Just wondering what you guys think.

[nastyNater]

whats a short stroke for a 1L 10 cyl? less than 1"?

[Shpyder]

Originally Posted by nastyNater

whats a short stroke for a 1L 10 cyl? less than 1"?

lmao, could be. I think the smallest any team went was around 1L. But I imagine their redline was pretty slick to make up for that.

[nastyNater]

technology is getting insane....they push those cars to the limit for hours under amounts of stress that people like us cant relate too.

[knorwj]

hmm I was under the impression that a car that makes the torque early then maintains it was ideal, not a car that doesn't build it till higher. Thats why our honda engines are so nice because they may not have alot of torque but they maintain the torque curve for a long time allowing us to build Hp off the rpms. If you look at an old 5.0 mustang dyno it will build alot of torque quickly but once it peaks it drops off, however look at a B18c or something, it will build not even half the torque of the mustang but it will peak and then maintain it for a while allowing you to make much more hp off of a smaller displacement engine than normally possible.

[Shpyder]

Originally Posted by knorwj

hmm I was under the impression that a car that makes the torque early then maintains it was ideal, not a car that doesn't build it till higher. Thats why our honda engines are so nice because they may not have alot of torque but they maintain the torque curve for a long time allowing us to build Hp off the rpms.

Here is an excellent link regarding the subject, I'm sure you'll fnid it useful:

http://www.automotiveforums.com/vbul...d.php?t=210613

[knorwj]

Originally Posted by Shpyder

Here is an excellent link regarding the subject, I'm sure you'll fnid it useful:

http://www.automotiveforums.com/vbul...d.php?t=210613

hmmm i think he's a little off on some of his facts. For instance he says that to make more HP you must increase TQ? That is not true at all, you need to increase either TQ or RPM to make more HP. but increasing rpm will only work if the engine maintains its torque.

HP= (TQxrpm)/5252 therefore increasing rpm OR torque will increase HP.
However all i was saying before was that in order to produce more HP the engine has to be able to produce torque at a given rpm, so revving without torque will not get more HP, hence why I said the torque curve must be sustained.


So ideally you want an engine that creates max torque at a very low rpm and then maintains it throughout the rpm range. otherwise the torque will either max out then drop or take forever to make max torque, if either of these happen you will not gain the maximum HP number out of the equation. See a engine that makes max torque low and then maintains it allows the highest possible HP at ANY given rpm rather than just up high.

[Shpyder]

Unless you didnt read the entire thing, his facts are spot on.

What do you mean by the engine "maintaining" its torque? I have yet to see a torque curve that remains at its climax throughout the RPM range. It is a skewed bell curve, and all figures quoted for marketing and other purposes are all peak figures. If you can make an engine with a flat torque that zips skyhigh at 2K RPM and stays there, I'm sure every car maker in the world would want to buy your idea. The first thing to understand is that a torque curve peaks and then drops down. You want to shift where the HP curve (which is tq. per unit time) declines after peak. Its all about that, and gearing.

HP is the only thing that moves. It is torque expressed as a rate. Torque itself does zilch. The second your torque moves something, it overcomes static friction, it becomes horespower.

Revving without torque wont give hp? How do you suggest Hondas stick with muscle cars on the track? Miniscule torque figures coupled by a high redline (hence shift point and hence peak torque) generates enough horsepower to beat those V8 guys, who then give the competition high torque low-rev V8 power. We hear about that every single day on this sub-forum. Hondas sure as sugarsht don't make torque like those muscle cars. So why do they win?

Its ALL about HP. Example.

A 200 torque car reaches peak torque at 18,000 RPM (say one of those F1 cars).

A muscle V8 with 500 ft/lbs reaches peak torque at 6000 RPM. What would trap a higher ET?

The first car. Why? The tq. is pathetic in itself, but it peaks at 18,000 RPM, generating a massive 685 horses. The best with available technology we can do, is to push the peak tq. further out into the RPM range, so we delay shifting. The V8, for all its brawn, reaches its peak very early in comparison, with 571 HP. The first car makes full advantage of 1st gear wheel torque. The other one has lots of tq, but must shift earlier, and wheel torque decreases.


This is a good resource. I spent a lot of time reading and re-reading. Check out these links, both have been written by pros.

http://www.automotiveforums.com/vbul...tions+shifting

http://www.geocities.com/MotorCity/7177/torquehp.html

[nastyNater]

i read that thread and i agree w/ Shyper. The guy that posted it knows exactly what he is talking about. I didnt see anything in the thread that seemed like an opinon or guess...just facts.