454/496 build for Glen-L rampage

Hi everyone,

First time poster here - I've been working on a Glen-L rampage for a few years now and am finally ready to get some iron in it! Apologies if you see this exact same post on similar forums...I'm trying to cover my bases, of course. I have also done some extensive searching on this forum and others to get an idea of everything, but I'd rather get some specific feedback on my application / thoughts before I pull the trigger, if that makes sense.

Some quick background - it's a 20', 1000lb hull, with an SD-309, performance intake (shoe/ride plate), and AA impeller. See below pics on current progress. I'm pretty committed to a 454/496 - I know, I know, a ford or olds will be better to half of you, but I'm a chevy guy and already own chevy mounts / accessories. Lightning water jacketed headers as I can't run twisties on my lake, and I'd like the build to spin my pump at 5k for the next ten years on pump gas without worry...so a dead nuts reliable 550 hp is what I'm looking for. Experience wise this is my first V8 build, but not my first engine and as a mechanical engineer by training I should be a pretty quick learner.

Here's what I'm thinking so far:

-454 block, 4 bolt mains, junkyard.
-Eagle or Scat stroker kit - scat only offers a 489 but if they're head and shoulders over eagle I don't mind loosing 7 ci.
-AFR or Brodix aluminium oval port heads, ~275 cc runner volume, with chamber matched to above pistons to get me around 9.5 - 10:1 CR
-Victor Jr or RPM Air Gap intake
-Holley 850 Double Pumper - likely the marine version as it's a wooden boat and I'd rather be safe than sorry, though the engine is definitely sitting loud and proud in the open.

Notably absent of course is my cam choice...I'm pretty dead set on a hydraulic roller and I need to worry about reversion from the wet exhaust (water *jacketed*, not injected, but the water ends up in the pipe down stream anyways)...otherwise I am all ears!

Please tear me to shreds and tell me I'm out to lunch - I'm not here to feel good about myself, I'm here to learn. And of course, if you guys have any questions or want to see more pics, just ask - and otherwise thank you all very much for the help!

Cheers,

Denon

https://scontent-ort2-2.xx.fbcdn.net...cd&oe=5AD5AD92
Overall hull, sanded and waiting for another coat of epoxy / varnish. That's a fake / foam block for mocking things in place.

https://scontent-ort2-2.xx.fbcdn.net...73&oe=5A9DC9EE
View from the rear.

https://scontent-ort2-2.xx.fbcdn.net...47&oe=5A8ED629
https://scontent-ort2-2.xx.fbcdn.net...6a&oe=5A8FD9B2
The camera does a terrible job of picking it up, but the boat's not black at all - it's just stained mahagony that the camera can't pick up.

Welcome to www.hotboat.com I’m sure someone with know how will chime in soon


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Great project man, I'm a Vdrive guy so absolutely no help on the jet aspect but I just built a 489 for my day cruiser, the difference between the 489 and 496 is going 30 or 60 over, since I had a clean block I opted to just take 30 out of it just in case I hurt it down the road. I would go all forged and let her rip, look forward to seeing you finish this off.

More pics, that boat is bad ass


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Hey all,

Apologies for my 4 month delay - I never got notifications through e-mail for some reason. See attached pics - I haven't made any progress at all since the last post as my shop is on an island that's inaccessible in the winter (and I've been too busy snowmobiling anyways!).

As requested, here's some more pics - hopefully will have the hull finished in the next few months (ice should be out in a few weeks). Still torn on the engine...Not sure if it's worth it trying to buy an old beater and rebuild / upgrade or just start from scratch. Any thoughts?

Similarly I've narrowed down my header choices to either basset through transom water *injected* headers, or lightning water *jacketed* headers. It's a wooden boat and I'm terrified of reversion or overly high temperatures, so I'm leaning towards the lightnings pretty heavily...but they're twice the price and don't look nearly as awesome (nevermind the lack of chrome shine).

Here's hoping to a great summer!

EDIT I cannot for the life of me figure out how to upload photos. When I upload from my computer it says "failed" and when I try to use a URL it also says "failed". Unfortunately, that means you'll have to click on the links below - but at least they're good pics!

Front view showing the profile, and before it was stained, showing the wood:
https://www.facebook.com/photo.php?f...5&l=1475a5e8fb
https://scontent.fybz2-2.fna.fbcdn.n...60&oe=5B69376B

Showing how the wood looks in the sunlight...it's dark, but not black!
https://www.facebook.com/photo.php?f...9&l=b298766d7a
https://scontent.fybz2-2.fna.fbcdn.n...8c&oe=5B2E0DB2

View from the rear...
https://www.facebook.com/photo.php?f...9&l=367ba01f9e
https://scontent.fybz2-2.fna.fbcdn.n...f9&oe=5B638AEE


Denon

Well, a quick update on my end...I decided to completely abandon my plan but am still very happy with things turned out.

In short, I came across a Merc 454 Magnum in *amazing* condition for roughly 3k US. Leakdown and compression were like new, and it's a complete motor. It's a 4 bolt, forged everything with 188 heads, decent intake carb and cam - so with a cam swap, a little TLC on the heads, and potentially a new carb and intake, I should be pushing close to 500 hp (it comes in at roughly 400 "as is", so 500 should be pretty eas [ Attachment Invalid Or Does Not Exist ] with the right combo of parts...and the short block is built like a tank so I'm not worried about longevity at that power level). Not quite the plan I had in mind but given the price, condition, effort, and the *sexiest* valve covers I've ever seen...it was just too good to pass up. Plus, having done some number crunching, the boat is actually a bit lighter than expected, and I honestly don't think I'll notice much of a difference between 500 and 550 hp...whereas I will definitely notice the extra few thousand I have lying around to spend on gas!

I'll continue to post updates every few months as I go through the build in case anyone has recommendations, thoughts, etc. In the meantime...pictures!

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