what is the minium fuel pump flow to feed two 650 cfm double pumper?

...depends on how much gas the motor is gonna suck outta them. What are they on?

D/W

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If it ain't broke, fix it!

there on .080 over 225/ with 4-71 blower driven 1-1

Damn, that's an oddball combination! Do you really think it can use all that carburetion, even with a huffer?

I've got no experience with blower motors. I can tell you that the good ole high-volume Carter mechanical pump fed my two AFB's on a 440 just fine.

D/W

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If it ain't broke, fix it!

dont know if it to much carb,this is only being raced,the problem is the car is laying over just after i pull 3 gear, as i start lifting the engine starts pulling again, feels like fuel starvation. my pump is 5494 carter electic 72 gal/hrs,just wondering if there is a minium gal/hrs you should have.

Sure sounds like it. Just out of curiosity, what size line are you running?

D/W

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If it ain't broke, fix it!

3/8 copper all through with large fittingson bowls with duel inlets

Don't remember where, but I stumbled on a web site that had a calculator to figure it out................

It had something to do whith brake specific fuel consumption

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Terry,

72 gal/hr, or about 400 lbs/hr sounds like it should be plenty. What trap speeds do you get (or should get) in the 1/4 and what does your car weigh? You can support something like 600HP with that fuel flow.

650 carb is not too big for that setup, IMHO.

So, I don't think the fuel supply is the problem, assuming it's working properly. Seems like carb would be next to look at.

Lou

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Home of Slant6-powered fun machines since 1988

Lou, my understanding is that he's running two.

D/W

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If it ain't broke, fix it!

Ah, that is a lot of carb.

I still think the pump should source plenty of fuel. I personally would not want to get two 650 carbs working on any Slant, but I'm sure it can be done. A single 650 is enough to get you into the 11s in a 2800lb car. Mike J is running high 11s with a single 600, NA on gasoline.

Lou

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Home of Slant6-powered fun machines since 1988

hello agian had to work so missed your debate, this is a combination i settle because i had the parts. last year i ran a small blower on the same engine with a 750cfm and 5lbs of boost at 12.30ets/109mphs.this bigger 4-71 blower is running 12.20/93mph but thats is while i am lifting in 3rd gear ,if i stay in the throttle the full 1/4 the car slows and shows signs of detonation when you pull the plugs.

Car laying over in high and picking up when you let off is a classic sign of overcarburetion.

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Official Cookie and Mater Tormentor.

thanks, so if i stay with 2-4 vac/secondary would be a better choice

It seems to me that your single 750 would be the best choice. A single 750 is good for at least 400HP and you are definitely not close to that range yet. 2 vac secondary carbs would work, but it seems overly complicated to me.

Lou

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Home of Slant6-powered fun machines since 1988