L89 427 Big Block Engine Build - Eagle Crankshaft & JE Pistons

L89 427 Big Block Engine Build Long Block Complete

Typically, the engine build-ups we do here at Super Chevy are more about the recipe and less about the procedure on how to actually build the engine. We do this because the assumption is most of you readers are seasoned builders who know how to assemble an engine (or the person putting together your motor will). We figured it was time to go into more detail on how to build the actual engine before we put it up on the dyno to see how our combination works.

Our idea is to take a very iconic motor, the L89 427 big-block, but build it with new, modern parts. No junkyard or swap meet stuff for this build-everything will be new but still retain the visual essence once you pop the hood. We know that a 427 is pretty small in today's sea of 500-inch-plus monsters, but since we are using a Dart Big M block, the motor can and most likely will be expanded to 632ci with some machine work and a new rotating assembly.

Like we mentioned, the foundation for this build is Dart's Big M block that features some cool stuff. The block is casted out of Class-32 high-nickel iron, which is stronger than the iron used in the stock blocks. It has 4-bolt ductile iron main caps with the option of billet steel for the 1,000-plus horsepower guys. The coolest feature of the block, in our eyes, is the redesigned oiling system. Instead of oiling the cam first like the stock blocks, Dart reconfigured all the oil passages and sends it to the crank first then up to the top end. This keeps the most critical part of the engine-the mains and rods, with oil.

To cap the iron block, we picked up a set of Dart's 275cc Oval Port Pro 1 aluminum heads that have many years of R&D integrated in. The heads are cast from virgin 355-T61 aerospace alloy and have a small, high-velocity port design, raised exhaust ports, improved spark plug location to produce great flow for low- and mid-range power, while still being able to breath on the big end. Plus, the Pro 1s can be used with off the shelf pistons, valvetrain components and intake manifolds.

Inside, will be a rotating assembly consisting of a crank and rod set from Eagle and JE pistons. We want this thing to sound like a street killer so we decided to test out the Big Mutha' Thumpr cam from Comp Cams for an extremely aggressive idle. There will be a lot more parts used to get this thing running, but we'll cover that next month when show how to outfit a long-block, properly break it in, and then dyno tune it. So make sure to come back next month to see how much oomph our L89 V2.0 engine produces.

To get the skinny on what goes into blueprinting, we took all our parts to Speed-O-Motive in West Covina, California. Speed-O-Motive is a full-service machine and speed shop so it has the ability to do anything we need to this engine.

The crew took us through the entire process of getting all these components correctly installed and now we are going to pass that knowledge on to you.

Hopefully you'll be able to use these checks and procedures on your next engine build or at least know what you are paying for when you have a shop blueprint your stuff.

The first step was to have the rotating assembly set to zero balance so the engine will rev nice and smooth. We had Hines Industries, the company that actually makes the balancing equipment, take our Eagle crankshaft,...
The first step was to have the rotating assembly set to zero balance so the engine will re
...Eagle I-beam rods, JE pistons, pins and rings and balance them.
Dart sends the block with a 4.250 bore that has a nice crosshatch finish. Each bore is still checked with a dial bore gauge. This measurement will let us know the piston-to-cylinder clearance and also check the consistency of the bore sizes. We have 0.0050 piston-to-wall clearance, which is right in the middle of JE's 0.0045-0.0055 recommended range for a nitrous application. Hey, juice happens.
Dart sends the block with a 4.250 bore that has a nice crosshatch finish. Each bore is sti

With all the bores checked and good to go, our technician for the day, Chuck Seib, moved onto setting the ring gaps. He slipped in the top ring and squared it with a bore insert before checking the end gap with a feeler gauge. Look to your ring supplier for proper ring gaps. Ours are from JE and they provide a formula to determine the proper gap for just about any application you are putting together like High Performance street/strip, Street Moderate, Nitrous, and so forth. We went with the Nitrous formula.
With all the bores checked and good to go, our technician for the day, Chuck Seib, moved o
Chuck ground the top ring until he had a 0.026 gap and 0.023 on the second. These gaps are a little larger then a normal street engine that would be around 0.019 and 0.020 because we are going to throw some funny gas at this thing and we need the extra clearance for the added heat expansion the nitrous will induce.
Chuck ground the top ring until he had a 0.026 gap and 0.023 on the second. These gaps are
After the ring gaps were ground Chuck slipped on the rings and staggers each end gap away from each other. There will be a diagram of this staggering provided with your pistons. To get the rings on the pistons Chuck placed the open ends in the ring groove first and then spreads the ring open as he pushes it down. This prevents the sharp point on the end of the ring from gouging the piston. That completes the pistons for now.
After the ring gaps were ground Chuck slipped on the rings and staggers each end gap away

Now with the main caps bolted on the torqued to spec Chuck mic'd the main journals.
This measurement will let us know what bearings we need once we compare it to the cranks journal size.
This measurement will let us know what bearings we need once we compare it to the cranks j
Bearings typically come in three different sizes in standard, 0.001-inch under (-1) and over (1X) sizes. We found that we needed standard bearings for our mains to give us 0.0025 inches of oil clearance, which we determined by subtracting the crank journal measurement from the main caps measurement. If we had less clearance we could use a -1 bearing that would give us 0.001 more clearance and just the opposite if we used the 1X bearing.
Bearings typically come in three different sizes in standard, 0.001-inch under (-1) and ov

Chuck is going to set the crank in so we can install a piston at each corner to check deck height. Before that all bearing surfaces are coated with assembly lube.
Chuck is going to set the crank in so we can install a piston at each corner to check deck
After carefully setting the crank in place Chuck torques the main caps from the center out.
After carefully setting the crank in place Chuck torques the main caps from the center out
Chuck uses a tapered ring compressor and the handle of a dead blow hammer to install the number 1, 2, 7, and 8 pistons. Once the piston is in a little bit he reaches back with his left hand and guides the rod over the crank.
Chuck uses a tapered ring compressor and the handle of a dead blow hammer to install the n

Then the rod cap is installed and torqued to spec.
Now each piston is brought up to TDC and the distance from deck to the piston is measured with a dial indicator. We found our pistons were 0.0010 down in the hole, which some builders would run. Speed-O-Motive likes to put the race engines at a zero deck. We asked Jeffrey Strech shop foreman/lead cylinder head/engine designer to explain the benefits of the zero deck and here is what he said. "We set this motor to a zero deck height because it will provide us with the optimum quench distance of 0.040. So when the piston comes up to TDC the quench area, or flat area of the piston and head, compresses the air fuel mixture and sends it at high velocity throughout the combustion chamber. This movement tends to cool hot spots, suppress detonation and increase power."
Now each piston is brought up to TDC and the distance from deck to the piston is measured
All the components were removed from the block and it was chucked into one of Speed-O-Motive's machines to shave off 0.0010 from the block. After the machining process was done, the block was put into a heated parts washer to remove any metal shavings or dirt. Then Chuck put the crank and the rest of the rotating assembly together for good.
All the components were removed from the block and it was chucked into one of Speed-O-Moti

Now its time for the valvetrain. Chuck coated our Big Mutha' Thumpr cam we got from Comp with assembly lube...
Now its time for the valvetrain. Chuck coated our Big Mutha' Thumpr cam we got from Comp w
...and carefully slipped it into the block. Then he spun the cam to see if it turns nice and easy, which it did. If there is a hard spot in the rotation then there is an issue with either the cam being bent, the cam journals not in line or the cam bearings.
...and carefully slipped it into the block. Then he spun the cam to see if it turns nice a
Now Chuck installs Comp's full billet timing chain straight up for now. The crank sprocket has 9 different keyways for 2-degree incremental adjustability, 8-degree maximum advance/retard of the cam.
Now Chuck installs Comp's full billet timing chain straight up for now. The crank sprocket

Now with a degree wheel on the crank, a dial indicator on the piston, and one on the lifter he degrees the camshaft. The purpose of degreeing a camshaft is to ensure that it is phased correctly with the crank. Cam degreeing is a full story on its own and not something we can explain in one caption. Comp offers a full degreeing kit that has a DVD dedicated to this process if you really want to know the full story.
Now with a degree wheel on the crank, a dial indicator on the piston, and one on the lifte
Another good reason to have a professional shop blueprint your engine is it will have all the little things that are usually forgotten, like these locating pins for the heads. Try finding a set of those on a late night in your garage.
Another good reason to have a professional shop blueprint your engine is it will have all
Now we moved onto the heads that were preassembled by Dart. We provided our cam specs when ordering so we already have the right springs keepers and retainers. Still to be safe things need to be checked like seat pressure and coil bind. Jeff removed one spring and replaced it with this gauge. This will tell us the installed height.
Now we moved onto the heads that were preassembled by Dart. We provided our cam specs when

With that information and the lift of the cam Jeff compressed the spring to the install height measurement. Then the scale below his tool tells him the seat pressure, which is 150 pounds. Then he compresses the spring to full lift to check to make sure the spring is not coil binding. We still had some clearance between the coils so we are good to go. As with all blueprinting jobs Jeff checked each valve.
With that information and the lift of the cam Jeff compressed the spring to the install he
When bolting on a head you want to use a good moly lube like the one ARP supplies with its bolts. Put it on the threads and on the flange of the bolt and the washer to minimize friction at these points and provide a more consistent torque setting.
When bolting on a head you want to use a good moly lube like the one ARP supplies with its
Now Chuck checks the camshaft endplay, which is the distance the cam can move fore and aft. One danger with significant cam endplay is the possibility of a roller lifter contacting an adjoining lobe. With the front timing cover installed Chuck moved the cam back until it stopped and forward until it stopped and wrote down this measurement.
Now Chuck checks the camshaft endplay, which is the distance the cam can move fore and aft

The spec is to keep camshaft movement to around 0.005-0.010 inch. Knowing the distance he had Chuck grabbed this roller-bearing cam button. This style button uses an internal roller bearing that does not wear into the timing-chain cover and has small shims that will allow us to set the endplay within spec. Chuck stated that our flimsy stock timing chain cover would deflect a bit. We'll need to buy a water pump that has an adjustable stop on the back to counter act this issue without having to reset the endplay if we changed to a different cover.
The spec is to keep camshaft movement to around 0.005-0.010 inch. Knowing the distance he
Now its time to figure out pushrod length by first installing the lifters, studs and guide plates.
Now its time to figure out pushrod length by first installing the lifters, studs and guide
Because there are so many variations in deck heights and head designs there is no standard pushrod length when you are working with aftermarket stuff.
Because there are so many variations in deck heights and head designs there is no standard

Now Chuck grabbed a handful of assorted length 3/8-inch pushrods and installed the very cool Ultra Pro Magnum rocker arms from Comp. The pushrod length determines where the tip of the rocker arm hits the tip of the valve. Ideally you want it to fall just above center because when the arm starts to push down on the valve it move forward just slightly. After swapping in a few different sets Chuck had the right sizes, 7.900-inch for the intake and 8.800 for the exhaust.
Now Chuck grabbed a handful of assorted length 3/8-inch pushrods and installed the very co
Some blue marking compound on the tip of the valve will show you exactly where the contact patch is. As you can see Chuck got us perfect. Some companies offer an adjustable pushrod so you don't need and assortment. Just put it in, adjust it to the right length, and then measure so you know what lengths to order.
Some blue marking compound on the tip of the valve will show you exactly where the contact
It's time to seal up the bottom end. After an oil pump rod was dropped in the hole, Chuck mounted up our billet spur gear oil pump from Moroso. This monster is a standard volume pump made form a 061-T6 billet housing with three times larger mounting boss area to prevent breaking and it weights 1 pound less than stock oil pump with pick-up.
It's time to seal up the bottom end. After an oil pump rod was dropped in the hole, Chuck

Chuck put a blob of clay into a small bag and set it right on top of the oil pump. Then he installed the Moroso pan with gasket to make sure the pick up was the proper distance from the floor of the pan.
Chuck put a blob of clay into a small bag and set it right on top of the oil pump. Then he
The pan will crush the clay and show you exactly the distance you have. Basically, you don't want the oil pump to be touching the floor of the pan nor do you want it to be more than a 1/2-inch away. We were a little under the 1/2-inch spec so we reinstalled the pan for good. With that, the long block was complete and ready for phase two. We'll go into more detail about our recipe, how to install things like an intake and ignition system, properly break in the motor and how to make adjustments for max power next month.
The pan will crush the clay and show you exactly the distance you have. Basically, you don

SOURCES
Comp Cams 3406 Democrat Road Memphis TN 38118 800-999-0853 www.compcams.com	Dart Machinery 353 Oliver Street Troy MI 48084 248-362-1188 www.dartheads.com
Hines Industries 793 Airport Boulevard Ann Arbor MI 48108 734-769-2300 www.hinesindustries.com	Moroso 80 Carter Drive Guilford CT 06437 203-453-6571 www.moroso.com
Speed-O-Motive 131 North Lang Avenue West Covina CA 91790 626-869-0270 www.speedomotive.com	JE Pistons 15312 Connector Lane Huntington Beach CA 92649 714-898-9763 www.jepistons.com
Eagle Specialty Products, Inc. 8530 Aaron Lane Southaven MS 38671 662-796-7373 www.eaglerod.com