SBC 406 carb and intake change advice

[Prostreetbike]

Going from a set of heads that flowed about 238 cfm to a new set of aluminum ported heads that should go 290+ at .600 when they are done. Old combo was a 406 with a old comp 292 hydraulic, 11:1 comp, RPM airgap with 750 Holley DP carb. Car is 3400 lb camaro, 3:73 gear, TH350, 3000 stall.
( Car sounded nasty and was fun to drive.)
I am also going to recam while I am freshing up the motor. Thinking about solid lifter flat tappet, or hydraulic roller. Not sure about the difference in gain between the two with this mild street engine ?
I was thinking about shooting the info to Cam King and getting his advice. The car is a weekend toy, mostly street car.
I am also thinking that the old carb and intake are going to be a choke. What do you guys think about a Holley Strip Dominator 300-25 and a Holley 830 Annular booster carb #80511-1 ?

[lefty o]

i think the strip dominator is an excellent choice.

[Prostreetbike]

From what I can find the Performer RPM airgap flows about 210 CFM. If you port match it and do a little plenum work and got it to 230 or so I wonder just how much HP that could support on a 406 ? And how it would do with a bigger carb ?
It would take a lot of port and plenum work to get it to flow the 300 CFM that the Holley 300-25 will flow for just 235.00 brand new. I might can even find a nice used one.
Do you think the 830 annular would be OK on a single plane intake, or should I just keep using the old 750 DP ?

[cab0154]

I would do a 300-110 with a little plenum work and a port match and use an AED 950 HO. you will be amazed at the difference.

[Prostreetbike]

I like the 300-110, but I think it is another 1" taller, which is tough on a camaro hoodline, and another $100.00, so the -25 would be easier on the wallet and hood clearance.
I see the AED 950HO is advertised as basically 750 with 850 plate, 820 CFM carb. Do you think I should go for the Annular boosters on the single plane, since it is largely a street toy ? Or will it be unnoticable with the 3000-3500 stall anyway ? Just wondering if it would have better low speed part throttle with the annular boosters ? Or no difference with 406 cubes ?

[cv67]

not a fan of comp but their 282s isnt bad lots to choose from
More specifis on heads so they can help

found q 300-110 and 300-25 by bugging a guy on ebay "holleyperformance"...had 1 of ea one new one returned (usual bolt holes dont line up stuff)cheap too!
they got all kinds of stuff laying around but youll have to contact them and ask

[Bogus1]

If you are using the stock hood, air cleaner and intake manifold height become a major issue when making a determination on what to use. I have used the Vic jr, RPM and AFR TXS with the stock 70-72 Z28 air cleaner assembly without any clearance issues. I own several 2nd gen Camaros and the other issue is traction if your car makes any power at all.

As for cam choice on a street driven 406 any will work. My old 406 with ported Sportsman II heads and an Isky solid flat tappet 249/259 @ 050 , Vic Jr and 850 carb ran 11.10 at 122 mph. That was with a mild stall and 4.11 rear gears. Ok car to drive around town but not to fun to drive on the highway. At current time my 70 has a 406 with the Comp 4 pattern (recommended by big joe) hydraulic roller and the 72 has a Crower solid roller 406 AFR 210 deal. Both cars have Calvert track bars/split mono leafs with Afco shocks. Any 406 with a decent head, carb/intake is going to make over 500 ft lbs of torque so traction will be an issue in a 2nd gen Camaro.

If your car is truly going to be street driven I would stick with a hydraulic roller and try to make peak power around 5800 - 6200 RPM. Your 3.73 gears are a little steep if your running a 26 inch tire. A 3.42/3.31 gear and 26 inch tall tire with the RPM intake and hydraulic roller would be more street friendly.

Once your heads are complete, get some flow numbers and contact any of the cam guys here, Camking, Chris Straub, Bigjoe1. They will give you there advice on Cam/intake/carb size based on your goals.

Good luck with the build.

LJ

[jmarkaudio]

Stay away from the 830, throttle blades are smaller. The 80514 1000 Holley or Q1050-AN Quick Fuel would be a better choice. Or better a custom based on the QF or BLP billet body.