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Lightning or GiL

Old 09-11-2016, 10:27 PM
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Question Lightning or GiL

Pulling my motors for paint, going to invest in some exhaust, heads, cams...

Going dry tails for more aggressive cam profile.

Some people say GiL, some say lightning...

I only run once a year in salt water and flush immediately.

Please LMK your thoughts and why!

Thank You
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Old 09-11-2016, 10:34 PM
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In order to run Lightnings with dry tails I'm pretty sure you're going to have to have them custom made, so they are going to need to be new. Gils you can find with dry pipes pretty easily. As far as performance goes, there will be zero difference between the two. One thing to consider, aluminum manifolds are more reliable than a tubular style exhaust. Also lightings are not headers, in order to qualify as a true header the runners need to be at least 26", if I am remembering correctly. I would look at Stainless Marine- IMO they have the best design and are affordable, durable, and produce good power.
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Old 09-11-2016, 11:11 PM
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Here you can see where on a 500hp engine, the gils gave up 30ft lbs of torque , and 15hp or so to a set of CMI headers. That was onna 500hp engine. If youre intending on making more power than that, and going with a cam that actually can take advantage of scavenging , you might find a more substantial difference.

Then you get into header design, tube length, and primary diameter. There lies quite a bit of power in a big block exhaust setup, especially as the engines breathing capabilities increase.

Manifold wise, my choice would be the old eickert ones . Headers, cmi are great but of course pricey. The lightnings are a great piece, and they now offer big tubes and dry tail options as well.
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Old 09-11-2016, 11:32 PM
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The old eickert design that diamond now sells have long enough primaries to be considered headers I believe. - just looked it up, they say 32 inch runners.
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Old 09-12-2016, 06:54 AM
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I went to KEperf.com and I'm not seeing there headers?
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Old 09-12-2016, 07:03 AM
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These are the old eickerts

http://www.diamondperformanceparts.c...cat=282&page=1
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Old 09-12-2016, 07:10 AM
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If you have 24* cylinder heads it's a nightmare to change plugs with Gil's sometimes you end up having to re-move or loosen the exhaust to get the plugs out. The Gils also end up running into stock Alternator brackets/ alternator and have to grind on the manifold to get them to fit. For these reasons I would steer clear of the Gils. A lot better options for marine exhaust this day and age...
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Old 09-12-2016, 07:52 AM
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Eickerts are the best out there for both power and reliability, I ran them on one of my engines and gained around 2 mph with them compared to Stainless Marines. However I was spinning my engines to 5900, so they were taking advantage of the scavenging ability of this design. My midrange also improved. Good luck finding them used! I've been looking for 3 years, which is why I did not mention them. New I think their around $3600 with wet tails, dry would be more.

I was recently thinking about going to CMI sport tubes. I called a friend of mine that builds a lot of big HP engines in NC. He said that every single blower motor they have built and put CMI's on, they loose power on the dyno. That is comparing the same engine and swapping to Stainless Marine Gen III manifolds. The biggest issue with tubular exhaust is they will eventually leak. Over the years I've bought several sets of CMI's. Always told, no leaks, only to test them and have them leak. I have no experience with Lightnings, but there are many posts on here about guys going from Gil's to Lightnings and they gained zero. Maybe on a dyno there is some difference but not in a boat.

As Black Baja said, changing the plugs with Gils does suck. I've got Dart Pro 1's on my boat and it took me 2 hours to change the plugs on one engine. I don't think Eickerts would be any easier. The Stainless Marines are way easier due to the fact that you don't have to work around a water distribution tube under the manifold. The SM's are wide open, there is nothing below the manifold. What he also said about the alternator is true. I had very little room for adjustment. Mine ended up fitting fine but it is tight.
Stainless Marine's are pretty bomb proof and pretty easy to come by, so are Gil's but I feel Stainless Marine's are better.
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Old 09-12-2016, 08:11 AM
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For a big blown engine, give me the stainless marine GEN 3 manifolds anyday. Most marine tubular headers, are too small for big blown stuff. When youre building a 6000rpm big blown combo, those 1 7/8 primary and even 2" primary headers dont cut it. There could be a big difference on a 1000hp blown engine, with some basic cmi e tops, and cmi big tubes.

I dynoed my engine's the first time around with 2.25 inch primary id car headers with a 4 inch collector going into huge flex pipes that were like 8 inch. ..then dynoed at a different shop this year, with my stellings headers, which are 1 7/8, had my stellings tails that choke down to 3.5" tube, along with my sea pump, alternator, etc.

I was worried, becauase when putting the dyno sheets side by side, the new setup showed about 20 less hp, and alot less torque.

But, when installed in the boat, even after adding a few hundred pounds on the stern, adding another pickup on my transom, the boat is quite a bit faster.
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Old 09-12-2016, 08:50 AM
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Definately not a blown motor, just heads/cam forged 454.
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