Launching a 680HP Big Block Chevy Jet Boat

(Narrator)>> It's not the biggest boat on the water and it's certainly not the most refined, but it makes 680 horsepower, goes almost 80 miles per hour, and puts big grins on our faces when we get behind the wheel. Today on Engine Power "The Lake Missile" takes flight. ♪ ♪

(Pat)>> Today is a day that we have been waiting for for a very long time. Our 1974 Glencoe jet boat is now sporting a brand new 688 horse bullet, and we have been itching to get this chunk of metal flake back out on the lake. And with me is LT. He's playing hooky from Truck Tech. Now LT are you an actual boat guy?

(LT)>> Well you know what I actually grew up on the coast of Maine. I have spent a lot of time in a lobster boat. It's a little bit different than this. This one might be a little bit quicker but I'm excited.

(Pat)>> This is not actually a lobster boat but very close. I'm glad you're along because I'm a bit of an aqua-phobe. I'm a land lover, and the whole thing with that is I'd rather be on land and have something like this on a dyno, but there's no way I'd miss a chance to drop the hammer on this on the lake.

(LT)>> Well you know what? I think you have nothing worry about, we're in good hands. I do have one question for you though. How in the world did you get such a big valve cover on this LS?

(Pat)>> This is not an LS but I appreciate your attempt at levity.

(LT)>> I'm just kidding. I can tell a big block Ford a mile away.

(Pat)>> Oh god! ♪ ♪ The weirdest thing is there's no brakes on this thing.

(LT)>> What'd you say? You want to back up fast and hit the brakes?

(Pat)>> Just don't kill me Clark. ♪ ♪

(LT)>> Can't see the edge of the trailer.

(Pat)>> There's no turning back now.

(LT)>> This is it! ♪ ♪ [ engine idling ] ♪ ♪

(LT)>> All right! [ engine idling ]

(Pat)>> Whether it's in the water or on the asphalt a big block Chevy does one thing. Make whatever it's attached to go really fast.

(LT)>> Oh yeah!

(Pat)>> Hang on, hang on, hang on!

(LT)>> Here we go!

(Pat)>> Ouch, ouch, ouch! This has a totally different feel than a car. Pardon the pun, I'm truly in uncharted waters. It's like riding a horse. You lead it in a certain direction and hope for the best. What's more the throttle affects the steering as much as the steering wheel does. I find myself looking for the brakes but of course there aren't any. I've got to plan my stops well in advance. This thing has a lot of power. On a couple of those runs we were a little bit over 75 miles an hour on the g-p-s.

(LT)>> Moving! You know it makes me a little nervous with how bumpy it is. No handle or anything to hold on to but other than that.

(Pat)>> That's relatively scary in my book, but you want to drive?

(LT)>> Yes!

(Pat)>> Well no better time like the present. Just remember, don't throw me in the drink. I swim like an anvil.

(LT)>> No promises!

(Pat)>> Don't hit nothing cause this thing steers good.

(LT)>> Does the seat adjust?

(Pat)>> The seat does not adjust. Remember this thing has thrust.

(LT)>> Just stab and steer right! [ engine revving ]

(LT)>> The first thing I noticed about this particular boat is how touchy the throttle is. Normally most boats use a hand lever but this one has a foot pedal just like any hot rod and if you're not careful when you're bouncing through the wake you'll give it a little bit more gas than you intended.

(Pat)>> Make some circles.

(LT)>> Even though you've really got to put some muscle into the steering wheel I was impressed with how well this 45 year old jet boat handled the tight turns. In fact it kinda defied my expectations.

(Pat)>> Just clip the throttle here and slow down. ♪ ♪

(LT)>> I'll tell you what Pat. That thing's actually pretty fun to turn around. It'll kinda come up on a curve like that.

(Pat)>> This thing doesn't turn very well at all. ♪ ♪ Well what'd you think?

(LT)>> We didn't die, so.

(Pat)>> I'm very thankful for that actually.

(LT)>> This thing is a blast. I'm really impressed by the response. You just kind of roll into and bah-boo, you're off playing and you're gone! ♪ ♪

(Narrator)>> Up next, we'll show you how the jet boat turns all that horsepower into thrust in the water.

(Pat)>> Welcome back to Engine Power. Today we've got our Glencoe jacuzzi drive jet boat out on Old Hickory Lake in Middle Tennessee. This "Lake Missile" is putting out 329 more horsepower than it did the first time we took it out. We bought this boat from Dwight Brooks, who decided to hang up his captain's hat to spend more time with his grandchildren and work on classic cars. It was in great shape and had a sporty 351 horsepower 454 in the back. We took it out for a quick test run and could tell it had serious potential. We upgraded the big block for another big block chevy. A complete marine crate engine from Blueprint Engines. We couldn't resist putting it on the dyno just to find out how stout this new power plant was. It pumped out 680 horses and 669 pound feet of torque. Before we drop the engine in we wanted to replace the hoses with all new Earl's lines and fittings. No one wants to be stranded out on the water, and Earl's pieces are built for reliable performance in any situation. With this engine turning higher r-p-m, an SFI approved flex plate from Summit provides an extra measure of safety. Once the engine was mounted up we installed MSD's latest marine ignition box, the Six-MThree-L. It's a simple plug and play setup with our MSD distributor, and mounts cleanly to a plate we fabbed up out of 18 gauge aluminum. The Glencoe performed admirably to begin with but you can really feel the difference with the Blueprint engine out back. We call this "The Lake Missile", and with the added acceleration and horsepower it feels like you're powering a rocket heading into orbit. These things are supposed to throw a rooster tail and this is all by the trim right here. So let's see if we can get her to throw a big rooster.

(LT)>> Yeah, play around with it, see what happens. [ engine revving ] ♪ ♪

(Pat)>> We've done plenty of big blocks here on Engine Power but this is the first time we've done one for a jet boat.

(LT)>> So we figured we'd show you guys how this boat turns all that horsepower into thrust on the water. Water is drawn into the jet drive through an intake grate on the bottom of the boat. The impeller is directly coupled with the engine. So if the engine's running it's turning, pulling in water. As r-p-m's increase water is drawn in faster and the impeller forces it into the nozzle at a higher pressure, creating thrust. More engine r-p-m will create more thrust and push the boat faster.

(Pat)>> The reverse gate allows you to control the direction of thrust. With it covering the nozzle it directs water towards the front of the boat, pushing the boat backwards. With it raised the boat moves in a forward direction. Steering is controlled by a cable. The nozzle has a swivel point to steer the boat left and right. The driver can also control the trim. This is done via a hydraulic cylinder that is attached to the nozzle. It moves the nozzle up and down to control the bow of the boat during acceleration and cruising.

(LT)>> That's the science behind a jet boat but once you're on the water with the throttle floored intellect turns into one emotion, pure primal joy. ♪ ♪

(Pat)>> This thing is too much fun.

(LT)>> What do they say? Get you some of that!

(Pat)>> As long as I don't fall out of it I'm fine but man oh man. [ engine revving ]

(Pat)>> This thing basically feels like it's got a really high stall converter in it.

(LT)>> It's great, and the thing's running wide open all day long. Temperature's great, oil pressure's great. I mean what more could you ask for? It's a little thirsty. We're burning through some fuel.

(Pat)>> This is an expensive hobby. So anybody who does this man. I'm not saying I'm converted but I'll tell you what. It couldn't be a prettier day out, and we've got big block horsepower screaming behind us, a big ole rooster tail.

(LT)>> You know what would be cool though.

(Pat)>> What?

(LT)>> Stick a Duramax back there.

(Pat)>> I knew this was gonna go there.

(LT)>> Well we've got about half a tank left wouldn't you say.

(Pat)>> I hope we can actually make it back because we're actually pretty far from where we started.

(LT)>> Do you remember how to get home?

(Pat)>> No, so you're navigating.

(LT)>> I dropped some bread crumbs.

(Pat)>> All right, let's head back. [ engine idling & revving ] ♪ ♪

(Narrator)>> Up next, the Blueprint Chevy big block gets a heavy duty valvetrain assembly.

(Pat)>> Now we're gonna turn our attention to our latest engine build, and its foundation is a Blueprint Engine's 632 cubic inch tall deck short block assembly. Now it incorporates some features that aren't available in OEM applications like provisions for both wet and dry sump oiling, large Siamese cylinder bores, and it has cast end clearance for stroker applications. From their factory it's designed to make over 800 horsepower on pump gas. But since this bullet is going into XOR's Willys wagon and will be turning a huge set of mud tires we need to step up the power to race levels exceeding 1,000 horsepower. The first step was installing a set of Mahle Elite Sportsman series 42cc domed pistons bringing the compression ratio up to an impressive 15.03 to one. The pistons were mated to a set of Eagle forged H-beam connecting rods with an upgraded ARP L-19 bolt. Comp Cam's solid roller cam shaft provides the proper lift and duration for this high performance application. A billet aluminum Jesel belt drive setup keeps the cam timing accurate. Finishing out the front end is an ATI super damper. On the bottom end a Melling high volume oil pump and a seven quart oil pan. Eliza and Jeremy came down from the XOR shop and torqued down the AFR 385cc cylinder heads. These flow 452 c-f-m at 800 thousandths valve lift, and that extra air will help us reach our power goal. Valvetrain components are critical on an engine of this level. So we chose some heavy duty parts, starting off with a set of Comp Cams solid roller lifters. These are from their Elite Sportsman series and they're a tie bar style lifter with an 842 body. The unique thing is they have an offset lifter cup on the intake side to help clear that big 385cc port. Before installing the lifters they are fully lubricated in Royal Purple break in oil. Make sure they slide freely in the lifter bores. ♪ ♪ A little high pressure lube holds the rocker stand shims in place during assembly. The bolts that go through into an intake port are sealed with Permatex thread sealant. The billet steel intake and exhaust rocker stands are different. So make sure they're in the right spot to ensure correct geometry. The stands are torqued to 65 pound feet. With our rocker stands in place it's time to sew up the rest of the valvetrain, and that will start by dropping in some new push rods. We called up Trent Performance and they sent us a set of heavy duty push rods for our application. They are five-sixteenths balls on each end, 135 wall thickness, and their lengths are eight-850 on the intake and nine-900 on the exhaust. Extreme pressure lube is put on both ends of the push rods to prevent wear on initial start up. ♪ ♪ Finally the shaft mounted rocker arms get bolted to the stands. This is a complete Jesel Sportsman series system designed specifically for our AFR head. The intake and exhaust are both one point eight ratio. They are torqued to 28 pound feet. Cold lash is set at 18 thousandths on the intake and 20 thousandths on the exhaust. ♪ ♪ On the induction we needed parts that will compliment what we already have, like a good flowing set of cylinder heads and stable valvetrain. So for the intake manifold we went with an Edelbrock Super Victor Two. Now this is setup to make over 1,000 horsepower on naturally aspirated big cubic inch engines, and it's for a tall deck. 10-200 like our 632. The nice thing is it will take a standard distributor height. No tall deck distributor is needed. No tall deck distributor is needed. It's great out of the box performance and will make big power on a big engine, and on top of that we're gonna be running Holley HP series Ultra Dominator. This one flows 1,475 c-f-m with a two-300 throttle bore, and underneath that to give us more plenum volume we'll be installing a four hole tapered spacer from Wilson Manifolds.

Mahle Motorsports makes it easy to get your bullet together by offering their Power Pack piston kits. Features include Mahle's exclusive Slipper Skirt design which reduces drag and weight but increases strength. A phosphate dry film coating throughout, and their patented Grafal coating reduces friction, wear, and noise. Super accurate ring grooves and hard anodized top ring lands and profiled pin bores are machined on equipment design and built by Mahle themselves to ensure complete control over the quality. The sets also include the correct ring pack and heavy duty wrist pins, and there are a ton of different applications that are available, and to find what you need go to Mahle Motorsports dot com.

(Narrator)>> Up next a crank trigger assembly provides incredibly accurate timing for our big block.

(Pat)>> Today we're building a 632 cubic inch for XOR's Willys Wagon. They requested big horsepower and this power plant will bring it. Now we're talking four digit horsepower numbers here. To keep the manifold gaskets in place during installation we put down a thin bead of Permatex super weather strip adhesive. For an air tight seal between the gasket and the intake manifold we'll use Permatex the right stuff rubber gasket maker. It seals instantly and is resistant to aging, shrinking, and cracking. It also handles continuous heat up to 450 degrees. A nice thick layer along the China rail gives us a tight seal as well. ♪ ♪ Once the intake manifold is carefully lowered into place ARP stainless 12 point bolts will keep it there. ♪ ♪ Super accurate ignition timing is as important as anything else on an engine like this. So instead of running a conventional style distributor we're gonna be running an MSD crank trigger. It's called a flying magnet and it has magnets at every 90 degrees that pass a non-magnetic pick up. It's much more accurate than a conventional distributor. It's more accurate because it has an eight inch diameter compared to the reluctor inside the distributor, which is roughly one and three quarter inches. Simply put the larger diameter yields a finer degree of accuracy. The included bracket can mount on either side of the trigger wheel depending on what accessories you're gonna run. Then the non-magnetic pick up is installed. MSD recommends that the gap between the pickup and the wheel is 50 thousandths. ♪ ♪ We're using an MSD low profile crank trigger specific distributor. There are no connections needed aside from the spark plug wires and the coil wire. The crank trigger handles the rest. We're using Fel Pro steel core gaskets, which have a silicone outer layer and compression stops to prevent overtightening. Next we needed a rigid valve cover because we plan on pulling some vacuum on the crank case. So we opted for a set of Summit racing polished cast aluminum valve covers. We'll cinch them down with more ARP hardware. Moroso billet breathers are built specifically for use with a crank case evacuation system. Hoses will run from them to the headers in our dyno. ♪ ♪ Like I like to say, we are dangerously close to getting this engine running on the dyno and there a few other parts we have to put on, like the carb, water pump, and such. And you're gonna have to wait until next time for that. Plus there are some things we want to try on this engine to help maximize its performance. For more information on anything you've seen on today's show go over to Powernation TV dot com. ♪ ♪ Recently we discussed compression ratio and how it effects performance. Today we are gonna show you how to calculate compression ratio for your own power plant. To determine compression ratio we must make five volume measurements. To keep things organized we'll record each one on a sheet. We'll start with the cylinder volume at b-d-c. Since we know the bore is four-125 and the stroke is four inch we just plugged them into the equation for the volume of the cylinder. Point seven-eight-five-four, times bore squared, times the stroke, times 16.39. This equation converts the result from cubic inches to cubic centiliters. We do this because our equipment is designed to measure in metric volumes. Our result is 876.15 centiliters. The second measurement is combustion chamber volume. Most manufacturers will list this on their spec sheet but if there's any doubt you can measure it yourself. With the valves installed as well as the correct spark plug a clear acrylic plate is sealed over the combustion chamber with a little bit of engine assembly lube. With the barrette in place over the hole in the plate it is precisely filled to 100cc. Then it's slowly drained into the chamber until the chamber is full with no air bubbles. And look at that? We'll check the reading on the barrette. Our result is 69cc. The third measurement is head gasket volume. The manufacturer will provide the bore and compressed thickness of the gasket, and will use those numbers much like we did when measuring the cylinder volume. With a four-200 bore and 40 thousandths compressed thickness this yields a gasket volume of nine point zero-eight c-c's. The fourth measurement is cylinder volume at t-d-c. This measurement assumes a perfectly flat piston with no dome or dish. The LS we use has a piston depth of five thousandths in the hole, and we'll plug that number into our volume equation. The result is one point one-zero c-c's. The final measurement is piston top volume. Now if it had a dome it would take away volume, or if it had dish or valve reliefs it would add volume, but since our LS piston was completely flat we don't need to make this measurement. But if it was not we would measure it the same way we would measure a combustion chamber. With all five volumes known simply add them together. This is the total volume at b-d-c and is the numerator in our equation. Next take the same number and subtract volume one from it. The result is the volume at t-d-c and it becomes the denominator in our equation. Now divide these numbers and you have the compression ratio for your engine. Ours is 12.06 to one. It takes a little time to measure and calculate this value but it is crucial when planning any engine build.