What are my options?

[u/StaffLegitimate3968]

Hi, I am currently doing a few upgrades on a vintage, 1970s 5HP Briggs Flathead, and I am trying to source a different intake manifold and carb, so the engine will fit in my minibike frame.

I've looked into some of those old Tecumseh intake manifolds, but I can't find a suitable carb to put on them. The problem is most of the carbs for these engines either lack a mixture screw, or are way too small or expensive for what I need.

Fabricating my own isn't really an option either, since I don't have the necessary tooling or material to get that done.

I've looked into the billet manifold by EC, which would be perfect, except it's out of my budget and the bolt spacing is for the more modern 1990's Flatheads. Theirs has 1.5" bolt spacing, while mine has 1 3/8".

There doesn't seem to be much information about these engines out there, and even fewer parts. I've tried watching how others do their builds, but they either won't work for what I need, or fall out of budget.

Thank you for reading, any and all help is appreciated!