7-X performance modifications

Michael-



Ken's site is a wealth of information for step-down owners. Do your research, do it well, do it often and stay sharp.



I won't go into the details of the 7X here, as you can peruse that on your own. There is conflicting opinions of the modifications concerning 7X's. Not in the sense of what goes into the engine, but as to their roadability, reliability and longevity. There is a tremendous amount of untapped horsepower and or torque in a stock 308, depending on your particular application or "wants".



Keep in mind that a stock 308 is nothing to sneeze about. Put up against any of it's contemporaries in a "stock to stock" application, and, while not the fastest or fleetest on the straightest of roads, the turns and twists and curves will make the brand-X believers of the road truly yield to the step-down. A 7X modified engine can turn those scales in your favor, and a full-blown "modern" application which incorporates modern technology will flat out wipe out any other flathead around. Keep in mind that the beauty of the flathead is in having the flathead itself. Excessive tinkering can turn it into something that it is simply not.



Now, philosophically aside, keep in mind that a 7X'-ed engine, once modified, will always be that and for all practical purposes, is irreversible. Additionally, a full-blown 7X is not really "street-able". Face it, it's a loose engine that was designed to run flat-out. Racers "back in the day" would replace timing chains every 500 miles. If that sounds like fun, more power to you.



A "street-tamed" 7X is a more practical approach to a Hornet engine, which is precisely what I'm preparing to do for the convertible. A milder cam, a roller timing chain which is currently being constructed, a full line bore are some of the elements I'm incorporating along with the normal 7X "requirements". Additionally, the work required to accomplish this is, again, irreversible.



There's certainly nothing wrong with having an engine on the stand, 7X it, add a triple-weber induction system, whatever. Swap it out for the stocker for the weekend, go hit the vintage tracks and have a ball. Come Monday, swap it back out, put the 7X back on the run-in stand and make the modifications you want to get another .3 out of your time, etc. Just something to think about. My point is when you have an original engine in your original Hornet, which you will have, 7Xing your stock 308 will forever "change" the nature of your originality.



One more thing: there's a lot of simple little "tricks" that can be done without doing a full 7X modification. Simply adding headers and removing your stock exhaust manifold will yield an additional 20-30 hp. It's one of the best $$$ to power gain ratios you can get.