Made it to the races, boat looks great, runs the quarter at a (choke) 49mph, runs good but won't spin faster than 4200. Wondering if its a pump problem or the stock mechanical fuel pump, waiting on fittings gonna add a Holley electric pump, just hate to keep throwing money at it if its a lost cause. Nobody spoke real highly of the olds/jacuzzi combo at the races. If I had 20,000 burning a hole in my pocket it wouldn't be quite such a problem....I R 1 broke bastard...missin my oilfield check, sidelined with a shoulder injury. Any help y'all can offer would be awesome. Doesn't have to run a 100, be nice to outrun the neighbors kids canoe...lol thanks y'all, Keith

Need more info/specs on the boat.
Assuming its a 455 Olds and a WJ, "B" impeller combo, you are way down on horsepower.
4200 rpm is ~225 hp,  according to the WJ Impeller chart. The stock olds in the '70s were rated at 320-325 hp, and should turn a "B" impeller @ ~47-4800 rpm

Suck,
Squeeze,
Bang and
Blow...where's your motor at?

What carb and what's it jetted at, and how much fuel pressure at WOT? Secondary's opening?
How's compression and leak down?
Where's your ignition timing at?
What exhaust system?
What has been done to the pump?
Once the motor will turn the pump to its rated hp, then on to the bottom hardware.

If its not a 455 and WJ-B, this won't help much.
Hope this helps.
Dan'l

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