I've got a GM 2BBL TBI on my performer manifold. I'm running Howell EFI on mine. www.howell-efi.com I had to grind the inside a bit with a die grinder to smooth the transition between the manifold and adapter plate. Howell will adapt their wiring harness to use a Holley 4 BBL TBI that fits right on the performer if you ask.
I love the Howell system. Aside from a bad O2 sensor, it's been flawless for nearly 10 years now.
Bob
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