I'm not sure how much to trust SCC's numbers or analysis, I haven't been getting it long enough. But they say, at low RPMs one intake valve follows the primary lobe, and the other follows a secondary smaller lobe, and the i-VTEC in the K20A3 activates at 2300 where only the intake valves change to the high cam profile. The exhaust valves never change over, thus the reason for the whimpy performance, lack of 8000+ RPM redline and no scream. Basically, the 11:1 compression and the 2.0L Displacement account for the 33 HP over the EX. Essentially, they have the same VTEC system as we do, just with an extra camshaft that has fixed timing. It's no faster than the EX (they clocked a 1/4 in 16.2/85.1).
Does anyone know if this is true?
Meanwhile the K20A2 has all the goodies.
I get that mag too, actually just read the article about the homebuilt CTR, I believe they mentioned that the day they did the tests it was hot out, like REALLY hot out. So those numbers listed are a tad lower than they should be.
i thought that the b series engines w/ DOHC VTEC only acuated one cam as well, the exhaust cam......the first "VTEC" noise that you hear is not the intake camshaft changing, but instead the secondary intake manifold opening or changing.....then when the car goes nuts in the higher rpms ( i think around 6k rpm) that is in fact vtec engaging and switching the exhaust camshaft lobes over....
Ok the K20A3 doesnt have all the goodies the K20A2 does. I wondering about the K20A2 type s and K20A2 type r. I heard the only difference is the exhaust and something with the ecu? So what is the difference?
Quote
[hr]Originally posted by: NeoMagus
There is no K20A2 Type R. It is K20A. Higher compression, higher redline, more aggressive camshafts, factory port and polish to say the least.[hr]
The new K20A engine in the Type R is NOT ported and polished. Honda used a method on the engine heads that resulted in further porting and polishing the engine wasn't necessary.
As per HT:
The differences between the Type R and the American Type-S are subtle, but noteworthy. The engine is designated as a "K20A," but there's no numerical distinction. In Japan, the engine is rated at 220 hp and 152 lb-ft of torque. This difference is achieved through a few tricks, however, these engines do not undergo the meticulous hand porting of the B18C5. Instead, the differences are due to better breathing, compression and computer tuning.
The head on the Type R is cast using a special process with finer grains of sand. The result is smoother intake and exhaust ports, sufficiently smooth that they don't require additional hand porting. The exhaust system is quite different though. In the U.S., the exhaust is immediately collected through a short header into the catalytic converter. Basically, the converter itself is the downpipe for the exhaust system. The Japanese Type R, however, uses a much freer flowing system that is essentially a classic "tri-Y" header. The catalyst is much further down the exhaust stream, allowing for the freer flowing system. These changes certainly account for a good chunk of the Type R's increased power.
Another important factor is the increased compression ratio. The American Type-S has a good 11.0:1 ratio, but the Type R uses different pistons with a chromoly skirt. The compression rate is even higher, at 11.5:1. It also means that the Type R really wants to drink high-octane Japanese gasoline. 100-octane gas is sold at the pump in Japan, cushioning the system against detonation much better than the 91-octane swill we have in California.
It's pretty simple. The new Si is damn heavy. If it was under 2400lbs like all of the older hatchbacks, they'd have a winner. But they're going the way VW went. Look at the old late 80s early 90s GTis and then compare them to new ones. They've gained almost 1000lbs! Pity honda is going that way, but i guess that's what happens when a car is designed in europe.
Quote
[hr]Originally posted by: Neonmike
It's pretty simple. The new Si is damn heavy. If it was under 2400lbs like all of the older hatchbacks, they'd have a winner. But they're going the way VW went. Look at the old late 80s early 90s GTis and then compare them to new ones. They've gained almost 1000lbs! Pity honda is going that way, but i guess that's what happens when a car is designed in europe.[hr]
I think most recent cars are natually heavier than their previous generations. Car makers sacrificing performance for the convenience of luxory or in other words that sense of "refinement." Because of the new Si, the new 200HP Civic Type R might make you wonder about it's performance. I don't have any #s but I do have my friend who's overseas with the experience. He told me the new Civic Type R is not as good as the previous 160HP one and though Type Rs are lighter, the CTR from what it seems doesn't seem light enough. The engine is the same as the Type S as we all know but the previous CTR hatch actually felt like more on terms with being a performance car and ends up being the preferable one of the two CTRs.
On top of that the exhaust note sounds shaweeeeeeeet.
