B18C2 Crossover question

[I heart the SSS]

Hei guise

Before we get started, the car is

- 94 B18C2 motor (vti-r DC2)
- serviced last week with HAMP filter, 5-40 semi syn oil, new plugs, engine flush also carried out.
- New VTEC solenoid gasket
- solenoid itself taken apart and cleaned properly.
- Before a VTEC test is carried out, the car is warmed up for around 20 minutes.

Now, my question is.

Does the second butterfly (6,000 RPM) and the VTEC crossover (4,800 RPM) work together?

I cannot hear my VTEC engaging at around 4,800 RPM, BUT i can hear something occuring at 6,000.

I presume what occurs at 6,000 is the secondary butterfly opening.

I just want to know if they work together, because if they do, my 6,000 RPM secondary buttery is working THUS my VTEC crossover will be to.

I don't think they work together, though.

any thoughts?

[ninzee]

yea this happens to my eg b16a too i hear a slight cross over at 5200 and then again at 5800 but i got it checked out and its normal so im assuming yours would be too but yea

[imratedpg]

im guessing ur exhaust is stock change it ova and u will hear it

[GSi_PSi]

actually it depends if your exhaust is too loud you wont hear vtec havign a stock exhaust with intake you will hear it scream. Vtec really opens up when you have a airfilter or even better a shortram/cold air intake.

My experience with B18C2 , at 4,500 you will hear the change but at 5,500 you will actually feel the revs going quicker toward redline

[I heart the SSS]

That's my point exactly GSI PSI

Everyone apparently hears the crossover at 4,500, where i don't hear shit until 6,000 (butterflys)

I've been told you're supposed to hear a audiable note at 4,500 aswell as 6,000.

BTW the car is stock, just has the airbox lid removed.

[CRXer]

B18C2 stock vtec is 4400rpm,almost unnoticeable x-over on stock motor,testament to honda engineering:thumbsup:

IAB is at 5750rpm,more noticable noise change

[CRXer]

also 4400rpm vtec is at high load/WOT
vtec will x-over at anything up to 5500rpm or thereabouts with lighter engine loads.

[imratedpg]

well in my case when i bought my dc2 stock with just a sri i cudnt really hear the cross ova at 4500 till i changed my exhaust ova

[TheSaint]

having an intake makes it alot easier to hear it all ... get a desent CAI like a Fujita or Injen =D

also it takes time ... the more u drive the car ... the more u will hear the differences ... it took a while before i could identify the lower RPM change but after a few months it was easy to pick

once i installed a Fujita CAI (stock exhaust was fine) it screamed its head off =D

if you REALLY MUST change the exhaust go for a Mugen catback =)

[g_kn]

remember the B18C2 crossover sound note isnt really noticeable compared to the others b series vtec motors,from memory i think its got to do a bit with the design of the b18c2 intake manifold ? .. correct me if im wrong someone

- try putting a stock mufler & SRI ..it should slighlty give you that distinct crossover noise that your after.

[GSi_PSi]

^ i used to think you were rightt... butt after driving my cousins vtir, hearing crxeR's they do have a very noticable vtec cross over....

[dougie_504]

actually it depends if your exhaust is too loud you wont hear vtec havign a stock exhaust with intake you will hear it scream. Vtec really opens up when you have a airfilter or even better a shortram/cold air intake.

My experience with B18C2 , at 4,500 you will hear the change but at 5,500 you will actually feel the revs going quicker toward redline


Yeah man you're dead right.


My EH VTi just has the D16Y1 with a SRI but when you hit the crossover the change in tone stands out like a white elephant - it deepens, quickens and smooths out.

As for my EF8 you can also really hear and feel it coz it's got a CAI but with a 2" 5Zigen exhaust setup it's a little harder to hear than in the EH.

[immigymp]

not sure on this but is but do the vtec's cams switch simultaneouslty?

[vinnY]

^yes on b series
the thing with b18c2's is that they have dual butterflies so it sounds like there's two crossovers

afaik a mates dc2 just changes tone at 4400 then gets louder after 6000
i personally wouldn't worry about it, it's just sound

[fabian0]

Hei guise

Before we get started, the car is

- 94 B18C2 motor (vti-r DC2)
- serviced last week with HAMP filter, 5-40 semi syn oil, new plugs, engine flush also carried out.
- New VTEC solenoid gasket
- solenoid itself taken apart and cleaned properly.
- Before a VTEC test is carried out, the car is warmed up for around 20 minutes.

Now, my question is.

Does the second butterfly (6,000 RPM) and the VTEC crossover (4,800 RPM) work together?

I cannot hear my VTEC engaging at around 4,800 RPM, BUT i can hear something occuring at 6,000.

I presume what occurs at 6,000 is the secondary butterfly opening.

I just want to know if they work together, because if they do, my 6,000 RPM secondary buttery is working THUS my VTEC crossover will be to.

I don't think they work together, though.

any thoughts?

you got it the other way round buddy.

Secondary butterfly in the IM opens at around 5000rpm and VTEC kicks in at 6000rpm.
That is if your car is stock and has not been tuned. For example, my dc2 has been tuned with VAFC2, and my VTEC kicks in at 5000rpm, right after secondary butterfly opens.

In a nutshell, if you hear a louder sound @ 6000rpm, your vtec is probably working just fine. ;)

[SHOGUNOVDDRK]

Turn your bloody Air conditioning off!!!!

[POPSIKAL]

I hear mine change at 4500rpm then can feel it really pulling at 6000rpm, also is louder after 6000rpm

[CRXer]

B18C2 vtec is 4400rpm at WOT....... full stop end of story.

[OMG.JAI xD]

you got it the other way round buddy.

Secondary butterfly in the IM opens at around 5000rpm and VTEC kicks in at 6000rpm.
That is if your car is stock and has not been tuned. For example, my dc2 has been tuned with VAFC2, and my VTEC kicks in at 5000rpm, right after secondary butterfly opens.

In a nutshell, if you hear a louder sound @ 6000rpm, your vtec is probably working just fine. ;)


Lol.
Vtec engages at 4,500 rpm (or somewhere near there. 4400 4450, what ever, it differs by oil pressure. Changing oil viscosity change move it up and down a few rpms).
Secondary intake butterflies open at 6000rpm.
Vtec does not engage at 6000rpm. And you still will hear the note crossover with or without vtec working (if you only have an intake) But it will be sluggish.

Trust me. Having a dc2 with a straight pipe you can DEFINATELY tell the exhaust crossover note, and its at the 4500rpm mark. And exhaust crossover note cannot be heard with secondary intake butterflies. That only effects intake.


With stock air filter, and just the cover taken off it. You gotta have bats ears to hear the crossover at 4500rpm.
The revs are too low for any real notable change in sound. Even with cai or sri.


At the end of the day. Vtec at 4500RPM (differs by a few rpms with oil pressure, temp, viscosity, and all that mumbo jumbo)
Secondary butterflies are opened at 6000rpm.

[An41]

Lol.
Vtec engages at 4,500 rpm (or somewhere near there. 4400 4450, what ever, it differs by oil pressure. Changing oil viscosity change move it up and down a few rpms).
Secondary intake butterflies open at 6000rpm.
Vtec does not engage at 6000rpm. And you still will hear the note crossover with or without vtec working (if you only have an intake) But it will be sluggish.

Trust me. Having a dc2 with a straight pipe you can DEFINATELY tell the exhaust crossover note, and its at the 4500rpm mark. And exhaust crossover note cannot be heard with secondary intake butterflies. That only effects intake.


With stock air filter, and just the cover taken off it. You gotta have bats ears to hear the crossover at 4500rpm.
The revs are too low for any real notable change in sound. Even with cai or sri.


At the end of the day. Vtec at 4500RPM (differs by a few rpms with oil pressure, temp, viscosity, and all that mumbo jumbo)
Secondary butterflies are opened at 6000rpm.

This is spot on.
My crossover is pretty audible at 4400rpm then I cant really hear a crossover at 6000 probably due to my intake still boxed with ducting into the front guard

[Toilet]

When I took off my axle back to have it polished, I took my car for a drive, and for the first time since owning the car, the crossover at 4400rpm was like BAM!!@$!$!@%@
Before that, couldn't hear anything at 4400rpm.
With a cold air intake I could only hear this kinda crossover effect deepening sound at around 5800rpm. Sure found that pretty awesome...
Sorry, what's this discussion about? I lost track within the vtec talk