A question about the engine...

[NineOne]

Alright, as I understand it the RSX (not the S) and the SiR share the same engine (don't start withthe B1c...god knows what, I'm no good with engine codes), what component gives the RSX the extra 10lb-ft of torque? It's not a big issue, but I am curious, could anyone shed some light on this for me please?

[SiR Medic]

The RSX engine doesn't have a balance shaft, that's one thing.

Also the RSX suffers a slight parasitic loss due to its conventional hydraulic power steering, where the EP doesn't due to the EPS (Electric Power Steering)

I don't know if this would explain everything, but its a start, and an example how the engines are close, but not EXACTLY the same.

[Tekdemon]

Our engine is betterer =P

But only slightly...and most of the differences really aren't in the engine itself except for the throttle body size...and that's not really in it in it.

But yeah anyway, they get more torque because of their dual runner intake setup versus our single runner...this of course means we have more HIGH END POTENTIAL but they have better low end...

That's why the hondata raised revline works better on our engines versus on the RSX(where they didn't raise the rev limit nearly as much).

Anyway, not a big difference either way heh...it'd still be a very close race if you decided to race an RSX.

Lower your EP a LITTLE, put on stickier tires, I/H/E and it'll be over =P

[grooveline]

... the base RSX has more torque than us because it is equippen with a *dual stage* intake manifold. there was a great article is sport compact car a while back about variable and fixed geometry when dealing with intake manifold.

short runners are for torque.

long runners are for higher horspower.

[chunky]

Originally posted by grooveline
... the base RSX has more torque than us because it is equippen with a *dual stage* intake manifold. there was a great article is sport compact car a while back about variable and fixed geometry when dealing with intake manifold.

short runners are for torque.

long runners are for higher horspower.

you got it backwards.

short runners = more high rpm flow.

long runners = higher flow velocities at lower engine speeds, thus more low end torque at the expense of high rpm flow.

[Tekdemon]

Chunky is right =P that's what I was talking about in my post too...the dual runners are thinner than ours and longer...and the 2nd runner opens up at higher RPM to allow higher flow rates...

But we just have the big ass single runner. So at really high RPM we have better flow than their dual thinner runners.

[Burgh]

The torque curve on the base rsx is a thing of beauty. No midrange dropoff like ours has.

[NineOne]

Originally posted by Tekdemon
Anyway, not a big difference either way heh...it'd still be a very close race if you decided to race an RSX.

Lower your EP a LITTLE, put on stickier tires, I/H/E and it'll be over =P

If I get the SiR I plan on racing my friends RSX premium ;)
But since it's the same engine we'll probably get the same mods at the same time :P


So what exactly is it that you're telling me here? The RSX has more low rpm power and the SiR has more high rpm power?
And this is due to the intake manifold...So how is the SiR engine better?

[grooveline]

Originally posted by chunky


you got it backwards.

short runners = more high rpm flow.

long runners = higher flow velocities at lower engine speeds, thus more low end torque at the expense of high rpm flow.

no, you have it backwards. short runners are for torque, and longer runners are for high rpm flow. how can i prove it? install a CAI, and you lose torque down low, but it wails once it you get in the upper RPM range. And and SRI will not give you the torque loss, but it won't provide as much HP as the CAI. I rest my case, otherwise... you can go to Sport Compact Car magazine and look it up and read for yourself. they also include wonderful diagrams.

[Surprise]

You know how all the F1, NASCAR and motorcycles use very long runners;)

http://www.4-linkwizard.com/images/Gif/dynopull2.gif
http://next.web-cars.com/wallpaper_img/ferrari_f1_800.jpg


;)

[Tekdemon]

Originally posted by NineOne


If I get the SiR I plan on racing my friends RSX premium ;)
But since it's the same engine we'll probably get the same mods at the same time :P


So what exactly is it that you're telling me here? The RSX has more low rpm power and the SiR has more high rpm power?
And this is due to the intake manifold...So how is the SiR engine better?
Most basic bolt on mods increase air flow right? Intake, Headers, Exhaust.
Since the larger shorter single runner has HIGHER AIR FLOW, it has LESS TORQUE, because torque comes from backpressure...

Now see, when an RSX with it's dual runners gets the same mods, it's flow is limited by the runners and the fact that there is a smaller throttle body.

Since our engine has the shorter runners...we thus respond to mods better.

=)

[Tekdemon]

Originally posted by grooveline


no, you have it backwards. short runners are for torque, and longer runners are for high rpm flow. how can i prove it? install a CAI, and you lose torque down low, but it wails once it you get in the upper RPM range. And and SRI will not give you the torque loss, but it won't provide as much HP as the CAI. I rest my case, otherwise... you can go to Sport Compact Car magazine and look it up and read for yourself. they also include wonderful diagrams.
This is a bad arguement dude...
*sigh*
Think about it...for one thing your arguement doesn't even work on our cars most of the time because a lot of the SRI's flow better than the CAI's and offer more torque loss and better higher end gain...but let's forget about that for a second.

See the reason SRI's usually offer less torque loss, is the same reason long thin runners offer less torque loss. Air flow is LESS.

A CAI offers MORE air because it has colder air. Thus the flow rate is HIGHER. This is why there is more torque loss->Just like the SHORTER WIDER RUNNERS.

An SRI on the other hand suffers less torque loss on average because it gets warmer air, thus there is less air flow(mass wise) and...thus it is more restrictive on flow, JUST LIKE THE LONGER RUNNERS!

Anyway, the point is, in high end performance, short, wide runners rock the world. If you want torque you should restrict flow. However, when it comes to race cars it's silly to choke the high end...all the race cars have engines going 13000+RPM...and if you think 7000RPM gets choked by long runners, 13000RPM gets slaughtered.