Ok – If you’re going to build a 496, this is the way I would approach it. Others will chime in and you can balance all the input and let us know what you opt to do!

Let’s take it from the ground up and assume that you go the U-Pull-It and buy a 454 from a truck – two bolt small port that’s still readily available for about six hundred bucks. I’ve bought several cores from these guys over the last twenty years and they’re good about any issues with cracked heads or broken blocks so you know you’ll get a buildable base. Drag it home and completely disassemble and cart the block and main caps off to a machine shop for a thorough clean and test for integrity. If the machinists say’s it’s good, then have them do all the necessary work, i.e., bore the cylinders to.060” over the stock 4.250” measurement and hone to accept the new 4.310” pistons, square the decks, align bore the crank and camshaft bores and grind necessary clearances for the stroker (4.25”) crank. Have them install new cam bearings, brass freeze plugs and all of the necessary oil galley plugs. Also have the machinist install your new pistons on your new rods (part of the rotating assembly kit). Spend a bit of time with the machinist that will be doing the work and be sure he or she shows you where all the work has been accomplished and where all the plugs are. Be prepared to write a check for at least $1,000 to the machine shop.

While your block is being worked on, buy this book - How to Rebuild Big-Block Chevy Engines: Tom Wilson: 9780895861757: Amazon.com: Books and read it, especially the assembly portions.

Take the block home and bolt to a four caster engine stand. If you don’t have a stand – go to Harbor Freight and buy one – Item #69520, $60. Get a drip pan or a deep cookie sheet to go with the engine stand and secure to the base of the stand - -trust me here, you’ll be glad you did this as you will drop parts and spill liquids in the build and this really aids in the recovery and cleanup. Scrub a dub the block with hot water (I take mine straight from the bottom of the water heater) and Dawn dish soap. Use lots of soap and repeat this until there is absolutely no trace of grease or contamination visible in the rinse water and then do it one more time. Use stiff brushes (Harbor Freight – couple bucks) to make sure you’ve got all the nooks and crannies. Dry the engine block with compressed air – wear goggles please as we do not want to visit the ER. And regardless of any other advice you hear, do not come anywhere near this project with WD-40!

Paint the galley of the block with Glyptal – Eastwood, about $50 a quart and worth every penny. Use the cheap Harbor Freight China bristle disposable 2” brushes 12 bucks for a box of 36. Mask the flat surfaces and bottom of the block and spray paint with VHT engine paint (about $5 a can – get two). While you wait for the paint to dry (at least a day) – re-read the book.

Now the fun begins. Eagle (and others) makes a 496 stroker kit. Summit has them for about $1,600. This is a complete and balanced rotating assembly. Before you start make sure everything is spotlessly clean and that you have a good assembly lube. I like Red Line as I used it for years to build two-stroke race motors. It’s good for anything that moves in the assembly process. As you set the crank, consult the book often and take your time. The crank should move smooth and free. Check it often using a crank turning tool as you snug the mains as per the book.

Piston rings are tricky if you’ve not done them before and they will break. Your rings will come as part of the Eagle kit. Each piston set wrapped in plastic. I recommend opening them one-at-a-time and wiping them down with lacquer thinner and inspecting each one. If you find one that is damaged in any way, don't use it and call for a replacement set. I also very lightly sand all the edges of the rings with 400 emery paper to smooth any rough edges. The rings should fit the cylinder bores perfectly, but it doesn’t hurt to check just to make sure. Use lube and square the ring in the cylinder and measure the end gap. Rule of thumb is .004 inches times the bore diameter for the top piston compression ring (4.310 x .004 = .017) and .005 for the second ring (4.310 x .005 = .022). Go slow installing the rings on the pistons to avoid scratching the pistons. Do all of the pistons at one time before starting to place them in the engine. Use a piece of rubber hose over the rod bolts and check for continued smooth crank rotation after installing each piston. There will be increasing drag as each piston goes in, but there should be no hard or tight spots. Again, use lots of lube, read the book, keep your work area and your hands spotlessly clean and take your time. No alcoholic beverages are allowed during this process – only after you’ve quit for the day!

Before closing the bottom of the engine up, install a new stock volume/pressure oil pump, drive shaft, and pickup – about $125. You’ll need a new oil pan to clear the stroker – Milodon seven quart deep sump is another $250.

I’d also buy complete heads rather than rework used ones. I know others will disagree – but unless you know the heads are perfect cores, they can consume a lot of time and money only to be disappointing in the performance. Summit sells a knock off GM performance cast iron set for about $1,600 that looks pretty good. Get a new set of ARP head bolts - $85 well spent. Note that these heads will require longer pushrods.

Howard Cams part number CL110255-12 is a roller retrofit kit that includes the cam and lifters. Looks to be a good fit here in terms of lift and duration for a streetable engine. Cost is $600. Timing set is another $40. Rocker arms and push rods are probably another $300 – depending on how fancy you want to go. I like roller tips, not roller rockers. Soak the lifters in 50/50 lube engine oil for 24 hours prior to installing them. Do not use any molly grease on the rollers. Read the book for installation help with basic timing to make sure everything opens and closes at the right time.

I like Edelbrock Performer RPM -7562 for this build. About $300. Throw away the funky end gaskets pieces and use black RTV silicone to make a good seal at the ends. I like Gaskacinch for intake manifold to head seal – about five bucks for a small can with the handy dandy brush applicator. The Edelbrock 1411 is a 750cfm vacuum secondary, electric choke unit that should work well out of the box for $350. A Holley 4160 would also be a fine choice for the same money.

Distributor – HEI from MSD (just say, “No!” to anything from Accel). Nice billet unit is about $350. Wires and plugs will add another $65.

Valve covers, front cover, breather air cleaner will set you back $200-$600 depending on how fancy you want to go

Seven quarts of Royal Purple and a filter another $65 and we’re getting pretty close to seeing 500 plus horse power. I built a little spread sheet for this and we’re north of eight thousand with all the bits and pieces. If you go e-bay or swap meet you can save some on the carb and intake as well as the distributor; however, I’m real cautious about heads at a swap meet as they are a crap shoot and unless they’re from a known source with a money back guarantee, they can be expensive boat anchors. If you don’t have some of the necessary tools, i.e., micrometers, torque wrenches, ring compressor, etc., it’s easy to add several hundred to this total.

If you’re still excited about this I’d say, “Go for it!” but you may want to ping Pat McCarthy and see what he can do for you as he is a renowned big block guy.

Regards,
Glenn