Ricisan

I'm trying to get the most out of my SB. I've got a 750 VS on a 425 hp combo. 10.25 cr 218-224 @.50, air gap. The stock jetting is WAY TOO RICH. Can anyone give me a good starting point before I go to the dyno? Thanks for the responses.

MIKER

Take a look at this thread. While dyno testing they used two different Demon carbs and showed the jet numbers.
http://forums.corvetteforum.com/zerothread?id=229013

Speed Demon Carb
(625 cfm Road Demon) w/ jets at 70/76
750 cfm 81/88 jetting

gdh

I have heard nothing but positives about this carb. Did you guys get the same 20 - 25 hp increase over similar Holley or Qjet that others have recorded?

gkull

The stock jsetting is 76/83 . Where is your problem? I bought the no choke DP model. It was so rich at idle i had to do the normal Holley trick and drill each pri throttle blade .125 hole in each. Then drill out the squirters from stock .035 to .044

Your right at sea level. so the real problem is Fat on the cruise. So try 74 ish and 82. I use max jets so they are near to holley but better.

Make sure your Squirter arm is Zero so it hits fast.

I did not look up your advance or tranny type. your need about 12-14 inital and then with the holes drilled in the throttle blades you will have a bigger range of adjustment with the four corner idle screws. @ 1 1/2 out each after drilling. set your idle to max vacuum with a gauge. always set the secondary blades to increase the correct idle higher than the pri's

That way when you go WOT it's a smoother transition......... :seeya

Just ask LARS the carb wizard