Extreme G Chip for MAF Translator Gen II Parameter 8 Knocklite

Leightoning

New Member
Im hoping some of the experts can help Me figure out my car.

I have a wideband afr and boost gauge on my car. If I mash the gas pedal (not even having to go wide open) it falls on its face for a split second and reads very very lean. It then will pick up and build boost just fine (around 9-10 psi) when it is under higher boost, it reads further rich than the gauge can even go. (It still pulls very good though)
My first assumption is the PEVR may be bad. Or I have vacuum lines in the wrong spot?
May even need to adjust the secondaries on the carb.
Let me know if any of you have advice for me. Can provide more info if needed.
Thanks!
 

ShawnR

Fixer of crap..
My first thought would be that the secondaries are opening up too quickly (or slowly) and it sits there for a sec starving for fuel. The big flaps on the top have a spring holding them closed and I think the air flow just forces them open at the rpm's go up. There is a little set screw on the passenger side of the carb that you can adjust the spring tension that holds them shut. Make sure they are lubed well too and aren't sticking.

Probably not the reason for running rich, but would account for the bog when you mash it. Make small adjustments and check for vacuum leaks.
 

b4black

Well-Known Member
Is the engine fully warm and do you have all the emissions stuff in place (probably not).

When cold, I believe the fuel puddles under the carb for a second. Or maybe it doesn't, but I always have that stumble when the engine is cold. I don't have the stock air cleaner box, which uses the heat riser pipe to the exhaust manifold. I also don't have the EFE in place. On you car, this is the butterfly valve in the driver's side exhaust manifold. Both these heat up the incoming air to better atomize the fuel after the carb.

These car are likely calibrated very rich from the factory to supress knock using 87 octane fuel (no unleaded 93 at the time). Get slome difference secondary rods for the Q-jet and play with them to get the AFR leaner. But make sure you not knocking first.
 

Leightoning

New Member
Thanks for the replies!
I tried tightening the spring for the secondaries and it seemed to make the bog even worse haha. So I went back to as loose as they would go and it was about the same as before.
This car is a project that my dad and I fixed up about five years ago. It sat for 20 years and most of the emissions stuff was in bad shape, so most of it is gone now. I have put a 3” Custom intake with a k&n filter on it. Yes the car is fully warmed up when I mash the throttle. That totally makes sense about the mixture being rich from the factory.

I’m young and don’t really care for carbs that much. I’m not as worried about it being rich at wot now as I am about the initial lean. I would just put a TBI setup on it, but whether that old engine is worth the money I’m not sure.
 
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