After help on this board about the HP950, I called Holley tech about the actual flow on the CFM. I explained that I have a Holley 850DP which did not give enough low end response but that I did not want to sacrafice horsepower on the upper end and heard that the HP950 was good from idle to WOT. I told them my setup which is:
468
approximately 500 HP
Rectangular GM 990 heads
Full hydraulic Roller setup Lift .595/.612 Duration 242/252
Edelbrock RPM air gap
10.5 to 1 forged pistons
4 speed
4.11 rear
The told the tech that I heard the HP950 flows at 830 and that is the carb I was going to get. He said that I will have WORSE low and mid range response than the 850DP and that I should get the HP750 which will give me good low and mid but less upper power.
Anyway, I need to know from those who have used either. Based on the above specs and two carbs they suggest, which one would you get if you were me (be glad you arent me)
Thanks

950HP would be my choice,,,heck I made that choice a couple years ago. I love the carburetor,crisp throttle response outta da box smile.gif

I would also lean more towards the 950HP as well. I went from a 750DP to the 950HP and I could not believe how crisp the 950HP felt right out of the box. Razor sharp throttle response on this small block.

Most appreciated guys, then the 950HP it will be, now to decide if I should go with the Holley or Allstate that uses the Holley HP950 parts but uses different jetting. They claim Holley uses 78 prim and 78 secon and their Holley HP950 is 78 prim and 88 secondary with jet extentions and no power valve. Thiers is also $100.00 cheaper. Sold on ebay as follows
ANY OPINIONS ON THIS ONE ?
Allstate Holley HP 950 (http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&category=33550&item=2454039635&sspagename=STRK%3AMEBWA%3AIT)

I bought mine from Allstate off ebay. I had a jet kit already so I didn't care what jets were in it. The extensions are nice to have. It also came with holes drilled in the throttle blades which i didn't need, but they are not a problem.

I, too, am very happy with my 950HP. I bought it to replace a 750 VS. Idles very well and good throttle response.

Tim.

Originally posted by 19_chevelle_71:
I would also lean more towards the 950HP as well. I went from a 750DP to the 950HP and I could not believe how crisp the 950HP felt right out of the box. Razor sharp throttle response on this small block. graemlins/thumbsup.gif

Sheesh...

Maby they hired some of the CompCams Tech people :D

Go with the HP950.

I switched from a JET Stage 3 prepped 850 that supposedly flowed around 920cfm :rolleyes: to a HP950. Can't tell you if there were any improvements at the strip, (no track time yet) but just driving around the street, there was a noticable improvement in the throttle response in the low-mid range rpm's. The upper rpm's seem to be just as good as the 850 but again with no track time can't say for sure.

The only issue that I had with the HP950 was it ran VERY rich at idle. I had to have the idle circuits tuned for my application. I have had it on for about a year and a half and have had no problems since. graemlins/thumbsup.gif

Just to suggest a third option; a 1000 HP would also work pretty well on that setup.

This reminds me of a good friend of mine .... Granted his is a 2500 pound race car...with a stout 427 + .060 in it.....He would launch at 7200 RPM and go through the lights at 8400 RPM....Ran a 9.27 et in the 1/4..... his carb.... A Holley 0-4779 750 CFM DP.