A critical component to any engine is the valvetrain, if you get it wrong, you don't get t
Forgings, provided they're good forgings, are the best, but billets and even some castings can offer acceptable alternatives, depending on the application. When it comes to 180 degree cranks for V-8's, forget it.
Here again, a good forging is best, but almost everybody uses Carrillo or Crower steel rods to get the sizing they want. As for aluminum and titanium rods, forget it until tomorrow. They work, but expert techniques are needed. They're not for the beginner.
Lots of considerations here, but none is more important than reliability. Dome shape, skirt shape, ring placement, compression ratio-you can screw up pretty badly in this area unless you get some good advice.
Tried-and-true combinations are the best bet here. Don't try to run extra-tight end gaps or super-low-tension stuff like the drag racers. Sealing the combustion pressure and keeping oil out of the combustion chamber are the first goals for reliability. Remember, the idea is first to finish, then to finish first.
Same story, go for reliability. You gotta keep from spinning 'em, and you gotta get the clearances right.
More guys mess up here than you'd believe, and it ain't a good place to make mistakes. Here's where a lot of engines go bye-bye in a big hurry. Dry-sump systems are best, but wet-sumps can be made to work too. The only problem with a wet-sump is that it's like having a live rattlesnake in the car with you-the better the car handles, the more likely the snake will strike. The pickup has to be done correctly and you have to keep 10 psi oil pressure for every 1,000 rpm. For example, at 7,000 rpm, you need 70 psi hot oil pressure under racing conditions. And if the oil temp is getting up to 280 degrees or hotter, you're in real serious trouble. Get ready for another snake bite.
All I can say here is, if you're trying to bore, hone, or fit rings without 'em, you're in trouble before you even bolt the engine together. Honing is another controversial subject, but let's just say you can't get a cylinder wall too smooth, provided you don't burnish it.
Float 'em if you legally can, and don't bush stock rods. Just get the pin clearance right and make sure they get oil.
The best parts in the world won't cut it if they aren't put together correctly. Courtesy o
Again, this is no place for a beginner. If you want, buy from an expert and then try to copy the expert; but you're gonna need a flow bench to know where you stand. Who knows, you might find a better way. There's always room for a new expert.
Most everybody agrees that studs are better, but very few really know why. Studs don't pull a head or a main cap down any tighter, so what's the big deal? A lot, once you understand it. And then there's the business of getting the bolt bosses perpendicular to the bolt centerlines. Of course, you've already been doing that, right, and you understand what happens if you don't?
Rocker arm geometry and stability at high speed could be the subject of a complete book. Shaft-mounted versus stud-mounted, materials, ratios, roller tips, oiling and on and on. It's another area where if you get it wrong, you don't get to finish.
One word, reliability, says it all here. At 7,500 rpm, each valve opens and closes more than 60 times a second. In a 3 1/2 hour race, that means each valve and spring has to cycle over three-quarters of a million times, and it has to do it right every single time or else you've got big trouble.
The best parts in the world won't cut it if they aren't put together correctly. Trial fits, prelubing, gasket sealing, torquing; it's all important.