Turbo for carbureted motor question

[sikryd]

Hi,
I did not see a thread exactly about this, but may have missed it. Does anyone kow of a source of information regarding the use of forced induction on a carbureted application? I have a 468 BBC, solid roller cam, ported heads, good bottom end parts running 10.3:1 compression. I want to know how many pounds of boost I can get away with, without changing my pistons (I'm guessing 5 -6 pounds) Which in my opinion is not worth it at anything less than 9 pounds. I am willing to change my pistons if the payoff in HP warrants it. I would also like to know how I can increase the fuel rate as boost levels increase, do I just use a vacuum FMU? I know there are blow through carbs out there as well as carb box's. I have never had a turbo on my vehicles, so as you can tell I need to be pointed in the right direction. I am pushing about 650 HP right now but would like to see more, maybe in the 800 - 900 HP range. Any help you all can provide is greatly appreciated.
I am not interested in a roots type blower due to the how tall the motor would be with it. I have no desire to cut my hood, and it also rains a lot here in Hawaii.

Aloha

[sikryd]

After doing more digging, I got answers to a lot of my questions.

[PairOf69's]

Check out Turbomustangs.com there is a section specifically for blow thru carbs

[ALLSPEED01]

Don't know if you got all of your carbureted turbo questions answered yet or not. A properly tuned blow through carb actually works quite well with turbo applications. We have just finished several dyno sessions on a 377cuin. sbc with both twin turbos and single 75mm, 80mm,95mm, and 101mm turbos. We were making over 1200 h.p. on 110 octane non intercooled at just over 20 lbs. of boost with a single blow through carb. You will need to lower the compression on your engine if you want to run any decent amount of boost. To answer your fuel pressure question you have to boost reference your regulator by adding a vacuum line to the top side of the regulator. You will need to add 1lb. of fuel pressure for every lb. of boost. If you need anything else, I will be glad to help.
Brian

[Diesel77]

Aeromotive makes regulators for blow thru applications that work off a boost reference, or more simply put you run a little hose from the regulator boost port to a boost source on the hat or in the manifold. You can also use an MSD BTM ignition which pulls timing out per pound of boost, you can adjust the timing taken out per pound of boost from 1 to 3 degrees. Between the hat, 750 or 850 carb, and MSD BTM its less than $1500 and they work fine especially for cruising around and even work well in lots of 6, 7 and 8 second race cars. Now if you go with like a FAST EFI, full injection system, injectors, throttle body etc .... wooohooo big money, maybe $6k on up to over $10k depending on the injector size etc .... definately a much nicer and more tuneable set up but definately expensive and more times than not you will need help getting your car running right if you arent familiar with fuel curves and or computers.

[ccracin]

Just to let you know, if you are making a true 650 now you will meet your goal with 6psi. 14.7psi + 6psi=20.7psi/14.7psi=1.41 power factor. 1.41x650= 915hp x .95eff.= 869hp. Not bad!