Is A 750 hp vacuum secondary good for street strip car?

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PG Duster

PG Duster

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I have a 1974 Duster, with 360 magnum 9.1 compression, EQ cylinder heads with 2.02” in take valves and port job, mild hydraulic roller cam, 727 trans with 3500 stall with 3:91 sure grip 8 3/4 diff. I have a Holley 750 Hp vacuum secondary Carburetor on a Edelbrock air gap rpm intake manifold. Would there be any advantages to buying a double pumper carburetor for better preformance or
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is the combination I have a good one?
 
If its a street car I would prefer a carb with a choke horn.
 
I would rather a choke on a street car, too; but I know a few people that have run without them. I was always taught / read, if it's a street car, go with vacuum secondaries. There are of course exceptions to the rules. Is there something you don't like about your current setup?
 
What is;
PG Duster said:
mild hydraulic roller cam
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Honestly; if that's a streeter, you could run a 2bbl on that combo and hardly know it until third gear, except for the lack of tirespin. Don't believe me? Do some time trials with and without the secondaries working.

It looks like you have built a point and shoot kindof car, so it don't much matter what's on the intake.

At the price of New carbs these days, IMO, you would be disappointed in the minor change.
 
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That's a great carb for a weekend warrior probably not your first pick if it's a daily driver lack of a choke being one reason. But if the car is running right and functioning like it should you're not going to do much better for WOT horsepower
 
My old 440 duster was made to run 11.001 It had a Holley 780 vacuum secondary carb. The new owner put a 750 dp on it. Ran the same times. It’s all in how u tune it. It’s not just a one and done thing. It can be hours for little to no gain. This was strictly a race car. Kim
 
My 69 FB Barracuda was a tenth faster with the 750 DP vs 750 VS which had an adjustable secondary pod. The car launched off the transbrake with the two step set 3200 rpm....
 
70aarcuda said:
My 69 FB Barracuda was a tenth faster with the 750 DP vs 750 VS which had an adjustable secondary pod. The car launched off the transbrake with the two step set 3200 rpm....
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Same jetting ? Was the switch at the track on the same day ?
 
yes......at TnT,,,,,,

The VS 750 secondary blades were not opening while on the transbrake. The launch was much smoother...but a bit slower
 
Sorry about my slow response, I just got back from vacation and I’m catching up with this information. Thanks, you guys
 
royslead said:
I would rather a choke on a street car, too; but I know a few people that have run without them. I was always taught / read, if it's a street car, go with vacuum secondaries. There are of course exceptions to the rules. Is there something you don't like about your current setup?
Click to expand...
 
I haven’t made it to the dragstrip yet, still building the car. Except for the choke it seams to be running great on the street. I will find out once I get to the track to see how it performs.
 
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I like my 870 street avenger vac sec carb very much and use on strip mostly w some street. It has manual choke but rarely use it.
 
I got my car from trans shop, trans shifts great, stall converter launches the car good, the 750 vac sec carb is working good. Our drag strips are closed for the winter, in January I’ll be taking it to the drags. I will borrow a 750 double pumper and compare them at the track, to see which one performs better.
 
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