So, What is the difference....and do you think HONDA will start to put iVTEC on next Generation S2000?

 

Watch out for dogs...

 

i-VTEC stand for intelligent-VTEC.

this is a quote from Autozine:

Engine

Honda's B18C engine - which powered the previous Type R - was famous for explosive power and revability without sacrificing too much drivability (unlike B16C). However, after more than 10 years of evolution it finally came to an end and is replaced by a new 2.0-litre four, engine code K20C.

K20C is not developed exclusively for Integra Type R. It is a derivative of the mass production K20A which started serving Stream MPV recently. No matter K20A or K20C, they differ from the old B18 by three main improvements: 1) increasing displacement from 1797 to 1998c.c.; 2) using roller rockers to reduce friction at valvetrain; 3) in addition to the existing 2-stage, cam-changing VTEC, they gain a cam-phasing variable valve timing (VTC) mechanism at intake camshaft like many manufacturers do. Honda calls this combination of VTEC and VTC as i-VTEC, where i stands for intelligent (think of iMac or iPaq, or VVT-i ?). See it this way, the conventional VTC varies the intake valve timing continuously and smoothly throughout the whole rev range, so it flattens torque curve, which used to be the biggest weakness of VTEC. The VTEC, on the other hand, switch from "slow-timing, low-lift" cam lobes to "fast-timing, high-lift" cam lobes at around 6,000 rpm, optimizing ultimate power.

This sounds fabulous, but by no means in Type R territory because every Stream and regular Integra has them. What make the Type R producing some 60 more horsepower are: 1) with VTEC at both intake and exhaust camshaft instead of just intake side; 2) 11.5:1 compression ratio instead of 9.8:1; 3) straight and large intake port and manifold (but devoid of two-stage variable manifold as found in the lesser models); 4) two-stage variable back-pressure muffler; 5) lighter weight moving components such as high-strength con-rods, forged crankshaft and lightweight flywheel; 6) piston skirt added with lower friction coating.

As a result, maximum power becomes 220hp (JIS) at 8,000rpm, up from the previous 200hp at the same rev. Although not as astonishing as the 250hp (also JIS) S2000, the i-VTEC engine is cheaper (shares a lot of components with the mass production version) while being more user friendly, in other words, more torquey at low to mid rev. Peak torque is 152 lbft at 7,000 rpm, equaling the S2000 but occurs 500 rpm earlier. Although this cannot match the old Type R's 6,200 rpm, at any time the new engine deliver stronger torque, especially below 3000rpm, and is more linear.

Honda did not say a word about some traditional Type R goodies such as forged connecting rods, forged and polished pistons etc, letting us believing that the new engine is designed for higher production no. and lower cost. This coincide with the fact that the new engine is no more revvy than the old B18C although it has bigger bore and shorter stroke - the new combustion chamber is pure square, with both bore and stroke at 86mm compare with the old engine's 75mm bore and 90mm stroke. In terms of power per litre, the i-VTEC is also no more than the old VTEC.

be careful reading the S2000 part, maybe I-VTEC is not as good as the VTEC S2000 is using.

 

this quote mentioned that I-VTEC is cheaper to made than the F20C VTEC.

 

You have no idea how restrained I was.....

Would you like PB&J with that?

 

You know I looked at the post and thought naw let it go....BUT I just couldn't resist...just TOOO tempting!

 

Just so you knowm the Vtec vs. the Salamnder is a meet forum.. I'll move it to Under the Hood

 

Variable valve lift is accomplished by opening the valves with two different rocker arms and camshaft lobes. In the past, Honda operated VTEC engines with three rocker arms: two to open the two intake valves and a third that could be locked to the other two causing them to follow a different camshaft profile. With the new "two rocker" design, only one valve is opened at lower engine speeds. This causes the intake air fuel mixture to swirl, optimizing combustion at lower engine speeds. At a rpm programmed into the engine computer, oil pressure is used to lock the two rocker arms together. Now both valves open together but followthe higher camshaft profile the second rocker arm follows. Increased performance is one advantage of the i-VTEC system. The torque curve is "flatter" and does not exhibit any dips in torque that previous VTEC engines had without variable camshaft timing. Horsepower output is up, but so is fuel economy. Optimizingcombustion with high swirl induction makes these engines even more efficient. Hope you got all this.

 

all you need to know is the fact that you have the best VTEC engine from Honda that is 4 cyl.
(for Now)

 

you know, i could swear our torque curve on a dyno looks as flat as it gets.