If vtec wasn't engaging, would a CEL light come on?

Reason im asking is cuz i got a stock gsr with a comptech icebox (which is pretty quiet) and a RSR exmag( which is also quiet).

I def. hear the butterflys kicking in ~5600, but im really not sure if im hitting vtec ~4400.

Should there be a noticable sound change w/ these quiet bolt ons?

(I've searched n checked all teh basics... oil level... cleaned solonoid filter.. fully warmed up, solonode working... switch working...etc)

Anyone else with a similiar GSR have trouble hearing vtec? Not sure if i really "feel it".... but i use stock cams...

do b18c1's have not as loud of a changover?

 

If the car can redline while accelerating, the VTEC is working. Stock GSRs have very quiet VTEC.

 

Even with an aftermarket exhaust and intake (especially an intake as quiet as the Icebox), it's still gonna be hard to hear VTEC activate. When I only had an AEM CAI and an Apexi WS on my GSR, you had to really listen close to hear anything at all during VTEC activation.
When you get an aftermarket header, that when you'll really hear that sucker pop open. That's what happened to me when I added a JDM ITR header and a Carsound cat to my I/E. Such a great sound, get yourseld a header and you'll be very happy with the HP gains <U>and</U> that crack-a-lackin' VTEC activation.

http://www.clubintegra.com

 

So if vtec wasnt working I wouldn't be able to redline the car? the ecu would stop it?

 

GSR's have probably the quietest changeover IMO. My car had very similar mods and yes it's very quiet.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tonyl507 &raquo;</TD></TR><TR><TD CLASS="quote">So if vtec wasnt working I wouldn't be able to redline the car? the ecu would stop it?</TD></TR></TABLE>

No, the car wouldn't produce much power at all in the high RPM range. The car would basically stop accelerating near about 6000 RPM on the non-VTEC cam lobes.

 

Cool, thanks for the info. I took the intake arm off today and drove around a little to see if it would make a sound... It made a little sound differance, but Its definitly working.

Got a chance to get on the highawy with it and you can definitly tell a differance in speed ~4500.

I was just worried cuz my friend got a b16 in a crx and that things like "vrooooooooommmmmmmmmBBBAAAAAAAAAAA"

Glad to see mines workin

 

the reason vtec in a gsr is so quiet is because it is matched very properly from the factory, if you were to dyno a gsr and a type r you would notice the changeover alot more on the graph with a type r then you would on a gsr because the gsr's tq power curves are alot smoother from the factory

any properly tuned vtec car should not have that noticable vtec crossover unless its not tuned right or the vtec lobes are much larger then the primary lobes

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by coptzer &raquo;</TD></TR><TR><TD CLASS="quote">the reason vtec in a gsr is so quiet is because it is matched very properly from the factory, if you were to dyno a gsr and a type r you would notice the changeover alot more on the graph with a type r then you would on a gsr because the gsr's tq power curves are alot smoother from the factory

any properly tuned vtec car should not have that noticable vtec crossover unless its not tuned right or the vtec lobes are much larger then the primary lobes</TD></TR></TABLE>

I agree with the torque matching at the VTEC transition, however, it is quiet due to the intake manifold. You can barely here my ITR cams switch at 4800 RPM with the stock IM.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tonyl507 &raquo;</TD></TR><TR><TD CLASS="quote">If vtec wasn't engaging, would a CEL light come on?

Reason im asking is cuz i got a stock gsr with a comptech icebox (which is pretty quiet) and a RSR exmag( which is also quiet).

I def. hear the butterflys kicking in ~5600, but im really not sure if im hitting vtec ~4400.

Should there be a noticable sound change w/ these quiet bolt ons?

(I've searched n checked all teh basics... oil level... cleaned solonoid filter.. fully warmed up, solonode working... switch working...etc)

Anyone else with a similiar GSR have trouble hearing vtec? Not sure if i really "feel it".... but i use stock cams...

do b18c1's have not as loud of a changover?</TD></TR></TABLE>


If vtec wasnt engaging, i suggest checking all the sensors, oil pressure, oil level, vtec selnoid, that would be associated with vtec not engaging. With my gsr and bolt ons, i/h/e and chipped p28, you can definitely hear the vtec crossover

 

i thought the same when my gsr was stock.

 

I've had 3 '95 GS-R's and I can tell you it is very difficult to hear or feel the VTEC engagement point. It is very easy to hear the secondary butterfly's open at around 5600rpm when you have an intake installed. Especially a short ram.

One interesting thing though...in all of my GS-R's I've had one sort of exhaust leak or another. When I've got an exhaust leak, it's very, very easy to hear and feel the VTEC engagement point. Although I loose a lot of power as well.

Anybody know why?

Another question, since the power increase seems to be much more noticeable when the butterfly's open than when the VTEC engages, is there anyway to lower the engagement point of the secondary butterfly's?