Even more interesting article:

http://chevyhiperformance.com/techar.../148_0401_imp/

 

Another:

http://chevyhiperformance.com/techarticles/0304_zoops/

 

not saying anyone is right or wrong here but I am curious as to why a lot of the exotics tend to go with small stroke large bore configurations.

 

Because they are built to be road racers, not 1/4 mile monsters. They'll do well in the quarter but they are made to be in a certain rpm band, almost always above 3500 rpm so they will make good power coming out of the corners and rev like crazy on the straightaways.

 

They can get more air and fuel into a large bore/short stroke engine than a small bore/long stroke engine because the bigger bore allows for larger and/or more valves.

A big bore engine really sucks.

 

Hey... Screw it!
I'm gonna build one of each, and test each of them out to find out for myself which is best.
And when I'm done, I'll be back and let you know that I should have just gone out and bought an LS1.

One of the guys (that I know of) is building up one of thost short stroke 350s. I'm looking forward to hearing how it does.
We've all heard reports of how strokers do.

 

No question about it. If cost is no object and I could build either a small-bore long-stroke engine or a larger-bore shorter-stroke engine (same displacement), I'd go with the later. However,, a 4.03/3.48/5.7 combination with better heads than a 4.165/3.25/6.0 combination will run circles around it! Same heads, it's going to come down to how well the cam is matched to the entire combination - engine and car. Same car, same cam,, it's going to come down to how well the cam FAVORS one OR the other,, or it can come down to the installed intake centerline. It can even come down to how well you or the other guy can tune an engine. In fact,, I've found the vast majority of people that want to go fast CAN NOT tune / set up a car,, and if YOU fall into that category,,, it's not going to matter which one you build.

Now,,,, if you can tune and REALLY know what you're doing, if you're going as fast as you can with a typical combination (most are not - even the ones that do know what they're doing are usually in a steady state of learning), you're racing competively, you have the money to spend on it, or you are just not going to be able to sleep at night knowing you're not running what you believe is the best possible combination out there,, then that's another story. To me,,, it's all about what makes you happy. What makes me happy is going as fast as I can with the money I have available to spend and that usually doesn't include spending extra money on a bottom end that doesn't increase the displacement.

 

They are built for a completly different purpose. They want to get the most power possible out of the smallest lightest engine possible. They are all about going fast, not getting there fast. As those engines redline at 9000+rpms.

Since hp=tq*rpm, you will always make more hp in the upper rpms, just like the exotics want to. But if the wanted to build a really powerful engine it would be bigger and weigh more defeating their mantra "weight is the worst thing ever."

No we are taking extreme cases it would be very difficult to build a long stroke motor to attain 9000+rpms. The interial forces are just to great for the parts to survive. But this is a very extreme case where most engines would let go. Of course i'm not saying you couldn't do it.

Their other mantra is "hp sells, why build a big powerful engine when a small light engine can have the same peak hp."