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The SS 496 Project Page 2

Getting started: Basic components, machine work and pre-assembly

SS496 Bare Block

Here is the foundation for the 496 build-up: A rather un-exciting 454 2-bolt main block liberated from the remains of a rotting 1970's chevy truck.

Why not a 4-bolt block? Because at the power level this engine will make, 4 bolt mains are simply not needed.

boring the block

After the normal trip through the hot tank, the block was pressure checked, then sent to the boring bar where the cylinders were taken out to 4.305". The last .005" gets saved for the hone, which was done with torque plates.

Once the block had been bored and honed, it was square-decked to spec to leave the pistons -.005" in the hole. Tech tip: If your machine shop uses a boring bar that registers off the deck surface, make sure they deck the block BEFORE boring it to keep the bores parallel with the crank centerline. This boring bar registers off the mains, so all is good.

Hone Time

Since this is a street engine which will utilize a conventional moly ring set, a 280 grit hone with a plateau finish was specified. Were this a race engine using race rings, a different wall finish would have been used depending on the type of rings used.

Some people believe in building street engines with race finishes and race clearances. I'm not one of them.

Why not?

While there is some power to be had with finer cylinder wall finishes and lightweight ring packages, this power comes at the expense of longevity. That's fine if you plan on freshening the engine on a regular basis for the track, but it's not the way to go for a street-bound engine.

Building a street engine with race cylinder wall finishes and race clearances will free up some power right off the bat, but it also sacrifices a great deal of longevity for the engine. Have you ever noticed how most "race" engines are frequently being torn down to be freshened up? That's because they're normally built with looser clearances and lighter tension rings to reduce friction, which frees up power. However, these parts still wear in just like their street-bound bretheren, and after a (relatively) short time the clearances become too loose and power begins to fall off. Definitely not what you want to deal with on a street engine.

I build street engines with street ring packages, street finishes and slightly tighter clearances. This does sacrifice some power initially, but once the engine has been broken in and the clearances fall into place, the engine runs just as good as it would have were it built with the looser clearances initially, but will have a much longer lifespan between rebuilds.

Dirty Bore Holes

Plenty of grit and other little nasties get left embedded in the cylinder walls after honing. If this trash isn't removed, the engine will destroy even the best set of rings in very short order. After several thorough scrub sessions with hot soapy water and a variety of scrub brushes, the bores were ready to be cleaned. ATF (automatic transmission fluid) does a superb job of lifting the offending materials from the cylinder walls.

The process itself is simple, if not somewhat tedious; pour some ATF on a paper towel and scrub the bores like there's no tomorrow. Lather, rinse, repeat as necessary until the paper towels emerge sans honing poo. Tech tip: wear heavy rubber gloves for this step...that is, unless you like cutting your hands and fingers to ribbons on all the sharp edges.

Lots of Grit

Lots'a nasties right there. Just think of what all that grit and grime would do to your nice shiny new pistons and rings.

It took about a half-dozen scrubbings per bore before the paper towels came out clean. Patience definitely is a virtue at this point of the job.

Cleaned Bores

That's more like it!

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