Dyno Day! Question for engine builders - A/F correction factor for dry dyno headers?
#41
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My friend sometimes wishes he had picked up a Rage instead of a Heat. What were you running with the 502, mid-70's? He is getting about 63 with a 496 HO in his 28 Heat. He has talked about making some upgrades to it, but I told him to leave it alone and enjoy a turn-key boat. Seeing me walk away from him is going to make that tough on him. 
The only thing I don't like about the Heat is that (at least on his boat) there is no way to close the cabin off from the cockpit and bow, so if there is a heavy rainstorm you will probably get wet in there. Also, when you get running, it acts like a wind tunnel - you better make sure all the towels, hats and can huggies are secure!

The only thing I don't like about the Heat is that (at least on his boat) there is no way to close the cabin off from the cockpit and bow, so if there is a heavy rainstorm you will probably get wet in there. Also, when you get running, it acts like a wind tunnel - you better make sure all the towels, hats and can huggies are secure!
#42
#43
Nice run stand, I dig it! I'd probably start with the 23p mirage plus and see what you get. I'd probably shoot for 5500rpm at wot. If you rev too high, then try the 25p mirage plus. I wouldn't bother with the bravo 4 blade. Too much diameter for a deep drive setup. I'd bet ya a six pack a bravo 4 blade will kill the speed on your boat. If you want to try a 4 blade, the Revolution 4 blade works well, in applications where a mirage plus works well. The Rev is 14 5/8 diameter, but high rake and provides a lot of lift.
#44
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From: AZ
My Rage did a best GPS speed of 78.5(had a few things done to it) with a couple bigger guys in it (myself and previous owner). I'm estimating my new engine should make around 625hp or more, so that should get me knocking on 90. The Rage is about a good 10 MPH faster than the heat. I looked at a few heats, but wanted a smaller more trailer able boat that had more speed potential with less horsepower.
Regarding the open bow, yes it can be a wind tunnel at times when left open. The rain thing doesn't apply, I live in a Phoenix and it rains here like twice a year (was about 108 here today). That being said, I have a custom support for my front cover that is usually in place and it eliminates the issue of turbulence in the mid cabin
. I think Nordic hit a home run with this design. People constantly comment on the boat. And the MCOB just fits the boating lifestyle here so much more so than a closed bow. When it's Africa hot here, all a cuddy is good for is a makeshift sweat lodge to lose those last few winter lbs...
I bet you are excited to go out and surprise a few folks in yours! Things gonna rip. My cam is quite a bit larger than yours, Lift: int 654/exh645 duration 237/245 LSA 112 (dry exhaust), but I really like how you utilized the smaller oval port heads. My dart pro 1's are 275's, so not much larger than your AFR's. Oh and I'm almost at 10:1 compression. Can't wait to dyno it. Anyways enough about my project, back to your thread. Post up more pics!
Regarding the open bow, yes it can be a wind tunnel at times when left open. The rain thing doesn't apply, I live in a Phoenix and it rains here like twice a year (was about 108 here today). That being said, I have a custom support for my front cover that is usually in place and it eliminates the issue of turbulence in the mid cabin
. I think Nordic hit a home run with this design. People constantly comment on the boat. And the MCOB just fits the boating lifestyle here so much more so than a closed bow. When it's Africa hot here, all a cuddy is good for is a makeshift sweat lodge to lose those last few winter lbs... I bet you are excited to go out and surprise a few folks in yours! Things gonna rip. My cam is quite a bit larger than yours, Lift: int 654/exh645 duration 237/245 LSA 112 (dry exhaust), but I really like how you utilized the smaller oval port heads. My dart pro 1's are 275's, so not much larger than your AFR's. Oh and I'm almost at 10:1 compression. Can't wait to dyno it. Anyways enough about my project, back to your thread. Post up more pics!
Last edited by Borgie; 05-30-2014 at 11:22 PM.
#45
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Borg, you are right about the MCOB fitting the west coast boating style. My friend had a hard time finding one east of the Mississippi. I think he ended up finding his boat out in Utah. I agree about the styling of the Nordic's too - I have always liked them. Regarding the MCOB, I have always wondered why one of the boat makers hasn't made a boat with a MCOB design with a fiberglass cap to convert it back to a closed bow if needed. Add a few fill cushions in the bow and you have a forward berth = best of both worlds.
108* in May? I don't know how you stand it, although it has to be better than the sub-zero crap. I hope you guys don't run out of water out there. That drought is some serious shizit. Thanks for the good words, and good luck with your build. Looks like you have all the right parts going into it.
108* in May? I don't know how you stand it, although it has to be better than the sub-zero crap. I hope you guys don't run out of water out there. That drought is some serious shizit. Thanks for the good words, and good luck with your build. Looks like you have all the right parts going into it.
#46
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From: AZ
Borg, you are right about the MCOB fitting the west coast boating style. My friend had a hard time finding one east of the Mississippi. I think he ended up finding his boat out in Utah. I agree about the styling of the Nordic's too - I have always liked them. Regarding the MCOB, I have always wondered why one of the boat makers hasn't made a boat with a MCOB design with a fiberglass cap to convert it back to a closed bow if needed. Add a few fill cushions in the bow and you have a forward berth = best of both worlds.
108* in May? I don't know how you stand it, although it has to be better than the sub-zero crap. I hope you guys don't run out of water out there. That drought is some serious shizit. Thanks for the good words, and good luck with your build. Looks like you have all the right parts going into it.
108* in May? I don't know how you stand it, although it has to be better than the sub-zero crap. I hope you guys don't run out of water out there. That drought is some serious shizit. Thanks for the good words, and good luck with your build. Looks like you have all the right parts going into it.
Last edited by Borgie; 05-31-2014 at 11:14 AM.




