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She’s done but needs tuning!


Well-known member
Finished the rebuild but gotta tune the holly 500.


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If that motor has 470 cut down pistons to bump compression, then it’s like mine. Abners shop was real nice and gave me the scoop on what to use. So far it’s night and day different and I wish I tuned it years ago.
Power Valve - 10.5
Squirter - 35
I can’t remember what accelerator pump cam I have but I think I have it set to hit quickly. If you have a vertical spacer underneath the carb you may want to remove it. Keep the carb as low as possible to the manifold. Good luck!
Thanks! It’s a 220 gpu with dual mags no other noted enhancements from the former owner, has the spacer since the carb won’t sit flush (Holley 4412). Gotta clean some paint around the starter mount and/or replace start button, initially it would respond to the button being pushed, messed around tested the wires etc, roughed one bolt on starter and got it to respond, now after a couple weeks back to nada on starter, so I gotta go and source the issue. Still have 12 days for paint to cure on hull. Also, just finished making some rain covers out of weather max 80 material for the seats.C4CEAE16-0C25-4D98-9BE9-C1E0ED34CD1A.jpeg


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kwanjangnihm said:
bama are you running a battery ground cable close to the starter on the engine?

No the case ground is lower L corner above the oil sump but that was my next thought, run a dedicated ground to rear bolt on starter. I also have yet to see my oil temp work which tells me the gauge needs a dedicated ground, all new. My fuel gauge was working had some hiccups showing full only and not going through test then back to normal and I’ve been reading these gauges need their own ground to avoid electrical gremlins in the line. Lol. Not sure what make model starter, I’ll post a pic when I get off shift, pulling a 48 now.🤪
Looks good Bamasoflorunner.

I've got a future gpu project in the makes and will be reading up on your's & other gpu threads...thanks


I am on-board with Kwan on the ground to starter cable, you will notice the difference. That said, if she won't turn over now, the ground cable is not all that needs sorting. I have new everything in the start circuit, Norman Clay starter, Optima Blue top and #1 AWG ground to starter. I can get back to the ramp on starter alone if needed.

Call me a P***Y, but I will walk out vs. hand propping my 6 cylinder stuff, and I don't like walking :slap:

It sounds like you have a crappy ground connection from the battery to the console. Run ground straps between everything. Other than a #1 or 2 AWG ground to the starter, run a minimum #10 AWG from the battery to:

- Starter mount, #2 AWG minimum
- Engine Stand (I run a #1 AWG to here and all grounds out from here)
- Engine Oil Pan (I run another #2 AWG here)
- Cage
- Hull
- Other rigging not welded to cage
- Ground to console ground strip

Most electrical problems involve grounding. 12 V negative ground systems result in corrosion at the ground, the system anode. If the ground is bad, things like starters and Ignition twist up the amperage to make up the difference, creating more heat.

You just repainted the whole thing, finish it off right for 5 years minimum of trouble free riding :cheers:

Don't cheap out now :violent1:
😂 yeah that’s not happening, I have all the stuff just gotta do it, prep to go camping, had to wax the land yacht, shes been neglected since February. So when paint finishes curing it’ll get done.


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Still shaking her out. Have a starting issue. Once running she hums. I thin the gaskets are backwards or the accelerator pump has a blockage. Last run 15 miles give or take total. Initially float bowl was low, when warmed up would re-start, have to use ether when cold. Now float is where it needs to be, and it only starts with fluid. The accelerator pump is hard so I know the gasket is backwards or there’s a blockage. When I get back from Ga bow season gotta take it apart. Points are good and timing should be on.


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