Which Holley?

[pbrown]

I was originally planning on using a Speed Demon 650 DP carb. What would be the equivilant Holley if I went that way?

Thanks,
Pat

[JAM1775]

The new Holley Avenger series carbs seem closest to the Speed Demons. Another Holley carb for higher end performance is the 650 HP series. The HP's are very good race carbs. But I am a Demon fan myself !

[pbrown]

The Avenger is a vaccuum secondary setup. I'm looking for mechanical secondaries. How does the Holley HP 4150 (650CFM) compare to the Speed Demon w/ mechanical secondaries?

Thanks,
Pat

[Jack21]

For a 393W in a Cobra, suggest the 750 DP in Holley or Demon. Leaning toward Demon as they seem to work better, and are less touchy. Definately a double pumper for instant throttle response.

I have a Holley 700 DP on a 351. Power is "Right Now" when I crack secondaries in any lower gear.

For a 4000 pound sedan, 350 - 400 ci size engine, auto trans, 3.08 gears. Go vacuum secondaries or the engine will bog.

[Andy Dunn]

There are a few Holley 650s to choose from (with mechanical secondaries)

0-4777C
chromate dip finish / mech choke
http://www.holley.com/HiOctn/ProdLin...C/0-4777C.html

0-4777S
shiny / mech choke
http://www.holley.com/HiOctn/ProdLin...C/0-4777S.html

0-80777
choke / braided fuel line
http://www.holley.com/HiOctn/ProdLin...C/0-80777.html

0-80542-1
race ready out of the box / 30cc
http://www.holley.com/HiOctn/ProdLin...0-80542-1.html

0-80541-1
race ready out of the box / 50cc
http://www.holley.com/HiOctn/ProdLin...0-80541-1.html


Personally I like the race ready units and think the 30cc unit would be sweet

0-80542-1


The race ready units are really well made but they come at a premium price. This unit sells for $589 at RACESEARCH.COM and $582 at Jegs.com

http://www.racesearch.com/CGI/racese...iption_id=1685


If you decide to go 750, you might consider
http://www.holley.com/HiOctn/ProdLin...0-80528-1.html


hope this info is useful

Andy
http://www.cobralads.com

[pbrown]

Thanks everyone for the info. I still havn't fully decided on which carb. I think the 650CFM will be good for the mostly street driving I have planned. I like the speed Demon 650 and just wanted to get an idea of which Holley would be comperable. I have some time to decide. Perhaps I'll buy that 351 weber setup on Ebay.

--Pat

[JAM1775]

My friend has a 650 Speed Demon on his new 392 stroker from FMS. He loves it. I agree that mechanical DP is the way to go hands down. I am running the 650 Race Demon on my 450hp 351W and I love it. The Demons wet flow above 700 cfm . You will not need more than that for the street. At WOT the mid-range to 6000 rpm will snap you back. My chip is set at 6200 ...peak HP at 6000 with the 650 Race Demon. You should not need much more air flow than @ 6200....and we really only visit that rpm for a brief moment.