luke89

im buying a new carb soon and am undecided between edelbrock or holley. i want decent fuel economy but i want power still. my engine is a 350 bored 40 over with an edelbrock intake, headers, summit cam now and wanna get a better one soon, and im going to upgrade the stock heads soon. i was looking at either the 670 cfm holley or the 750 cfm edelbrock. i dont know anything about carburators though and wanna know what some people think. what are some pros and cons of the different carbs? thanks everyone

IROCZ28KevinZ

iTrader: (2)

the 750 cfm edelbrock will be too big. 650 cfm would be a better fit. both companies make good carbs. the edelbrocks are really simple but don't give the extremely fine tuning abilities the holley does. i have an edelbrock on my car, and i like it. it was easier to rebuild and tune for me, because it was my first time messing with a carb.

ymenic

iTrader: (1)

chevyracingrox

I think you could make an Edelbrock 750 work but you'd be doing a lot more tuning and most likely re-jetting. depending on how much work you plan on doing to your heads the 750 cfm could very well be a better choice in the long run. the 750 will support more power and it seems like with your list of mods and your plans for the engine that you aren't going to just stop with a carb anyway.

duckmanquacker

For both fuel economy and power I prefer the Quadrajet. depending on the model you get either 750 or 800 cfm capability, small primaries for fuel economy and huge secondaries for power. best compromise carb all around.( and they are no more difficult to tune then the Holley or Edelbrock)

luke89

yeah. im not stopping after the carb thats why i was thinking the 750cfm

tater

iTrader: (10)

With a 350 all you need is a 600 cfm. I have run both Holley and Edelbrock carbs. Currently run an Edelbrock 1405 600 cfm. The 1406 (Electric choke) is set-up for more economy.

Search the classifieds on here. I have bought 2 Edelbrocks and one Holley real cheap.

In fact, the carb I am running, I bought for $30 shipped! Just took it apart and sprayed all of the passages out with two large cans of Carb cleaner, then put it back together. Works great.

87WS6

iTrader: (1)

Holley. My experiences with Edelbrock carbs has been less than stellar.

five7kid

iTrader: (14)

"T5" = stay away from Edelbrock and vacuum secondary Holley.

Can you get away with them? Yes. Would you be better off with a properly sized double pumper Holley? In my opinion, absolutely.

A 650 Holley double pumper would be fine. Even with future upgrades, you'll have to be making more power than your T5 can handle to justify anything bigger. The smaller CFM carb will improve driveability.

Yes, you will have to do some tuning. But, don't let that scare you away. If decent fuel economy is your primary goal, you'd have to do that with the Edelbrock as well, and you don't want a bigger carb. If peak power becomes your primary goal, then move up to a 750 - but you'd still be better served with a double pumper.

solid_snake2786

I just went through two... yes two Edelbrock carbs. They were 600 cfm with electric chokes. Out of the box one wouldn't idle right. I adjusted and adjusted, but couldn't seem to get it to idle. The second one I tore apart at the parts counter of my local auto parts store. Both floats were set wrong. One was even significantly higher than the other. To add insult to injury, a needle valve was bent. A brand new carb with a bent needle valve. Instead of shying away, I replaced the needle valve with a good one and installed it. I was amazed at how well it worked. A few tweeks and it was great, until this morning. It completely flooded out and was spraying gas out of the top like mad. Now I am stuck with an intake full of gas and pretty sure some fouled spark plugs. I say boo to Edelbrock. I'm trying a 600 Holley tomorrow. Hopefully I'll have better luck.

t-top havoc

iTrader: (3)

I've had both.
IMHO--
Holley is the way to go.

///DAN///

iTrader: (1)

holley's are for racing edelbrocks are for driving , just what I have heard over the years.

travis401

iTrader: (1)

Thats what you get from people who have no idea what they're talking about....

luke89

im thinking about just getting the 650cfm edelbrock thunder series or whatever. will this be big enough after i get good heads and a bigger cam? and how bad do you mean it is with the t5 because thats what i got but i dont wanna spend another 150 bucks on a double pumper if its not that bad?

rich5

Holley 650 would do u just right. Plus i think they look better than edelbrock but thats just me.

five7kid

iTrader: (14)

It'll be fine if you never open the secondaries.

luke89

what do you mean by that. they will never open?

chevyracingrox

meaning if you never hit the gas you won't hurt your transmission. I hear a lot about the T5 being weak on TGO. I never had any problems with mine, but I had a V6 so it's a different story.

duckmanquacker

2 different types of T5. the regular T5 and the T5WC, the latter is a stronger unit.

87WS6

iTrader: (1)

And while the World Class T5 is stronger than the stock T5, its still not a very strong transmission.

five7kid

iTrader: (14)

That's not what I said, is it.

I said, "...if you never open the secondaries." {emphasis added}

In other words, if you granny drive it and never press the accelerator far enough to open the secondaries.

ASE doc

I have had trouble with Edelbrock carbs. Almost brand new Ive had to replace leaking floats and make other various repairs. Holley makes a better carb. Just be sure to get one with the power valve protection kit installed or be prepared to install it. One good back fire without it will destroy your power valve(s). I like the Quadrajet myself and Holley does a nice reman QJ.

duckmanquacker

too true. But I'm not pushing anything over 385 hp and that motor is backed with a TH375B. My T5 is mated to a 2.8L.

luke89

im n ot worried about my tranny. i know there weak. i just wanna know if it really matters if i use a vacuum secondaries with a manual tranny in general.

Pablo

iTrader: (1)

This is basically the only post with legitimate information on this thread.

To piggyback on what five7 said, I have run an edelbrock 600 on a fairly stout 305. I was able to run 105 mph in the quarter with this carb which I felt was a pretty good mph considering I had a very cheap combo. The downside is that it is virtually impossible to properly tune the accelerator pump shot for a manual tranny and I suspect the same is true for heavy vehicles with a low stall torque converter. This makes for a really difficult launch and just driving in general. This is probably why I never got a 60' better than 2.1 with that car, and ran a 13.6 at 105. I should have been in the low 13s with that mph.
There is quite simply not enough pump shot volume nor number of squirters to adequately cover even moderately quick throttle openings. In my case this was on a light car (about 3000 lbs) with 3.89 gears. This is a better situation than most. The caveat to that is that I did have a single plane manifold.
Having tuned the carb with a wideband, pin drill set, various secondary air valve weights, squirters, jets, the whole 9 yards. I can safely say that I exploited every possible avenue in trying to band aid the lack of pump shot.

I even swapped back and forth to a custom TBI setup also tuned with wideband, the difference in transitory throttle response was staggering. The TBI was essentially like having an unlimited amount of pump shot.

I ultimately ended up purchasing a Holley 650 double pumper. When you analyze the specs of these carburetors you will see that it is really the best choice. As far as efficiency is concerned, you should get yourself a wideband and start tuning. I don't doubt that you could easily match the Edelbrock so long as you stay away from a lot of heavy throttle transitions that empty out the pump shot diaphragm.

At the end of the day though, the carburetor you get is only going to be as good as the person tuning it.

SLEEPER 86

"At the end of the day though, the carburetor you get is only going to be as good as the person tuning it."
very well put Pablo!

vortec350s10

I totally agree, I've ran a 1406 Edelbrock and now have a 650 Demon Vac Sec and I must say that tuning with a wideband is the best thing I've ever done. Next to the tach, it is the most important gauge to me when it comes to tuning. My Edelbrock ran well out of the box, the demon needed some fairly drastic tuning, but there are definitely advantages to Holleys (demons) as far as adjustability is concerned. Keep in mind whatever you get, it does not have to be a permanent thing. It doesn't take much to sell and buy a different carb if you are not happy with it.

RyanEricW

From my experience quadra jets without electronic feedback, and edelbrocks have both produced higher numbers on the dyno than carbs like the demon or holly.
Consistantly, I have seen quadra jets produce more power in most instances than edelbrocks, but edelbrocks have seemed to work better with a supercharger @ 5psi~.
I have not had very good experiences with demons, so if anyone has run them on the dyno compared to another carb on the same setup that information would probably be best suited here for everyones information.

mooch1

hi there, i went from automatic to 5 speed over the winter,,,since i started my car this spring the idle is terrible on my 1406 carb , ,,but idles bad ever since...,,it ran good in the spring when i first started the car the 1st time ,,but since then ,,the idle is all over the place...if i'm driving in gear and giving gas..no problems...but at idle it staggers and wants to shut off...goes from 500 rpm to 900 to 500 to 1100,,,,,then might even shut off...does my tranny swap have to do anything with it?.....thankyou.

ASE doc

Sounds alot like an unmetered air leak. Check your work. Did you leave any vacuum lines disconnected?

mooch1

besides the trans swap ...no other work has been done on the engine...the 1st time i started the car this spring it ran like last year ..it was ok...after the t5 swap it was ok... ..but since then, the 2nd time i started it , won't idle properly..all vacuums look fine ,,pcv valve seems to be ok ...

ASE doc

I appologize for my confusion. The same symptoms can be caused by too much air or too little fuel. It isnt likely an adjustment issue since nothings been changed. You may have pulled some debri into an idle air bleed. I would say to check or replace the fuel filter, but you say it drives fine down the road.

I guess I would start by turning each one of your idle mixture screws in until they stop, counting turns as you go. Then turn them back out to where they were, but now make them both the same. Then idle the engine and adjust both screws evenly until you achieve the best idle. If you cannot achieve good idle quality, then you need to look for either a vacuum leak or an idle circuit issue.

With engine idling, turn in one screw until it stops. The engine should stall or at least idle very poorly. Did the engine respond adequately? If not you have a clogged idle circuit. Bring that screw back out to where it was then repeat with the other screw. If either side doesnt respond adequately, you will need to clean the idle circuits. You can do this by removing the idle screw from each side and spraying carbcleaner into the open hole. Use a "straw" on the spray tip to direct the spray into the passage.

Next, using cardboard, make an air dam for the air horn of the carb. You want to roll the cardboard into a cylindrical shape that will seal around the airhorn and extend about six or eight inches above to block any foriegn material from being drawn into the carb during the following test.

Once the air dam is in place, use carburetor cleaner and carefully spray a small amount around the base of the carb, looking for any change in idle. If you notice a change, try to pinpoint the area where you find the most change. Thats most likely your vacuum leak. Be aware that any carbcleaner that gets into the top of the carb will cause a change in idle. Thats why you installed the air dam. Even the air dam may not prevent all intrusion so double and even triple check your work to be sure you dont falsely condenm a gasket. Also the throttle shaft bushings, even on a new carb, will allow some solvent to pass. So be sure to take that into account.

Also, if you have a painted manifold or if your engine is dressed up with any materials that may be solvent sensitive, think twice about performing this test, or use the "straw" for the tip so you can focus the spray more precisely. A smoke machine is another way to find vacuum leaks without using solvents.

I hope this helps, Doc

mooch1

thankyou for this...when engine idling ,,i really need to turn the idle screws almost all the way out,,it almosy seems they have no effect unlesss they are in too much.....if too srcewed in,,,the engine dies..i replaced the fuel filter because i thought i was that ,,,but i will spray some carb cleaner in the mix screws...i noticed i had this problem once the car stayed on 1/4 tank of gaz....maybe dirt got in somewhere,,,besides the idle mix screws...where else can i blow in some air to clean it out...thanks.

ASE doc

From your last message it really sounds like a vacuum leak. Your idle circuits seem to be working normally. Clearing out the idle circuits still wont hurt. Unless you have other drivability issues, I wouldn't do too much else. A can of Seafoam, or any other quality fuel additive, in the fuel tank might be good though. Good luck

mooch1

ok,,,but the idle mix screws look like they aren't doing much ..unless screwed in all the way or almost in ,,,is this normal??... off...i will clean the idle screws passage and put in a can of cleaner in the tank...and try that test ,,,what else you think?...thankyou.

ASE doc

Sorry again, guess I misunderstood your message. Idle circuits may be a problem. The cleaning should help. Unfortunately, aside from atleast removing the air horn, theres not much else I can offer. Our conversation should attract some other members. They might have more insight to offer.

mooch1

ok...i appreciate your hrlp..one last thing..the idle cicuits are the idle mix screws?..

ASE doc

The idle mix screws are the easiest access to the idle circuits. Actually there are also idle air bleeds inside the air horn, on the top of the carb. I dont have the edelbrock carb in front of me right now so I cant say which opennings they are. It wont hurt though to hit all the exposed ports inside the air horn with a shot of carbcleaner. That and spraying into the idle screw holes should clear out the circuits pretty well.

ASE doc

The Edelbrock 1406 is a repop of the Carter AFB Competition series. HP Books put out a great little book on Carter carbs. Im sure Amazon has this book. Its a good read and excellent info for anyone running and/or repairing the Edelbrock 1406.

mooch1

ok,,i will try all that,,,cleaning the idle circuits with air and carb cleaner ....it's funny how this carb ran like a charm for almost 2 years...i literarly bolted it on out of the box and that's it ,.,,ran great and was and still is very responsive at higher acceleration....but now this idle issue bugs me because i don't want to stall at a red light or constanly give gas to keep the engine from shutting off....do you think i should of or forgot to do something when i switched from auto to manual?,,,thankyou.

ASE doc

The trans swap might make you want to play with secondary boosters for quicker response, but shouldnt affect idle.

The key point here is that it ran great after the swap, until you ran it low on fuel. Fuel filter should have kept any crud out of the carb but its possible something got through.

Also, do you have a filter before the pump? Its a good idea to keep crud out of the pump.

I hope that more members respond on this issue. I have some experience with the Edelbrock/Carter carb but others may have more to add.

A note to anyone viewing this thread. The HP Carter carb book that I mentioned above applies to all 1400 series Edelbrock carbs. Edelbrock has made minor changes to the design but its still basically the same carb.

Im not faniliar with Edelbrock's new AVS model but Im sure the HP book would still be useful.

Also, for anyone looking at the Q-jet. Edelbrock did make a Q-jet version, Ive seen a few of them, Edelbrock"s 1900 series. Ive mentioned before that I have concerns about Edelbrock's quality. Ive wished a few times that Vic Jr would have done like his dad and stayed with manifolds. (I hate to say this because I still run a few of his parts on my IROC Z.)
My own issues aside, Edelbrock's Q-jet would be one way to get a new Q-jet and, while I didn't see on their website where they still offer the 1900 carbs, they do still offer parts for them.

mooch1

hi , my fuel filter is after the pump right before the carb ,,,,it's a see through type...gas looks clean ,,but maybe some dirt got in when i was really low on gas...

luke89

hey i just picked up a set of vortec heads and a edelbrock performer rpm cam and lifter set. and like i mentioned before my engine is bored 40 over with flat top pistons. what carb would get me the most horspower and still good fuel economy. im possibly switching to auto since idk how much longer my t5 will last. thanks

88TransAmGuy

iTrader: (3)

I have a Carburetor in my garage?

The Project

iTrader: (6)

Sound advise.

mooch1

hi , i bought some carb cleaner , one for the gas tank and one spray can , put in some fresh super gas and cleaned the crap right out of it,,, my edelbrock runs like a charm again...i will never stay low on gas again...

RedneckNo4

I prefer the adjustability of a holley double pumper ( i have a 650 DP with an adjustable primary AND secondary metering block and a wide band hooked up) I have a 3500rpm stall converter and a 4:10 rear in my S10, (weighs ~2800lbs) it needed the dp the vac secondary carb I had on it never drove the way i wanted it to

though I love the concept of a Q-jet, I'll probably drop one on when i build a 302 for my trans am

(for some reason this came up on another thread when i'd posted it on this one?)

Big Cleatus

My 350 is bored .060" with flat top pistons. I have a Comp Cam and roller rockers. My engine puts out 375hp, and I use just a little old Holley street avenger 650cfm. In my opinion though, the best carb to get for best fuel economy and most hp, would be a Rochester Q-jet. Dang good carbs. If you rebuild one there are some little tricks to it to boost power as well. I got a book on how to rebuild and boost Qjets from Barnes and Noble for like $20.