[MidnightAuto]

Well I am opening the patient up (see other thread about adding a pusher pump to help with start up) and it dawned on me that I might look at things a bit more holistically.

I dont hit WOT often, but the couple times I have, I get some backfiring out of the carbs at the top end. It happens in any gear, probably around 5000 RPM. My suspicion is that the small rochester bowls are getting drained and i have a fuel starvation problem. I like my tripower, but I know its probably not the best for 1/4 performance after a certain threshold.

So I am wondering if enlarging the fuel block and lines around the carbs to 3/8 from 5/16 would help. It looks like the center carb has an adaptor at the inlet that could be replaced - its currently fitting for the 5/16 inverted flare. the end carbs is a different story and appears no easy ability to open up those inlets. that adapter does not seem like something readily available though. worst case, I run 3/8 fuel block and lines all to inlets that have a 3/8 to 5/16 reducer. Feels like that may defeat the purpose some, but wanted feedback.

thoughts?

reminder on my setup - stroked 421 to 461. KRE 290 CFM. 60919. Headers/3" exhaust. 1/2 inch fuel sending unit and fuel line to regulator. robbmc mech pump. 3/8 line regulator to fuel block. 5/16 lines after that. tripower venturis have been opened up and all the accompanying tweaks from Dick B. 1" spacers under each carb. MSD ign. TKX 5 speed. car is no slouch, but feel something is being left on the table at the top end.

It would be easy to throw a 850 holley and an electric pump and call it a day, but id like to keep the tripower cool factor.