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-   -   Kieth Eckert Manifolds make more power than CMI Headers (https://www.offshoreonly.com/forums/general-q/149756-kieth-eckert-manifolds-make-more-power-than-cmi-headers.html)

rexone 01-25-2007 07:51 AM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 

Originally Posted by saxman (Post 2004187)
Here is a cutaway pic of when I made the headers. They are all 31 to 32 inches in length with a 4 into 2 into 1 collector.
Typically it performed like any good 2 X 32 header with frequently a little extra torque around 3600 to 4400 rpm because the 4-2-1 collectors which typically broaden the torque band. The runners actually have an oval profile with an area equal to a 2" round header. Currently we are using them on 1250 HP motors.
Dennis

Hello Dennis, how you doing :)

bcarpman 01-25-2007 02:50 PM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 

Originally Posted by rexone (Post 2004330)
As a manufacturer of many stainless parts including a lot of 316L tube products (not headers) I can tell you with confidence you are way off base on your cost estimate. You can't even purchase the material for a set of headers for that amount of $ much less the labor to bend, weld, polish, R&D, equip cost, etc etc etc... Not saying Merc isn't high priced, they are. But no where near that level of markup exists in any of this stuff.

Yeah, I was thinking more about that after I wrote it. I guess it really just depends on the amount made. I know about what it costs to make custom SS single wall headers, and know how cheaply they can actually be produced if you're getting them made in reasonable sized batches, but I guess I really don't have any clue how many sets of headers CMI makes or MR buys. Is it 10 a year or 500? If they're making them in decent sized batched, you can setup the benders and crank them out pretty quickly. Of course welding up the double walls has to be interesting. All the more reason for others to step up and make KE style cast aluminum headers.

Rage 01-26-2007 01:06 PM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 
I had occasion to talk to a race program individual that stated some years back they tested every header package that they could get their hands on and found that the CMI's produced the best hp. They also tried the KE cast manifold which worked well producing hp but experienced "cracking" of the internal cast runners and hydrauliced a motor as a result. Since reliability was a top priority they dropped future consideration of the KE manifold.

cougarman 01-26-2007 02:26 PM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 

Originally Posted by Rage (Post 2006107)
I had occasion to talk to a race program individual that stated some years back they tested every header package that they could get their hands on and found that the CMI's produced the best hp. They also tried the KE cast manifold which worked well producing hp but experienced "cracking" of the internal cast runners and hydrauliced a motor as a result. Since reliability was a top priority they dropped future consideration of the KE manifold.


Interesting, I heard some other reasons ??
Guess what they use it over Sea's in there racing circuit. :D

Cougarman

James 01-26-2007 05:05 PM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 
The cast aluminum manifolds are no more likely to melt than aluminum heads or aluminum pistons, assuming they have proper cooling. Stopping water flow to either the SS or cast manifolds under high load conditions can result in failure.

For the people who swear by the stainless exhaust and say they never leak probably have never had them off and pressure tested them with 30 psi to prove weather they leak or not. And for those who have hydroed and engine - well those guys already know they leak.

I know from experience that a quality SS manifold is relatively low risk item, however my personal experience is that aluminum is less likely to fail all things being equal.

bob 01-26-2007 09:38 PM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 
Rage, interesting comment as I had good inside info that Merc had made offers to KE to purchase his pipes. KE opted not to go there. I have over 400 hours on a pair and I have run at least 750 hp into them and for the last 200 hours over 900. Not a single issue. However, I do keep them supplied with water to keep them properly cooled.

Rage 01-27-2007 01:16 AM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 

Originally Posted by bob (Post 2006705)
Rage, interesting comment as I had good inside info that Merc had made offers to KE to purchase his pipes. KE opted not to go there. I have over 400 hours on a pair and I have run at least 750 hp into them and for the last 200 hours over 900. Not a single issue. However, I do keep them supplied with water to keep them properly cooled.

All I can say is this what I was told was from a reliable source. Maybe just bad luck or like you say cooling problems. Sounds like others are racing the KE with success and reliability. Of course I have also seen similar conflicting comments on the CMI's. Some say they have never had a problem and others say the can not keep them on the boat. Seems like more are reporting problems than not. I was personnally planning on purchasing the KE until I discovered that they do not make one for the 496 and have no plans to.

An addenum, I asked KE if they still Extrude Hone the tubes. They do not.

Annother comment on why Mercury is using CMI's is maybe they make the most hp.

Rage 01-27-2007 01:23 AM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 

Originally Posted by cougarman (Post 2006208)
Interesting, I heard some other reasons ??
Guess what they use it over Sea's in there racing circuit. :D

Cougarman

What " other reasons"?

cougarman 01-27-2007 03:48 AM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 

Originally Posted by Rage (Post 2006807)
What " other reasons"?


Perhaps all I should say is the European Teams love them. :drink:


Cougarman

BGIII 01-27-2007 09:01 AM

Re: Kieth Eckert Manifolds make more power than CMI Headers
 

Originally Posted by Rage (Post 2006805)
Another comment on why Mercury is using CMI's is maybe they make the most hp.

If that is the case, then why would they use Edelbrock heads? We all know that they are not the best available.

525-550 horsepower is not rocket science. They are buying what makes the boat look faster/better and what they can get the best deal on. With the outrageous prices Mercury Racing charges for their product, it has to look like it is different or better than regular Mercury product. I don't think a guy that is willing to pay 300-500k for a boat w/ 525's and goes as far as to have airbrushed battery hold downs, wants a big old clunky set of KE's under the hatch. It doesn't matter how much horsepower, how good or how reliable they are. I do know that if I had a set of 525's in a 3 year old boat and needed to buy $10,000 worth of new headers because they were leaking, I would be the most pissed off guy on the internet.


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