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Coast High Performance's 347ci Short-Block Is 50-State EPA Legal
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As racers and performance enthusiasts, we like power--lots of it. The problem is that we can't get our power fix and stay smog legal in the Big Brother '90s. Nobody likes to roar down the street with a blatantly-illegal car, opening themselves up to the ticket-wielding Johnny Law. But we do it anyway, all in the name of speed.
Coast High Performance is changing this scofflaw behavior by introducing a new 50-state-smog-legal 347 Street Fighter short-block. Nowadays, getting anything approved as smog legal by the CARB and EPA is a chore, which proves the quality and attention to detail that CHP engineered into the 347 "E" stroker kit.
George Klass of CHP explained to us their year-long effort to get the 347 "E" Street Fighter short-block legalized. Beyond applying with the difficult and necessary paperwork, getting assigned a CARB approval station, and getting the car tested (before and after), there was the actual process of reconfiguring the 347 Street Fighter for it's new "Emissions-Legal" status.
Remember, CHP already has an excellent 347 Street Fighter short-block (also available in kit form) so they didn't have to start with a fresh sheet of paper. Klass explained that one of the best advantages CHP had with the 347 in the smog fight was the Blue Thunder 5.315-inch rod, versus the 5.400-inch rod normally sold in 347ci stroker kits. With the shorter rod, Coast was able to place the wristpin underneath the oil-ring land, allowing better oil control--an important factor when you have a sniffer checking for burnt hydrocarbons. Klass explained that Coast still sells the 5.400-inch rod for non-emission-conscious applications, and that it's a good, strong, viable combination. However, the shorter rod will provide better oil control, thus increasing engine longevity and ring seal. Another less visible advantage of the shorter rod is that a longer, fuller piston skirt design was possible. The 347 "E" short-block is only available with 9.5:1 compression, giving the piston a slight dish.
Of course, the really interesting thing about EPA and CARB legality is that a person can't see past cast-iron--meaning, how could anyone possibly know what kind of stroker or stroker short-block you really have under your hood? Well, a police officer, or visible inspection won't reveal the truth--but a smog test after 10,000 miles certainly can. The CHP 347 "E" has been tested and approved by CARB to be a smog-legal replacement for '88-to-'95 5.0-equipped vehicles.
When you buy a 347 "E" short-block, you also get an exemption sticker/certificate that you can present to anyone doing smog testing. As explained by Klass, there are some interesting aspects to the 50-state smog testing. Even if you purchase Coast's 347 "E" short-block, and bolt-on a set of 50-state legal TFS Twisted Wedge heads, GT-40 intake manifold, and smog-legal headers---the combination may not pass a smog test, although it's very likely that it will. The reason for this is because when CARB tests a part for smog legality (such as an intake manifold), it leaves the rest of the engine stock. So, by adding together combinations of emissions-legal parts, you are legal by the letter of the law, but it is no guarantee of actually passing a sniffer test.
Coast's 347 "E" provides plenty of twist for the masses without concern for the long arm of the law. And it's also very durable, constructed of top-quality components that can handle quite a dose of horsepower. The crankshaft is a cast-steel 3.400-stroke unit, and it is safe for 500 to 600 hp. Blue Thunder makes the 5.315-inch forged I-beam rods, and the Probe Industries pistons are 9.5:1 compression ratio and come with valve reliefs for both Twisted Wedge and Standard-valve-location cylinder heads. All of this is stuffed in a well-machined .030-over 5.0 block.
Klass told 5.0 Mustang & Super Fords magazine that a custom hydraulic roller camshaft is included in the 347 "E" package, and that it was specially designed and configured for use in an emissions-legal short-block. It is not an E-303 camshaft. If you want to retain the smog-legality, you must keep the CHP emissions-legal grind in the car, although Klass said that it is a pretty healthy stick and not as much of a crutch as you would think. Swapping in a Motorsports E-303 camshaft is a big legality question. The only way to know if it'll pass is to sniff it.
All in all, it's hard to believe you can order such a well-made package through the mail. Coast High Performance sells the 347 Street Fighter "E" in short-block form only (with a camshaft), in emissions-legal trim, for $3,095.99. If you aren't concerned with the smog aspect, CHP can still set you up with one of their non-smog 347 Street Fighter short-blocks, long-blocks, reciprocating assemblies, or complete Street Fighter engines. In today's world, all it takes is a phone call.