gilly327

hello, i have 350 bored .30 over.comp cam XE268H,weiand stealth intake and trick flow super 23 heads.i have a edelbrock 600 and a holley 750 double pumper carbs,im not sure which carb to go with.i was leaning towards the 750 but dont know if it will be to much.Maybe a totally different carb would be good.any help is appreciated thanks.

five7kid

iTrader: (14)

750 won't be too much. The 600 is an Edelbrock.

Which car is this going in? What will you be doing with the car after the engine is in?

gilly327

its going into my firebird.just building a street car.

blue85305

not to threadjack, but five7kid, i was wondering why you always advise against edelbrock carbs. I've used several with absolutely no problems. again just wondering.

five7kid

iTrader: (14)

Well, blue, have you used anything else?

gilly327

i went to the holley web site for info and they said mechanical secondaries are for manuel transmissions.they recommended i use either 600,650 or 675 cfm vaccum secondary. oh ya should be 10:1 as well

blue85305

well 57, no i haven't, but thats not on point; all i did was ask you why you always advise against them. I just wanted to know why you feel the way you do about them. maybe theres something that i don't know that you could shed some light on. theres no reason to answer a question with a smart *** question. so i ask again, Why do you feel the way you feel about the edelbrock carbs. I've read you advise against them for several years and have yet to see you state why.

five7kid

iTrader: (14)

DP vs. VS: Holley's recommendations are based on the typical novice "bigger is better" thinking. So, they put an 850 double pumper on their stock 305 automatic and don't understand why they can't floor it from idle without major bog and sputtering. But, an 850 VS simply won't open the secondaries on that carb, so it's "okay". As long as RPM's are above a certain point for a given engine displacement and double pumper CFM, you won't bog. Go ahead and put a DP on an engine that has an automatic behind it as long as you stay above the line on the chart.

Edelbrocks: The carb design predates the q-jet. It is a square bore with non-adjustable secondary air valve (although the Thunder series does add AV adjustment capability). It is a downgrade from a q-jet, especially a CC q-jet. It's the cheapest carb available, and the old adage that you get what you pay certainly for applies here. Unless you don't have either carb or money, or you're desperate, it is not the right choice for any application.

blue85305

it's based on the carter AFB, which was spun off to the carter competition. A carb that was used on alot of the racecars in stock and super stock classes in the 70's, Now i know that those cars were not as fast as they can be built today, but the fact remains that the carter carbs were very good, and even marketed to REPLACE quadrajets. If you have a problem with the edelbrock carbs thats fine, but don't trash everyone that asks about them. How many of them have you used? How much experience with them do you have?

marine68

hey blue, i agree that this moderator doesn't like carters or edelbrocks. the 60/70 dodge/plymouth muscle cars with the 426 hemi that were factory rated at 425 horsepower but actually dyno at 800 plus used a dual plane manifold with carter afbs. they were good enough then and good enough now. the new edelbrocks are made by magneti-marelli and they know alot about performance since their products are used in formula one racing. i also have used carters on my old mopar but now my 89 iroc has a edelbrock 1405 and i am sure it will run great.

mooch1

hey guys, i need some expertise from you..i have edelbrock 1405 on my 350... it has the stock fuel pump , is it true i need to change either the fuel pump and put it one from edelbrock that produces 6psi,,or get a fuel regulator that adjusts to 6 psi...with the stock fuel pump it doesn't run right ,.i find it is getting way too much fuel..what do you think ?.is this right about the lower psi for edelbrock carbs?

marine68

if you have an in tank fuel pump that is for fuel injection, it is pumping way too much pressure. you need to install a regulator before the carburetor and adjust it to 4 to 6 lbs pressure. i had to do that because i converted from tune port injection to carb.

//<86TA>\\

iTrader: (14)

that just not true, most street hemi's dynoed a bit over 500, the race hemi was 800.

I have used edelbrocks and holley carbs, and the difference is night and day. I will never use an edelbrock again.

mooch1

well i have a mechanical fuel pump that produces slightly higher than the 5.5 psi pressure recommended by edelbeock for their permormance carbs, i put in an inline fuel pressure regulator set to 5.5psi...it works great and gives the carb constant pressure...i have had holleys and now i have switched to an edelbrock...i have to say that these carbs are good and are getting a bad rap...holleys are known for their quick acceleration and are great for performance...but they require maintenance and guzzle way too much for a daily driver car or even a weekend car like mine...the edelbrock gives you preformance and a slightly better fuel economy..easy to adjust and rebuild if you have to, you can go on their website for help or even call and speak to a tech...holley doesn't offer this much support...so i think just because you don't like something , it doesn't mean it's not good ..like brocolli!!!...i think it all depends what you do with your car...just my 2 cents..

mooch1

i have installed a 5.5psi inline fuel regulator like edelbrock suggest and now it runs like a charm, no problem with edelbrocks here!

Rayzor32

iTrader: (1)

I'd go with a 650 double pumper, maybe a 700 if your cam was solid, it will be the best for performance and good on the street. Probably will only require some tuning to the acc. pump circuit. I think a 750 is too much for the street.

That edelbrock would be too small for the strip, it will work fine on the street but I think it will be limiting the full potential of the engine, a 750 eddie or 650 AVS would be better. The eddies are great for the street not as good as a modified q-jet would be, but the carbs are so simple and are by far the most user friendly design. You could cut the choke horn off of the 600 and grind it smooth and file the throttle screws flat to get some more airflow out of it.


Five7- they might call the edelbrock a "squarebore" but if you look at the 600 performer model, the primaries are smaller than the secondaries, not as dramatic as a q-jet but definitely a lot smaller. Also with dual pattern bolt holes I don't know what to call this carb. I think the 800 AVS is the only one that has equal size barrels. The AVS are adjustable air valves, though I never had many problems with the secondary opening of the AFB's, I prefer them to vacuum secondaries. Also the eddies are more expensive used than holleys are, but they are cheaper new.

I have a prefernce for all 3 carburetors I think its more about matching them for the application and what one is more comfortable with/has invested $$$ in.

Since you have both carbs i'd try them both and decide for yourself which is better.