much idle-timing, and your Mixture screws are not synced properly to your transfer slots, so then, once the airspeed gets up after a blip, the mixture screws won't quit flowing. Yes I heard you say your transfers were set square, but square is just a starting point.
So then, my advice is;
With a warmed up engine, a fully functioning PCV system, NO air leaks, and a disable VA; make sure the secondaries are fully closed but not sticking, then
Reset the timing to eight degrees, and
and reset the mixture screws to 5/8 turn out. then
increase the idle rpm to 650 in gear. Then
enable the VA, on the spark-port, and make sure the VA is NOT active at idle.
Finally, fix your power timing. You will have to modify your distributor, and until you do, the bottom-end will be lazy, and Power may be down, depending on it's current calibration.
BTW;
I also have an 1850/600VS that is just as ancient as my 750 DP.... which runs just fine. In fact, that 600 is my long-distance cruiser carb, specially prepped for fuel economy. I won't tell that it once got 32 mpg, in overdrive, on a certain 8 hour day trip, cuz some guys on here love to preach to me how that is impossible and then they call me a liar.. So if you heard that, it must be an echo.
Zillah is said to be at 850ft elevation. I'm at 900 to 950. So there's no problem there.
And as an aside,
your combo needs headers to take advantage of any overlap that your cam may have; and those alloy heads, working with headers, will really stretch out the power curve on the top. Yes a small cam may limit the dyno numbers, but so what; are you driving in the dyno room? With 2.76 gears, and a fire breathing combo, you can stretch first gear all the way to 60/65mph.
I wouldn't spend a Nickle on a different carb until after the headers are on.
And as far as your combo goes,
Your combo would run gangbusters with a higher than stock stall with those sick 2.76 gears. My winter 318 used to run a 2800, which I grew very fond of; and of course, I love DP carbs, spreadbores for 318s, and on a matching intake.
 
On my 360 I have an ancient Holley 750DP. It was old already in the mid 70s when I got it used. Yes the throttle shafts are pretty sloppy loose, so what; I'm not trying to idle it down to 500 rpm.

My guess , from your description, is that you got too much idle-timing, and your Mixture screws are not synced properly to your transfer slots, so then, once the airspeed gets up after a blip, the mixture screws won't quit flowing. Yes I heard you say your transfers were set square, but square is just a starting point.
So then, my advice is;
With a warmed up engine, a fully functioning PCV system, NO air leaks, and a disable VA; make sure the secondaries are fully closed but not sticking, then
Reset the timing to eight degrees, and
and reset the mixture screws to 5/8 turn out. then
increase the idle rpm to 650 in gear. Then
enable the VA, on the spark-port, and make sure the VA is NOT active at idle.
Finally, fix your power timing. You will have to modify your distributor, and until you do, the bottom-end will be lazy, and Power may be down, depending on it's current calibration.
BTW;
I also have an 1850/600VS that is just as ancient as my 750 DP.... which runs just fine. In fact, that 600 is my long-distance cruiser carb, specially prepped for fuel economy. I won't tell that it once got 32 mpg, in overdrive, on a certain 8 hour day trip, cuz some guys on here love to preach to me how that is impossible and then they call me a liar.. So if you heard that, it must be an echo.
Zillah is said to be at 850ft elevation. I'm at 900 to 950. So there's no problem there.
And as an aside,
your combo needs headers to take advantage of any overlap that your cam may have; and those alloy heads, working with headers, will really stretch out the power curve on the top. Yes a small cam may limit the dyno numbers, but so what; are you driving in the dyno room? With 2.76 gears, and a fire breathing combo, you can stretch first gear all the way to 60/65mph.
I wouldn't spend a Nickle on a different carb until after the headers are on.
And as far as your combo goes,
Your combo would run gangbusters with a higher than stock stall with those sick 2.76 gears. My winter 318 used to run a 2800, which I grew very fond of; and of course, I love DP carbs, spreadbores for 318s, and on a matching intake.

Wow! Thanks for the thoughtful knowledge dump.

Hmmm… Ok, I’m going to take another stab at making this carb work. I’m with ya on the tuning advice right up to where you’re suggesting I recurve my distributor. The car actually runs great from off idle to on the mat. It’s just that the idle is so inconsistent and pig rich. Plus my mpg really sucks. I do have mixture control on both needles but she wanders after you’ve moved the throttle at all. My goal is an idle, in drive, of 625-650, which, with my unknown, prolly stock, converter is 750ish in park. I’m not after smoking the tires at will until I replace the puny 7-1/4. Tired of replacing the carrier and spiders.

Not sure where you got the idea I had performance heads on this thing. I wish I did, but I’ve just got stock, non-closed chamber, run of the mill 318 ones. That said, would any of your recommendations change knowing the awful truth?

Really appreciate your helpfulness.
 
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Just an FYI on Holley carbs....their QC is crap. I'm working on a few projects a friend has and I bought a 750 DP for one of them. Right out of the box it was junk. Put it on the car and after starting it I knew right away something was wrong. The car smoked kinda heavy (overloaded on gas) so I started adjusting idle mixtures which helped smooth the engine out and calmed down the smoking but I had both idle mixtures screws turned all the way in on the front metering block, actual idle adjustment was coming from the rear block....that's one I haven't seen before. The carb came back off and after a complete tear down one thing I found were loose body to baseplate screws....I mean just barely snug and there was gasoline on the gasket where it should have been completely dry. While the baseplate was off I noticed that the rear butterflies were adjusted open too far which would explain the idle mixture issue. Bigger problem was the fact that the butterflies would not return to the closed position if opened all the way and rolled back to closed (I had the link bar removed while doing this). If I rolled them wide open and released the shaft, it would snap closed. I messed with this for a good half hour trying to get them to close on their own. Long story short, I wound up cranking the return spring on the the shaft one extra round to stiffen up the spring action and that would close the butterflies correctly. I also loosened the butterfly mounting screws so I could re-center them and got them to close better. Once reassembled and back on the car it took another time of coming off and closing the rear butterflies more to get the idle mixtures even all the way around. I also reset the float levels as they were too high. I hope this helps someone if they're having some weirdly stupid issues with a Holley carb. The engine now runs great and no more gasoline smoke out of the tailpipes.
 
That doesn't automatically mean that the timing is across-the-board right If it doesn't detonate at WOT, well, you got that going for ya...........
Nope, no detonation, anywhere. Car has run great at 14 initial for over a decade. Carb idle issues are a recent development and unlikely to be suddenly related to timing.
 
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