jet kit

[willyj]

What is a safe size jet to run? 409 sbc steel heads 7500 max. 110 vp gas. the 750 Quick Fuel we have comes standard with 74's.Tech at QF sugg. 70-80. I was thinking 82-ish. 12.5:1 500 hp or so.I would like to buy a kit but dont know the range i would need. Anyone use the comp cams maxjets?

[fast_crew]

That is hard to say with out checking the plugs properly or tuning on the dyno, 82's would be too rich. There is bit more to the fuel curve then just the jets aswell.

[willyj]

I just want to run practice laps for the seat time. Im not out to get max hp right out the gate.Looking for a safe size that will run fine but be in no danger of being too lean.If Qf put 74's in it and run it on a sbc test eng. I think 74 would be close,but im not an engine builder.I guess the ? was what is the average jet size for sbc 4bll application.

[runyou-2]

I would run a 74 in front and an 80 in the back.But,i would have a by-pass regulator AFTER the carb with a 70 jet and return to the tank.3-4 pounds at idle and 9-1/2 - 10 at full throttle.Then check your plugs but i'll bet you will be about right.