I have stall/fuel float issues with my edelbrock. I will get more horsepower out of a holley anyway. Should I swap it?
This is for the 84' L69.

 

This was just asked.

https://www.thirdgen.org/techbb2/sho...hreadid=164944

 

Jester are you SERIOUS about a real 20-30 hp gain on a "mild" motor???

Let's just take the setup in my 84' for example. I expect it put out a respectable 275-285 horsepower....with the edelbrock I guess. A holley/Demon will give me that much more power?

 

How about try cleaning out the needle & seats and reset the float levels?

Pretty much the same thing you'd have to do if you had the same problem with a Holley carb.

 

Carb is almost brand new and un-molested... 6 months old.

I was thinking of lowering the float level as the car only stalls on inclines in either direction. I don't really understand where you are supposed to bend the tabs when you adjust the floats though...or how much I should adjust them.

 

replace the fuel filter. clean the regulator and carb needel and seat. Lower the fuel pressure to 5 psi.

Edelbrocks like Qjets don't like (or need) a lot of fuel pressure.

Pull the manifold and block off the exhaust heat raiser.
( manifold gasket)
The manifold plenum is getting too hot.

Get a wooden divided carb spacer.
This wil reduce the temp of the carb and reduce fuel perculation.
A common issue on Edelbrock carbs in warm weather.
This is most likely the sourse of the stalling/ flooding.

A holley 600 cfm carb will not make any more power than a edelbrock 600cfm carb. Both need to be fine tuned for max performance, but 600 cfm is 600cfm.

 

Fuel filter is new.
Fuel pressure IS set at 5 psi.
Spacer will not fit under the hood.
Manifold heat riser...
edit: manifold heat riser....I have an open element air cleaner. So it is dissconnected.

 

A 1/2" wooden carb spacer will easily fit between a Performer intake and carb with the *Right* drop base aircleaner

Remove the intake manifold and block off the exhaust passage
to the manifold Plenum under the carb.
This is a common problem with The Performer manifold.
It gets too hot unless you block or restrict the flow of exhaust
gas under the plenum.

The best and lowest air cleaner base is the one from the late 60's and early 70 camaro and corvette.

Here's a pic. You need a 3/8" plastic ring spacer for an Edelbrock carb with this. Edelbrock accessory part.

minor trimming at the back for an HEI.

 

The generic aftermarket air cleaner base does not sit near
as low as the old GM design

this is a pic with the RPM intake which is quite a bit higher.
There is still enough room for a NOS plate here.

 

...

 

.. and the GM base

 

That would be what we would call in technical terms, BS. Why don't ya just stick a 600cfm straight pipe on it and run the pump right down the bore..after all it'll make the same power. Umm....no.

Yes, they are worth that much gain, give or take depending on your motor of course. I've seen it dyno proven a few times. In the range you're talking about 30 is probably pretty lofty....I'd say it's probably closer to 18-20.

 

Jester: I know you hate all Edelbrock products But to mislead
some one like that is not serving them, or this board.
Sure you can run a holley on the dyno and switch to and Edelbrock or another brand and see a difference in power.
Especially out of the box with no adjustments.
But once both are fine tuned for correct Max power AFR, they will be real close in power output. Like around 5 hp on this motor.
Well within the testing tolerance variation of any group of dyno
tests.

When properly tuned, a holley 600,Edelbrock 600 A Demon 600
or a Carter 600 will all be real close in power.
Even an old Qjet will do.
You , or anyone else that keeps an open mind and doesn't mind tuning their combination can get great performance out of ANY of these carbs.
Most people have no big problems with Edelbrock Carbs
and are happy with them.
I've run mine back to back against my holley on the same car and they run so close it isn't funny. The Edelbrock actually runs slightly faster. I've compared my holley back to back against other good holleys and it's a good one. Still got it too.
A few friends who've switched from a Holley to a Edelbrock
had nothing but good to say about them. Very smooth carb and easy to work on.
One of the best $200 bucks spent on the car. Bought it used
and bolted it on and didn't even need to adjust the mixture screws. Can't complain about that too much.
Ran great with the out of the box jetting, ran a little nicer after a rod change. pretty easy.
All carbs need proper fine tuning, can get fouled up with dirt and
need a rebuild once in a while.

 

Jester's correct he even has Dyno proff floating in old threads. Anywho I just swaped my 600CFM chrome holley (silver lol) for a 625 brand spanking new AFB today, spent all after noon tuning it. I lost 200rpm over the Holley which isnt too bad consideing the Edlebrock 600 1406 that I had on there before was chocking off 400rpm compared to the stock holley. So break down of properly tunned carbs, 600 CFM Holley 6400rpm, Carter AFB 625 CFM 6200 RPM, Edlebrock 1406 600CFM 6000 RPM. A/F moniter is right in the middle were it should be so they all were tunned properly. How much HP would you guess 400rpm is?

 

You're over reving the motor first of all.
(valve float) 6000+ rpm is too high for that cam. Second if your holley is so good why are you changing carbs like underwear?

the AFR guage should read rich @ WOT (13.5:1 to 12.3:1)
not in the middle which is 14.7:1 Chemically correct.
By the way 14.7:1 is not the best AFR for cruising either.
You'll get better mileage with it tuned a little leaner.
Plugs will last longer too.
Under what conditions are you basing this RPM comparison?

WOT running down the road? in high gear?
Or reving to to the moon in first gear? Or some thing.
Not very scientific.
Sorry, I do my test and tuning at the track or with a vericom
or on a dyno.
At any rate you're testing the motor way beyond its range and beyond peak hp rpm.
If you're having that much trouble tunng in a new carb something else probabily is wrong.

Any of these *&^*% up carbs ya can't tune in, just box 'em up and send 'em up to me. I'll be glad to take 'em off your hands.
Would love to do a Custom dual quad project and need someones castoff "JunK". Hhe hehe hee. Like a couple AFB 600's.

 

Misleading is saying that all inductions are equal, they aren't. They all function differently, with differing degrees of success. If gross cfm was all that mattered everyone would just stay with thier Q jets. They're rated at more cfm than 95% of the Holleys and Edelcraps both that we here are using, but they ain't exactly dyno kings.

It's not misleading because there is proof out there, and plenty of it. I've posted it up here before. Tests done AFTER fine tuning on all the contenders before you go on saying they just needed to be tuned.

If you wanna recommend Edelbrocks for whatever good points you've found in them go right ahead. Just do try to keep it to reality

 

I think I'm going to get a holley cause I'll always need another carb in the future!

Which one should I get? 600cfm.
I hear that the side hung floats are not as good as the center hung ones....or does it not matter on my setup? I have a 625cfm center hung Road Demon ( not the new crappy ones) on my 91' and it's pretty darn nice. This time though, I'm gonna go the cheap route and I can't shell out another 340$ for a Demon.

 

Nope 6500RPM is just dandy for my setup since the cam was BS rated 1500-6000RPM 1.6 RR make it fine till 6500 and I dont have stock springs either.

The reason I changed carbs is for fuel economy, AFB's/Edl/Qjets all have a better metering system which equals increased fuel economy, Even Jester should give credit there. I Just cant afford 13 MPG anymore thats why I went with an AFB, that and I cant find any good virgin Qjets to ravish anymore.

 

re-Qjets Yeah, at least not for cheap anyway

I agree on the fuel economy issue, and don't forget the Tquad in there too.

Some factory equipped Holley 600's came with annular discharge boosters on the primary side and were decent on mileage.... cept for the ones with damaged powervalves or leaky gaskets.
Same for the spread-bore Holleys, but they came with generic boosters.

 

I'm not set on swapping... I'd take gas mileage over power considering gas is at least $2 a gal for regular old 87 octane! The A/F gauge shows that my motor is going lean past 4000 rpm so I want to fix that with some metering rods. I want to get the freakin' stalling problem over with 1st though. I know that there is more in the top end with my combo and that this carb is not giving it to me. I'm not experienced at all realy with working on edels so it gets annoying sometimes.

 

Wow didn't know it was leaning out on the big end too. How lean is it going? You getting lean misfires or detonation? spots on the plugs?

IMO a better way to richen up the big end @WOT would be simply jet up the secondaries & leave the primary system alone (rods included).... that is if your drivability is good already.

Edelbrock sells upgraded needle/seats that are spring loaded and can solve a lot of stalling problems. Vehicles that have a very bumpy ride and 4X4's use these a lot. They may help you.

 

It goes pretty lean but not enough for it to detonate....but watching my a/f gauge...(digital one) it pretty much goes blank. So it's probably going pretty lean....If it was tuned I would really get more top end power for sure. It bogs sometimes when I launch it too, I don't know to much about Edelbrock carbs but usually you can do some accelerator pump tuning and get a quicker squirt to solve this problem. I don't know If it's the same on edelbrock carbs. I was thinking of going 1 power stage rich...but I cruise at stoich a/f mixture...It gets about 20mpg on the freeway at 3000-3500 rpm...so I guess I am pretty happy with that, but I could always go for more gas mileage, always.

Tell me what you think I should do. The stalling problem is a real pain....tell me, Do cars stall sometimes because the a/f mixture at idle is too rich?

 

on this page of my site about 3/4 of the way down there's some info about modifying the pump shot on Edelbrock
http://www.cardomain.com/member_page...217306&page=26


Idle can go either way but way more times than not a rich idle doesn't stall the car, but a lean idle will.... as in a blocked idle fuel or idle air-bleed passage.
A simple vacuum leak will not stall the engine though.

If it's stalling a lot at idle, the VERY first thing I'd suspect would be flooding/leaking fuel especially if the plugs come out wet or very black sooty after it dies. If that's the case with your edelbrock then it's probably the float & needle/seat mechanism not working right. It only takes a small particle of dirt or piece of old rubber fuel line to cause the needle to stick open on these carbs.
It's easy to check and fix.

Like I said, the other possible option is that an air-bleed for the idle circuit may have gotten blocked. A blocked air-bleed here will cause idle to be rich. Having to open the throttle too much for the idle setting can do the same thing because it brings the transition circuit into play.
Maybe this picture will help point out the passage I'm talking about.

 

How do I lower them properly? I really get hasty on getting over zealous on screwing with the carb cause this is my daily driver.

 

Ever hear of O2 sensor saturation? When the stock O2 reads a rich enough mixture its voltage drops which would make for what would appear as a very lean condition on one of those nearly worthless LED gauges. Its quite common, and it has happened to me when ive jetted too rich. If your carb is not jetted rich enough its not going to just drop out dead lean all of the sudden like what you are witnessing.

The stock O2 is remarkably crappy for tuning WOT, and there are alot of things you should know about it before you go placing all your stock in it.

As far as this silly talk of holley carbs generating 20 hp more than an edelbrock... thats all it is, silly talk. I pretty much concur with everything Fbird 88 said.

 

I agree pretty much with this guy as well. I'd trust plug readings much more than that guage.
If you went that lean I'd also expect you to feel very strong surging and misfires... then also see signs of heat & detonation on your plugs. It is more likely that you'd be too rich & that can indeed make it feel sluggish on the big end.
Hopefully you did several system checks to make sure things are working like they should... as in I mean make sure you have no dead or dying sparkplugs or wires, making sure your secondaries are opening fully at WOT.
If the secondaries aren't operating right, that would make you run very rich at high RPM. Sometimes the stock (even when new) linkage connection between the primary shaft & secondary shaft can bind, sometimes the choke's secondary lockout mechanism can stick, and sometimes the secondary blades themselves will bind against something.... especially if you run a 4 hole spacer under your carb.
The width of your secondary bores is around 92mm,
the width of most 4-hole spacer bores is only around 88mm
and there's a possibility of binding unless you open up your spacer to match the carb.
Just some things to check.
I will post up a pic of how to adjust the floats after work today

 

 

Good Pics

 

Thanks for the compliment.
I forgot one last night....

Just measure here to see how much you've adjusted. It doesn't have to be exactly 1/2" between the float and air-horn with it flipped upside down.... that's just a good place to start.
You can increase this measurement which lowers the fuel level quite a bit, but you don't want it so low that you run the bowls dry at WOT.

 

Do I need to remove the float from it's seat to do this. I know thats the way you displayed in the pic, but I was wondering if i can do it while it's still attached.

 

sure can,
no problem. Just grab a hold with the needle nose to take pressure off the needle so it doesn't get smashed while you bend the metal of the float.

 

I'm running an Edelbrock 750 on my 357 SBC; no problems.