Holley and Demon opinions?

[Triplet]

Hi all, I am looking for some opinions and information on comparing the BG Speed Demon to standard Holley 4150/4160s.

Background:
I have a 71 Monte, 454, with a small roller cam (226/236 @0.050"), an air gap intake, 9:1 compression, and some decent rectangular port heads. With 3.55 gears, about a 2500rpm stall, and a 750 vacuum secondary holley, it ran a 12.75. I have been wanting to try a double pumper for a long time and thought what the hell, I'll try a Demon. I chose it because I liked how you adjust and tune the Holleys, and the Demon seemed to be a more well thought out Holley with it's smoothed venturi and little details like sight glasses and forged base plate (not that I ever knew anyone who actually broke a base plate), etc. I bought a 750 double pumper Street Demon, but haven't tried it yet---snowy in Missouri right now.

I'm just curious if there are any other people out there who have used both and care to comment on the differences---good or bad, and why you would choose one over the other.

Thanks,
Triplet

[NOVA71]

OK, I've never used a holley 4150/4160 but I will tell you what I do know. My friend bought a new Edelbrock (carter style) carb and could not get it to work like it should on his 350. I do like the Quadrajets. They are usually the best compramise you can get for good performance and fuel milage. I decided to buy a new Holley model 4175 for my Nova. It was a spreadbore style that worked great right out of the box. Ran a bit rich but no big deal. The electric choke was amazing. One pump, turn the key and drive away. It was like I had fuel injection. I bought this style because I thought it would give me half decent fuel milage. Wrong! After a few years I decided another upgrade was in order and this time I picked up a used Speed Demon 650 vaccuum secondary and electric choke that was like new. I've only driven the car once with this carb on it and this is definately the carb I'm going to stick with. It seemed to pull alot harder than with the Holley.

[Triplet]

Well, since apparently nobody else on the forum is using a Holley or Demon carb, I figure I'd give an update. The new 750dp Speed Demon seems to be running great. It was jetted pretty rich, but I'm sure they do that as a safety factor from the factory to keep people from running too lean and burning valves etc. Carb seemed to be decently made other than some accelerator pump arms needing tweaked to line up just right. Unfortunately the race track near me closed down this year so I did not get a chance to run the new engine combination officially, maybe next year. The car definitely feels different with the double pumper, and the throttle is alot harder to push once you hit the secondaries. Overall, the demon is identical to the holley with the difference being billit pieces and the idle-eaze system which has been useless to me--maybe with a larger cam it would be more important.

[MagicRat]

Thank you for the update. I have admired the Demons, as you saym they are Holleys but without the fussy little design short comings, but I have been put off because

1. They are expensive
2. I have boxes full of various Holleys, some were bought new, most were used.

I agree, tuning Holleys is tricky, until you know what you are doing. After that, they are a blessing because they are so tuneable, you can get them to do just about anything.

Every Holley seems to be set up WAY too rich from the factory, which has contributed to the myth that Holleys provide bad gas mileage.
They do - until you set them up right.