Thread: so, how balanced are SR20's?

Put simply, you're wrong and have no clue what you're talking about.

x2 i dont think that nissan sacraficed ANY smoothness for torque, and the reason hondas dont have torque is their lack of displacement.

i dont think either sacraficed anythng they have ,mearly different design concepts and designs btween the 2 mfgs

Wow, I may be making educated deductions, but I don't have the kind of lack of respect for others that you demonstrate.

I don't think that kind of aggressiveness was even close to appropriate.

If you talk to people like to their face, I feel sorry for you.

Seriously guys take it easy. The SR20 is a thrashy little motor and it has everything to do with the powerband and the architecture of the build.
Uninitiated People think I am breaking my car when I get on it and that's every set-up.

Product Planning 101 is all about prioritizing specific design goals.

As far as I'm concerned, forums are a place for information. I take it upon myself sometimes to point out miss-information, as it is like a plague forums have to deal with. There's a reason many, many people in the automotive community know little to no correct information about how engines work and you're part of the reason why. I can't actually delete your comment (sadly) so I chose to negate your comment with something hopefully others will take seriously. If I offended you with my comment, imagine a couple of smiley faces sprinkled here and there, coupled with a few "lol"s and you should be all set.

How long have you been here? One year at the most? Puleaze sprinkle me with your wisdom.

I have driven SR20 cars since the first in 91. What were you, 8 years old? Probably telling people they don't know squat about see-saws.

And since when is a computer programmer an automotive engineer? Maybe you should actually graduate before you regulate "miss-information" [sic].

What a pompous jackass. LOL

Quality of thread just took a dump, keep the argument to PM's guys don't ruin a perfectly good conversation with private matters.


Dudeman

About 6 months.


Name me one member who's been here longer than 6 months.


You sated two things in your comment that I disagreed with. Firstly, you said Nissan gave up engine smoothness for torque. Conversely you said Honda gave up torque for engine smoothness.

The two are not unrelated, but what you need to understand is why an engine is smooth, or revs smoothly. You also need to understand what makes one engine have more torque than another. Once you understand these two things you'll realize why what you said is incorrect.

Engines run smoothly when bearing tolerances are tight and rotational mass is balanced. There are many ways to balance rotational mass.

You can match weights/lengths of pistons and rods (Honda spends more time/effort/money doing this than Nissan).
You can employ balance shafts that dampen primary resonant vibrations in the engine (Neither Honda nor Nissan employs these in the engines we've been talking about).
You can employ harmonic balancers that dampen secondary resonant vibrations in the engine (Both Honda and Nissan employ these in the engines we've been talking about).

So far Honda has one up on Nissan in this department, and in my opinion makes all the difference between the motors we've been talking about.

As for torque, this has very little to do with vibrations. That being said, a smoother engine (Honda) will tend to make power earlier in the rev range, and thus generate more torque (all other things being equal). Simply put, Nissan decided to have a longer stroke than Honda. This longer stroke provides more torque, given the same engine displacement. You might think that having a longer stroke would lead to a rougher running engine, but that assumption is not true. It is all in the balancing.


Wow, you actually got that right. I'm surprised.


If one student explained how they worked incorrectly to another student, I probably would have butt in, yes.


When they hold both titles.


Graduate what? By your calculations I'm well out of college.




If there's anything else about engine torque or smoothness you'd like me to explain, I'm in a much better mood than I was when I wrote my previous post so I'd be glad to teach you.

I'm done except to clarify....

1. "Here" as in the SR20 forum world. Big picture.

2. In the Product Planner world you have objectives. Some may get more priority than others. "Sacrificed" may have been a misleading term. Semantics.

3. College. By calculations, it would be easy to predict you'd be out of college, but I guess life gets in the way sometimes (props to you...Im not being sarcastic).

The end product is not run by engineers. Its run by committee. You can theory-this and theory-that all day. But in the real world you can only second-guess the "why"s unless you are privy to the corporate decisions.

By the way I have owned at least 1 SR20 since they've been out. I have also owned Honda and Subaru 4cylinder cars since then. I was also in Engineering School until I bailed. I'm 35. I was on the SE-R Mailing List since almost the beginning as well as both forums. I have also been included in product planning meetings on a corporate level.

"You have no clue what you're talking about" is a pretty naive and unnecessarily bold thing to say. I understand your principles, but you're young enough to discern between a wiki and a discussion forum.

I won't add anymore to this thread, but I do invite you to create one. I'd love to hear the topic from a purely technical aspect.