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My engine is ready for a carb. It is a 390 bored 30 over with flat top pistons. I have installed a Lunati VooDoo cam with intake lift of .503 and exhaust lift of .524. I have installed Roller rockers with 3/8 dia pushrods ball/cup and Lunati hyd lifters. The bottom end is pretty much stock other than being bored .030 over. I have installed an Edelbrock performer intake and upgraded the dizzy to pertronix ignition. The Heads have had bigger valves installed along with Lunati springs to match the cam. I have not yet changed the rear gear, I am wanting to say it has a 275 gear cant really remember. I am going to go with something between 355 to 4 once I get to that end of the car. For anyone with experience with the FE's what size Carburetor do you all think would work well with my engine?
 

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I used a well built Holley 750cfm Double Pumper with a Pro-form main body and throttle plate its jetted for my 428 and runs great. My only issue was the a/t kickdown linkage wouldn't work with the Pro-Form linckage, but not to worry, Lokar makes a cable kit thats just the trick. yours being a 390 i'd go with the same set up just in a 650 cfm mine runs vaccume secondaries and feels like a monster under the hood.
 

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Every brand has more than one that will work well on your FE. Your target for a warmed-over street 390 in a Galaxie would be 500-650 CFM with vacuum secondaries. A prime choice would be the original large-bore 4100 series as many of them were equipped with from the factory. Awesome carbs. If you are the handy type, start hunting a good core and do a full rebuild yourself.

My current pick for this type of duty in a new carb is the 8600VS from Summit, which is 600 CFM, vacuum secondaries, with many of the 4100's unique features, and yet uses common Holley parts. Very reasonable cost (they're about $240 right now) and a responsive runner.

Beyond that, take your pick of the popular brands for a similarly-sized unit, tune it in for your car and have fun.

David
 

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The 4100 is a good carb though I heard it was actually more like 550 cfm than the advertised 600. So it may be a tad underpowered for your new cam.

The problem I had with it is it won't fit on an Edelbrock Performer. The 4100 and its spacer is too big for the base and air gets sucked up from underneath.

Also, the Performer intake is quite a bit taller than the stock intake so there may be a problem with the air cleaner hitting the hood or the throttle linkages coming at a bad angle. You could leave out the spacer but then there is no place for the PCV to go.

Basically Edelbrock has a little scheme here to make you buy their carburetor and they have been pretty successful with it.
 

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A 390 has always been an in-between motor for 600 vs 750

However, looking at your intake and assumed rear gear and expected change later, I would lean toward a 600, notice I said lean, not "you need a 600".

Vacuum secondaries are a good match for a tall geared, AT torquer, so all that is left is to choose the brand

Edelbrock has nice throttle response and idle, typically is drop on and go, but almost always is down on WOT power compared to a comparable Holley

Holley's are tried and true, a stock 390GT 600 would be great, but if going new, an 1850 (600 vac sec) with electric choke and Ford kick down would be a nice addition. Steer away from the Street Avenger series, I dont think they make a 600, but their 670s are miserable for a dead spot in the transition circuit, the standard 1850s dont have that problem

A 4100 with a spacer to clear the linkage is a nice piece too, but you cant buy them new and they dont have electric chokes, which adds to the complication if you dont have a hot air tube

The Summit carb is a good piece, but like Holley's first release of the design, if they stop making them, will you be able to buy rebuild kits etc?

My choice would be the Holley based on the slight HP edge, but I have used a lot of Edelbrocks, one on almost an identical combo to yours and they work well.

Now here's a question what if you went with a 3310 (750) or an Edelbrock 750? Would it be bad? Not at all, it will work just fine. I run a 3310 on my 390 4x4 F-100 and there is no loss of low end, no issue whatever. Nor would yours have any.

The only reason I don't say you need one is because of your intake and rear gears now. The Performer is a bit of a cork and will never USE the 750 cfm because it just doesn't flow, so why bother? However, if you do expect to step up to an Edelbrock RPM intake later and you do the headers and ignition work I mention below, the 750 would be a real nice match to allow those pieces to breathe. The intake swap alone will add 20 hp with no loss in torque

A couple of comments though, specifically two things you didn't mention that will make all the difference on a street FE

1 - Recurving the distributor, not just a Pertronix. if you haven't, get it done, it's worth its weight in gold. An FE distributor has too much advance and it comes in way to slow, so no performance, then when you are screaming it over advances losing power and increasing the chance for detonation. If you recurve that distributor to 24 degrees mechanical advance, all in by 2800 and set initial to 14, you will think you picked up 2 more cylinders in normal driving.

2 - Headers - If you are not running them, consider spending the money on a set of ceramic coated headers of any brand, any style. FE log manifolds are the worst, you could literally lose over 40 hp with a set of manifolds. Ceramic coating looks pretty, keeps them from rusting and keeps heat down under the hood.

Worth waiting if cash is tight. When considering them, a 400-ish hp FE will gain 40 hp at the peak and improve the whole curve when going from CJ manifolds to long tube Hookers in a Mustang. There is probably (I havent tested) 20 hp difference between CJ manifolds and stock logs. So needless to say, headers are good :)
 

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I had one of the early Holley Projection units on my 69 Bronco, liked it just fine till the cpu went up in smoke one day leaving me stranded. Took it off and it's still laying around my garage in a box somewhere.
Mike
 

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That's the one you use from either the 4v or 2v version, made through the '70s, and by Holley into the early '80s. I've done a couple as it just screws right on. They are everywhere, as nearly every 2100 had them, and you can find 'em on Fleabay for $5-10.

BTW - the point about the 8600VS is that the wear items are all standard Holley. The unique items that make them run so well are non-wear, so even if they quit making them tomorrow, you should have no issues rebuilding them 50 years from now. And, it will bolt on a standard Holley-pattern manifold. A great carb design made better. ;)

I rarely engage in 'favorite carb' threads, as the subject is fierce with loyalty to the point of fist-fights. That said, I maintain my position that any good carb in the parameters that you've been given will work reasonably well if tuned properly. And, yes, the single worst cork in the FEs is the exhaust. All else is strangled by that.

David

The 4100 series had both mechanical and electric choke, as in this 1965 example from the MustangTek site. They were commonly available in the 1.08" (480 CFM) and 1.12 " (600 CFM) sizes, and the occasional performance 1.19" (670 CFM) version. I have seen the 1.12 version make almost 450hp on the dyno, indicating anything larger (of a good design) is useless in a streetable 390FE Galaxie. Production only ended because Holley purchased the rights to it's patented features, hoping to extend carb production longer into the emissions era with more efficient features. It worked to a point, as they used some 4100 features in other carbs to extend profitable carb production for OEM cars several years after production EFI was introduced. The choke assembly is the same as for the commonly available 2100 2V version:


Evolution of design - the Autolite 4100 was made by Holley with several more improvements as the Model 4010 and then retired. The latest version has yet more performance changes, and sports center-hung floats, easy to change secondary springs, and commonly available parts in 600 and 750 versions. There are even double-pumper versions. In-spite of being a very solid low-maintenance street/strip design, it sells less in hobby circles as some are not comfortable that it doesn't look like an old-school performance Holley or Edelbrock, yet uses features that are now standard in NASCAR and other high-end carb'ed applications:


USE WHAT YOU ARE COMFORTABLE WITH AND CAN TUNE EFFECTIVELY. :tup:
 

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I have a 390 in my '58 Ford and am very happy with my 625 cfm Carter AFB (similar to Edelbrock carbs). Since you mentioned gears, I have 3.70 gears in my car.

I had a 750 Holley (3310) on the car for a while and, by seat of the pants, I cannot tell any loss of horsepower using the 625 Carter as the car has good accelerataiton.
 

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Discussion Starter #14 (Edited)
I would like to thank you all for all the replies and info. A friend of mine came over today and brought a Holley 600 cfm with him and told me i could have it. I know it works because it came off of his Chevy II and i seen it run a month ago. It does need a rebuild so I ordered a Holley rebuild kit plus a power valve check ball kit. I was told I needed it to save on power valves plus it was only 10 dollars. I believe this carb originally came off a ford but not for sure. I hope it works when it gets the makeover. anyone have any exterior cleaning tips to make it look good again.
 

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Based on the D5TE on the choke horn it came off of a 75 or later Ford truck.
 

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Steer away from the Street Avenger series, I dont think they make a 600, but their 670s are miserable for a dead spot in the transition circuit, the standard 1850s dont have that problem
Just wondering. I hear this sort of banter and knocking of the Holley Street Avenger 670. I have one on a .030+ 390 and it runs just fine. Sure I had to tune it, but that is the case with all carbs. I had a 575cfm Demon, a 600cfm Holley, and the 670cfm Street Avenger, I liked the 670 best and sold the other two.
so my question:
did you actually have one of these carbs that you were unhappy with? or is this just internet legend that is getting spread based on one persons experience?
 

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Just wondering. I hear this sort of banter and knocking of the Holley Street Avenger 670. I have one on a .030+ 390 and it runs just fine. Sure I had to tune it, but that is the case with all carbs. I had a 575cfm Demon, a 600cfm Holley, and the 670cfm Street Avenger, I liked the 670 best and sold the other two.
so my question:
did you actually have one of these carbs that you were unhappy with? or is this just internet legend that is getting spread based on one persons experience?
Well, certainly a fair question

I have the experience of about 6 of them (counting early HP series that were the same) and I would easily call myself an advanced carb guy without feeling like I am being cocky or misleading. I also have done this for years professionally for other and personally with my own toys

The Street Avenger and Holley's first round of HP series used an Idle Fuel Restrictor circuit (IFR) that was above float level in the metering block, as opposed to the original design that is at the bottom of the block. Whats odd is that lots of aftermarket carbs do this too, but Holley only did it starting with the SA carbs and they seem to have the most trouble, I think its because the emulsion design adding to it (more later down the page)

What I have seen is, especially with winter fuel blends, these upper IFRs can off gas due to engine heat and make for a slow responding transition circuit (which causes a lean hesitation) and in real rare cases a fussy or unrepeatable idle, usually showing up hot, when you put a little load on it like a PS pump or A/C turning on. Worse, the issues aren't always repeatable and usually temperature related, so its nearly impossible to tune around it.

Matter of fact, I have found that by changing the front metering block to an earlier 1850 style with a low IFR, and drilling the proper IFR and PVCR restrictions, then jetting for application, they run fine. (Which they should at that point I changed all the effective metering and emulsion)

I have spent months drilling for removable bleeds and chasing IFR and bleed sizing when it is really their crappy metering design. Funny thing is 1850s and 3310s with the same date codes dont have that IFR or emulsion setup and dont have the issue

Admittedly, some guys will load up on accel pump shot with a bigger squirter or different cam, but thats like using a hatchet to cut a ham sandwich, the transition circuit should be responsive enough to vacuum not need a ton of pump shot at small throttle movement. FWIW I ran my 1000 hp with a .029 shooter when it was right, pump shot is a necessary evil, but it is not nearly as accurately metered as a vacuum driven/emulsified circuit.

In addition, as referenced earlier, a common issue is their main circuit emulsion holes that often need to be plugged and relocated. This compounds the transition circuit problem as the extra holes delay the booster reaction to airflow, again adding a ton of pump shot can mask it, but then you are just wasting fuel that the motor could pull in metered instead.

If yours runs well, awesome, but if I am building one for someone, I recommend against them and if they already own one, as soon as it has its signature lean tip in stumble, I swap metering blocks.

For someone buying a carb, it just isn't worth the gamble, there are better carbs.
 

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fascinating. Thanks for taking the time.
I have not had these problems, I also do not think we have any different 'winter fuel' but I could be wrong.

I've got a few extra 1850's metering blocks, I might mess around with them if I ever develop a problem, thanks for the idea.
At the moment the 670 runs perfect so I'm not gonna touch it :)
I doubt I'd have bought one brand new as there just seems to be too much bad press about them.

thanks again!
Drew
 
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