billymgb1000

I have a 4.8 with a GM hot cam and a new street deamon 625 cfm runs good but I am just wondering how big of a carb I can run on this or what is the biggest jet I can run in my carb

Horsepwraddict

iTrader: (12)

That carb is probably pretty close to the perfect size for that motor. I wouldn't go bigger than a 650. As far as jetting goes it will all depend on the combination and what the motor wants/likes.

billymgb1000

thank you hp addict that's what I was thinking as far as the 650 goes. but do you think I should buy a jet kit and just play around with them?

Horsepwraddict

iTrader: (12)

I would, the chances that its perfect are slim. Every carb always needs a little tweaking on a new motor/setup.

homemade87

If you don't have one I would consider a wide band air fuel meter . I did without one for a lot of years . I wish I had gotten one a long time ago . I learned you can't tune a carb with out one . It was a big step in being able to tune . Other wise you will be guessing like I was .

imma_stocker

iTrader: (19)

293ci motor turning 7000rpm needs 650cfm on a radical setup.

LLLosingit

iTrader: (4)

In the old days we read the plugs and it's still a great way to tune today. Wide bands are a good tool but will only tell you your AF ratio.... Not necessarily what your engine likes for an AF ratio. In addition to the wideband you should learn how to read plugs, it will give you a better picture of what's happening in your engine.

homemade87

I agree that reading plugs are a good way to tune at the track under wot conditions .

There is a few more ways to tune with a a/f ratio gauge . Some of the things is idle tuning and part throttle tuning . It will also tell about tip in and a few other things . These are things that plug reading will not tell you . If all your interested in is 1/4 mile , plug reading will give you this . But if you are looking for a well manured carb for the street and track a a/f gauge will definitely help .

LLLosingit

iTrader: (4)

Not just at the track and not just under wot conditions you can use plug reading as a tool just as it has been done for decades. Your plugs will tell you more about your tune (fuel and timing) and overall engine condition than a simple AF ratio gauge. Widebands have their place but plug reading will give you more information if you know what you're looking at.