Hello Everyone,
I'm a long time reader of the 80-86 F-Series forum and believe me I have learned a ton reading through everyone's experiences so I have to thank everyone for that. I'd like to get some advice.

I have an 86 f250 351w C6 4x4 in need of a carb. I pulled the original 4180 off to rebuild and the carb base is cracked so it's shot. The previous owner disabled the smog system by removing the belt and other misc parts. Emissions is not an issue in Maryland. Should I get a rebuilt 4180 leaving the EGR/smog equip as is or should I go with an aftermarket replacement and ditch all the smog stuff since it's not really doing anything? If aftermarket what do you recommend?

Prior to yanking the carb the truck ran pretty good even with the smog pump belt off. It was a little cold weather cranky with a cough at the carb if it wasn't fully warmed up so that's what prompted me to rebuild after going through the necessary carb adjustments.

Any feedback is appreciated. Thanks!

 

You could use a 4160 600 cfm Holley.The intake manifold will accept that carb,but there should be a EGR slot that will have to be plugged.On my '85 I just used a steel adapter plate with carb gaskets on either side.The slot is on the carb pad.The other intake in the pic is a Edelbrock Perfomer.

 

Thanks for the reply. So you'd ditch all the smog equip and block off the egr?

 

Opinions will vary on this, but its probable doing more harm then good if the entire smog system isnt in tune and working correctly.

 

OP I converted my set up to propane with a Holley four barrel baseplate for the mixer.As a point of reference,I run a carbed 460 without EGR or smog pump in a 1988 F250 and it runs great.I had 351W in a '83 e150 van 4x4 with Edelbrock heads,aluminum intake,493 lift cam,and headers without egr or smog pump or cats and it passed emissions in my jurisdiction.I did use a OEM 2 barrel carb to get it through though as the Holley Street avenger carb was plagued with problems.If the emissions system is working properly,then leave it be.Otherwise,I say do what you need to do.

 

My vote is for an Edelbrock 1406 if you want economy and 1405 if you want power. The reason I say that is I bought an 81 w/a built 351M and a Holley 4160 with stock jetting. I got about 12.5 MPG with it on the highway but it didn't have a crisp part-throttle response and kind of blubbered at lower speeds. I had the 1406 sitting on the shelf, with stock jetting, and put it on. With no other changes the blubbering went away and the part throttle response was very crisp. But maybe the best was that the MPG went to 14.25. However, I don't think the full-throttle acceleration was quite as good as with the Holley.

But, I will have to tell you that I dislike Holleys, and even if the MPG had been the same I would have run the E'brock. I've seen so many Holleys with blown power valves, split accelerator pumps, warped bodies, and leaking gaskets that I want none of them.

 

I have noticed improved mpg and power when running a Holley, and if you do any sort of offroading then that would be the way to go. That being said, I now run an edelbrock on my dd, mainly due to the fact that tuning the Eddie is much simpler and it requires much less attention then my old Holley. Both are great carbs that will need to be tuned out of the box, the Holley will just need it done more often and require more time to do it.

 

If properly tuned and set up properly,Holley carbs can be very reliable.Holley carbs a very simple design if you understand them.The biggest mistake people make when tuning or adjusting is that they either make too many adjustments at once or they stray too far from factory settings.In over 30 years of working on cars/trucks,I've dealt with Holley Q-jet and Carter four barrel carbs.Eddy's look like a derivative of the Carter AFB.I've seen many different carbs leak fuel and it generally was due to improper assembly or reusing worn or torn gaskets or improper tightening of screws.The only major problem I've had with a Holley is with a Street Avenger that has the plated finish.The plating peeled off inside the primary metering block/bowl and caused stumbling/sputtering/backfiring etc...I've used the classic greenish Holleys without ever seeing a similar issue.I've never run a Eddy but would try one in a stock type engine although none of my engines remain stock for long.

 

Edelbrock bought the rights to the Carter Aluminum Four Barrel (AFB) and the Air Valve Secondary (AVS) carbs. The Performer carbs are the AFB while the Thunder carbs are the AVS. These carbs use metal to retain the gasoline and don't leak. They use an accelerator pump that lifts the fuel, so even if it somehow fails it doesn't leak fuel. And, the power enrichment circuit is done via metering rods that - guess what - can't leak.

On the other hand, Holleys use gaskets to hold the fuel in. They have a diaphragm accelerator pump that is known to leak - both inside the carb into the engine as well as outside. And, they have a power valve that is known to - guess what - leak. Yes, later versions of their carbs have fixes for some of those faults, but there are billions of them running around, many owned by members of FTE, that don't have the fixes for design flaws. We see a bunch of guys having those problems with the Holley, and for that matter also the Autolite/Motorcraft carbs which share the Holley design.

At 65 I guess I could say I've been working on cars for at least 50 years. I grew up with Carter and Rochester carbs, both of which shared very similar designs. My first Holley was on my brand new 1969 Super Bee and it was an unmitigated piece of junk. The body was warped from Day One so it leaked at the cork bowl gaskets. The slightest hiccup and it backfired and the power valve was gone. Hence my "love" for Holleys started in May of 1969. Oddly enough, had I known the bulk of the Super Bees got the AVS from the factory I could have solved the problem quite easily and simply.

I'm not saying that Holleys don't work, but that they have design flaws that have caused many, MANY people to have trouble with them. At the same time there are carbs out there that don't have these flaws, so unless you need the absolute max power output that the Holley is also known for, why opt for a trouble-prone design?

 

Holley's were the thing to have back in the days when people were trying to squeeze that last half-a-horse out of their motors.

The Carter/Edelbrock design works just as well as the Holley's if you set them up to run and get the most power that you can. But, like many people who use Edelbrock have found, they are prone to less problems than Holley's, and they're pretty darn close out of the box for stock performance/gas mileage.

 

Good point. The Holley 4160 was "out of the box" and got 12.5 MPG and blubbered. The E'brock 1406 is "out of the box" and gets 14.25 MPG and has a much more crisp part-throttle response.

 

Both excellent / informative posts.

I have dealt with both Holley and Edelbrock carbs. My favorite is the Edelbrock for most of the reasons stated. A correctly tuned Edelbrock will run just as good as most any Holley.

 

Sounds like the consensus is to ditch the 4180 and go with a 4160 or Edl 1406, possibly leaning more towards the 1406. I was able to tune the 4180 pretty well, the 1406 will be new territory. Not sure if it's worth getting a belt on the a.i.r. pumps and dealing with all the misc vacuum controls for that. Seems like without the a.i.r. system running the 4180 was running rich and with the 4160 or 1406 I'd be able to lean it out. Thanks for all the info everyone!

 

Welcome. The Eddy 1406 comes jetted leaner than the 1405, which is the performance carb in that line. IMHO the 1406 comes just about right for a 351 cube engine and is dead simple to tune as you loosen a screw on the top of the carb, swivel a little tab out of the way, and the metering rod pops up to great you. Swap that out, both of them actually, and you are "tuned" - or at least you've made the change you planned. No need to pull the carb or spill gas all over the engine.

 

I'll be the last to defend Holley as I still have a bitter taste from a crappy Street Avenger that caused me lots of headaches.That being said,I'm sure there have been many issues with Holley carbs,just as there are issues with other manufacturers carbs.The reality is that you can retrofit a older Holley carb with non stick reusable gaskets,power valve blow out kits etc...I like my older Holleys because thats what I've used and I know how to tune them.Once tuned for a performance application they don't get out of tune.Jets,shooters,pump cams don't change by themseves.I've never had a secondary vacuum diaphragm rupture,but have had a accelerator diaphragm leak.I've also had accelerator diaphragm leaks on OEM carbs.I see that there is alot of dislke towards Holley carbs,but there are millions of them in use.I don't understand Eddy carbs but would try one(on a stock engine) if I found one cheap enough.I once had a Carter AFB(closest to a Eddy) on a 440 powered '73 Duster.I swapped it for a holley and never looked back.I guess I haven't had nearly as many problems with Holley's as some people have had.Since I have lots of spare parts,cores and know how,I'll stick with what I know.