650 speed demon vs 700 holley dp

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1970 La

1970 La

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Hey guys I am looking for some input on the 650 speed demon carb with vac secondaries. I have a 700 holley dp that I am sure is going to end up on this engine before it is over with.

The engine is a .030 340 with 11.1 compression. Has stock unported J heads and 1.88 intake valves and a victor 340 intake. Camshaft is a bullet 252 intake 253 exhaust @ .050 with .516 lift solid flat tappet and 108 lobe seperation. Cam is in @ 106. Will be running a four speed and 4.30 gears. 1 7/8 hooker headers and 2 1/2 exhaust. The car is a dodge dart.

This will be street drivin at times and raced also.

So what do you think the demon or the holley?

Is it true that demon carbs flow more than advertised?

Any problems with tunning the demon?

If I left out anything out as far as combo let me know thanks.
 
Check Demon specs and see if it will work with your cam specs. like over *** duration needs a race demon, etc. Its should still be available somewhere. Demons are wet flow rated just like Holleys, that is a myth. Bob, FBO (4secondsflat.com) used to sell Demon but are now a quickfuel dealer, Bob is still the man when it comes to Demon carbs.
 
To be honest this is the response I was expecting. It seems like several years ago alot of people were buying Demons now nobody wants one. It is very hard to beat the holley. At least three of my double pumpers are 10 years old or older and they still work great. Thanks for the replies!
 
I'd run the Holley and single plane manifolds should always have 2 accelerator pumps. A vaccum secondary carb on a single plane is a bad plan.
 
As far as the BG vs Holley the absolute best carb I own is an old(built by Barry hisself) 1000cfm unit. Of course many production BG's were garbage.
 
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