New Engine Finally Ready!
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Location: Minneapolis,MN
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New Engine Finally Ready!
It took longer than I wanted, but I just took the new engine off the dyno yesterday. Looking forward to getting it back in hopefully in time for the 4th of July.
388 C.I. SBC Converted to EFI 425 HP @ 5400 RPM and 441 Ft. Lbs. @ 4800 RPM. Can't wait!
388 C.I. SBC Converted to EFI 425 HP @ 5400 RPM and 441 Ft. Lbs. @ 4800 RPM. Can't wait!
#4
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Very Nice!! At what RPM are you seeing 400 Ft Lbs ? I'm interested in your build/engineering and curious about how the TQ is at low RPM.
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I'll post the two dyno sheets. One of the stock tired 260 Merc and one of the new engine. At 2300 where the pulls started, it's making 386 Ft. Lbs, and has over 400 Ft. lbs from 3200 RPM to 5500 RPM.
The dyno sheet shown for the new engine is without the flame arrestor and running the air flow meter instead so it was running a little bit lean. For the real world test I took 3 stock "short" arrestors and took them apart, stacked them and made one taller unit. This generally took 15-18 HP from the engine through out the RPM range. All tests were done with the marine exhaust manifolds and water through them obviously.
The dyno sheet shown for the new engine is without the flame arrestor and running the air flow meter instead so it was running a little bit lean. For the real world test I took 3 stock "short" arrestors and took them apart, stacked them and made one taller unit. This generally took 15-18 HP from the engine through out the RPM range. All tests were done with the marine exhaust manifolds and water through them obviously.
#7
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Jim,
Check your PM...this site won't handle xl or pdf files.
With your engine running that strong of a TQ curve...you've got to be thinking 1.35 gears and 23"~25" prop...and some REAL GOOD TRIM TABS.
That 242 will only need wings to fly.
Check your PM...this site won't handle xl or pdf files.
With your engine running that strong of a TQ curve...you've got to be thinking 1.35 gears and 23"~25" prop...and some REAL GOOD TRIM TABS.
That 242 will only need wings to fly.
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I'm finding myself always making too much power lol I'm going to get it running and get the installation/conversion worked out and then I'll see what I need for props etc.... at this point the wife just wants to go on the boat
#10
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This guy has some decent ideas.