Well i am putting a 1994 LT1 in my 3rd gen. For ease and what i feel is more realibility i am getting the GMPP to carb an LT1. So here is my question.. I want to use a deamon carb but don't really know what carb to install, what CFM and jetting to use.

any help is greatly appriciated (Sp?) and links to flow charts and personal experances help too.

TIA, Aaron

 

I would use a 650 to 750 cfm depending on how hot the engine is gonna be.

 

well i am using a CSI electric water pump, HD radiator and 180* t-stat. mods consist of 1.6 rockers and LT4 hotcam. I am worried that a 650 may choke the motor but i don't want a carb that is too big and negate benfits of the bigger carb.

 

A 650 CFM carb will feed a 350 engine to 6400 RPMs, assuming 100% VE.

Most people go to a 750 w/o penalty.

 

With that combo I would go with a 750 cfm. That won't be too big for you.

 

I'd go 750, A buddy of mine went w/ an 870 Holley Street Avenger
on a 350 and after debating on too much carb for the motor,
It works perfect. I still think it may be too much carb though.

A 700 just might be right, still I'd go 750.DUECE

 

Street Avengers are vacuum secondary. The larger primaries will affect throttle response somewhat, but the VS will only open as far as demand requires. So, it probably isn't using all the carb, and most likely would be just as fast with a 750 or even a 650, and would probably have better driving manners with the smaller carb. May even get better 60' times with a smaller carb (depending upon the total package set-up).

 

ok, split in the middle.. what is everyone's .02 on this carb?

Demon 725VE

 

If you are going to use the vehicle for towing, use a vacuum secondary type.

If you are building a performance vehicle, do it right and go double pumper.

 

57, can you do me a huge favor? can you hop on summit and show me what carb you are thinking of? :hail:

 

Vacuum secondaries will work fine in a performance application. You just have to know how to tune them correctly.

 

http://store.summitracing.com/partde...ew=32&applid=% . Add the choke kit for the street.

Especially for performance towing.

Look, I've heard all the DP/VS arguements, ignored the advice of Jester & Co. (and racing buddies) before buying, let experience be my teacher, finally "saw the light" last summer. Forget peak torque/HP. Size the carb to avoid off-idle WOT bog (Holley/Urich chart), and DP will out-run VS every time. And do it with more consistency.

 

A 650cfm carb is more than enough for your motor. You only need to flow 617 cfm for that size motor, so even a 650 is a bit too much. As far as jetting in the car, it depends on your location, elevation, weather conditions and tons of other factors. Start with what comes in the carb, and dyno tune or track tune it, but use some method that can track the improvements, not just how it feels.

 

I have used both kinds of carbs. I was just giving my experience.