I rebuilt the 7042240 carb when I put in the TA 284-88H cam (223/230 at .050), expanding the idle down channel and idle tubes to .062" so the engine would idle without surging. Everything worked and the car drove well, but I recently ordered a set of TA Stage 1 SE heads with a level 1 port job. Will the flow increase (from stock iron - NOT Stage 1 - heads) require the carb to have bigger than stock jets? If so, what jet/rod combination is recommended? While we're at it, what secondary rods should I use? Currently I'm using CV. Thanks, Matt
A every car is different. The best way to tell is get a wideband O2 sensor in the exhaust and tune away. Of course you have to have a lot of parts and time to do this, but it will be well worth the effort
Impossible to answer question. Improving engine efficiency is just as likely to require leaner settings than richer. Improved cylinder filling improves effective compression, VE goes up, etc, might just as easily do more with less fuel. In any and all cases, install the carb as is and do some testing. Easing into the throttle right off idle, light throttle cruising, heavy part throttle, and full throttle. An A/F meter is a complete waste of time/funds, IMHO. If you tune the engine for best idle quality, best part throttle response, best fuel economy, and ET/MPH, the A/F will be where it's supposed to anyhow. In addition, the requirements for every engine are different. About all a meter does is tell you when you are WAY off the mark, and point you in the right direction. Don't forget distributor tuning in conjunction with carb tuning. Adding timing at cruise via the vacuum unit will allow for leaner mixtures, and better cylinder filling at full throttle may require less total timing with the addtional effective compression, etc. The very best place to tune for full throttle A/F is at the track. "Seat of the pants" tuning can be very miss-leading. Every single time I've bolted on a part or parts that felt quicker on the street, my car slowed down at the track!.....Cliff
