I tried different situations.
I noticed that when I floor it and I am uphill, the a/f ratio is good but when I am on a flat street or slightly downhill, I get a lean signal.
Another thing is if I floor it, let it go to 5000rpm and just release the throttle a tiny little bit, the a/f ratio is back to good and the car is way faster. It is like I am accelerating more.
Any ideas?
Can it be that my trottle bades open way too much at WOT?
A vaccum problem?

Thanks for your help,

Jacques.

 

WOT = Wide Open Throttle

I don't think there's any such thing as throttles opening too wide. Even if they could move too far mechanically, they would simply start to close again.

Too lean at WOT usually means you need a heavier spring in the diaphragm that opens the secondaries. Buy a spring kit from Holley, try the brown one and the black one, see if one of them is about right.

 

I think I would try larger secondary jets.

 

As soon as I can I will try to change the spring in the diaphragm for a heavier one.
I know I need a stiffer one cause when downshifting, the car bogs meaning (I think) that my secondaries are opening too soon.

I don't want to sound annoying but can somebody tell me what is involved in changing the spring.

Another quick question, does anybody think that having that single plane manifold (I want to change it) on a small engine can make it run lean at WOT?

Thank you for your help,
Jacques.

 

I didn't notice that... a single plane intake on an otherwise very mild small-cube motor will make it a total dog off the line. I couldn't say for sure what effect it would have on A/F ratio at WOT. Your combo is so badly mismatched that it's pointless to try to tune it with things like an A/F ratio meter; you need to put some stuff together that will work together all toward the same goal, rather than having a motor with low-flow swirl-port heads (designed to promote low-RPM torque at the expense of high-RPM flow) and an intake that is designed to produce power from 5000-8000 RPM at the expense of low-RPM torque. Yo uget the disadvantages of both and the strength of neither.

Put a Performer or at most a Performer RPM, or the equivalent Holley product, or a ZZ4 intake on it; then start trying to tune it.