Rebuilt Qjet, Edelbrock, or Holley- pick one

sandman · Posted: Wed Jun 18, 2008 7:20 pm Post subject:

dougs85: AGREED! No one can read all comments on all topics here, and I too missed toms84ss comments. Bring it! Please briefly fill us in again and share your opinions tom, any advice is welcome.

I've learned a lot already, and truly appreciate people sharing their experiences and thoughts here. I want to make the right call on my carb fix, as I've owned this '79 since new and want to get it running well again.

toms84ss · Posted: Wed Jun 18, 2008 8:31 pm Post subject:

I agree the Q-jet is a good carb when its running right. Problem is most people dont know how to work on them. Let alone the CCC version. That being said, if you dont have to have emissions, I say pull it all off. Get a standard HEI and what ever carb you like. I like Holleys ALOT! I said it before and I'll say it again. You can tune a non CCC carb to get just as good of fuel mileage as a CCC version and you can do it at home. Get a wide band O2 sensor and tune away. Yes, I know they are expensive. But, it will pay for it self over time with increased fuel mileage. And, if you tune for power, it could save you a rebuild if you get too lean at WOT or with nitrous. Plus, you can use it on your buddy's car and make some coin. Not trying to start a kissing contest. But if you dont have emissions in your area, you have a lot of choices at building up your car. Carry on gentlemen.

79ElkyFl · Posted: Wed Jun 18, 2008 9:25 pm Post subject: Carbs

You have to look at it in prespective.A newwer (computer controled)cc carb will probably out preform an older non cc carb but the change made to the carbs at the time of the change was not fuel efficency but emmissions it is like comparing an apple computer from 1980 to a brnd new mac it is night and day tecnology has come a long way and older computer controlled carbs left somthing to be desired.I am sure that there are people that have had great experiances with both but with propper tuning they are equaly effective.Neither is better or worse it is just easier to fix yourself the oldschool way.

toms84ss · Posted: Wed Jun 18, 2008 10:23 pm Post subject:

A "newer" computer controlled carb is already 20 years old. How new are you talking about? When you say "out perform" what do you mean. More HP or mileage or both? When they were designed to clean up emissions, they had to run as lean as possible. Lean A/F ratios dont produce big HP numbers. The lean conditions helped in the mileage department. But emissions were the biggest concerns at the time.

elcamino74guy · Posted: Thu Jun 19, 2008 12:08 am Post subject:

I always liked the AFB/Edelbrock designs because they were so easy to work on and tune. I have a holley Avenger 670 now and I actually had to get richer jets in it to make it run right. I've already mentioned a few issues I've had with it such as the leaky fuel bowl to main body area and the choke problem but so far so good. This is the first Holley carb I've used as previously all the others were AFB's and Q-jets.

I like the power potential of a Qjet but it is the hardest of the 3 I've mentioned to work on. It's also more sensitive to float level in my experience.

Anyway, I'll work with anything I have available. I had a progressive 2 barrel Nippndenso carb on my 90 Toyota Pickup. I had that truck for 100K and never had an issue with the carb. I've heard of people who did though.

As for lean conditions for emissions, it's true it makes the engine use less fuel but it also heats up the combustion chamber which should help with combustion but usually just ends up causing detonation which a CCC system will likely respond to by pulling back timing. So you end up with a really sluggish motor that eventually fouls plugs because it will overfuel at some point because of the reduction in timing causing more raw fuel to end up in the combustion chamber...and on..and on.

If I had a vehicle with early 80's emissions and I didn't have to deal with smog testing I'd pull the emissions stuff off of it except for the PCV and go for a carb that was sized correctly for the engine and tune it a bit lean but not so much as the factory would. I'd also improve the intake system and maybe work the heads over so they breathe better.

If I had to deal wtih emissions I'd probably park the car till I had enough money to switch over to fuel injection and bring over whatever emissions equipment (AIR pump, EGR, etc) the state required.
Smile

_________________
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79ElkyFl · Posted: Thu Jun 19, 2008 12:16 am Post subject: Explination

I should have worded it better I meant to say that a brand new off the shelf carb would preform better at whatever application that you wanted hp or mileage than a 25 year old rebuilt carb.The original post was rebuild vs new and what brand I was just refering to that question.My point is taht I would rather rebuild a non CCC or get a brand new carb from the parts store than try to fiddle with an old CCC.

old_coot · Posted: Thu Jun 19, 2008 6:33 pm Post subject:

Let me give a brief introduction of myself for those that don"t yet know me. I am sixty one years old and a certifiable car nut with no particular affiliation to any brand---other than it has to be from an American parent company----I know there are some fine automobiles made outside our borders and without our design input---but they don't do anythig for me. At one time or another I have owned at least one example of every engine produced by the "big three"with the exception of some of their four cylinder engines. I do not believe I have left very many of them completely stock so I have some experience but make no claims of "expert"status.....Now back to the question at hand---we were asked for our opinion about carbs and I gave mine---for those that know me I am sure they will confirm that when asked I always advise everyone to go fuel injected---its that much better---its a bit expensive but worth it in my opinion but thats because I drive all my cars a lot---no trailer queens for me--as for carbed cars I haven't owned one in about seven or eight years now so my experiences are from that era ---what I found was that the quadrajet was the best overall carb but it did require some skill in getting it tweaked---tops in economy and very respectable in performance, the Edelbrock, which is pretty much a copy of the old AFB was so so----fair in performance fair in ease of tuning and fair in economy---Holley was easy to tune, tops in performance, but not very economical NONE are in the fuel injection arena for drivability or economy---new computers can simply adjust to changing conditions like no carb is capable of --without exception---again in my opinion
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I don't think I have ever had a car that was "FINISHED"........unless it was totaled.

sandman · Posted: Sun Jul 13, 2008 5:36 pm Post subject:

Well, this has been interesting and educational for me. I'm glad I asked the question here and appreciate the responses. Seems as though there is no clear answer or best overall carb- opinions vary. That said, this comment from toms84ss struck me:

"You'll have to change some things to get a Holley or Edelbrock to bolt on. Q-jet would be the easiest to go with."

I don't really want to adapt, fabricate, improvise, or mess around to make another carb fit. And, it doesn't seem clear cut that the Edlebrock or Holley are that much better to make it worth it.

sandman · Posted: Tue Oct 07, 2008 10:08 pm Post subject:

Update: I found a carb rebuilder selling Quadrajets on eBay- goes by Mountain Man Fuel Systems, from Arkansas.

Got the carb from him, it's installed. Cost was $230. They use an electric choke conversion, which is simple to do.

HIGHLY RECOMMENDED! I made the right choice going with another Rochester Quadrajet over the other two options, and am very happy with Ted's work and service. Check him out on eBay if you're considering a replacement carb. Happy

dougs85 · Posted: Wed Oct 08, 2008 12:28 am Post subject:

Glad to read it worked out for you. Thanks for the update. There was a lot of give and take on this topic and a lot of personal experience exchange. I think a lot of us benefited from the information.

Doug
_________________
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87 El Camino 305, 2004R, K&N, dual exhausts
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