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Has anyone seen dyno numbers for lightning headers posted anywhere? They're about half the price of the CMI's for my 496HO and considering I only boat in fresh water, might not be a bad option. I do not know where the water enters the exhaust on the Lightnings though.


Matt
 

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CMI's are good headders but they seem to have a reputation for failure at welded joints after a while. That can lead to disaster if water is ingested :eek: However, I read somewhere that they will last longer, if properly supported. Who knows :confused:

Although Lightnings don't have full/32 inch primaries, personally I'd chhose the Lightnings over CMI's. Question is, how much more hp/tq would you get with CMI's as opposed to Lightnings. And is it worth the extra cost.

Bang for the buck, I think KE's are the best choice ;)
 

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I doubt the extra cost of the CMI's are going to yield any more hp than the lightnings.

As for your question about where the water enters the lightnings, its the same as the CMI's and many others, throught the bottom.
 

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Don't get your hopes too high. My CMIs added MAYBE 1/2 mph. No way did they add 40+ hp to a stock 496 HO. Also the Q&Q kit is poorly engineered and will work only at idle without mods. With mods mine is still only good in quiet mode to 3,500 rpm. That said, I don't regret dropping the 5g on the best headers available because I plan to redo my motor in two years and SC it. Then those headers will do their job. Do you have the factory aluminum exhaust on your 496? If so, it is a very free flowing exhaust system, probably capable of flowing up to the limits of the stock heads. Has anyone seen real speed increases by just bolting on CMIs?
 

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CC said:
Don't get your hopes too high. My CMIs added MAYBE 1/2 mph. No way did they add 40+ hp to a stock 496 HO. Also the Q&Q kit is poorly engineered and will work only at idle without mods. With mods mine is still only good in quiet mode to 3,500 rpm. That said, I don't regret dropping the 5g on the best headers available because I plan to redo my motor in two years and SC it. Then those headers will do their job. Do you have the factory aluminum exhaust on your 496? If so, it is a very free flowing exhaust system, probably capable of flowing up to the limits of the stock heads. Has anyone seen real speed increases by just bolting on CMIs?
Almost a 4MPH Gain in my Sunsation SSX
went up 1 size Prop. Stock Prop Im in the Rev Limiter BAD!
 

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I gained 2-3 mph, and probably ~ 150 rpm. Put me into the rev limiters. Had to do a little prop work, and still just touch the limiters.
 

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I guess the results vary. I had a factory all aluminum exhaust on my HO which the guys at CMI said they'd never seen :confused: , the ports are huge. I still like the CMIs and they are just a first step......... :devious:
 
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