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I'll be in the market for a new 4bbl in the near future. I was initially thinking a 600cfm-ish Holley DP or Demon for my basically stock 289,jetting down a bit until I opt for a new cam and heads.

But, I can get a decent deal on Holley Street Avengers through one of my brother's vendors.

I'd like some reviews from folks that have/had them. How do they run/tune, etc.?

Thanks,
 

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I have a street avenger carb, 770.
It was jetted a little high out of the box, but simply jetting down and it runs (ran :() like a champ. The only screw adjusted on it was the idle screw. No float levels out of whack, secondaries seemed to open up right at the correct time, etc...

I like the carb and I am pretty happy with it for the 500 miles I've run it.
 

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Have a 670 Avenger on my 66 302 with 15 minutes run time . Can't wait to really romp on it .
 

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I got a deal on a 670 used and it had been previously messed with. The PO had the choke jerryrigged open and god knows what else. We took it apart and checked everything and put it back together. It fired right up and I am pretty happy with it. WAY noticeable difference over the 600cfm carter/edelbrock I had on before. I just got a jet kit and some assorted parts and manuals for it IO'm going to tear into it again to try and get it optimum. if I had to buy one for full price right now it would be a 625 road demon or roqad demon jr for a mild engine or a 650 or 750 speed demon with mechanical secondaries for a modified engine. good luck.
 

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I've got the 670 on my car. Took it out of the box, bolted it on, adjusted the idle and haven't touched it since. Though it's supposed to be very tuneable, I haven't had the need to mess with it yet. Overall it was a massive improvement over the very leaky double pump I had on the car before.
 

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When you say a "noticable" difference....in what way exactly?
 

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Also have a 670 on my 302. It's nothing short of incredible. Like the others have said, you take it out of the box, adjust the idle, fast idle, and you're on your way. I thought the 670 would be too much for my pretty mild engine (performer intake, headers) but it has never bogged. And now I have room to grow. I say go for it! Holley really got it right with this one..

Dan
 

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Running Street Avenger 670 on mine.... No problems to speak of, but I think I'm a little rich on the primary idle so need to try jetting down. Other than that it's been very good to me and easy to adjust :)

Ken
 

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Have 570 cfm Street Avenger on my 5.0L HO (GT40Y/E303). Now that its in tune it runs fine, looks good. Great low end torque on low rise Weiand and good to about 5500 rpm (fine for me). Here's some comments:

a. Electric choke performance. Works well but comes off too fast in cold weather compared to thermal choke. Fine in warm weather.

b. No fast idle adjustment. Fast idle cam is fixed. Idles about 2000 rpm which IMO is too fast for cold start. Steps down nicely though.

c. Although Holley advertizes it runs right out of the box (it does), it still requires some tuning. Mine required float setting (way out) and mixture setting (close but not at max vaccuum/rpm). Vacuum secondaries worked flawlessly out of the box.

Bottom line? Good carb! Like the fact that its got all the ports needed for any early application (Brake, PCV, ported vaccuum, unported vaccuum). Doesn't need a dashpot in my experience.
 

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670 here also on my 302. It was on the car when I got it. Holley sent me the manual for free, made a few adjustments on my own using the manual (no previous experince) and now it runs great.
 
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