wasup ,I have a 1969 307 witch is 30 over has performer intake,bracket racing cam ,headers,heads have been ported ,pete jakson timing gears,all the basic performance add ons ,I have a carter afb performance series carb on it and it just dosent respond like i think it should,remembering this is the 200hp block when stock.
What size carb would be approperate for this set up?this is set in a 87 firebird /trbo400 posi get r dun  

Welcome to the forums, can anyone help chris30.  

What's the specs on the cam? What's the comp. ratio? What heads do you have? Gear drives are about the worst thing for transfering harmonics.  

the cam is 250/260 - .532/.555 and the heads are 64cc 215/85cc-2.08/1.60 max lift .650 and compression is 9.0:1 and yes i agree with the gear drive comment but i love the noise  

That cam is way long for anything besides a full tilt race engine, with at least 12:1.1 comp. ratio. The soccer-mom mobiles will smoke you with the way that thing must be running. 9:1.1 comp.ratio isn't going to cover the cylinder pressure loss. 250-260 dur@.050 has the powerband in the 4000-7500rpm. range! There is no way it will respond like it should. A cam for the street, with 9:1.1 ratio, should be in the range of 225-230dur@.050, and no more. This spec. would put powerband in the 1500-6000rpm range.with decent low end and a strong mid and top end. Of coarse a roller cam can get the valve lift, your set-up is capable of, and keep dur.@.050 where it needs to be. You did not say what intended use was, so I assume it's a street car and will need a 2500rpm stall converter to make use of my cam pick. Always carbuerate as small as is required to satisfy the engine demands. In your case, after installing a suitable cam, I would start with a 650cfm.  

this is for mid to top end use,high spped no street use,power band 3000+ my prob is no emph at mid rpm ,rong compression ratio ill have to change that to 12:1.1 will that be more on the right track  

ps this block has sleeves aftermaket internals ext work has been done to allow optimal oiling so it should handle the change thanks  

My mistake about the intended use. The intake manifold pick had me thinking street. That manifold will not flow past 5000, maybe 5500rpm. Your going to need an open plenum to spin high rpm. If you can give me the intake closing point, I can give you a ballpark comp. ratio. If you can give me, piston to deck height, head gasket volume, and I assume stock length rods, as well as intake closing point, I can give you a near perfect figure.  

the intake is a edlbrok victor edl-2900# wich is cnc ported it is a single plane manifold good for 3500-8500 rpm,cant rember exact piston to deck height but i know it was not mutch ,the machien shop was worried about clearance but it dosent hit ,head gasket is ics titan and are .062 thick if i rember right,ok now my rods are stock leanth kb setup and hy heads were shaved 13000 hope this info helps ,already called my machien guy and made a opointment to have this prob fixed but would like to know correct compression again THANKS very mutch  

one more question for you ,i dont want to wast any of your time .I just bought a 1989 gmc 454 and on the block it says high performance pass ,today i got a lunati voodo cam 213/219 .515/.530
' the block is stock and has only 64000 on it ,fresh rebuilt oval port heads,comp magnum roller rockers,lunati hp timing set,lunati pushrods and lunati lifters toped with a edlebrok air gap intake and a holly 750 double pumper,the head gaskets are mr gasket mls and i am going to set my timing at 4deg advance ,what do you think i will get for hp/tourqe from this beast,also i am buying engine softwear wich will help me with the questions i have so any advice on that THANKS  

Did one of my 454's similar. Comp Xtreme Energy 11-231-3. .505@valve, 210-218 dur@.050, 111 LSA, installed at 107 IC. Some of the internals are GM steel crank, GM 7/16 rods, TRW #(2465) dome pistons,balanced, Cloyes billet double roller timing set, Melling stand.-vol oil pump (blueprinted and balance grooves), 781 large oval heads with 3 angle valve job, bowl blended, cleaned the ports, and gasket matched. Did not zero deck block, so I used .020 steel shim gaskets, to keep correct quench, (.038-.040). Static comp ratio with this set-up is around 9.3:1, and it makes tons of torque with that cam! Needs it, as it resides in a 1976 crew-cab dually.Also did another 454 over the winter, and went all out on that one! Check them out on youtube (A169KL). I gave all the specs.for that one (New 454 engine build), in my threads. I will get back to you soon with an approximate comp. ratio needed for your bracket cam.  JW.  

nice vid f-sick  lol mine has all stock inerds by it also has flat top pistons mmmmm nice truck tho ,  

My calculations show that with a flat top piston, with -8cc,s (valve relief's)? .030 overbore = 3.906, - .025 deck height,? 3.25 stroke, estimated + 8cc's head gasket volume @.062? ( would be better with Titan 4.060 bore and .032 thickness for proper quench), 64cc comb. chamber
brings you around 11.94 static comp ratio. I need an intake closing point in deg. ABDC on that cam to tell you what comp. ratio is needed. Glad you liked the video's. What's your 454 going into? Just a guess, but I would say you should see around 350-375 HP and 475-500 FT LBS torque with your 454. A well tuned ignition and exhaust might bring you 400 HP. As far as I am concerned, a broad, flat torque curve is the way to go! And you'll have lots of that. You should consider putting that in your Firebird, and really make some *** happen! Just a thought.  JW.  

jw bb is going in my 89 3/4 2wd suburban trb400,4-11s full race exaust fat tires mmmmm ill have to get my spec card for the cam ,its at the shop but ill get back to you on that  

btdc is -1.5 and abdc is 34.5