i have a brand new SBC 434 stroker with a holley 250 searies supercharger..and i dont know what size carb to run ..went to holleys web site and that was no help........:CRY: does any one have any info? need some help here......
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i have a brand new SBC 434 stroker with a holley 250 searies supercharger..and i dont know what size carb to run ..went to holleys web site and that was no help........:CRY: does any one have any info? need some help here......
GOT THE NIFOQuote:
Originally posted by STREET-DREAMS-2
i have a brand new SBC 434 stroker with a holley 250 searies supercharger..and i dont know what size carb to run ..went to holleys web site and that was no help........:CRY: does any one have any info? need some help here......
cubic inches times max rpm divided by 3456 will tell you what size carb you
will need.
so...
434 times lets say 6500 rpms divided by 3456 = 817cfm that you will need for
your motor.
more rpms bigger carb
that might be true with a reg. motor, but im not sure with that blower.how much boost are you running? 10 lbs. of boost will make a big dif. in carbs. compaired to 6 lbs. and you can get by with less carb. on the st. with the blower than if you are gonna drag race it. what knd of boost do you have and what are you gonna do with it? :HMMM:Quote:
Originally posted by STREET-DREAMS-2
GOT THE NIFO
cubic inches times max rpm divided by 3456 will tell you what size carb you
will need.
so...
434 times lets say 6500 rpms divided by 3456 = 817cfm that you will need for
your motor.
more rpms bigger carb
[QUOTE]Originally posted by lt1s10
that might be true with a reg. motor, but im not sure with that blower.how much boost are you running? 10 lbs. of boost will make a big dif. in carbs. compaired to 6 lbs. and you can get by with less carb. on the st. with the blower than if you are gonna drag race it. what knd of boost do you have and what are you gonna do with it? :HMMM: [/QUOT
LOOKING TO RUN 9 TO 12 LBS OF BOOST...STREET/STRIP.....
[QUOTE]Originally posted by STREET-DREAMS-2
thats a lot of boost what size blower is that? will it put out 12 lbs of boost?Quote:
Originally posted by lt1s10
that might be true with a reg. motor, but im not sure with that blower.how much boost are you running? 10 lbs. of boost will make a big dif. in carbs. compaired to 6 lbs. and you can get by with less carb. on the st. with the blower than if you are gonna drag race it. what knd of boost do you have and what are you gonna do with it? :HMMM: [/QUOT
LOOKING TO RUN 9 TO 12 LBS OF BOOST...STREET/STRIP.....
for the amount of fuel it will take to get you though the 1/4 ml. with 12 lbs of boost you will be changing carb to drive it on the st. unless you know what you are doing you will be better starting off some where around 6 lbs. of boost. been there done that.:CRY:
Quote:
Originally posted by lt1s10
thats a lot of boost what size blower is that? will it put out 12 lbs of boost?
HOLLEY 250 POWERCHARGER WITH A 400 CID AND A 91005 DRIVE PULLEY IT MAKES 10-11 PSI
THE MAX BOOST FOR THIS SUPERCHARGE IS 12-13 LBS. BOOST OR ATLEAST THATS WHAT THE INSTRUCTION/TECH MANUAL STATES...Quote:
Originally posted by STREET-DREAMS-2
HOLLEY 250 POWERCHARGER WITH A 400 CID AND A 91005 DRIVE PULLEY IT MAKES 10-11 PSI
Quote:
Originally posted by techinspector1
The size of carb(s) or CFM required for a given application can be calculated by the following formula A: {(CID x RPM) ÷ 3456} x {Boost ÷ 14.7) + 1} = CFM required. The amount of CFM required will determine carburetor size and quantity. If you try to use a carb with less CFM than required, performance and economy may be greatly reduced.
434 x 6000 / 3456 x10 / 14.7 + 1= 1,265 cfm
YOU LOST ME ON THIS...... 1,265 CFM= 2 650CFM CARBS
if you have never run a blower you need to do some reading up on this thing, because it easy to break up a lot of stuff using the blower. you need to get that boost back down to something you can live with until you learn a little more about it you will be surprised at what 6 lbs. of boost can do. if i was you i get me a good book, on blowers, use the chart that tech just gave you, use about 6 lbs. of boost and start there. i ran one a few yrs and broke up a bunch of stuff before i did some series reading up on it and once i got to under stand them, then i had a lot of fun with it. **) **)Quote:
Originally posted by STREET-DREAMS-2
THE MAX BOOST FOR THIS SUPERCHARGE IS 12-13 LBS. BOOST OR ATLEAST THATS WHAT THE INSTRUCTION/TECH MANUAL STATES...
Quote:
Originally posted by lt1s10
if you have never run a blower you need to do some reading up on this thing, because it easy to break up a lot of stuff using the blower. you need to get that boost back down to something you can live with until you learn a little more about it you will be surprised at what 6 lbs. of boost can do. if i was you i get me a good book, on blowers, use the chart that tech just gave you, use about 6 lbs. of boost and start there. i ran one a few yrs and broke up a bunch of stuff before i did some series reading up on it and once i got to under stand them, then i had a lot of fun with it. **) **)
WELL LETS SEE NOW....I'VE BUILT A 80 MALIBU WITH A 355 SBC WITH A 144 B&M BLOWER WITH 8LBS OF BOOST.... IN THE 1/4 THE CAR RAN 11.82@115 MPH......
NOW I HAVE A O-RINGED 434 STROKER WITH BRODIX 2.08/1.60 VALVES VENOILA N/20 TURBO/BLOWER PISTIONS SRP 3D RODS WITH L19 BOLTS 4" COLA CRANK MILODON MAIN CAPS AND ALL THE OTHER HAPPY HORSE @#$%
MY CARB PROBLEM IS THAT I WANT TO RUN 1 CARB, BUT I CANT FIND 1 BIG ENOUGH FOR THE MOTOR........SO IT LOOKS LIKE I MIGHT HAVE TO USE 2 CARBS......JUST TRYING TO FIGURE OUT THE SIZE TO USE..........
they only carry an 850 cfm for a blower motor.........but thanks for the search/help.....Quote:
Originally posted by DennyW
Here you go Hot Rod. All you have to do is call them with your engine details, and they will wet flow test it for your setup.
Quote:
Originally posted by techinspector1
At 6 lbs, 6,000 r's, you'll need 1,054 cfm.
THEN WHAT WOULD I NEED @ 9 LBS OF BOOST?
AND HOW DID YOU COME UP WITH THAT DATA/INFO?Quote:
Originally posted by STREET-DREAMS-2
THEN WHAT WOULD I NEED @ 9 LBS OF BOOST?
Looks like the guys have given some good info on this subject. Suggest you contact a reputable engine builder for recommendations. Typically, a street driven blower motor will perform much better with smaller carbs.. two 650 double pumpers set up for a blower should be close to what you are looking for. Remember, 10 to 12 lbs of boost with 8:1 slugs will require race fuel only...been there done that & 3 to 4 mpg @ $4.00/gallon isn't much fun. The cam you are running will also be a huge factor in carb selection. Im currently rebuilding the 55 for street use only (pump gas) ..the 502 with an 8-71 straight up & moderate blower cam should be very happy with a pair of prepped 750's.
If you are spending this much time and money on this project you can afford to skip past educated guesses and goto the #1 carb shop in racing today. Call Pro-Systems and see what they can do for you. They are (arguably :]) the #1 race carb company going at the current time. I run a Pro-Systems dominator...they make great carbs!
http://www.pro-system.com/
thanks for the info...Quote:
Originally posted by larry0071
If you are spending this much time and money on this project you can afford to skip past educated guesses and goto the #1 carb shop in racing today. Call Pro-Systems and see what they can do for you. They are (arguably :]) the #1 race carb company going at the current time. I run a Pro-Systems dominator...they make great carbs!
http://www.pro-system.com/
Have you considered an E.F.I. set-up? It's a little spendy but very reliable once dialed in.Quote:
Originally posted by STREET-DREAMS-2
thanks for the info...
Quote:
Originally posted by STREET-DREAMS-2
thanks for the info...
I THOUGHT ABOUT IT BUT I'M NOT SURE WHAT SIZE TO USE? I THOUGHT ABOUT USING A 100 SHOT OF JUICE....I NEED ALL THE SPEED AND POWER I CAN GET....I'VE GOT A FRIEND THAT HAS A LITTLE HONDA CIVIC HATCH BACK THAT PUTS OUT OVER 500 HP.... I HAVE TO BEAT!!!!!!
if hes going to put 12 lbs boost and 100 SHOT OF JUICE he should consider wings cause its gonna fly. :LOL: :LOL:Quote:
Originally posted by pro70z28
Have you considered an E.F.I. set-up? It's a little spendy but very reliable once dialed in.
I ONLY BUILT THIS CAR TO DO 1 THING AND 1 THING ONLY AND THATS TO GO FAST .I LOVE THE RUSH......Quote:
Originally posted by STREET-DREAMS-2
I THOUGHT ABOUT IT BUT I'M NOT SURE WHAT SIZE TO USE? I THOUGHT ABOUT USING A 100 SHOT OF JUICE....I NEED ALL THE SPEED AND POWER I CAN GET....I'VE GOT A FRIEND THAT HAS A LITTLE HONDA CIVIC HATCH BACK THAT PUTS OUT OVER 500 HP.... I HAVE TO BEAT!!!!!!
you gonna go fast, i just dont know how long. :HMMM:Quote:
Originally posted by STREET-DREAMS-2
I ONLY BUILT THIS CAR TO DO 1 THING AND 1 THING ONLY AND THATS TO GO FAST .I LOVE THE RUSH......
Quote:
Originally posted by lt1s10
you gonna go fast, i just dont know how long. :HMMM:
I'VE GOT A SPARE 434 STROKER BLOCK......ANYWAY ....I KNOW THIS MOTOR CAN HANDLE A 100 SHOT.......I'M NOT TRIGGER HAPPY WITH THE JUICE....I NEED TO BREAK INTO THE 10S.....
look at my pic the pont. drag car has a 350 stock motor, wt. 3000 lbs. shift at 5000 rpms with 4 lbs of boost turn 10.9 all day long. you dont need nothing to go with that blower it will break everything you put in it.:cool:Quote:
Originally posted by STREET-DREAMS-2
I'VE GOT A SPARE 434 STROKER BLOCK......ANYWAY ....I KNOW THIS MOTOR CAN HANDLE A 100 SHOT.......I'M NOT TRIGGER HAPPY WITH THE JUICE....I NEED TO BREAK INTO THE 10S.....
Quote:
Originally posted by STREET-DREAMS-2
I'VE GOT A SPARE 434 STROKER BLOCK......ANYWAY ....I KNOW THIS MOTOR CAN HANDLE A 100 SHOT.......I'M NOT TRIGGER HAPPY WITH THE JUICE....I NEED TO BREAK INTO THE 10S.....
WHAT WERE YOUR YOUR 60 FOOT TIMES?
I DONT KNOW WHAT TO EXPECT WITH THIS NEW MOTOR/SET UP......I'M USE TO A STOCK 355 WITH 7LBS OF BOOST. THAT RAN 11.80@115 MPH......IN A 3000 LBS CAR WITH 26X12.5X15 INCH TIRE....SO I GUESS I'LL SEE IN THE NEXT COUPLE OF WEEKS.....
Quote:
Originally posted by STREET-DREAMS-2
WHAT WERE YOUR YOUR 60 FOOT TIMES?
I DONT KNOW WHAT TO EXPECT WITH THIS NEW MOTOR/SET UP......I'M USE TO A STOCK 355 WITH 7LBS OF BOOST. THAT RAN 11.80@115 MPH......IN A 3000 LBS CAR WITH 26X12.5X15 INCH TIRE....SO I GUESS I'LL SEE IN THE NEXT COUPLE OF WEEKS.....
done forgot about the 60 ft., but you should have run a little better than 11.8. on the carb i ran 2 prediators and i think they made the dif. because they give you what you need and you dont have to guess. thats the only way i got max. out of the blower. look at the pic close youll see the carb. :cool:
had a 4.10 gear with 33" tall tires, no stall conv. keep the blow pulling or dont turn so many rps that you suse up the blower.
Quote:
Originally posted by lt1s10
done forgot about the 60 ft., but you should have run a little better than 11.8. on the carb i ran 2 prediators and i think they made the dif. because they give you what you need and you dont have to guess. thats the only way i got max. out of the blower. look at the pic close youll see the carb. :cool:
had a 4.10 gear with 33" tall tires, no stall conv. keep the blow pulling or dont turn so many rps that you suse up the blower.
so you mean to tell me BONE STOCK MOTOR......no mods...how much did you pay for the carbs and what size were they?
????Quote:
Originally posted by STREET-DREAMS-2
so you mean to tell me BONE STOCK MOTOR......no mods...how much did you pay for the carbs and what size were they?
hyd lifters, stock rocker arms, shift at 5000 rpms. what ever racing predators cost 10 yrs ago. about 300.00, i had 2 on it but one is all i needed. it ran the same speed with 1 as it did with 2. **)Quote:
Originally posted by STREET-DREAMS-2
????