Hasn't every hot rodder built at least one small block Chevy motor? Seems that way to me and to tell the truth, there really isn't anything special about this one. But it will be getting somewhere in the range of 20 miles to the gallon. Paying attention to the parts selection during the buildup and putting it all together correctly will assure a good running engine capable of that mileage and performing well to boot!

The Basics

If this is the first engine you have attempted to rebuild, then I would suggest spending a 20 dollar bill on any of the available "performance books" that take you step by step through the process. All of these books are pretty much the same and contain valuable information such as torque specs., camshaft phasing, and parts selection. As to prices, you will probably be better off buying the bulk of it mail order. In fact, once you have determined bore, crank specs., and the camshaft requirements of your engine, one of the mail order houses can supply you with a full engine kit. The one that I deal with and have had excellent service from is Northern Auto Parts. They use quality engine parts in their kits and I have used their kits to rebuild a variety of different engines for myself and customers. The costs of rebuilding a small block can vary greatly, certainly depending on the condition of the target subject. A normal rebuild which would include machine work for the block and heads, all new wearable parts and gaskets will set you back about $1500. But remember, this will end up being a brand new engine from the heads to the oil pan, so the price is pretty reasonable, and you don't have to spend that sum all at once. You can get the heads done, then the block and then buy the kit. Just don't short change yourself and not do the entire engine with new parts. It will be false economy and you will kick yourself later for having done so. A friend of mine once asked why his "new" motor was already using oil at the 40+ thousand mark and after a few questions, I determined that the previous rebuild had included only a hone of the cylinder walls, using the old pistons and new rings. Sorry, but unless the engine you are dealing with is really low mileage, boring the cylinders and using new oversized pistons is the only way to go.

Measure and Clean

After getting all of your new parts and machined pieces together, it's time to take some measurements. You want to make sure that your machinist did what you told him/her to do. (BTW, that's the last time you will see me being politically correct. I do realize the fact that women are capable of many different jobs. This message brought to you by your federal government) If you lack the required instruments and cannot borrow them, buy Plastigauge to measure at least the bearing clearances. A set of feeler gauges is pretty cheap and should be in your toolbox anyway. Use the feeler gauges to determine crankshaft end play and piston wall clearances. Your next step is too make sure everything is clean. This is messy business here. You are going to get soaking wet cleaning the block, but it has to be done. Before you start, have a spray can of WD-40 or similar product, a bottle of transmission fluid, cheap paper towels, and a large trash bag ready. Once you are pleased with your cleaning efforts, remove as much water as possible using a compressor if you have it, the wife's vacuum cleaner with the hose reversed or the leaf blower. Anything that moves air in a large volume will work. Spray all of the machined surfaces with the WD-40. Two times. Next, apply liberal amounts of transmission fluid to the cylinder walls and using clean, cheap paper towels, continue to wipe the cylinder walls until the paper towels come out clean. Use the large trash bag to cover your work. If you are working without the aid of an engine stand, you will have already provided some sort of clean area to work on I hope. A piece of plywood, masonite or doubled up cardboard will work.

Tips

I am not going to go step by step in the rebuild of the engine. That's where the 20 dollar bill spent will pay off a lot better than the book I would have to write here on the subject. Rather, I want to try and just list some tips for you to remember while you are going through the engine rebuilding process.

• Have a supply of engine oil, white grease, black and blue silicone sealant, and water sealant on hand.
• Make sure that the new oil pickup is secure in the new oil pump. Usually this is not a problem.
• Turn the crankshaft a revolution after every piston/rod assembly is installed. If you feel anything funny, STOP! Check for a reason why before proceeding.
• Work on the engine when you have plenty of time. Do not rush the process, you may forget something very important.
• Use white grease to pack the oil pump, grease the push rod for the fuel pump, and lube the distributor gear on the camshaft.
• Blue silicone is used for any water connections, such as the water pump to block.
• Black silicone is used for any areas involving oil. Pan gaskets, valve cover gaskets and some areas of the intake gaskets.
• The water sealant is used on any bolts that enter a water jacket area. The lower head bolts on each side of a small block Chevy enter the water passages.
• If you order a kit, pay the little bit extra to get Felpro sealing gaskets or a similar product. This saves having to re-torque the head and the special intake gaskets seal much better than the standard ones.
• If you don't plan on building a number of engines, borrow or rent the tools you need.
• Be careful. Machine surface edges can be very sharp, almost like a razor blade.
• Clean everything! Even if it looks clean out of the box. Wash bearings and rings in a bowl filled with rubbing alcohol and lay them out on clean paper towels to dry.
• If you happen to foul up a bearing or ring, don't try to use it. Throw it out. Individual parts can be bought at any auto parts dealer as a replacement.
• Make up your own engine building lube using a 50/50 mixture of 20w50 Racing Oil and STP. Put it in a plastic squeeze bottle, (you know, the shampoo or mustard bottles you always save) and place a liberal amount on engine bearing surfaces.
• An oil can or another plastic bottle works well for applying engine oil to the rings and piston before insertion in the block.
• Without fail, install the camshaft and lifters using a special moly lubricate. This is usually supplied with new camshafts, but it is so important that if you have to buy it, you must do so.
• Once you have your engine built, wipe down the outside with mineral spirits and give it a good coat of paint. Color choice is optional. A lot of hot rodders like to color-match or contrast to the color of their vehicle. My personal favorite has always been a dark gray. Engine problems (water and oil leaks) later on show up well on this color.
• If I can answer any questions for you, Write me at Bfunixbs@aol.com

Combination

I mentioned that I expect my small block to get about 20 miles to the gallon. Given the going rate of fuel today, I think a 20 MPG number is just about the minimum that a hot rodder can live with. The combination of parts used and how they are assembled is the real key to obtaining this goal. Along with good building techniques, I spend a fair amount of time going over each and every part in the engine. On the bottom end of the engine, I use a race piece called an oil scraper. What this does is to remove the excess engine oil that clings to the rotating crankshaft mass and thereby reduce the energy required to turn the engine over. Nothing huge in power gains, but all of the little things add up. I also use a windage tray to keep the oil pan oil from being drawn up and onto the crankshaft as it rotates. Piston tops are polished to remove any sharp edges that could pre-ignite the fuel mixture. The skirts are also checked for roughness and polished up if needed. This will reduce drag on the cylinder walls. My preference for piston rings is a .005 oversize ring so that I can set the the ring gaps myself. This helps the compression numbers. The heads are cleaned up with a grinder to clean up any rough areas in the ports and chambers. If I really feel good, I'll match the intake to the head ports. Manifold of choice lately has been the Edelbrock Performer. I like Holley carbs, they are easy to work on and making adjustments to them is a no brainer. A 600 cfm vacuum secondary will be on this engine. If you are working with a fuel injected engine, you are way ahead of the game. One of these days, I am going to add fuel injection to my ride. Distributor is a late model HEI unit, using an Accel ignition module. Wires are spiral core units picked up at a local parts store. Spark plug is the correct heat range NGK unit. Sorry, but Splitfires have proven in dyno tests and drag tests that I have personally seen to not live up to their advertised claims. A K&N filter unit bought many years ago will be pressed into service again. Camshaft selection is a critical piece that must be matched up with the vehicle's use, weight, final drive ratio and required performance. For my selection, I went with a cam that had about 270 degrees advertised duration with intake and exhaust lift in the .450 area. This is a hydraulic cam, so constant checking of valve clearance is not required. This cam should provide good pulling power from the 2000 rpm range to about 5500. Be honest with yourself when choosing a cam. Are you really going to need one that will pull all of the way to 7500 rpm? I really doubt it, it might be fun every once in awhile to go through the gears, but on a day to day basis, you just don't need it. A convertor with a stall speed of about 2500 looks good at the moment. This engine just doesn't sound exotic does it? But it's the attention to the details that will make the difference. There is also a pretty good amount of work being done that unless you pay a high performance engine shop or do it yourself, you're not going to get.

Copyright © 1996 TKT Enterprises
P.O. Box 101, Montpelier, Va. 23192

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