BIG BLOCK BOYS: headers & carb help

[humbulay]

BACKGROUND:
I have a 71 C10: had factory 350; stole my dads 1973 454 out of his old truck that had been parked for 10 years ( I'd been begging him for it for the last 7yrs to no avail so I just yanked it, tore it down & had it machined .030 last winter when he went to florida for for 4 months ) anyway;

HEADER CHOICE:
I noticed there is a lot of discussion about header headaches, my 71 has a stock stance/700r4 & a new full dual exaust that would bolt up to full length headers, I heard those $100 autozone or advance header fit well???? I've heard about ground clearance issues, does that only apply to lowered trucks? anyone w/ a similar set up that found the right ones?

CARB CHOICE Close to stock rebuild w/ RV cam; moderate compression ratio; most likely going to put a performer air gap or a professional-products air gap (if you havent heard of 'em before, thay make nice stuff> check them out) http://www.professional-products.com
I want to get the best power/performance possible without the need for a 3500 stall and be able to keep it reliable. 750cfm? 870 cfm? be sure and tell me what I dont want! basically what's tried/true/reliable and will help to whip the mustang geeks, ricers and vettes

[71/454]

I run hedman shortys in mine it is lowered though they're originally for a 71 monte carlo fit real good except collector was a little close to the brake line tee so i bent it a smidge. I run an 800 holley double pumper. Carb choice can vary due to your height above sea level, so you may want to consult someone local. We're at 3800 ish feet here so i started with a 650. just my 2 cents

[lilpup69chevy]

well i don't know about the 870 street avenger but i'd steer clear of the edelbrock imo if you want the best performance go with the holley on my built up buick 455 i ran a modified q jet that flowed at 830cfm and did better than any other carb then i changed it and went with the 850 double pumper and it did perfecto once i figured out what jets i needed the problem i had with the double pumpers i've tried as they moved plenty enough fuel but not enough air for my engine but then again it was in a race car. so i'd try the 870 street avenger out of the choices you listed

[bskylerj]

I would first add the Mighty Demon to your list. I know several people that have been running the Demon carbs including myself and they work well. I would think if you want performance I would do a 2500 which would be good for you to about 2200 rpm or so to give that little extra shot out of the hole. I am running the shorty headers as well and like them.

[Robznob11]

well this poll is not worth having. it does nothing but send the wrong message to some one that does not know how engines function. every thing depends on the internals of the enging and how hot it is. you would not want to run a 1050 carb on a 396 with small oval factory heads , with small valves and a mild flat tapped cam. but if you take the same engine throw on some afr heads, bump up the compression, and throw in a big roller cam,large headders and a single plane intake, that carb would work well, best i can tell you is on a totaly stock 427-454 750 is probably enough, throw in some reworked heads, headers and cam 800-850, tricked out heads, radical cam, compression bumb,850+ carb, rember just because you buy a big 292 cam that don't mean you need a big carb, becuase if you did not do anything to the heads, intake,and exhaust your just pi$$in in the wind anyways, oh and don't be temped to hog out your cast heads or throw in huge intake valves on a bb, the exhaust valves are what kills gm bb heads not to mention there only a few that are designed well any ways.

[humbulay]

Just to clarify~

the carb poll relates to the .030 over 454 I am currently building as decribed in the thread....basically stock rebuild w/ RV cam and an air gap intake
I am interested in opinions on what would be the best manufacturer & CFM for my motor, not just big blocks in general.

[Robznob11]

sorry about the miss understanding i did not see that part, and just to let you know a 750 will be fine for that set up a 750 dp holly would be optimal. 870 to much youll have issues of it falling on its face when you stomp it. not to mention watering everyones eyes thats behind you...lol

[bryanw1968]

I would go with a Barry Grant - Mighty Demon probably a 750 vacuum secondary. Also, I think a 3500 stall is way too much for an almost stock cam. That cam is going to start making power WAY earlier than that and you won't be able to take advantage of it. I would go with something slightly higher than stock. Maybe 2000-2200? You want the cam and convertor match as closely ass possible. Also, the bigger the stall the more heat you're going to have to deal with. Not a big fan of the air gap personally unless your truck weighs about 3000lbs and you're going to make top end power only.

Not sure on the hedder solution.

[humbulay]

Not a big fan of air gaps eh? what did you have & why didn't you like it? I've got my eye on a pro-products air gap that claims a 1500-5500rpm range, but i'm not dead set against a dual plane eiither.

[rwgregory]

In my opinion, a '73 454 is not exactly a horsepower king. It sounds as though
it will be relatively stock w/an RV cam, intake & headers. I would go with a
650 Holley double pumper w/mechanical secondaries. The smaller CFM will
keep your bottom end acceleration snappy & crisp while you can put larger
jets in the seconderies for when you stand on it. Not to mention, at over 3
bucks a gallon, the 650 will be a little better on fuel consumption.

[Stroker]

Edelbrock 750 on a Performer or Performer RPM would be my choice. I've found the Edelbrock carbs to be very reliable and the 750 Edelbrock factory tuning is well suited for a mild 454. A properly set up Q-Jet would also work great for you with a spread bore intake. I like the Holley HPs and BG they are more tunable and can make a little more power if properly tuned. But with your engine specs the gain is not going to be much. The Edelbrock will likely be an install it and forget it deal. Airgaps are fine intakes but if you plan to use your truck in cold weather I wouldn't recommend one.