BLKMGK Posted May 25, 2001 Share Posted May 25, 2001 We've discussed this some in the past, I'm still on the fence. Price difference between a Holley "Avenger" and the Speed Demons is all of $20 or so. I've pretty much ruled out Edelbrock carbs due to their renowned return rates etc. but I guess if there's enough support maybe I'd change my mind. Price is certainly right for those suckers but even friends of mine locally are warning me away from them - I wouldn't know where to start to tune them. Anyway, I know Mike had trouble with his Demon, Mike did you ever work it all out? It looks like replacement parts, at least in the catalogs, aren't falling out of trees for these. Can they accept Holley jets etc.? Difficult to tune? The idea of a design that's been cleaned up and refined appeals to me but not if parts are hard to find. I'd prefer to do little tuning if I can help it and hope that the design is close enough to a Holley that finding help won't be hard if I needed it. Tips or tricks for the Demons I should know about? Holley on the other hand is an old standby. The new carbs certainly sound like they've got all the features you'd want. I hear the silver plating comes right off if you hit them with solvent though - not exactly the billet parts used in the Demon. Has anyone used one of the Avengers yet? I actually went after a carb or two on E-bay but am wary about spending very much since it'll probably turn out to be a carb that's WAY out of tune or in dire need of a rebuild right off the bat. I'd like plug and play as much as possible! I happen to hate carbs but to get this puppy running that's what I'm going with - EFI later. Tuning I'd like to stay away from if possible and will accept slightly less than optimal performance if I must. If it doesn't bog I'll leave it alone Lastly, carb sizing. I expect between 425-450 horse. Holley rep at the track told my friend I ought to be looking at a 650 for street use in my car. Jeg's catalog for the Avenger claims that carb is good to just 400HP. The 750 is for 400+. Corresponded with someone who has a 650 on a 383 that sounds much like mine and he's selling it for a 750. Seems on the top end the car feels starved for air. I've looked at Holley 700's but they don't sound like they come as tricked out as the Avenger series. They're also apparently manual secondary only "double pumpers". Edelbrock and Demon don't appear to have 700's available. Spoke to a friend with a Holley 650 on a 406, he loves it. Doh! I hate conflicting information.... P.S. Have read some of the old threads on Demons, not many there but not much good said either. Holly's "interactive" product selector doesn't ask many questions but points to the Avenger 750.. [ May 25, 2001: Message edited by: BLKMGK ] Quote Link to comment Share on other sites More sharing options...
Andrew Bayley Posted May 25, 2001 Share Posted May 25, 2001 I'm running a Holley 650 double pumper in my 350 at around 6400 rpm's. I've gone through and dialed everything in to "supposedly raise the CFM up to 680. But even before I did that, the 650 worked well. The only real problem I had was that the float bowls stuck on me a couple times when I first bought the unit. I guess it's a good idea to pull of the bowls and manually move the floats up and down a few hundred times to break in the needle and seat. Once I did that, I never had a problem with sticking floats (knock on wood). I don't think any more than a 650 is really necessary on a 383. Yeah, you might see a couple more Hp out of a 700, but it's more than likely not worth the extra $$$. A fellow co-worker runs a 383 at 7000 rpm on a 650 double pumper. However, another co-worker runs 6200 rpm on a 350 with a 750 vacuum secondary Holley. I think it's all preference and appearance. I don't think you will see much difference between a 650 and 700. As for the Demon vs. Holley, it was a no brainer for me. I used to work for the old Holley OEM division (now Borg Warner) so Holley parts were everywhere. Also, there were enough old timers still around that knew how to get the most out of my carb. When I looked into the demon's, they were basically the same thing as a tricked out Holley. Down leg boosters, four corner idle, etc... Either one would probably perform about the same. I'm sticking with Holley though, because of the parts availability and common knowledge people around here have of them. Heck, last year at the track I blew out my power valve (timing slipped back 15 degree... oops, should have tightened that distributor down!!!) and within five minutes I had found three separate people with replacement valves. Good luck, -Andy Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted May 25, 2001 Share Posted May 25, 2001 Yeah I agree, the parts availabilty alone is what makes the Holley attractive. Any Kragen, Autozone, Pep boys etc has parts (although don't lose a float bowl sight plug cause you won't find one at those places.... I dropped mine, but luckily I later found it..). Size wise, probably 650 would be sufficient, but you probably could get away with a 750 and not suffer any ill effects and maybe a few horses on top. The Demon's definately look tricker but look like basically a cnc billet Holley. The billet won't do anything over cast performance wise. I have the new bright zinc on my holley and had I to do over probably would have just got the old gold holley. The bright work is not that impressive and looks like its going to dull for sure. Regards, Lone [ May 25, 2001: Message edited by: lonehdrider ] Quote Link to comment Share on other sites More sharing options...
pparaska Posted May 25, 2001 Share Posted May 25, 2001 Here's my take on it, surely not everyone will agree, just the way I see street carb usage: I'd do a Holley, since that's what everyone seems to know and have parts for. The Quadrajet and Carter are great, but tuning is different, and less well known to many and they're parts aren't as prevalent. On the street, with a less than huge cam, I think vac secondaries is the ONLY way to go. If you're building it for stoplight or strip racing, double pumpers are probably (not always) better. For that reason, I think a 750 vac secondary is fine - you're only running on half of it until the diaphram/spring lets the other barrels open, so "Too Big" really doesn't apply, as the flow through the two primary bores is plenty to get a good signal to the venturis. The 3310 model (750 vac secondary) is very well known and there are dozens of articles on how to tune them. The Avenger is based on the 3310. Double Pumpers are really not very appropriate for around town driving. Bog is a concern if you put the foot into it too far (although this is somewhat adjustable with linkage). The Vac secondaries take care of the Bog factor, once the right spring is installed (get a spring assortment and a quick change cover - the Avenger has it already). Well those are my opinions anyway. Someday this will all be for naught and I'll have EFI installed. I drool over the Commander 950 ad everytime I flip past it in the catalogs! Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted May 25, 2001 Author Share Posted May 25, 2001 I do think I really want a vacuum secondary. Pete's got a point about only running 2 barrels until the hammer comes down. I also only intend to run this until I am happy enough with everything to tear it down for EFI I've been looking at Force EFI and drooling! http://force-efi.com/ After I posted I hunted around some for Demon info too. Much of what I read echoed what's above - especially parts availability. Guess I'll be going for the tricked out Avenger. I'm not thrilled with the shiny stuff but things like the quick change secondary spring, site plugs, "protected" power valve etc. seem to make it a good purchase. As always, thanks! This project is almost there, or so I keep telling myself. If wheels came today that will be a big step. Cut a hole in one of my valve covers yesterday for the filler - that was scary! PCV coming soon.. Quote Link to comment Share on other sites More sharing options...
Mikelly Posted May 25, 2001 Share Posted May 25, 2001 The BG is probably as close to a "RACE" carb as you can get out of the box, which is good and bad... <Good if you know carb theory and setup, bad if you don't. My car was tuned by a pro and I went out and ran 10.98s on it. I tuned it about 6 months later and I couldn't run in the 11s... Bottom line here is if the carb isn't tuned properly, ANY CARB, it won't provide you with the service you need... Jim, based on Petes Desk Top Dyno Numbers, and based on a few articles I read on carbs, I'd go with the 650 for now, since it isn't a final purchase for you. I also wouldn't think twice about buying an edelbrock or a carter, as my opinion is that they are perfect, simple and reliable out of the box. Here is one thing I learned from a buddy of mine who used to work at pep boys...reason some edelbrocks have a return rate is that the major chains stock reman units... for a while their reman service was lacking. My Brother inlaw to be has 3 Carters and has had no problems at all, and my neighbor runs two carters on his blown 55chevy... Again, no problems at all... They are easier to get back to a baseline tune if you have little or no carb experience.. their manual is also superior to other product manuals I have seen. I'd go with an edelbrock for ease of tuning, but knowing that you wouldn't get that extra 2HP that you might from a holley based carb unit... Mike [ May 25, 2001: Message edited by: Mikelly ] Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted May 27, 2001 Author Share Posted May 27, 2001 Heh, well I found a 770 Avenger on E-bay A couple of them actually and they're cheaper than Jeg's so we'll see how it goes. Every source I check online including Holly seems to point to the bigger carb. I guess under carbing it a hair wouldn't kill me though. IF I can get the 770 I will. A 670 is an option and yeah I'm considering that too. This isn't the final induction setup but looking aorund it's not going to be cheap to go EFI, I might have to hold off a bit. I want to actually drive this car some and tearing it down right after getting it running would kill me. I made some progress today parts chasing and getting my oil fill welded in. The oil fill was a goat rope but it's in there and I've "restored" the threads (shiver). As for Edelbrock - the folks who will tune this puppy will know Holleys best. Heck, shake a tree around here and someone who knows Holleys falls out. Show them a different carb and they seem to glaze over We'll see. I hate this! Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted May 27, 2001 Author Share Posted May 27, 2001 Well, seems I've got a carb! NO one bid against me which gives me a little queasy feeling but I saved about $50 over buying it through JEG'S so I'm not bitching It's a 770CFM Avenger Holley. If it proves too much there are plenty of used 650's out there I'm finding on E-bay that would need to be rebuilt. (shrug). I do have one STUPID question. My Victor Jr. is listed as having a "4150 style flange" - I'm only just now noticing this. Will the Avenger series carbs fit this flange?! I was told NOT to buy a 4150 carb since they were mostly race oriented but now I'm wondering if I've shot myself in the foot here? Have I mentioned lately that I really like EFI? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted May 27, 2001 Share Posted May 27, 2001 stock holley or Demon: DEMON holley HP or Demon: HOLLEY HP Quote Link to comment Share on other sites More sharing options...
Mikelly Posted May 28, 2001 Share Posted May 28, 2001 Hey Jim...I can get Victor JR. style Holley intakes pre-drilled and welded with injector bungs for less than $300! Makes you want to run out and sell yours doesn't it??? You know, if you went EFI right now, you would be ahead of the curve.... Mike Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted May 29, 2001 Author Share Posted May 29, 2001 It's on it's way. I'll let everyone know how it works out. Where are Victors predrilled for $300? With fuel rails and mounts? Throttle bodies aren't cheap though and neither are injectors although I can get deals on those. Some of the Mustang Spyder setups use a 90 degree bend bolted to the carb mount with a normal Mustang TB bolted on... I'm a long ways from an EFI setup though. I did see that Whipple is supposedly putting out a nice ECU that may be MAF capable. Hrm! Quote Link to comment Share on other sites More sharing options...
Guest needwaymorespeed Posted May 29, 2001 Share Posted May 29, 2001 My vote is for cartsrs they are very easy to tune no power valves to blow out and a 2 piece design every car ive put them on has run better and gotten better fuel mileage than the holley series,but then again thats a comparison of a holley mechanical double pump versus the carters vaccume style secondaires-anothe nice thig about crters is there secondarie throttle plates are counterweighted vrss the 3310 cvacume diaphraghm-just one less thing to go. I even had a carb shops stage three holley at one point on a big block car the holley outperformed on the top end but i got only 6 mpg with it vss 9 with the carter I could give up the .08 sec difference in the quarter for the mileage. Having said all this, Im guilty of buying mikes old carb so I hope I can get it to run well, Holleys and the copycats of holleys are just alot more sexy than a Carter Curtis Quote Link to comment Share on other sites More sharing options...
pparaska Posted May 29, 2001 Share Posted May 29, 2001 Mike, I think we need to talk. That Vic Jr. I'm getting from you may get a few injector bungs in it... Who does this cheap? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted June 4, 2001 Share Posted June 4, 2001 Figured I'd post in this thread, since it's kinda similar.. I saw a TV ad for the Holley Street Avengers this weekend, they look to be a good street/some strip setup... I'll be building my Z to be a VERY enjoyable fun car, with occasional trips to the strip and maybe the track for kicks... Whaddya think? Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted June 5, 2001 Author Share Posted June 5, 2001 I picked up an Avenger off of E-Bay at about $40 less than Jegs. I've NOT run it yet but it does seem to have all thr tricks already done to it. We'll see! Quote Link to comment Share on other sites More sharing options...
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