# Holley or Edelbrock 750??



## Instg8ter (Sep 28, 2010)

Good day in 8ter land, sold my extra 455 short block for 400.00 in need of a few sleeves, and picked up a holley dbl pumper 750 for 25.00, so now i have both holley and an Edelbrock, was wonering which would compliment the motor better, heres the specs

MOTOR:
455 + .030
trw forged pistons, on stock re-conditioned rods
Moly rings
6x-4 heads 3 angle valve job and skirted valves, .062 Titan head gaskets with zero deck to get under 9.5:1 CR
with street port matched to edelbrock performer manifold w/e-750 carb
1 7/8" primary hedman headers into 2 1/2" exhaust w/true X pipe
scorpion alum roller rockers, 1.50 (i think, how do you tell?)
comp cam guide plates,HD springs, lunati hyd lifters and hardened push rods
Lunati 307A2 hyd cam .454/.454 lift w/1.50 rockers 276/286 dur
N crank balanced and align honed .20/.20 polished and chamfered
clevite 77 bearings
Mr. gasket HD chrome fuel pump
Tuffstuff chrome 100 amp alt
Powermaster high torque mini starter
milodan 6 qt oil pan
melling high volume oil pump
HEI recurved for 455 (MSD 6a with 50,000 volt coil if needed)
dual CAI from behind high beam buckets
MSD 8 mil wires
autolite 666 plugs
power steering
keeping manual brakes w/disc front conv. for now
TH -350 trans stage two shift kit, 2700 stall converter
open rear end w/2.56 gear (in search of 3.23 posi)

just found out what the mystery roller rockers (no markings) are that came on the 6X heads, they are Harland Sharp HD 1:65's , not the 1:50 i listed....how much lift will that add??


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## Eric Animal (Oct 28, 2007)

I don't know much about the Edelbrock carb. Holleys are easy to work on. Therefore, I would go with a Rochchester Quadrajet, they work well and sound cool!


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## jetstang (Nov 5, 2008)

Edelbrocks get better MPG and are easier to jet if you have a trick kit. Holleys make more power and look cooler.


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## BearGFR (Aug 25, 2008)

Eric Animal said:


> I don't know much about the Edelbrock carb. Holleys are easy to work on. Therefore, I would go with a Rochchester Quadrajet, they work well and sound cool!


:agree Cliff Ruggles wrote the book on Qjets (literally, you can get it from him here and also the usual book stores). Garden variety QJets flow 750 cfm, and some versions like the one that was built for the 455SD flow 800. A wamred up 455 might need more than 750 cfm (regardless of whose name is on the tag) if it's still making power above 5000. Personally, I don't "like" Holley carbs but that's only because I tend not to "like" anything the great unwashed masses of ::cough:: Chevy-dom seem to flock to. 
I've got an 800 cfm QJet on my 461, and so far - I love it.

If I was objectively trying to make the best possible power, I'd pay close attention to what Jim (Mr. P-Body) has to say.

Bear


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## Instg8ter (Sep 28, 2010)

I am leaning towards the Edelbrock as it is brand new and a few miles per gallon extra don't hurt, using performer manifold also with 1/2" spacer and the car will mainly be a cruiser. Also have a torquer, maybe I will combo that with the holley and test them in the summer once i get her broken in. Could not pass on the holley for 25.00. actually got the Eddy for 100.00 new in box. I know most will say get a QJ but fact is i am on a budget, so as soon as i find an amazing deal on one i will probably add it to the stables..LOL Still working on saving for a suitable rear end, looking like i will be running the peg leg this summer as the rear end the way i want it will be a 3K proposition.

Hey Bear, what kind of effect will the 1:65 rockers have on my engine numbers as i think i told you they were 1:50 when you ran the engine analyzer on it. They have no marking at all on them, did my research and found out they are Harland sharp 1:65


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## Rukee (Feb 8, 2007)

Be unique, get a dual 4bb manifold and run them both!! :willy:


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## Instg8ter (Sep 28, 2010)

:rofl:....now theres a novel idea Rukee, that would turn some heads with the hood up.


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## 66tempestGT (Nov 28, 2009)

i dont think you should clutter up your shop with anything as worthless as a holley carb. i will send you the 25 dollars back for it. as the owner of a pontiac with a chevy engine its the only honorable thing to do.


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## jetstang (Nov 5, 2008)

Qjets either run good or bad, no middle ground, if you find a good one you are Golden. I am a Holley guy, love them, and run them all the time. Edelbrocks I'm still on the fence, like the ease of adjustability, but have swapped one out for a Holley and it was night and day. Secret of the carb is to have it correctly jetted and adjusted for your application. When you get into carbs and all the variables there is a ton of HP in a carb, that's why there are $1000 750 Demon carbs and the like. I don't feel the Qjet is the end all carb for any application, 50 year old technology...


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## BearGFR (Aug 25, 2008)

Instg8ter said:


> Hey Bear, what kind of effect will the 1:65 rockers have on my engine numbers as i think i told you they were 1:50 when you ran the engine analyzer on it. They have no marking at all on them, did my research and found out they are Harland sharp 1:65


H&S are good rockers. Depending on which ones they are, they could actually be closer to 1.72:1. Having "bigger" ratio rockers does two things: give you more lift at the valve than what you'd get with 1.5:1, and also lengthens effective cam duration a tad over what you'd get with 1.5:1. One thing you're going to want to be sure and do with higher ratio rockers is remove the heads and elongate the pushrod holes. The bigger rocker ratio and also the fact that they move the pushrods slightly closer to the rocker stud usually means the pushrods will rub on the heads unless you elongate the holes with a die grinder or Dremel tool.

Bear


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## Instg8ter (Sep 28, 2010)

hey Bear, they were all ready clearanced for the heads as i purchased them complete on another motor that had a little scaring in two bores.(just sold short block for 400) from some antifreeze that was not cleaned above rear pistons. i will double check them when i set the lash. what kind of gains will i see from the higher lift and more open time?


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## BearGFR (Aug 25, 2008)

Instg8ter said:


> what kind of gains will i see from the higher lift and more open time?


Uhhh.... some?  Don't expect anything overly dramatic, in fact it might require a dyno or a trip to the track to collect some time slips to detect the difference.

Bear


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## Thumpin455 (Feb 17, 2010)

Holleys are just as old as Qjets, but Qjets are more adjustable than a Holley. That adjustability is a detriment to someone who doesnt understand carbs, or simply doesnt know what everything on it does. The Qjet can be rebuilt to run quite well, it just takes a bit more knowledge. Qjets can get very good mileage while making the same power as a Holley. No power valves to blow out, and they have good throttle response with the small primaries. Lots of the problems with them were due to people messing with them unknowingly, and from varnish and stuff clogging inner passages. I like the adjustability of the air valve secondaries. With an allen wrench and a flat screwdriver you can make them open fast so it bogs, or barely open at all in seconds. 

Holley is simple, easy to tune, and they make good power. I like them quite a lot. There is probably 15 of them on vehicles or on the shelf in the shop here. Once again you have to know how to tune one, at least a bit, to get it to drive nice and make good power. They are easy to screw up, and that is how I got so many of them cheap. Guys jetting them way too lean, not knowing what things did and not being able to get them to run right. They work good for me. 

Edelbrock carbs have been a source of annoyance for me. They run pretty well on stock engines that dont require lots of airflow. They are easy to tune too, no need to drain a float bowl, just loosen a screw, turn the cover a bit and the rods pop out for you. The simplicity comes at a price though, you cant adjust the secondary air valve easily. It has a weight rather than a spring, so you need to add or remove weight to get it to open faster or slower. You wont lose a power valve with a backfire like older Holley carbs can, because they dont have one. I have an 800 on the shelf that never ran right on my 72 HO Formula. The Qjet I built for it works great, as does any of the Holleys I put on it. I wouldnt say they get better mileage, just that they tend to not be as rich as most Holley carbs can be with the float level being too high, or any number of other things. The only engine where an Edelbrock did better than one of my Holley carbs was my brothers 360 Dodge in his Challenger. That cold blooded thing backfired so much he couldnt keep a power valve in a Holley. The Holley ran faster at the track, and used less fuel until the PV ruptured, but the Edelbrock worked better on his near stock engine. 

I like the older Carter AFB carbs, have a few of them laying around as well. Much better than the Edelbrock carbs I have worked with.

For a daily driver I like the Qjet. 
For power and quick tuning changes I like the Holley.
For a paperweight I like the Edelbrock.

I might dig that E carb out and see how it likes to run on ethanol this summer.  It cant hurt anything thats for sure.


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## jetstang (Nov 5, 2008)

:agree I wish I knew how to trick tune a quadrajet, I can rebuild one pretty good, have had good luck and bad, hence my comment. 
As for Carter AFBs, I got a 66 SS396 Chevelle back in the day with dual 4s on it. I couldn't get the leather power valves to seat or work. It got 3 MPG due to the carbs dumping. I took them off, put a cast iron intake on with an adapter and 750 vac sec Holley and the thing was streetable and got 10 MPG, and is still the quickest car I have ever driven, but it had a solid cam, 4 speed and 4.88 gears!! Maybe not the quickest as it never hooked, could blow the tires off at 40 MPH..


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## Instg8ter (Sep 28, 2010)

Hey Thumpin, hows things in the UP? I ordered the tune kit for the Edelbrock and am getting a rebuild kit for the holley to get it back to factory specs, never hurts to have a backup. And i will probably pick up a Qjet when opportunity arises


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## Eric Animal (Oct 28, 2007)

I wonder how dual 750 Q-jets would work ontop an 871SC.......


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## Mr. P-Body (Jan 20, 2011)

Harland Sharp and Smokey Yunik "teamed up" around 1960 to "invent" the roller rocker. Yup, Pontiacs were "first"!

If checking the ratio of an HS rocker with "light" springs, it will ALWAYS measure "higher" than advertised. The reason is "deflection". HS rockers are fairly flexible by modern standards. While "checking" ratio may be 1.72, "running" ratio is much closer to the advertised 1.65, as the rockers literally "bend" a little, reducing the ratio. 

We use E-carbs on relatively stock small block Chevys. Not much else. Holleys are excellent when you get the RIGHT one. LOTS of choices, making that somewhat of a "task". 

Agreed, Q-Jet is among the better choices. Unfortunately, as others have said, not a whole lot of knowledge and expertise "out there". Cliff is good. Tom (MarylandBandit, TAC) is also good. I've heard The Carb Shop does a decent performance build on them as well. You can call AED and have a 750"HO" on your porch tomorrow... Take it out of the box, bolt it on, and go quicker than you EVER have.

Jim

FWIW


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## Instg8ter (Sep 28, 2010)

thanks Jim, probably gonna run with the Eddy now and save my pennys for a fresh Q-jet, budgets getting a little tight and i still have a pretty big hit coming for paint, will probably baby it this summer anyways, everything being fresh...:cheers


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## DEMONDSPN (Feb 19, 2011)

you really shouldnt ask an opion on carbs be cause they are all good carbs if there tuned right . if you want a really good carb quik fuel is the way togo . but again there 1000.00s its all about personal preference . ive tuned alot of carbs and made good rear wheel hp with all of them . edlebrocks are not hp carbs but they can be .


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