4-barrel recommendations

[badandy73]

Ditching the sniper on a blueprint 306 and looking for a dependable carb setup. 95% street driven, save for a few trips to the woods and heading over to the beach once a summer. Not doing any rock crawling, but don't want it to be worthless off the pavement either. Planning on using the dual plane intake that came on the engine and would be a bonus to be able to run the stock kickdown rod with the C4.

Punching the numbers into the Holley carb selector gives me options ranging from their basic replacement carb to the street avenger, 570-650 cfm. The street avenger (4150) seems to fit the bill and has the ford kickdown setup, leaning towards the 570 vs. 670, with the 'less is more' principle. Will I be leaving anything on the table going with the smaller size, or should I step it up to something in the 650-670 range?

Have heard the Edelbrocks are fairly foolproof, just not familiar with their lineup to know where to start. Any other brands or recommendations I should be considering?

 

[blubuckaroo]

Here's a good carb CFM calculator.

https://www.summitracing.com/newsandevents/calcsandtools/cfm-calculator

 

[ared77]

Soooo many people go for the "bigger is better" on carbs. Truth is the smaller one will probably work better for you.

 

[cannunz546]

I just installed the Edelbrock AVS 2 on my built 302 (it has about 470 HP). I chose the 650CFM. It's the best performing carb I've ever run. My engine only has about 1500 miles on it but the former carb never had proper mid-range power or performance. The AVS 2 has solved that problem and more.

 

[Vincen]

I have run a 570 street avenger and sitched to a 500 cfm elbrock AVS. Believe or not, the 500 cfm carb is much snappier and more efficient.

 

[Glass Pony]

I run a 600 cfm Holley on my 351W. Runs good, starts good, and passes emissions every time.

 

[rguest3]

Why are you getting rid of the Sniper?

 

[SteveL]

After running an edelbrock and a holley I swapped to a q-jet. I've had far better luck with the q-jet on and off road

 

[blubuckaroo]

After running an edelbrock and a holley I swapped to a q-jet. I've had far better luck with the q-jet on and off road

I'd be using a Quadrajet too, but getting it to fit with a 302 is a problem. I couldn't find a spread bore intake for a 302 and I didn't have room to use the adapter.

 

[SteveL]

I'd be using a Quadrajet too, but getting it to fit with a 302 is a problem. I couldn't find a spread bore intake for a 302 and I didn't have room to use the adapter.

I run em on my 351w's with an offenhauser intake. I think the model is a 360. I believe it's also availablefor the 302. It comes with both bolt patterns but you need to bore it out to fit the butterflies of the q-jet. Pretty easy job. I just laid down and traced the q-jet gasket. Then ported out the manifold to match.

 

[badandy73]

I just installed the Edelbrock AVS 2 on my built 302 (it has about 470 HP). I chose the 650CFM. It's the best performing carb I've ever run. My engine only has about 1500 miles on it but the former carb never had proper mid-range power or performance. The AVS 2 has solved that problem and more.

I have run a 570 street avenger and sitched to a 500 cfm elbrock AVS. Believe or not, the 500 cfm carb is much snappier and more efficient.

Looking at Edelbrock's website, the AVS2 did look good, especially with their claims about better reliability off-road. Are you guys running them with a manual or automatic, if the latter how does it work with a kickdown setup?

 

[badandy73]

Why are you getting rid of the Sniper?

It's a long story and could be it's own thread, but in a nutshell just can't get it run consistently. Been fighting it since last summer when I first installed the engine. Have gone around and around with the holley techs. Last straw was shielding the coil wires, triple checking the wiring and doing everything I could to mitigate RF interference, only to have them then tell me that the ECU might be bad and that it would need be sent in to be tested. Will say that they did offer to replace it, however don't have any in inventory currently to send out. This is the second unit I've had in that time, first was replaced no questions asked from other issues. Tried everything and then some to get it work all the time and can't even drive it around the block without it running like dog crap. Just can't trust that it won't leave me stranded somewhere and done fighting it. End rant.

 

[BoltBuster]

Whats making you drop the Sniper efi?

Ive used Holleys for years.with differnt vehicles.They can have their moments like any carb, espically during different temperatures or bad fuel. I currently run a 670 Truck avenger. Its bascally the same as a street carb except for the dual float springs to prevent the float bounce and the crossover vent tube that prevents fuel dump into the bowls.. Which is a great design for a Bronco or Truck..

The Demon is a great carb for street and very good design.Not sure of their current setups or cfm avalibility. About 10years ago they offered a float kit to match the Holley Truck Avenger minus the cross over tube. Which is easy to duplicate. All of that may have changed now and is possibly sold as a truck or offroad carb.

Ive never used a Elderbrock carb, which is basically a Carter/Quadrajet.They have alaways seem to be a decent carbs but are in the basic of basic.

The Predator was the top of the line carb for any performance vehicle.Im not sure if the still exist on the market.Super expensive back in the day. EFI has changed all aspects of a vehicle today which its like comaring apples to ornages.

 

[okie4570]

I'll recommend a a quadrajet over a edlebrock or a Holly any day. Been running a qjet trouble free for almost 10y now, mild to wild street and rocks.

 

[jckkys]

The best 4bbl carb for a 302 is the Autolite 4100 480 CFM. A quality rebuilt version is expensive and DIY requires some carburetor knowledge. A 450--500 CFM version of any carb fits you're needs. The idea of leaving anything on the table is BS. It only applies to full throttle high RPM operation. That's something I do only occasionally and small carbs loose very little if anything. NASCAR racers with 700 HP are restricted to 390 CFM carbs. When I was 15 and ignorant I put a 780 CFM Holley on a 390FE and it never ran nearly as well as the 480 CFM 4100 that went back on the engine. The Holley List #4548 is a great choice for a Holley. It's 450 CFM and made for Fords so it runs great with no changes. Holleys need to be rebuilt every couple years or the gaskets start to leak. Carter AFBs and AVSs are low maintenance and easy to tune but not great on inclines. The linkage for both throttle and kick down can be a pain cause they're so wide. The Summit racing 08500 is almost as good as the Autolite 4100. It's 500 CFM, don't leak, and and are very tunable. QJets are Chevy carbs that are hard to mount, tune, and find a linkage for. Do some searches on each and see what others have experienced.

 

[ngsd]

Sorry to hear that it did not work for you. I did the Blueprint 306 with Sniper and it was plug and play out of the box. I guess you may may a dud but I am really happy with mine much more so that the Holley 4b I have on my other one.

 

[BroncoJimbo]

Holley Truck Avenger here. Just a 470 on a built 351W and it works great. It ran well out of the box but even better once I started the tuning process. Holley provides good support too. I considered the Q jet but I didn't like the funky adapter set-up.

 

[phred]

Call Jet Performance and give them you engine specs. They will build a carb specific for you needs. I’ve been running JP quadrajet for 12 years and have never touched it.

 

[SteveL]

Call Jet Performance and give them you engine specs. They will build a carb specific for you needs. I’ve been running JP quadrajet for 12 years and have never touched it.

^^^^^^^both mine are from jet performance. Comes pretty much ready to go.

 

[gnpenning]

If not the 4100 then qjet. A very simple carb to setup and very dependable. Millions made and successfully used in a wide variety of applications, including what you described.