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-   -   CMI headers (https://www.offshoreonly.com/forums/general-q/358484-cmi-headers.html)

ThisIsLivin 01-14-2019 10:55 AM

I have lightning headers on my boat and they are going on 20+ years. I sent them in for testing a while back and I've run my camera down the tubes and they look like new. They have the longest tubes of anything that I have seen. yes they are lightly wider than the cast systems, but the tubes have longer radii than the cast style as well. For the difference in price have them powder coated any color you like. While I haven't personally run a side by side on my engine with other products, there is enough empirical evidence to indicate their design is suited for maximum power. It all depends on your motor setup and where you want the peak performance to occur. I have more low to mid range torque than my bravo can handle already so I'm going for maximum horsepower.

SB 01-14-2019 11:15 AM

Shhhhhh.....The Parvey's designed and sold these first....PF Marine. KE bought the whole deal from them and sold them for many years.... Now, our good man Diamomd Marine bought the whole deal from KE,

If someone doesn;t know the Parvey's, KE, and Diamond...then you need to !!! :)


ACrooks69 01-14-2019 11:27 AM

Well, I know the guy who designed the TnL headers and he did make them for bigger motors. As analytical as that guy is, if he put any effort into them, he did them right, not blingy. I mean he's only running what 165 at the LOTO shootout in a V with a motor package of his design. CMIs are cool though. I'll probably be ditching my EMIs for Lightning on my SBC.

*Edit* SB, didn't see your comment. Right on.

ICDEDPPL 01-14-2019 02:54 PM

Getting rid of Headeraches is thee best thing I`ve done. Don`t miss spending a bunch of time trying to tighten header bolts or seperate the tails either.

Takes about a minute to pull the manifolds. (out of boat )


https://cimg8.ibsrv.net/gimg/www.off...fbd6899e22.jpg

Tinkerer 01-14-2019 07:12 PM

I didn't say that they wouldn't work on a blower engine. I said that I heard they were a little restrictive. Unless they have changed them.

endeavour32 01-15-2019 07:45 AM


Originally Posted by Tinkerer (Post 4668083)
I didn't say that they wouldn't work on a blower engine. I said that I heard they were a little restrictive. Unless they have changed them.

If I remember right they had a 2" runner. So until you get into the really big power blower motors, they are great. Also the collector is 3.5" so a bit of a restriction there as well. However, even the CMI Big tube e-tops only have a 3.5" collector opening, and they are so wide they will not work in a side by side boat. I know, because I tried. Like anything there is no one size fits all header, but the T&L are a great choice. For really big power Stainless Gen IIIs are the ticket, like Dan has.

I was pulling the headers on my engines last night (sport tubes), i will say this, they are so easy to remove. You can work from both sides of the header, you can't do that with a manifold. So they get a thumbs up for bling, and being really easy to work with.

ttrm007 01-19-2019 01:25 PM

https://cimg2.ibsrv.net/gimg/www.off...56c0422536.jpg
I think the lightnings look pretty good and for the price!

Precision 02-10-2019 11:23 AM

Good luck with those! Every engine that I have seen with those have been due to the headers rotting out and water filling the engine.

ACrooks69 02-11-2019 02:14 PM


Originally Posted by Precision (Post 4672035)
Good luck with those! Every engine that I have seen with those have been due to the headers rotting out and water filling the engine.

are you taking about the CMIs or Lightnings with that reference?

Precision 02-11-2019 04:43 PM


Originally Posted by ACrooks69 (Post 4672181)
are you taking about the CMIs or Lightnings with that reference?

Sorry for the confusion. I was referencing the Lightning’s. They all rotted out from the inside.

Tinkerer 02-11-2019 07:46 PM

The new Lightning headers are stainless inside tubes and regular steel outer tubes.

Baja Rooster 02-11-2019 09:39 PM


Originally Posted by Tinkerer (Post 4672222)
The new Lightning headers are stainless inside tubes and regular steel outer tubes.

At least that way the outsides should fail first, yea?

AusScarab29 02-12-2019 02:39 AM


Originally Posted by Precision (Post 4672200)


Sorry for the confusion. I was referencing the Lightning’s. They all rotted out from the inside.

where these the ones with stainless inner tubes and stainless outer tubes or the steel outers

AusScarab29 02-13-2019 04:19 AM


Originally Posted by Tinkerer (Post 4672222)
The new Lightning headers are stainless inside tubes and regular steel outer tubes.

I contacted lighning today ,i was told the salt water versions where 316 stainless inners and outers
Has any one had problems with these?

SABER28 02-13-2019 09:15 PM

i looked at the lightnings,, but the full stainless ones are not that much different in price than the cmi's. those welded together pieces just look like a future failure point to me.

AusScarab29 02-14-2019 04:14 AM


Originally Posted by SABER28 (Post 4672569)
i looked at the lightnings,, but the full stainless ones are not that much different in price than the cmi's. those welded together pieces just look like a future failure point to me.

which CMI headers.

ThisIsLivin 02-15-2019 08:37 AM

Deleted

Coolerman 04-14-2020 03:29 PM

The KE Headers flow equal to about a 2" primary. The primary size needed and runner length needed for a motor is dependent upon a lot of factors such as exhaust port design, cam profile, and compression, but at a certain HP level you just need to get some flow.

If I had a NA motor, the KE would be my #1 choice as it is a 2" primary with a 4-2-1 collector and a full 32" equal runner.

That being said, we ran our KE headers to a solid 1500hp on a supercharged application, but I wouldn't recommend it. 800-1100hp blower motor is a toss up on that or stainless marine. Big HP blower motors I would go with Stainless marine for more flow.


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