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Just curious to see what what you all think my speed is. I havent had a speedo or GPS in yet to find out...
My boat is a 16ft 1979 GMC CobraJet, Berk "F" pump with an "A" impeller. Pump was just rebuilt using an Ultimate wear ring from HTP. Engine is a fairly stout 468 BBC...
I have touched 5300 RPMs briefly, but for discussion sake, let's say @ 5000 RPM.
Years ago, with the stock engine, worn pump (not sure how worn, but used condition) and 3 people on board, a handheld GPS said 70 MPH as top speed (not sure what RPM)
Any guesses???:idea:
65
Any serious guesses?
Here's a dead serious "guess" -
62 mph.
62mph @ 5000 rpm's would be moving pretty well.
Get a GPS, then share the info with us.
Sure will, but it sure feels like it's much faster than it was before...
Finally got it out on the water with a GPS. One passenger and full tank of gas, I was doing 64 mph at 4800 RPM, so the guesses were pretty close!! However, I cant seem to get past 4800 now. One change I made was that I put on a scoop that might be a bit more restrictive than my 4" tall flame arrestor. Anybody have any experience with this? I'd hate to lose the scoop because it looks killer, but I dont like the idea of giving up any performance. I going to try switching back and see what happens. Trimming didnt seem to have much affect on top speed...
:idea:
You have to take into consideration that your old worn out pump is not efficient, allowing the motor to rev higher. 4800 isn't bad, but probably not far from peak with a few tweaks.
This is all with a new engine a freshly overhauled pump & UWR. I have hit 5300 RPM, and although I didnt have a GPS with me, it definately felt faster than it ever has been. I put the scoop on the engine and I seem to have lost 500 RPM and it feels a tad bit slower (I just recently got the GPS). With the stock engine and worn pump I had a GPS reading of 70 (I dont recall the RPM, and as the pump is now rebuilt it wouldnt help with comparison anyhow)
I seem to be having some issues with my throttle cable, and it was only opening about 3/4 of the way...
Any guesses at what my speed might be ay 5300 RPM?? Hopefully I will find out this weekend...
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