Vortech Carb Enclosure Q

[PhilM]

I have a carb enclosure with a semi modified demon 750. It is on a 500" BBC with a YSI blower. It is running about 7 PSI with 28 degree total advanced locked out.

The problem is that after about 5200 the thing falls flat on its face. I have twin eliminator pumps, a boost refrenced regulator. The fuel pressure is steady about 15 PSI. I have a msd programmable 7/ 10 coil combo.

Any ideas? Is there something in the carb that needs to be modified? I know its not detonating nor is is lean or rich. The timming on the ground electrode looks to be on par.

Thanks.