New motor for the Tantrum
#11
#12
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Joined: Nov 2003
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From: Lake Travis ,Texas
Its finally done. Still needs paint. We dynoed it yesterday and made 693hp at 5500 rpm through 5700 rpm, 733 tq at 4500 rpm.
Its a 555ci gen. 4, bowtie tall deck roller motor. Merlin 320 iron heads w/ little work, 1050 dominator, 9.6-1 comp. ratio, 26* timing on 93 pump gas.
Its a 555ci gen. 4, bowtie tall deck roller motor. Merlin 320 iron heads w/ little work, 1050 dominator, 9.6-1 comp. ratio, 26* timing on 93 pump gas.
#13
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Joined: Jul 2009
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From: Taunton Ma
He did, but the 572 made a lot of torque and peak hp wasn't real high. Anything over 5300 rpm could guarantee the drive was broken. I believe he had a 32p bravo 1 labbed and was on the limiter with ease. It should definitely be faster than what I was saying just busting chops. Glad to see some good power back in that hull!
#14
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From: Taunton Ma
The x dimension in his boat is a lot higher than most of the others. If you have a standard build boat I believe you're drive would end up to deep and slow the boat down. Iirc his even had a 1.5" spacer in the drive even though the box allows for higher drive height.
#15
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From: marbury, md
#17
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From: marbury, md
I have the KE cast aluminum long headers, so I dont think I am going to loose much there and with all that torque....accesories. I know the number will be different once installed and hooked up and spinning a prop, but at least I wont be playing the guessing game when trying to prop it to the right rpm. That was my main reason for dyno testing.
#18
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From: marbury, md
Timing. we started out at 22* and autolite 23 plug and only made 650. then went to a colder NGK plug and 26* then made the 693. Then 29* didn't show any improvement as stated before.
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