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-   -   Made in China BBC headers any good? (https://www.offshoreonly.com/forums/do-yourself-boating-budget/324264-made-china-bbc-headers-any-good.html)

thirdchildhood 03-26-2015 04:42 PM


Originally Posted by getrdunn (Post 4284255)
Wtf. Kinda interesting to say the least.

Could be why headers are failing. The one with the heaviest tail-pipe is really flexing right at the head. Maybe engines with long tails should have a bracket fabricated to tie the collector area directly to the engine. Starboard engine is flexing a lot too. Is that normal with rubber mounts?

SB 03-26-2015 04:44 PM


Originally Posted by COOPS (Post 4283874)
After seeing this video I cant believe that headers don't fail all the time. Manifolds seem to be the most durable construction.

http://youtu.be/Fin2S42e_5M

Yup. More guys should get their tubes tied. Ha ! LOL.

airjunky 03-26-2015 10:44 PM

Hopefully the guy who rigged the cover didnt bolt up the starboard engine plates . But im thinking he did

thirdchildhood 03-27-2015 05:51 AM

That boat should have solid, off-shore engine mount plates, right? Or does it have normal rubber mounts? That one header rocking like that will crack for sure. Then someone will be blaming Merc or CMI. Why not clamp a bracket onto the front of the tail and bolt some kind of tie bar directly to the engine? I would do that if I saw that on my boat.

ivanfuego 03-31-2015 08:41 AM

Yes I'm in salt water, but even in fresh water I wouldn't want to go with these "injected" headers as I would be injecting water right into my cylinders! I didn't notice that part and thought they were jacketed like the stellings.

As for the Stellings, I have found a few selling used sets at decent prices (some needing repairs some not). But I now find myself wondering if these are a good fit for my app. I honestly like the bling as the little horsepower increase I'm sure I can get from any performance exhaust.

SB 03-31-2015 08:53 AM


Originally Posted by thirdchildhood (Post 4284497)
Why not clamp a bracket onto the front of the tail and bolt some kind of tie bar directly to the engine? I would do that if I saw that on my boat.

I've always wondered the same. They make/use them on jet boats / V drives.

http://shopping.rexmar.com/Merchant2...001/128140.jpg

burn504 05-10-2015 10:46 AM


Originally Posted by ivanfuego (Post 4286177)
Yes I'm in salt water, but even in fresh water I wouldn't want to go with these "injected" headers as I would be injecting water right into my cylinders! I didn't notice that part and thought they were jacketed like the stellings.

As for the Stellings, I have found a few selling used sets at decent prices (some needing repairs some not). But I now find myself wondering if these are a good fit for my app. I honestly like the bling as the little horsepower increase I'm sure I can get from any performance exhaust.



you must have a ****ty engine if injecting into your exhaust goes into your cylinder. The valves are closed unless exhaust gas is going out. The velocity of the collector would pull any water being injected into a cylinder not firing.. not to mention the cylinders are firing many many times per minute.

I would think water injected through transom without being under a hatch would be just fine. Under hatch probably not he best idea..

Also someone said they are injected at collector which you can see isn't true. With the right water regulation it should stay relatively cool. There was another post on another forum with many people running them (not under hatch) and seemed fine.

dwiddowmaker 05-10-2015 03:32 PM


Originally Posted by burn504 (Post 4302607)
you must have a ****ty engine if injecting into your exhaust goes into your cylinder. The valves are closed unless exhaust gas is going out. The velocity of the collector would pull any water being injected into a cylinder not firing.. not to mention the cylinders are firing many many times per minute.

I would think water injected through transom without being under a hatch would be just fine. Under hatch probably not he best idea..

Also someone said they are injected at collector which you can see isn't true. With the right water regulation it should stay relatively cool. There was another post on another forum with many people running them (not under hatch) and seemed fine.

You've been dormant for 5 years, and I hope after this post dormant for another 5 years.

Not only does he HAVE to run water jacketed headers or manifolds in his Outlaw, but your comment about the exhaust valve ONLY being open when exhaust is being pushed out is completely untrue. Overlap allows the exhaust valve to remain open briefly at the end of the exhaust stroke, as the intake valve opens and the intake stroke begins. Both duration and separation have a direct effect on the amount of overlap, and typically the more aggressive the N/A cam, the more overlap there will be. This is what causes reversion.

Do some studying on valve event timing before some poor soul takes your ill advice as fact please.


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