5.2 Magnum CFM Help

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64drtGt

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I'm starting to gather parts for my 5.2 magnum swap with a Airgap/M1 knockoff intake and headers with a cam in the future and was wondering what the best CFM carb would be. Its going into a 84 D150 pickup with a 4 speed OD and 3.23 or 3.55 gears.
 
I am building a similar truck and plan to run an 800 Thermoquad. The 318 will suck every bit of it right down.
 
for everyday driving, an edelbrock 600 carb would work fine...they even have electric chokes....
 
yeah truck is gonna be my DD but I will prolly take it to street fights on friday nights for a little fun lol.
 
that is a holley 4010 series that summit sells under their name..
 
For daily driver duty, I would stay smaller side 600 CFM range. You might give a few top end horsepower, but smaller will give a better vacuum signal to boosters, for better off idle performance, which is where much of around town and daily driver are used.

I would steer clear of the Summit brand carb. It is rebadged, for Scummit. If it was a great carb in the first place, why would it have gone away. The only reason it is back is so Scummit can put their name on it, private label, for more profits.

PS, no, I don't like Scummit or Jugs. They are the death of the local speed shop, in my opinion.
 
Backtobasics said:
For daily driver duty, I would stay smaller side 600 CFM range. You might give a few top end horsepower, but smaller will give a better vacuum signal to boosters, for better off idle performance, which is where much of around town and daily driver are used.

I would steer clear of the Summit brand carb. It is rebadged, for Scummit. If it was a great carb in the first place, why would it have gone away. The only reason it is back is so Scummit can put their name on it, private label, for more profits.

PS, no, I don't like Scummit or Jugs. They are the death of the local speed shop, in my opinion.
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Where I am from there are no " speed shops" I suppose the closest thing to that is either a guy that does machine work for engines or Alan Johnson's Pro stock Garage.

70aarcuda said:
that is a holley 4010 series that summit sells under their name..
Click to expand...
Is that a bad thing? I have heard good things about the summit carb.
 
so far everyone I have met that bought the summit carb has had nothing but issues.

Most recent was a 750cfm version that he bought ALL of the tuning parts to get it adjusted right including using an O2 sensor to get his AF correct. no matter what this thing didn't work.

He took everything back and bought an edelbrock avs 800cfm.. bolted it up.. everything was almost spot on, couple little tweaks and it worked great.

Not a fan of the 4010 design summit carb.
 
On a tight budget lol I may just wait till I'm almost ready for a carb find me a used holley or eddy and rebuild it if needed.
 
I bought the Summit carb, and it idles well, but I have some other issues not fuel related that are keeping me from any progress. After reading that little review, I might have to take another peek at the idle mixture screws.

If it was a great carb in the first place, why would it have gone away.
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I'm pretty sure when the original Holley 4010 came out, it was still greatly overshadowed by the easier to mess with original 600 and 750cfm vac sec and DP carbs. You have to take apart the top half of the carb to change out the squirters, and that's a bit of a pain compared to just pulling off one screw and making sure the gasket was good. And you could do bowl off mx on a three piece Holley in a matter of minutes...people were used to that design and had been for decades-why change over? Not to mention, the aftermarket was so ridiculously huge for the other standard Holley carbs, and offerings from QuickFuel, Carb Shops, and the like, the 4010 never stood a chance.

I'm not trying to defend the 4010, nor the Summit carb as I have yet to really wring it out. I might find out it's a steaming pile of poop and wanna get rid of it later, but for right now, I figured I'd give it a chance. IF that's how it turns out, I still have a 600 Edelbrock in my garage I can use in a pinch. I'll just have to deal with the loose throttle bushings giving me grief.
 
I put a 650 double pumper on mine (5.9) and it runs very good. I'd much prefer the TQ, but there's no hood-clearance with an adapter.
 
The Summit racing carb is not a re-badge unit from Holley, Holley simply stopped selling them. Super low volume in there attempt to have a 2 piece design like the Carter/Edelbrock carb.
There is one mod to it that I can see and that is the fuel entrance angle has been moved from level out to slightly downward.

IMO, for your 5.2/318, there are 2 styles of carb to choose from, Holley and Carter/Edelbrock. If you choose the Holley, use a 4150 , 600DP. The manual trans rides like a DP over a vacuum secondary.
Here is a 600, must add electric choke to this one, if desired of course)
http://www.summitracing.com/parts/HLY-0-4776C/


IF you choose the Edelbrock, IMO, I do think very much you will like the AVS style (Thunder) carb better over a AFB. The secondary air door is tuneable and helps for a smooth transition into the secondaries.
Choose the 650 AVS carb.
http://www.summitracing.com/parts/EDL-1806/
$10 more but includes electric choke.

The TQ is a nice carb if you can find one that is right and has the small primaries. The smaller 1-3/8 primary size will have that 318 running crisp. Find one that is from the early 70's or a truck carb, late 70's max. Less vacuum lines on the carb the better. Use AFB rods to tune, bend them @ 3/4 of an inch to fit. (It's real EZ to do.)
 
Alright I'm prolly just gonna try to find a used 650 eddy AVS I cant afford a new one I dont think.
 
Rebuilding is easy, it just requires a bucket to fill 3/4 of the wqay with carb cleaner so you can dunk, in full, the carb, running water to wash, compressed air to blow the passages clear and clean, not to mention, dry. Gasket scraper, 3/8 drill bit (To set float) and a few drivers and pliers.

If there is no major parts needed, then a gasket kit is cheap;
http://www.summitracing.com/parts/EDL-1472/
 
rumblefish360 said:
Rebuilding is easy, it just requires a bucket to fill 3/4 of the wqay with carb cleaner so you can dunk, in full, the carb, running water to wash, compressed air to blow the passages clear and clean, not to mention, dry. Gasket scraper, 3/8 drill bit (To set float) and a few drivers and pliers.

If there is no major parts needed, then a gasket kit is cheap;
http://www.summitracing.com/parts/EDL-1472/
Click to expand...


Alright doent sound bad I'm one of those type people that can do anything with a good instruction so I dont think it will be to bad I'll wait and find me a carb once I get back home next month unless I see a good deal on ebay sooner.
 
Well I thought about it some more and after talking to a few people on chat and some other places I have changed my mind again.... I was going to run a 650 AVS series but I now am planning on a 600 quick fuel slayer carb.
 
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