The Guy in MY 99TA

I have a 68 camaro, w/ a th350, 3500 stall, 373's and some 26-10.5's out back.

I have a 383 built my meself. It consists of an eagle crank, scat 5.7 rods, srp flat tops, a comp XR-286R(248/252 @ .050 with .576/.584), topped off with a set of Brodix Track-1's(out of the box), and on top of that sits a Victor Jr. intake(gasket matched) and currently a rather small Holley 700 dp. I am working on getting either a complete MSD ignition or maybe a DUI distributor and the rest msd stuff. I am not very sure on the ignition yet and I'm using stock stuff now. All that flows out of the engine through a set of Hedman 1 and 7/8s headers.

I was wondering what size carb you guys think would be suffiecent. I was pondering into something like a Speed Demon 750 or a 825. I think a 750 might not be quiet enough but I think an 825 might be a little much. I could go with a Holley 800 DP but I just want to try something different(i'm not one of those people who don't use holleys I just want to be different for a change). I have heard some really great things about the Demon carbs and would like to try one.

Josh S.

The Guy in MY 99TA

FWIW the car doesn't or hasn't seen any track time yet and probably won't see very much in the future. I am trying to get into restoring the rest of the car and won't be long before I start puting the stock 327 and glide back together.

Josh S.

02WS6Bird

iTrader: (2)

my buddy's uncles gotta 455 in his chevelle still running a Holley 750 carb...hes probably going 850 4 barrel but would prefer to actually be able to MAKE IT to the gas station

and ive seen some 396's actually alot with 750 carbs...so my .02 would be jsut go 750

EDIT: 454

The Guy in MY 99TA

Well what ya have to look at is what those engines had done to them. I have seen big blocks sporting 650 holleys.

what you would have to use to compare them would be a big block with aluminum heads, a medium sized roller cam and other things. A big block built similair(or by comparing the parts and making an equivilant should make around 650 hp)

From the engine builders I have talked to this engine should make over 500 hp at the flywheel.

Josh S.

xxx

Go with the Demon 825...

I had good luck with my 1190 demon on my 540. Believe it or not it had pretty dern good street manners for such a big azz carb.

68maro

just throw a 1050 dominator on it and jet it about 88 to 91 square and never look back you'll love it. you'd be amazed at how well they work. had a 850 on a buddies 383 in a vega ran consistent 11.15's did no change but an out of the box dominator and the car now runs consistent 10.70's with better street manners a better idle and crisper throttle response. while another friend has 1 on his 9.8.1 cr 406 runs 10.50's to 10.60's or you can put pump gas in it and drive around town all day. got an 1150 on mine and love it. best carburetor on the market and don't be scared it will be fine with good tuning

Race Car Driver

Don't rely on a poll of us amatuers, call Brad at Dream Chaser racing engies and ask him, (806) 371-7288. He's been building SBC and BBCs and Pro Stock motors for over 30 years.

The Guy in MY 99TA

I could call Barry Grant himself and I will when I finally figure out what I am gunna do. I was just wondering what other people think. I know I could go really big and just jet down but I'de rather go just a little bit bigger and have a little room to work with rather than a mile or 2 to work with. I do NOT want to go too small but I beleive anything more than an 850 might be a little much or might be just enough b/c the engine should make over 500 fwhp(desktop dyno says 545 and a couple local engine builders-- very reputable also say that 525 or 530 could be there).

Josh S.

Josh S.

Villain281H

iTrader: (5)

I'm running a somwwhat similar combo to yours in my Nova. Eagle crank and rods, canfield aluminum 195 cc heads 2.05/1.60 valves, crane 518/536 240/248 duration solid cam, victor jr intake, 1-3/4 hedman headers and full 3" flowmaster exhaust. At the beginning of the year I ran the time in my sig with a 650 dp holley, but since then swapped to a 750 hp holley ($600 but worth it, very little changes to it, none of which involved jetting) and picked up a tenth and almost 7 rwhp at peak. I wouldn't think you'd need more than a 750 dp or hp, as my buddy runs a speed shop and has a 3400 lb 71 nova with a 496 that makes 475 rwhp and runs 10.40s with a 750 dp (been worked a little, but nothing the knowledgable guy couldn't do). He's tried multiple carbs on the dyno and the track but the 750 works best and still drives on the street very well. Demons are nice but not many people I know run em. I'd get a 750 hp holley dp.

Derek

The Guy in MY 99TA

See that what i dun get........ some people can run 750's on big blocks and nothing else will even perform with a 750 but then some people can put a 750 on an engine and it will starve for fuel. I know its all in the tuner of coarse but there should be a median. I love holley products I just want to try something different.

Josh S.

Ls1LikeNoOther

Run a Quick Fuel 850 and outta the box it will be amazing but it has incredible adjustability!

Race Car Driver

Well, if you just want to know what people here recommend, try a Holley 850, put it on an engine dyno, and find the right timing, jet and air bleed setup.

We dyno'd my dual 1150 setup last week and I saw a huge variation in hp depending on the factors such as jet sizes. Don't guess, dyno it.

slow trap

iTrader: (22)

my bud has almost your exact combo accept dart 215s.had a holley 750 dp=ran 7.40s at 94-95.switched to speed demon and started running 7.20s at 96-97 mph.throttle response is much better also.you will have to do some fine tuning tho,drilled squirters and such.

Race Car Driver

Oh I agree, one degree of timing +/-, or one jet size, or one air bleed, or a 2 1/4" header primary versus a 2 3/8" primary can have big impact on hp and torque.

bad2000ss

iTrader: (6)

I have run and Edelbrock 750, Holley 750 DP, and Demon 750 Vac Sec on my truck and by far the Demon made the best power of the three with the best throttle response.

The problem I had with the demon was the constant maintnance. This truck has been my daily work and back car for the last three years and for the year I had the demon on the motor I replaced 3 sets of Air/Fuel screw adj seals, and redid the floats twice on top of two complete rebuilds.

The primary float would stick and flood the motor more times than I could count. (Embarassing on a busy street corner when everyone hits the dirt when it would back fire then stall. I couldn't make a fast get-away, I had to pull over and pull it apart. I used to keep the Allen wrenches in the glove compartment it happened so often.)

Then the idle air/fuel screw seals would gunk up quick and cause a vacuum leak. After fighting with the Demon for almost a year, I decided to rebuild once last time and sold it.

The only problem I had with the Holley was the 6 miles to the gallon I got after I installed it.

In the end, I went back to the Edelbrock because if anything, it was consistant for my purposes. I used to curse the Edelbrock carb after I put in the Demon. After realizing the Demon was almost as high maintnace as my sponge girlfriend at the time, I was happy to have the Edelbrock back.

IMHO the Demon is a great carb for race/drag car or something that is driven very little, but deffinately not for anything you want to drive on a daily basis.