Carb Suggestions >>> Edelbrock / Holley / Quick Fuel / Demon / Other

[GoDadGo]

Hey Gang,

Please share your opinions about Carburetor choices for my MK-4 Roadster.

My engine is about to come back from my builder this Saturday and I was planning on buying an Edelbrock AVS 800.
The Engine Guru suggested a Quick Fuel 780 or Holley 770 with vacuum secondaries to keep things simple.
He stated that he likes the Holley style carbs since he's been playing with them for a tad over 50 years.
The engine should put out about 440-460 HP and about the same number for torque.

NOTE: Please don't cringe when you see what's going between the frame rails.

383 Small Block Chevy 9.7-1 Pump Gas Friendly Compression Ratio!
Engine Operation Range >>> 2,300 – 6,500 RPM.
Eagle Internally Balanced Rotating Assembly With 6" H-Beam Rods With Floating Forged Flat Tops.
Dart Iron Eagle 215 CC Heads with 2.05 Intake & 1.60 Exhaust Valves.
Weiand Team-G #7530 Single Plane Manifold.
Harland Sharp Roller Rockers & Other Go Fast Goodies.
Comp Cam Extreme Energy 284 Hydraulic Flat Tappet Cam.
Schoenfeld IMCA 1 5/8” Modified Headers / 3.0” Collector Into Traditional Factory Five Stainless Side Pipes.
New Old Stock Corvette ZF 6-Speed Transmission With Hydraulic Clutch. (.75 5th & .50 6th Gear Over Drives)
Moser TSD 500 / 3.73 Ratio / Eaton Style Sure Track Posi.

Please know that your opinions will be very much appreciated.

Steve >>> aka: GoDadGo

[Jeff Kleiner]

The general consensus is that these light cars do not respond well to Edelbrock carbs or vacuum secondaries. Although I've not built one with a Q.F. carb so can't give a personal recommendation it seems that most who have are satisfied.

Jeff

[GoDadGo]

Thanks Jeff! The Engine Guru (Mr. Boyd Breaux) has a wealth of knowledge and I've known him for a little over 30 years. He threw me for a bit loop when he changed his tune after he did the assembly. He stated the lack of weight, peppy set up, deep gears and the six speed trans were the mitigating factors for looking at a Holley style V/S style carb. Thanks Again!

[wallace18]

Make sure if you are putting in 10-15% ethanol gas to get a carb that can handle it. Eldo's do not like ethanol at all. That is why I am running ethanol free gas in my dual quad MK4.

[edwardb]

I've had both vacuum secondaries and double pumpers. No comparison. For these cars a double pumper is the way to go. I too was sold a vacuum secondary Holley for my first build because it would be "easy to set up." I didn't know enough at the time to question the advice. As it turned out, I never could get it to run all that well, and I wasn't alone. The double pumper woke the car up. X2 on Quick Fuel. Same style carb as Holley, but better quality and more adjustable. Highly recommended.

[bil1024]

Holley 4160 worked for me

[GoDadGo]

Thanks for the feedback for it is greatly appreciated.

The reason why I have been looking so hard it at the V/S style carb is simple, every other car I used them on all performed well. The issue is those cars all had automatic transmissions, some with bigger stall's than others; however, they all weighed between 1,200 to 1,700 pounds more than the MK-4 Roadster. The V/S carb just seems to do well on heavier vehicles, especially those with automatic transmissions. In addition, it looks like my engine size (383) is smack dab in the middle from a CID standpoint, when I look at the folks on the forum. Most push rod mills tend to be 302-331 range, while others pretty much take the Go-Big-Or-Go-Home approach with 406 & 427 CID power plants.

Anyway, I appreciate the replies!

[edwardb]

Thanks for the feedback for it is greatly appreciated.

The reason why I have been looking so hard it at the V/S style carb is simple, every other car I used them on all performed well. The issue is those cars all had automatic transmissions, some with bigger stall's than others; however, they all weighed between 1,200 to 1,700 pounds more than the MK-4 Roadster. The V/S carb just seems to do well on heavier vehicles, especially those with automatic transmissions. In addition, it looks like my engine size (383) is smack dab in the middle from a CID standpoint, when I look at the folks on the forum. Most push rod mills tend to be 302-331 range, while others pretty much take the Go-Big-Or-Go-Home approach with 406 & 427 CID power plants.

Anyway, I appreciate the replies!

You got it right. Automatic trans, heavy vehicle = vacuum secondaries. Manual trans, lightweight car, high power to weight = mechanical secondaries. Doesn't matter how easy the vacuum secondary is to adjust if none of the adjustments make it run well. Not so much on this forum, but there are multiple threads on the other forum about guys making the switch (including me) and mechanical secondaries are the overwhelming choice. Most cited bogging and inability to get the vacuum secondaries to come in properly. Exactly what I experienced.

[GoDadGo]

Question: Are most guys running Single Plane or Duel Plane manifolds. My ports are tall so my choices are really limited. Everything is set to play from 2,300 to 6,500 RPM, hence the Single Plane #7530 Weiand piece.

[Vman7]

Steve, have you considered the EFI style carbs?

FAST - http://www.fuelairspark.com/

FiTech - http://fitechefi.com/

Edelbrock - E-STREET® 2 EFI SYSTEM and PRO-FLO® 2 EFI SYSTEMS
http://www.edelbrock.com/automotive/mc/efi/

Holley
Terminator EFI https://www.holley.com/products/fuel...erminator_efi/
HP EFI https://www.holley.com/products/fuel...ection/hp_efi/
Sniper EFI https://www.holley.com/products/fuel...on/sniper_efi/

Quick Fuel Technology
http://www.quickfueltechnology.com/

David

[GoDadGo]

Steve, have you considered the EFI style carbs?

The goal of this build is to go totally old school. The only thing that I'm not going back to is an old point style distributor.

[Vman7]

lol.........you must have been posting when I was updating the link in post #11

Well since you are talking old school. I would go along with what Edward said, Double Pumpers. They are all have Mechanical Secondaries. Manual or electric choke. Dual quads
or single?

I like the SBC, I am more of a chevy guy when it comes to engines. Huge fan of the SBC "Mighty Mouse"

David

[GoDadGo]

lol.........you must have been posting when I was updating the link in post #11

Well since you are talking old school. I would go along with what Edward said, Double Pumpers. They are all have Mechanical Secondaries. Manual or electric choke. Dual quads
or single?

I like the SBC, I am more of a chevy guy when it comes to engines. Huge fan of the SBC "Mighty Mouse"

David

> Putting the Mighty Mouse in was a bit tougher than I had expected because the Corvette ZF-6 speed is so fat and the shifter is way back & on the left side and can't be moved.
> The good news is we were still able to scoot the engine a bit over to the left side of the car so my driveshaft goes straight back to the pinion flange.
> It also has lengthened my drive shaft so it will be between 11 & 13 inches so it improved the up and down U-Joint angles and limited yoke movement.
> I used the tins from the Ford Modular Motor for the drivers foot-well, which left me with 1.5" inches between the #5 header tube and the side of the foot box.
> Regarding the Carb, I'm Going Quick Fuel & Very Likely A Double Pumper Because Of All The Forum Feedback!

[Vman7]

> Putting the Mighty Mouse in was a bit tougher than I had expected because the Corvette ZF-6 speed is so fat and the shifter is way back & on the left side and can't be moved.
> The good news is we were still able to scoot the engine a bit over to the left side of the car so my driveshaft goes straight back to the pinion flange.
> It also has lengthened my drive shaft so it will be between 11 & 13 inches so it improved the up and down U-Joint angles and limited yoke movement.
> I used the tins from the Ford Modular Motor for the drivers foot-well, which left me with 1.5" inches between the #5 header tube and the side of the foot box.
> Regarding the Carb, I'm Going Quick Fuel & Very Likely A Double Pumper Because Of All The Forum Feedback!

Steve, wow that's a lot of work, just because of a transmission. Have to do what you have to do, to get things just the way you would like. Nature of the beast.

I don't know a whole lot about Quick Fuel carbs and EFI, but from the research I have done, it seems like a lot of people really like them. About the only carbs I know anything about is limited to way back, and I mean way back, like in the mid '70s to early '80s.....lol Mostly Holley and Carter AFBs. I have only played around with maybe 3-4 carbs. One was on my 70 RS Camaro, one on a 454 Chevy in a jet boat (750 holley double pumper) and a couple of others, I think one was my friends Carter AFB on his 71 RS Camaro. Other then that not a whole lot of knowledge in actually working with carbs. A lot of research over the years though.

David

[NAZ]

I'm also going old skool with my build using a SBC with 4150 style carb & Victor Jr manifold. I have a 385 (bored & stroked) SBC I'm stuffing in my hot rod and going with the double pumper. QF makes a 4150 style that is more adjustable than the stock Holley or you can use the QF metering blocks on a Holley to gain the benefit of the screw-in restrictors that allow you to tune the off-idle & mid-range A/F ratio almost linear. It does require knowledge of carbs to take advantage of the tuning capability of even the standard Holley & using a good A/F meter is a must to really dial in the A/F ratio. The light weight car doesn't need the V/S carb -- you'll be happy with a double pumper that's dialed in and not too big for the engine.

[GoDadGo]

Thanks for the post. Looks like I am going down the Quick Fuel Double Pumper Path!

If your are going a Small Block Chevy in a MK-4, then look at this website:

gpsconnection.com/photo.htm

Back in the day, long before I ordered my kit Dave Smith himself said to look at the engine placement on this site if I really wanted to go down this path.

The fellow is Randy Jones and I believe him to be one of the managing members of this forum. My engine is within 1/4" of his measurements. Even though his car is a MK-3, the measurements held true for the MK-4 as well. Just make sure you test fit and measure several times before you weld in your mounts.

Thanks Again!

[mcwho]

Sorry I'm late to this thread, I removed My Edelbrock and am so far very happy with the quick fuel ss 650 AN. I am still tuning and such but it is very tuneable. One thing to note is the QFT carb come with NO warranty. I have the Edelbrock for sale on Ebay.

[edwardb]

One thing to note is the QFT carb come with NO warranty.

From QFT's website: "Quick Fuel Technology warrants its new and remanufactured products to be free from defects in material and workmanship to the original purchaser only, for a period of 90 days from the date of purchase..."

There are a few exclusions, but the SS650AN isn't one of them. Granted, 90 days can go pretty quickly. But should be enough time to confirm there are no defects.

[TomH33]

Built a Dart SHP 400 CU IN SBC for my 33 and used EZ EFI. Worth every penny!

TomH33

[RoadRacer]

I'm a fan of mechanical - Holley 650dp for me.

But this is like Ford vs Chevy religious debate

[GoDadGo]

I actually purchased the AVS-800 a couple of months ago.
I stink at tuning Holley Style Carbs so I hope it works out.
I even say that in my last video:

https://youtu.be/_wnHDNgnNqs

[mcwho]

GoDadGo,

I agree with Jeff Kleiner 100%

I did put a Quick Fuel on my ford 331 and haven't been happier, I have the ss-650-an, which is a double pumper, annular.

I would think a 650 or 750 would be good for your use, also I used the Edelbrock RPM air Gap intake which is a dual plane, I think the single plane is more of a higher RPM racing unit,

my .02 cents

[GoDadGo]

GoDadGo,

I agree with Jeff Kleiner 100%

I did put a Quick Fuel on my ford 331 and haven't been happier, I have the ss-650-an, which is a double pumper, annular.

I would think a 650 or 750 would be good for your use, also I used the Edelbrock RPM air Gap intake which is a dual plane, I think the single plane is more of a higher RPM racing unit,

my .02 cents

Being a banker I will take those two cents.
The RPM range for everything in my engine is 2,300-6,500.
With that said it will be interesting to see how things turn out.
Finally, we expect to start it before June 1st, so we'll know rather soon.