Civicloution2001

I've heard a lot of stories, but most of the racers I know aren't all that sure on this subject... Can anyone clear this up, and tell me why people are doggin' the VTEC-I
on the RSX???

sohc_boy

well i know that vtec-e was only in the hx and that was tuned for economy.
vtec-i i think is basically the same as vtec except it adds variable cam timing as well i think thats how it works. vtec works by having an xtra cam lobe with a more aggressive profile and siwtches over to the big lobe at a certain rpm and speed. people usually dog the vtec-e not i at least i haven't heard anyone badmouth the new vtec-i yet.

Civicloution2001

What about the 2001 ex, is that the old VTEC, or the VTEC-E???

sohc_boy

vtec

2.0L EK

It was also in the 92-95 civic VX
-Alex

Blazin Si

*EDIT*

2kTypeRHatch beat me to it.


[Modified by Blazin Si, 7:15 PM 3/20/2002]

E. Honda

Whos knockin I-VTEC? its brilliant! 2001 was a bad year for Honda? WTF!

Spade

2001 HX and EX both have VTEC-E.

VTEC = 3 Cam lobes and 3 rockers. Once VTEC is engaged, the middle rocker locks into the two outer ones so they both follow the larger (middle) lobe on the cam.

VTEC-E = 2 Cam lobes (one larger than the other) and 2 rockers (roller rockers). Once VTEC-E is engaged, the primary rocker is locked to the secondary and both follow the higher cam lobe.

BTW, the HX cam is more aggressive than the EX cam......now whether or not the rockers are the same ratio is yet to be determined.

D16Y5
Intake
Primary......38.4mm
Secondary..32mm
Exhaust.......38.8mm

D16Y8
Intake
Primary.....36.8mm
Mid............38.3mm
Secondary..37mm
Exhaust........38mm

Difference of .1 mm on the intake and a whopping .8 mm on the exhaust!

Follow link to see the whole tread. https://honda-tech.com/zerothread?id=101349

ckkl

Just to add to Anger's post (which was very good), i-VTEC controls variable cam timing on the intake cam ONLY.

For the lower spec i-VTEC engines e.g. K20 found in Integra iS (regular RSX?) the i-VTEC and VTEC are for the intake cam ONLY i.e. exhaust cam uses same profile the entire way.

For performance i-VTEC engines, e.g. RSX-S and DC5 ITR, there is regular-style VTEC on both intake and exhaust side (i.e. 3 lobes per cylinder x 2 for intake and exhaust ugh ugly sentence) however, i-VTEC only changes the cam timing for the intake cam.

I believe this is actuated using a solenoid that engages a helical gear at the end of the intake cam. The helical gear rotates to either advance or retard timing.

I hope I'm right...

Cheers!

Civicloution2001

Ok I wasn't knockin' VTEC-I, but 2001 could have been a better year. 1.7 liters, but no more horsepower??? How about the fact that my car was made for emissions, and not any sort of racing. And if it was please enlighten me, because the SOHC that I have has some of the slowest accleration times that I have ever seen in a car... I have enjoyed toying with it, and I do think that it looks better, but I am still a little dissapointed... with it's speed and emissions BS

Dave421

Uhh, sorry but the 01 & 02 EX are VTEC, NOT vtec-e

Spade

Um, they are VTEC-E!!!!!!!

EG8R

VTEC-i is not the same as i-VTEC....

ckkl

<VTEC-i is not the same as i-VTEC....>

What're you talking about man...

I know about i-VTEC e.g. K20 engine on RSX-S, DC5 and EP3.

What's VTEC-i?

non vtec

the 2001 dx and lx civics do have more horsepower with the displacement gain. the ex does not. previous dx and lx's got 106 hp and 103 lbxft as opposed to 115 and 110

SloEG

I don't know how much R&D honda did on the I-VTEC motors, but my friend blew his RSX-S motor couple months ago.......piston flipped, punched a hole in the oil pan and smacked the tranny. This happened to 6 other people from the same ACURA dealer he bought it from. Another guy dropped in Integra Type-R cams (DC5 of course) in his RSX-S and the cams snapped.