SoCal Jet Boats
Tech Talk => Engine Mechanical / Electrical => Topic started by: N2GLOCK on June 13, 2011, 02:45:45 PM
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I've been looking at used over the transom headers for my BBC and I'm a little confused. The two brands I'm interested in are Rewarder and Bassett and I've seen the word term "twisty style" used on several occasions. Some of the headers I've seen are listed as twisty style and others are not. Honestly, they all look the same. Is there a difference between twisty and non-twisty or are they all the same?
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The difference as far as I know is simply in the way the headers are built. Twisty style headers are more narrow, or closer to the engine block than the regular headers.
Here's a shot of standard headers
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fwww.rewarderheaders.com%2Fimages%2Frewarder%2520v%2520drive%2520boat%2520header.JPG&hash=63d0de3fe2b8fd1743b32334e219564a31a1d745)
Here's a shot of twisty headers
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fwww.rewarderheaders.com%2Fimages%2FRewarder%2520Headers%2520454%2520Chevy%2520Twist%2520Boat%2520Header.JPG&hash=ed1a63922493da166ea1a544933464371befc306)
Notice how the twisties are more backswept than the standards...
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i like the non twisty look better.
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Thanks for the info Luckie! Now I see the difference. Although maybe a little less attractive, the twisty design still look like they might make a bit more low end torque. I'll have to further investigate that.
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...the twisty design still look like they might make a bit more low end torque. I'll have to further investigate that.
I seriously doubt that 2-1/4 primaries are going to enable much "low end torque" on a BBC regardless whether the tubes are bent this way or that way.
LO
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Literally the only advantage of the twisties over the talls is the increased room you get if you have a bench seat, I sold the standards to get some twisties because of "elbo room"...I hate the smell of burning flesh. :P....
Otherwise, I would be willing to bet they run the same HP wise.... ;)
GT
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I seriously doubt that 2-1/4 primaries are going to enable much "low end torque" on a BBC regardless whether the tubes are bent this way or that way.
LO
Besides, I have never ever seen a jetboat require any "low end" anything.... ;) They don't need much torque at all below about 3000 RPM.
GT
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The other thing to keep in mind is clearance around the headers. If you have a narrow hull like my Hondo you might have problems with anything you choose.
[attachimg=1]
I only have 9" from the rear exhaust port to the inside gunnels :banghead: and with the design of the twisty headers making the rear tube stick out the farthest makes is almost impossible to use on my boat. I just installed a standard set of Bassett BBC jet headers and you can see how close it comes at the third pipe (1" clearance)
[attachimg=2]
I fabricated a set of small heat shields to help keep from burning the gel.
Hope you have a little more room than I do ;)
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The torque thing is just a theory that comes to mind. I have no proof one way or the other. All I know is that no matter which still I choose< they'll make more power over my logs and snails. I haden't thought about clearance. I have a 19' Rogers and I have no idea how it compares in size to a Hondo. I have some grainy pics of when the boat was new and it had Bassetts on it at the time. Hopefully I can figure out what style they were.