her is my setup,
1989 Chevrolet silverado 1500
Ladder bars w/ fab 9'' w/ 4.56 gears
31x10.5W tire on a 15x13 1/2 wheel
505ci BBC
14.1 JE Pistons
Dart Pro 1 325 Heads w/ Shaffirof Porting(not CNC)
Custom Ground cam around 750 Lift
Dart intake w/ 1050 HP dominator
TH 400 w/ Hipster Brake
Truck weighs around 3800 w/ Driver
Best run to date is a 6.46 w/ a 1.39 60ft

What kind of gain will I see If I change from a gas to an alcohol carb and what are the advantages

alcohol can be more consistant(can be) if it's dialed in right. Are you taliking an alky carb or mechanical injection? Usually alcohol is worth a couple of tenths.
Lately there have been many of alky guy's going back to gas...
I think a good gas carb with the right tune is the way to go.

Call George Rupert in Cookeville,TN.sorry don't have his num.on hand.He builds some of the best Alcohol Carbs in the nation.Tell him what you have and what you want.He WILL help you.

I had a Vega with 355 SBC, 11:1, bowtie heads, 800 cfm carb, pg 5200 stall. Best run with 110 race fuel was 10.37. Switched fuel system over to alcohol with 950 APD carb and ran 10.01. The only thing I switched was the carb and regulator. APD is very popular at Grand Bend Motorplex. Switching to alcohol was a bit of a learning process for me. Pick the brains of the guys running it at your track. You'll learn all about lean out valves and changing your oil more often. PM me if I can help out.

On several BBC's I've seen dynoed, including mine, a "good" alcohol Dominator was worth about 30Hp and about the same in TQ. It "usually" lowers the TQ and HP peaks by 200-400 RPM, but not always.
What I have seen at the track with my Camaro is, during the summer when the air is bad and temps are hot, the alky is much quicker. When the air is cooler the difference is not as much.

I have gone 5.97@115 in 45* 1000'DA air with C12.
5.95@115.8 in 80* 3700' air on alky. I didn't get a chance to run in really good fall air, but shoud get more chances early next year.

In the heat(95*+) I went from 6.20's footbraking on gas to 6.0x's footbraking on alky. Consistancy is much better with my combo on alky.

I agree with Jay. The air has to change ALOT before my car changes. Plus, in Texas the racing season is HOT.

By the time I get back to the trailer after a pass, my car is down to 160 if I don't pull the leanout. I leave the fan and pump on for a few minutes while I refuel and the car is at 145 and ready to go again.

My 355 combo is deadly consistent on alcohol. 9.35 in the spring and fall, 9.45 in the summer. What it runs out of the trailer is pretty much what it runs all day.

Randy